diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/events/uprobes.c | 4 | ||||
| -rw-r--r-- | kernel/trace/Makefile | 1 | ||||
| -rw-r--r-- | kernel/trace/ftrace.c | 215 | ||||
| -rw-r--r-- | kernel/trace/trace.c | 57 | ||||
| -rw-r--r-- | kernel/trace/trace.h | 193 | ||||
| -rw-r--r-- | kernel/trace/trace_events.c | 49 | ||||
| -rw-r--r-- | kernel/trace/trace_events_filter.c | 12 | ||||
| -rw-r--r-- | kernel/trace/trace_events_trigger.c | 1437 | ||||
| -rw-r--r-- | kernel/trace/trace_kprobe.c | 838 | ||||
| -rw-r--r-- | kernel/trace/trace_probe.c | 440 | ||||
| -rw-r--r-- | kernel/trace/trace_probe.h | 224 | ||||
| -rw-r--r-- | kernel/trace/trace_stack.c | 2 | ||||
| -rw-r--r-- | kernel/trace/trace_syscalls.c | 14 | ||||
| -rw-r--r-- | kernel/trace/trace_uprobe.c | 487 |
14 files changed, 3065 insertions, 908 deletions
diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c index b886a5e..307d87c 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -1854,6 +1854,10 @@ static void handle_swbp(struct pt_regs *regs) if (unlikely(!test_bit(UPROBE_COPY_INSN, &uprobe->flags))) goto out; + /* Tracing handlers use ->utask to communicate with fetch methods */ + if (!get_utask()) + goto out; + handler_chain(uprobe, regs); if (can_skip_sstep(uprobe, regs)) goto out; diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile index d7e2068..1378e84 100644 --- a/kernel/trace/Makefile +++ b/kernel/trace/Makefile @@ -50,6 +50,7 @@ ifeq ($(CONFIG_PERF_EVENTS),y) obj-$(CONFIG_EVENT_TRACING) += trace_event_perf.o endif obj-$(CONFIG_EVENT_TRACING) += trace_events_filter.o +obj-$(CONFIG_EVENT_TRACING) += trace_events_trigger.o obj-$(CONFIG_KPROBE_EVENT) += trace_kprobe.o obj-$(CONFIG_TRACEPOINTS) += power-traces.o ifeq ($(CONFIG_PM_RUNTIME),y) diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 72a0f81..cd7f76d 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -85,6 +85,8 @@ int function_trace_stop __read_mostly; /* Current function tracing op */ struct ftrace_ops *function_trace_op __read_mostly = &ftrace_list_end; +/* What to set function_trace_op to */ +static struct ftrace_ops *set_function_trace_op; /* List for set_ftrace_pid's pids. */ LIST_HEAD(ftrace_pids); @@ -278,6 +280,29 @@ static void update_global_ops(void) global_ops.func = func; } +static void ftrace_sync(struct work_struct *work) +{ + /* + * This function is just a stub to implement a hard force + * of synchronize_sched(). This requires synchronizing + * tasks even in userspace and idle. + * + * Yes, function tracing is rude. + */ +} + +static void ftrace_sync_ipi(void *data) +{ + /* Probably not needed, but do it anyway */ + smp_rmb(); +} + +#ifdef CONFIG_FUNCTION_GRAPH_TRACER +static void update_function_graph_func(void); +#else +static inline void update_function_graph_func(void) { } +#endif + static void update_ftrace_function(void) { ftrace_func_t func; @@ -296,16 +321,61 @@ static void update_ftrace_function(void) !FTRACE_FORCE_LIST_FUNC)) { /* Set the ftrace_ops that the arch callback uses */ if (ftrace_ops_list == &global_ops) - function_trace_op = ftrace_global_list; + set_function_trace_op = ftrace_global_list; else - function_trace_op = ftrace_ops_list; + set_function_trace_op = ftrace_ops_list; func = ftrace_ops_list->func; } else { /* Just use the default ftrace_ops */ - function_trace_op = &ftrace_list_end; + set_function_trace_op = &ftrace_list_end; func = ftrace_ops_list_func; } + /* If there's no change, then do nothing more here */ + if (ftrace_trace_function == func) + return; + + update_function_graph_func(); + + /* + * If we are using the list function, it doesn't care + * about the function_trace_ops. + */ + if (func == ftrace_ops_list_func) { + ftrace_trace_function = func; + /* + * Don't even bother setting function_trace_ops, + * it would be racy to do so anyway. + */ + return; + } + +#ifndef CONFIG_DYNAMIC_FTRACE + /* + * For static tracing, we need to be a bit more careful. + * The function change takes affect immediately. Thus, + * we need to coorditate the setting of the function_trace_ops + * with the setting of the ftrace_trace_function. + * + * Set the function to the list ops, which will call the + * function we want, albeit indirectly, but it handles the + * ftrace_ops and doesn't depend on function_trace_op. + */ + ftrace_trace_function = ftrace_ops_list_func; + /* + * Make sure all CPUs see this. Yes this is slow, but static + * tracing is slow and nasty to have enabled. + */ + schedule_on_each_cpu(ftrace_sync); + /* Now all cpus are using the list ops. */ + function_trace_op = set_function_trace_op; + /* Make sure the function_trace_op is visible on all CPUs */ + smp_wmb(); + /* Nasty way to force a rmb on all cpus */ + smp_call_function(ftrace_sync_ipi, NULL, 1); + /* OK, we are all set to update the ftrace_trace_function now! */ +#endif /* !CONFIG_DYNAMIC_FTRACE */ + ftrace_trace_function = func; } @@ -410,17 +480,6 @@ static int __register_ftrace_function(struct ftrace_ops *ops) return 0; } -static void ftrace_sync(struct work_struct *work) -{ - /* - * This function is just a stub to implement a hard force - * of synchronize_sched(). This requires synchronizing - * tasks even in userspace and idle. - * - * Yes, function tracing is rude. - */ -} - static int __unregister_ftrace_function(struct ftrace_ops *ops) { int ret; @@ -439,20 +498,6 @@ static int __unregister_ftrace_function(struct ftrace_ops *ops) } else if (ops->flags & FTRACE_OPS_FL_CONTROL) { ret = remove_ftrace_list_ops(&ftrace_control_list, &control_ops, ops); - if (!ret) { - /* - * The ftrace_ops is now removed from the list, - * so there'll be no new users. We must ensure - * all current users are done before we free - * the control data. - * Note synchronize_sched() is not enough, as we - * use preempt_disable() to do RCU, but the function - * tracer can be called where RCU is not active - * (before user_exit()). - */ - schedule_on_each_cpu(ftrace_sync); - control_ops_free(ops); - } } else ret = remove_ftrace_ops(&ftrace_ops_list, ops); @@ -462,17 +507,6 @@ static int __unregister_ftrace_function(struct ftrace_ops *ops) if (ftrace_enabled) update_ftrace_function(); - /* - * Dynamic ops may be freed, we must make sure that all - * callers are done before leaving this function. - * - * Again, normal synchronize_sched() is not good enough. - * We need to do a hard force of sched synchronization. - */ - if (ops->flags & FTRACE_OPS_FL_DYNAMIC) - schedule_on_each_cpu(ftrace_sync); - - return 0; } @@ -1082,19 +1116,6 @@ static __init void ftrace_profile_debugfs(struct dentry *d_tracer) static struct pid * const ftrace_swapper_pid = &init_struct_pid; -loff_t -ftrace_filter_lseek(struct file *file, loff_t offset, int whence) -{ - loff_t ret; - - if (file->f_mode & FMODE_READ) - ret = seq_lseek(file, offset, whence); - else - file->f_pos = ret = 1; - - return ret; -} - #ifdef CONFIG_DYNAMIC_FTRACE #ifndef CONFIG_FTRACE_MCOUNT_RECORD @@ -1992,8 +2013,14 @@ void ftrace_modify_all_code(int command) else if (command & FTRACE_DISABLE_CALLS) ftrace_replace_code(0); - if (update && ftrace_trace_function != ftrace_ops_list_func) + if (update && ftrace_trace_function != ftrace_ops_list_func) { + function_trace_op = set_function_trace_op; + smp_wmb(); + /* If irqs are disabled, we are in stop machine */ + if (!irqs_disabled()) + smp_call_function(ftrace_sync_ipi, NULL, 1); ftrace_update_ftrace_func(ftrace_trace_function); + } if (command & FTRACE_START_FUNC_RET) ftrace_enable_ftrace_graph_caller(); @@ -2156,10 +2183,41 @@ static int ftrace_shutdown(struct ftrace_ops *ops, int command) command |= FTRACE_UPDATE_TRACE_FUNC; } - if (!command || !ftrace_enabled) + if (!command || !ftrace_enabled) { + /* + * If these are control ops, they still need their + * per_cpu field freed. Since, function tracing is + * not currently active, we can just free them + * without synchronizing all CPUs. + */ + if (ops->flags & FTRACE_OPS_FL_CONTROL) + control_ops_free(ops); return 0; + } ftrace_run_update_code(command); + + /* + * Dynamic ops may be freed, we must make sure that all + * callers are done before leaving this function. + * The same goes for freeing the per_cpu data of the control + * ops. + * + * Again, normal synchronize_sched() is not good enough. + * We need to do a hard force of sched synchronization. + * This is because we use preempt_disable() to do RCU, but + * the function tracers can be called where RCU is not watching + * (like before user_exit()). We can not rely on the RCU + * infrastructure to do the synchronization, thus we must do it + * ourselves. + */ + if (ops->flags & (FTRACE_OPS_FL_DYNAMIC | FTRACE_OPS_FL_CONTROL)) { + schedule_on_each_cpu(ftrace_sync); + + if (ops->flags & FTRACE_OPS_FL_CONTROL) + control_ops_free(ops); + } + return 0; } @@ -2739,7 +2797,7 @@ static void ftrace_filter_reset(struct ftrace_hash *hash) * routine, you can use ftrace_filter_write() for the write * routine if @flag has FTRACE_ITER_FILTER set, or * ftrace_notrace_write() if @flag has FTRACE_ITER_NOTRACE set. - * ftrace_filter_lseek() should be used as the lseek routine, and + * tracing_lseek() should be used as the lseek routine, and * release must call ftrace_regex_release(). */ int @@ -3767,7 +3825,7 @@ static const struct file_operations ftrace_filter_fops = { .open = ftrace_filter_open, .read = seq_read, .write = ftrace_filter_write, - .llseek = ftrace_filter_lseek, + .llseek = tracing_lseek, .release = ftrace_regex_release, }; @@ -3775,7 +3833,7 @@ static const struct file_operations ftrace_notrace_fops = { .open = ftrace_notrace_open, .read = seq_read, .write = ftrace_notrace_write, - .llseek = ftrace_filter_lseek, + .llseek = tracing_lseek, .release = ftrace_regex_release, }; @@ -4038,7 +4096,7 @@ static const struct file_operations ftrace_graph_fops = { .open = ftrace_graph_open, .read = seq_read, .write = ftrace_graph_write, - .llseek = ftrace_filter_lseek, + .llseek = tracing_lseek, .release = ftrace_graph_release, }; @@ -4046,7 +4104,7 @@ static const struct file_operations ftrace_graph_notrace_fops = { .open = ftrace_graph_notrace_open, .read = seq_read, .write = ftrace_graph_write, - .llseek = ftrace_filter_lseek, + .llseek = tracing_lseek, .release = ftrace_graph_release, }; #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ @@ -4719,7 +4777,7 @@ static const struct file_operations ftrace_pid_fops = { .open = ftrace_pid_open, .write = ftrace_pid_write, .read = seq_read, - .llseek = ftrace_filter_lseek, + .llseek = tracing_lseek, .release = ftrace_pid_release, }; @@ -4862,6 +4920,7 @@ int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace) trace_func_graph_ret_t ftrace_graph_return = (trace_func_graph_ret_t)ftrace_stub; trace_func_graph_ent_t ftrace_graph_entry = ftrace_graph_entry_stub; +static trace_func_graph_ent_t __ftrace_graph_entry = ftrace_graph_entry_stub; /* Try to assign a return stack array on FTRACE_RETSTACK_ALLOC_SIZE tasks. */ static int alloc_retstack_tasklist(struct ftrace_ret_stack **ret_stack_list) @@ -5003,6 +5062,30 @@ static struct ftrace_ops fgraph_ops __read_mostly = { FTRACE_OPS_FL_RECURSION_SAFE, }; +static int ftrace_graph_entry_test(struct ftrace_graph_ent *trace) +{ + if (!ftrace_ops_test(&global_ops, trace->func, NULL)) + return 0; + return __ftrace_graph_entry(trace); +} + +/* + * The function graph tracer should only trace the functions defined + * by set_ftrace_filter and set_ftrace_notrace. If another function + * tracer ops is registered, the graph tracer requires testing the + * function against the global ops, and not just trace any function + * that any ftrace_ops registered. + */ +static void update_function_graph_func(void) +{ + if (ftrace_ops_list == &ftrace_list_end || + (ftrace_ops_list == &global_ops && + global_ops.next == &ftrace_list_end)) + ftrace_graph_entry = __ftrace_graph_entry; + else + ftrace_graph_entry = ftrace_graph_entry_test; +} + int register_ftrace_graph(trace_func_graph_ret_t retfunc, trace_func_graph_ent_t entryfunc) { @@ -5027,7 +5110,16 @@ int register_ftrace_graph(trace_func_graph_ret_t retfunc, } ftrace_graph_return = retfunc; - ftrace_graph_entry = entryfunc; + + /* + * Update the indirect function to the entryfunc, and the + * function that gets called to the entry_test first. Then + * call the update fgraph entry function to determine if + * the entryfunc should be called directly or not. + */ + __ftrace_graph_entry = entryfunc; + ftrace_graph_entry = ftrace_graph_entry_test; + update_function_graph_func(); ret = ftrace_startup(&fgraph_ops, FTRACE_START_FUNC_RET); @@ -5046,6 +5138,7 @@ void unregister_ftrace_graph(void) ftrace_graph_active--; ftrace_graph_return = (trace_func_graph_ret_t)ftrace_stub; ftrace_graph_entry = ftrace_graph_entry_stub; + __ftrace_graph_entry = ftrace_graph_entry_stub; ftrace_shutdown(&fgraph_ops, FTRACE_STOP_FUNC_RET); unregister_pm_notifier(&ftrace_suspend_notifier); unregister_trace_sched_switch(ftrace_graph_probe_sched_switch, NULL); diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 9d20cd9..20c755e 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -595,6 +595,28 @@ void free_snapshot(struct trace_array *tr) } /** + * tracing_alloc_snapshot - allocate snapshot buffer. + * + * This only allocates the snapshot buffer if it isn't already + * allocated - it doesn't also take a snapshot. + * + * This is meant to be used in cases where the snapshot buffer needs + * to be set up for events that can't sleep but need to be able to + * trigger a snapshot. + */ +int tracing_alloc_snapshot(void) +{ + struct trace_array *tr = &global_trace; + int ret; + + ret = alloc_snapshot(tr); + WARN_ON(ret < 0); + + return ret; +} +EXPORT_SYMBOL_GPL(tracing_alloc_snapshot); + +/** * trace_snapshot_alloc - allocate and take a snapshot of the current buffer. * * This is similar to trace_snapshot(), but it will allocate the @@ -607,11 +629,10 @@ void free_snapshot(struct trace_array *tr) */ void tracing_snapshot_alloc(void) { - struct trace_array *tr = &global_trace; int ret; - ret = alloc_snapshot(tr); - if (WARN_ON(ret < 0)) + ret = tracing_alloc_snapshot(); + if (ret < 0) return; tracing_snapshot(); @@ -623,6 +644,12 @@ void tracing_snapshot(void) WARN_ONCE(1, "Snapshot feature not enabled, but internal snapshot used"); } EXPORT_SYMBOL_GPL(tracing_snapshot); +int tracing_alloc_snapshot(void) +{ + WARN_ONCE(1, "Snapshot feature not enabled, but snapshot allocation used"); + return -ENODEV; +} +EXPORT_SYMBOL_GPL(tracing_alloc_snapshot); void tracing_snapshot_alloc(void) { /* Give warning */ @@ -3156,19 +3183,23 @@ tracing_write_stub(struct file *filp, const char __user *ubuf, return count; } -static loff_t tracing_seek(struct file *file, loff_t offset, int origin) +loff_t tracing_lseek(struct file *file, loff_t offset, int whence) { + int ret; + if (file->f_mode & FMODE_READ) - return seq_lseek(file, offset, origin); + ret = seq_lseek(file, offset, whence); else - return 0; + file->f_pos = ret = 0; + + return ret; } static const struct file_operations tracing_fops = { .open = tracing_open, .read = seq_read, .write = tracing_write_stub, - .llseek = tracing_seek, + .llseek = tracing_lseek, .release = tracing_release, }; @@ -4212,12 +4243,6 @@ out: return sret; } -static void tracing_pipe_buf_release(struct pipe_inode_info *pipe, - struct pipe_buffer *buf) -{ - __free_page(buf->page); -} - static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, unsigned int idx) { @@ -4229,7 +4254,7 @@ static const struct pipe_buf_operations tracing_pipe_buf_ops = { .map = generic_pipe_buf_map, .unmap = generic_pipe_buf_unmap, .confirm = generic_pipe_buf_confirm, - .release = tracing_pipe_buf_release, + .release = generic_pipe_buf_release, .steal = generic_pipe_buf_steal, .get = generic_pipe_buf_get, }; @@ -4913,7 +4938,7 @@ static const struct file_operations snapshot_fops = { .open = tracing_snapshot_open, .read = seq_read, .write = tracing_snapshot_write, - .llseek = tracing_seek, + .llseek = tracing_lseek, .release = tracing_snapshot_release, }; @@ -5883,6 +5908,8 @@ allocate_trace_buffer(struct trace_array *tr, struct trace_buffer *buf, int size rb_flags = trace_flags & TRACE_ITER_OVERWRITE ? RB_FL_OVERWRITE : 0; + buf->tr = tr; + buf->buffer = ring_buffer_alloc(size, rb_flags); if (!buf->buffer) return -ENOMEM; diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index ea189e0..02b592f 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -1,3 +1,4 @@ + #ifndef _LINUX_KERNEL_TRACE_H #define _LINUX_KERNEL_TRACE_H @@ -587,6 +588,8 @@ void tracing_start_sched_switch_record(void); int register_tracer(struct tracer *type); int is_tracing_stopped(void); +loff_t tracing_lseek(struct file *file, loff_t offset, int whence); + extern cpumask_var_t __read_mostly tracing_buffer_mask; #define for_each_tracing_cpu(cpu) \ @@ -1020,6 +1023,10 @@ extern int apply_subsystem_event_filter(struct ftrace_subsystem_dir *dir, extern void print_subsystem_event_filter(struct event_subsystem *system, struct trace_seq *s); extern int filter_assign_type(const char *type); +extern int create_event_filter(struct ftrace_event_call *call, + char *filter_str, bool set_str, + struct event_filter **filterp); +extern void free_event_filter(struct event_filter *filter); struct ftrace_event_field * trace_find_event_field(struct ftrace_event_call *call, char *name); @@ -1028,9 +1035,195 @@ extern void trace_event_enable_cmd_record(bool enable); extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr); extern int event_trace_del_tracer(struct trace_array *tr); +extern struct ftrace_event_file *find_event_file(struct trace_array *tr, + const char *system, + const char *event); + +static inline void *event_file_data(struct file *filp) +{ + return ACCESS_ONCE(file_inode(filp)->i_private); +} + extern struct mutex event_mutex; extern struct list_head ftrace_events; +extern const struct file_operations event_trigger_fops; + +extern int register_trigger_cmds(void); +extern void clear_event_triggers(struct trace_array *tr); + +struct event_trigger_data { + unsigned long count; + int ref; + struct event_trigger_ops *ops; + struct event_command *cmd_ops; + struct event_filter __rcu *filter; + char *filter_str; + void *private_data; + struct list_head list; +}; + +/** + * struct event_trigger_ops - callbacks for trace event triggers + * + * The methods in this structure provide per-event trigger hooks for + * various trigger operations. + * + * All the methods below, except for @init() and @free(), must be + * implemented. + * + * @func: The trigger 'probe' function called when the triggering + * event occurs. The data passed into this callback is the data + * that was supplied to the event_command @reg() function that + * registered the trigger (see struct event_command). + * + * @init: An optional initialization function called for the trigger + * when the trigger is registered (via the event_command reg() + * function). This can be used to perform per-trigger + * initialization such as incrementing a per-trigger reference + * count, for instance. This is usually implemented by the + * generic utility function @event_trigger_init() (see + * trace_event_triggers.c). + * + * @free: An optional de-initialization function called for the + * trigger when the trigger is unregistered (via the + * event_command @reg() function). This can be used to perform + * per-trigger de-initialization such as decrementing a + * per-trigger reference count and freeing corresponding trigger + * data, for instance. This is usually implemented by the + * generic utility function @event_trigger_free() (see + * trace_event_triggers.c). + * + * @print: The callback function invoked to have the trigger print + * itself. This is usually implemented by a wrapper function + * that calls the generic utility function @event_trigger_print() + * (see trace_event_triggers.c). + */ +struct event_trigger_ops { + void (*func)(struct event_trigger_data *data); + int (*init)(struct event_trigger_ops *ops, + struct event_trigger_data *data); + void (*free)(struct event_trigger_ops *ops, + struct event_trigger_data *data); + int (*print)(struct seq_file *m, + struct event_trigger_ops *ops, + struct event_trigger_data *data); +}; + +/** + * struct event_command - callbacks and data members for event commands + * + * Event commands are invoked by users by writing the command name + * into the 'trigger' file associated with a trace event. The + * parameters associated with a specific invocation of an event + * command are used to create an event trigger instance, which is + * added to the list of trigger instances associated with that trace + * event. When the event is hit, the set of triggers associated with + * that event is invoked. + * + * The data members in this structure provide per-event command data + * for various event commands. + * + * All the data members below, except for @post_trigger, must be set + * for each event command. + * + * @name: The unique name that identifies the event command. This is + * the name used when setting triggers via trigger files. + * + * @trigger_type: A unique id that identifies the event command + * 'type'. This value has two purposes, the first to ensure that + * only one trigger of the same type can be set at a given time + * for a particular event e.g. it doesn't make sense to have both + * a traceon and traceoff trigger attached to a single event at + * the same time, so traceon and traceoff have the same type + * though they have different names. The @trigger_type value is + * also used as a bit value for deferring the actual trigger + * action until after the current event is finished. Some + * commands need to do this if they themselves log to the trace + * buffer (see the @post_trigger() member below). @trigger_type + * values are defined by adding new values to the trigger_type + * enum in include/linux/ftrace_event.h. + * + * @post_trigger: A flag that says whether or not this command needs + * to have its action delayed until after the current event has + * been closed. Some triggers need to avoid being invoked while + * an event is currently in the process of being logged, since + * the trigger may itself log data into the trace buffer. Thus + * we make sure the current event is committed before invoking + * those triggers. To do that, the trigger invocation is split + * in two - the first part checks the filter using the current + * trace record; if a command has the @post_trigger flag set, it + * sets a bit for itself in the return value, otherwise it + * directly invokes the trigger. Once all commands have been + * either invoked or set their return flag, the current record is + * either committed or discarded. At that point, if any commands + * have deferred their triggers, those commands are finally + * invoked following the close of the current event. In other + * words, if the event_trigger_ops @func() probe implementation + * itself logs to the trace buffer, this flag should be set, + * otherwise it can be left unspecified. + * + * All the methods below, except for @set_filter(), must be + * implemented. + * + * @func: The callback function responsible for parsing and + * registering the trigger written to the 'trigger' file by the + * user. It allocates the trigger instance and registers it with + * the appropriate trace event. It makes use of the other + * event_command callback functions to orchestrate this, and is + * usually implemented by the generic utility function + * @event_trigger_callback() (see trace_event_triggers.c). + * + * @reg: Adds the trigger to the list of triggers associated with the + * event, and enables the event trigger itself, after + * initializing it (via the event_trigger_ops @init() function). + * This is also where commands can use the @trigger_type value to + * make the decision as to whether or not multiple instances of + * the trigger should be allowed. This is usually implemented by + * the generic utility function @register_trigger() (see + * trace_event_triggers.c). + * + * @unreg: Removes the trigger from the list of triggers associated + * with the event, and disables the event trigger itself, after + * initializing it (via the event_trigger_ops @free() function). + * This is usually implemented by the generic utility function + * @unregister_trigger() (see trace_event_triggers.c). + * + * @set_filter: An optional function called to parse and set a filter + * for the trigger. If no @set_filter() method is set for the + * event command, filters set by the user for the command will be + * ignored. This is usually implemented by the generic utility + * function @set_trigger_filter() (see trace_event_triggers.c). + * + * @get_trigger_ops: The callback function invoked to retrieve the + * event_trigger_ops implementation associated with the command. + */ +struct event_command { + struct list_head list; + char *name; + enum event_trigger_type trigger_type; + bool post_trigger; + int (*func)(struct event_command *cmd_ops, + struct ftrace_event_file *file, + char *glob, char *cmd, char *params); + int (*reg)(char *glob, + struct event_trigger_ops *ops, + struct event_trigger_data *data, + struct ftrace_event_file *file); + void (*unreg)(char *glob, + struct event_trigger_ops *ops, + struct event_trigger_data *data, + struct ftrace_event_file *file); + int (*set_filter)(char *filter_str, + struct event_trigger_data *data, + struct ftrace_event_file *file); + struct event_trigger_ops *(*get_trigger_ops)(char *cmd, char *param); +}; + +extern int trace_event_enable_disable(struct ftrace_event_file *file, + int enable, int soft_disable); +extern int tracing_alloc_snapshot(void); + extern const char *__start___trace_bprintk_fmt[]; extern const char *__stop___trace_bprintk_fmt[]; diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index a11800a..e71ffd4 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -342,6 +342,12 @@ static int __ftrace_event_enable_disable(struct ftrace_event_file *file, return ret; } +int trace_event_enable_disable(struct ftrace_event_file *file, + int enable, int soft_disable) +{ + return __ftrace_event_enable_disable(file, enable, soft_disable); +} + static int ftrace_event_enable_disable(struct ftrace_event_file *file, int enable) { @@ -421,11 +427,6 @@ static void remove_subsystem(struct ftrace_subsystem_dir *dir) } } -static void *event_file_data(struct file *filp) -{ - return ACCESS_ONCE(file_inode(filp)->i_private); -} - static void remove_event_file_dir(struct ftrace_event_file *file) { struct dentry *dir = file->dir; @@ -1549,6 +1550,9 @@ event_create_dir(struct dentry *parent, struct ftrace_event_file *file) trace_create_file("filter", 0644, file->dir, file, &ftrace_event_filter_fops); + trace_create_file("trigger", 0644, file->dir, file, + &event_trigger_fops); + trace_create_file("format", 0444, file->dir, call, &ftrace_event_format_fops); @@ -1645,6 +1649,8 @@ trace_create_new_event(struct ftrace_event_call *call, file->event_call = call; file->tr = tr; atomic_set(&file->sm_ref, 0); + atomic_set(&file->tm_ref, 0); + INIT_LIST_HEAD(&file->triggers); list_add(&file->list, &tr->events); return file; @@ -1849,20 +1855,7 @@ __trace_add_event_dirs(struct trace_array *tr) } } -#ifdef CONFIG_DYNAMIC_FTRACE - -/* Avoid typos */ -#define ENABLE_EVENT_STR "enable_event" -#define DISABLE_EVENT_STR "disable_event" - -struct event_probe_data { - struct ftrace_event_file *file; - unsigned long count; - int ref; - bool enable; -}; - -static struct ftrace_event_file * +struct ftrace_event_file * find_event_file(struct trace_array *tr, const char *system, const char *event) { struct ftrace_event_file *file; @@ -1885,6 +1878,19 @@ find_event_file(struct trace_array *tr, const char *system, const char *event) return NULL; } +#ifdef CONFIG_DYNAMIC_FTRACE + +/* Avoid typos */ +#define ENABLE_EVENT_STR "enable_event" +#define DISABLE_EVENT_STR "disable_event" + +struct event_probe_data { + struct ftrace_event_file *file; + unsigned long count; + int ref; + bool enable; +}; + static void event_enable_probe(unsigned long ip, unsigned long parent_ip, void **_data) { @@ -2311,6 +2317,9 @@ int event_trace_del_tracer(struct trace_array *tr) { mutex_lock(&event_mutex); + /* Disable any event triggers and associated soft-disabled events */ + clear_event_triggers(tr); + /* Disable any running events */ __ftrace_set_clr_event_nolock(tr, NULL, NULL, NULL, 0); @@ -2377,6 +2386,8 @@ static __init int event_trace_enable(void) register_event_cmds(); + register_trigger_cmds(); + return 0; } diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c index 2468f56..8a86319 100644 --- a/kernel/trace/trace_events_filter.c +++ b/kernel/trace/trace_events_filter.c @@ -799,6 +799,11 @@ static void __free_filter(struct event_filter *filter) kfree(filter); } +void free_event_filter(struct event_filter *filter) +{ + __free_filter(filter); +} + void destroy_call_preds(struct ftrace_event_call *call) { __free_filter(call->filter); @@ -1938,6 +1943,13 @@ static int create_filter(struct ftrace_event_call *call, return err; } +int create_event_filter(struct ftrace_event_call *call, + char *filter_str, bool set_str, + struct event_filter **filterp) +{ + return create_filter(call, filter_str, set_str, filterp); +} + /** * create_system_filter - create a filter for an event_subsystem * @system: event_subsystem to create a filter for diff --git a/kernel/trace/trace_events_trigger.c b/kernel/trace/trace_events_trigger.c new file mode 100644 index 0000000..8efbb69 --- /dev/null +++ b/kernel/trace/trace_events_trigger.c @@ -0,0 +1,1437 @@ +/* + * trace_events_trigger - trace event triggers + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + * + * Copyright (C) 2013 Tom Zanussi <tom.zanussi@linux.intel.com> + */ + +#include <linux/module.h> +#include <linux/ctype.h> +#include <linux/mutex.h> +#include <linux/slab.h> + +#include "trace.h" + +static LIST_HEAD(trigger_commands); +static DEFINE_MUTEX(trigger_cmd_mutex); + +static void +trigger_data_free(struct event_trigger_data *data) +{ + if (data->cmd_ops->set_filter) + data->cmd_ops->set_filter(NULL, data, NULL); + + synchronize_sched(); /* make sure current triggers exit before free */ + kfree(data); +} + +/** + * event_triggers_call - Call triggers associated with a trace event + * @file: The ftrace_event_file associated with the event + * @rec: The trace entry for the event, NULL for unconditional invocation + * + * For each trigger associated with an event, invoke the trigger + * function registered with the associated trigger command. If rec is + * non-NULL, it means that the trigger requires further processing and + * shouldn't be unconditionally invoked. If rec is non-NULL and the + * trigger has a filter associated with it, rec will checked against + * the filter and if the record matches the trigger will be invoked. + * If the trigger is a 'post_trigger', meaning it shouldn't be invoked + * in any case until the current event is written, the trigger + * function isn't invoked but the bit associated with the deferred + * trigger is set in the return value. + * + * Returns an enum event_trigger_type value containing a set bit for + * any trigger that should be deferred, ETT_NONE if nothing to defer. + * + * Called from tracepoint handlers (with rcu_read_lock_sched() held). + * + * Return: an enum event_trigger_type value containing a set bit for + * any trigger that should be deferred, ETT_NONE if nothing to defer. + */ +enum event_trigger_type +event_triggers_call(struct ftrace_event_file *file, void *rec) +{ + struct event_trigger_data *data; + enum event_trigger_type tt = ETT_NONE; + struct event_filter *filter; + + if (list_empty(&file->triggers)) + return tt; + + list_for_each_entry_rcu(data, &file->triggers, list) { + if (!rec) { + data->ops->func(data); + continue; + } + filter = rcu_dereference(data->filter); + if (filter && !filter_match_preds(filter, rec)) + continue; + if (data->cmd_ops->post_trigger) { + tt |= data->cmd_ops->trigger_type; + continue; + } + data->ops->func(data); + } + return tt; +} +EXPORT_SYMBOL_GPL(event_triggers_call); + +/** + * event_triggers_post_call - Call 'post_triggers' for a trace event + * @file: The ftrace_event_file associated with the event + * @tt: enum event_trigger_type containing a set bit for each trigger to invoke + * + * For each trigger associated with an event, invoke the trigger + * function registered with the associated trigger command, if the + * corresponding bit is set in the tt enum passed into this function. + * See @event_triggers_call for details on how those bits are set. + * + * Called from tracepoint handlers (with rcu_read_lock_sched() held). + */ +void +event_triggers_post_call(struct ftrace_event_file *file, + enum event_trigger_type tt) +{ + struct event_trigger_data *data; + + list_for_each_entry_rcu(data, &file->triggers, list) { + if (data->cmd_ops->trigger_type & tt) + data->ops->func(data); + } +} +EXPORT_SYMBOL_GPL(event_triggers_post_call); + +#define SHOW_AVAILABLE_TRIGGERS (void *)(1UL) + +static void *trigger_next(struct seq_file *m, void *t, loff_t *pos) +{ + struct ftrace_event_file *event_file = event_file_data(m->private); + + if (t == SHOW_AVAILABLE_TRIGGERS) + return NULL; + + return seq_list_next(t, &event_file->triggers, pos); +} + +static void *trigger_start(struct seq_file *m, loff_t *pos) +{ + struct ftrace_event_file *event_file; + + /* ->stop() is called even if ->start() fails */ + mutex_lock(&event_mutex); + event_file = event_file_data(m->private); + if (unlikely(!event_file)) + return ERR_PTR(-ENODEV); + + if (list_empty(&event_file->triggers)) + return *pos == 0 ? SHOW_AVAILABLE_TRIGGERS : NULL; + + return seq_list_start(&event_file->triggers, *pos); +} + +static void trigger_stop(struct seq_file *m, void *t) +{ + mutex_unlock(&event_mutex); +} + +static int trigger_show(struct seq_file *m, void *v) +{ + struct event_trigger_data *data; + struct event_command *p; + + if (v == SHOW_AVAILABLE_TRIGGERS) { + seq_puts(m, "# Available triggers:\n"); + seq_putc(m, '#'); + mutex_lock(&trigger_cmd_mutex); + list_for_each_entry_reverse(p, &trigger_commands, list) + seq_printf(m, " %s", p->name); + seq_putc(m, '\n'); + mutex_unlock(&trigger_cmd_mutex); + return 0; + } + + data = list_entry(v, struct event_trigger_data, list); + data->ops->print(m, data->ops, data); + + return 0; +} + +static const struct seq_operations event_triggers_seq_ops = { + .start = trigger_start, + .next = trigger_next, + .stop = trigger_stop, + .show = trigger_show, +}; + +static int event_trigger_regex_open(struct inode *inode, struct file *file) +{ + int ret = 0; + + mutex_lock(&event_mutex); + + if (unlikely(!event_file_data(file))) { + mutex_unlock(&event_mutex); + return -ENODEV; + } + + if (file->f_mode & FMODE_READ) { + ret = seq_open(file, &event_triggers_seq_ops); + if (!ret) { + struct seq_file *m = file->private_data; + m->private = file; + } + } + + mutex_unlock(&event_mutex); + + return ret; +} + +static int trigger_process_regex(struct ftrace_event_file *file, char *buff) +{ + char *command, *next = buff; + struct event_command *p; + int ret = -EINVAL; + + command = strsep(&next, ": \t"); + command = (command[0] != '!') ? command : command + 1; + + mutex_lock(&trigger_cmd_mutex); + list_for_each_entry(p, &trigger_commands, list) { + if (strcmp(p->name, command) == 0) { + ret = p->func(p, file, buff, command, next); + goto out_unlock; + } + } + out_unlock: + mutex_unlock(&trigger_cmd_mutex); + + return ret; +} + +static ssize_t event_trigger_regex_write(struct file *file, + const char __user *ubuf, + size_t cnt, loff_t *ppos) +{ + struct ftrace_event_file *event_file; + ssize_t ret; + char *buf; + + if (!cnt) + return 0; + + if (cnt >= PAGE_SIZE) + return -EINVAL; + + buf = (char *)__get_free_page(GFP_TEMPORARY); + if (!buf) + return -ENOMEM; + + if (copy_from_user(buf, ubuf, cnt)) { + free_page((unsigned long)buf); + return -EFAULT; + } + buf[cnt] = '\0'; + strim(buf); + + mutex_lock(&event_mutex); + event_file = event_file_data(file); + if (unlikely(!event_file)) { + mutex_unlock(&event_mutex); + free_page((unsigned long)buf); + return -ENODEV; + } + ret = trigger_process_regex(event_file, buf); + mutex_unlock(&event_mutex); + + free_page((unsigned long)buf); + if (ret < 0) + goto out; + + *ppos += cnt; + ret = cnt; + out: + return ret; +} + +static int event_trigger_regex_release(struct inode *inode, struct file *file) +{ + mutex_lock(&event_mutex); + + if (file->f_mode & FMODE_READ) + seq_release(inode, file); + + mutex_unlock(&event_mutex); + + return 0; +} + +static ssize_t +event_trigger_write(struct file *filp, const char __user *ubuf, + size_t cnt, loff_t *ppos) +{ + return event_trigger_regex_write(filp, ubuf, cnt, ppos); +} + +static int +event_trigger_open(struct inode *inode, struct file *filp) +{ + return event_trigger_regex_open(inode, filp); +} + +static int +event_trigger_release(struct inode *inode, struct file *file) +{ + return event_trigger_regex_release(inode, file); +} + +const struct file_operations event_trigger_fops = { + .open = event_trigger_open, + .read = seq_read, + .write = event_trigger_write, + .llseek = tracing_lseek, + .release = event_trigger_release, +}; + +/* + * Currently we only register event commands from __init, so mark this + * __init too. + */ +static __init int register_event_command(struct event_command *cmd) +{ + struct event_command *p; + int ret = 0; + + mutex_lock(&trigger_cmd_mutex); + list_for_each_entry(p, &trigger_commands, list) { + if (strcmp(cmd->name, p->name) == 0) { + ret = -EBUSY; + goto out_unlock; + } + } + list_add(&cmd->list, &trigger_commands); + out_unlock: + mutex_unlock(&trigger_cmd_mutex); + + return ret; +} + +/* + * Currently we only unregister event commands from __init, so mark + * this __init too. + */ +static __init int unregister_event_command(struct event_command *cmd) +{ + struct event_command *p, *n; + int ret = -ENODEV; + + mutex_lock(&trigger_cmd_mutex); + list_for_each_entry_safe(p, n, &trigger_commands, list) { + if (strcmp(cmd->name, p->name) == 0) { + ret = 0; + list_del_init(&p->list); + goto out_unlock; + } + } + out_unlock: + mutex_unlock(&trigger_cmd_mutex); + + return ret; +} + +/** + * event_trigger_print - Generic event_trigger_ops @print implementation + * @name: The name of the event trigger + * @m: The seq_file being printed to + * @data: Trigger-specific data + * @filter_str: filter_str to print, if present + * + * Common implementation for event triggers to print themselves. + * + * Usually wrapped by a function that simply sets the @name of the + * trigger command and then invokes this. + * + * Return: 0 on success, errno otherwise + */ +static int +event_trigger_print(const char *name, struct seq_file *m, + void *data, char *filter_str) +{ + long count = (long)data; + + seq_printf(m, "%s", name); + + if (count == -1) + seq_puts(m, ":unlimited"); + else + seq_printf(m, ":count=%ld", count); + + if (filter_str) + seq_printf(m, " if %s\n", filter_str); + else + seq_puts(m, "\n"); + + return 0; +} + +/** + * event_trigger_init - Generic event_trigger_ops @init implementation + * @ops: The trigger ops associated with the trigger + * @data: Trigger-specific data + * + * Common implementation of event trigger initialization. + * + * Usually used directly as the @init method in event trigger + * implementations. + * + * Return: 0 on success, errno otherwise + */ +static int +event_trigger_init(struct event_trigger_ops *ops, + struct event_trigger_data *data) +{ + data->ref++; + return 0; +} + +/** + * event_trigger_free - Generic event_trigger_ops @free implementation + * @ops: The trigger ops associated with the trigger + * @data: Trigger-specific data + * + * Common implementation of event trigger de-initialization. + * + * Usually used directly as the @free method in event trigger + * implementations. + */ +static void +event_trigger_free(struct event_trigger_ops *ops, + struct event_trigger_data *data) +{ + if (WARN_ON_ONCE(data->ref <= 0)) + return; + + data->ref--; + if (!data->ref) + trigger_data_free(data); +} + +static int trace_event_trigger_enable_disable(struct ftrace_event_file *file, + int trigger_enable) +{ + int ret = 0; + + if (trigger_enable) { + if (atomic_inc_return(&file->tm_ref) > 1) + return ret; + set_bit(FTRACE_EVENT_FL_TRIGGER_MODE_BIT, &file->flags); + ret = trace_event_enable_disable(file, 1, 1); + } else { + if (atomic_dec_return(&file->tm_ref) > 0) + return ret; + clear_bit(FTRACE_EVENT_FL_TRIGGER_MODE_BIT, &file->flags); + ret = trace_event_enable_disable(file, 0, 1); + } + + return ret; +} + +/** + * clear_event_triggers - Clear all triggers associated with a trace array + * @tr: The trace array to clear + * + * For each trigger, the triggering event has its tm_ref decremented + * via trace_event_trigger_enable_disable(), and any associated event + * (in the case of enable/disable_event triggers) will have its sm_ref + * decremented via free()->trace_event_enable_disable(). That + * combination effectively reverses the soft-mode/trigger state added + * by trigger registration. + * + * Must be called with event_mutex held. + */ +void +clear_event_triggers(struct trace_array *tr) +{ + struct ftrace_event_file *file; + + list_for_each_entry(file, &tr->events, list) { + struct event_trigger_data *data; + list_for_each_entry_rcu(data, &file->triggers, list) { + trace_event_trigger_enable_disable(file, 0); + if (data->ops->free) + data->ops->free(data->ops, data); + } + } +} + +/** + * update_cond_flag - Set or reset the TRIGGER_COND bit + * @file: The ftrace_event_file associated with the event + * + * If an event has triggers and any of those triggers has a filter or + * a post_trigger, trigger invocation needs to be deferred until after + * the current event has logged its data, and the event should have + * its TRIGGER_COND bit set, otherwise the TRIGGER_COND bit should be + * cleared. + */ +static void update_cond_flag(struct ftrace_event_file *file) +{ + struct event_trigger_data *data; + bool set_cond = false; + + list_for_each_entry_rcu(data, &file->triggers, list) { + if (data->filter || data->cmd_ops->post_trigger) { + set_cond = true; + break; + } + } + + if (set_cond) + set_bit(FTRACE_EVENT_FL_TRIGGER_COND_BIT, &file->flags); + else + clear_bit(FTRACE_EVENT_FL_TRIGGER_COND_BIT, &file->flags); +} + +/** + * register_trigger - Generic event_command @reg implementation + * @glob: The raw string used to register the trigger + * @ops: The trigger ops associated with the trigger + * @data: Trigger-specific data to associate with the trigger + * @file: The ftrace_event_file associated with the event + * + * Common implementation for event trigger registration. + * + * Usually used directly as the @reg method in event command + * implementations. + * + * Return: 0 on success, errno otherwise + */ +static int register_trigger(char *glob, struct event_trigger_ops *ops, + struct event_trigger_data *data, + struct ftrace_event_file *file) +{ + struct event_trigger_data *test; + int ret = 0; + + list_for_each_entry_rcu(test, &file->triggers, list) { + if (test->cmd_ops->trigger_type == data->cmd_ops->trigger_type) { + ret = -EEXIST; + goto out; + } + } + + if (data->ops->init) { + ret = data->ops->init(data->ops, data); + if (ret < 0) + goto out; + } + + list_add_rcu(&data->list, &file->triggers); + ret++; + + if (trace_event_trigger_enable_disable(file, 1) < 0) { + list_del_rcu(&data->list); + ret--; + } + update_cond_flag(file); +out: + return ret; +} + +/** + * unregister_trigger - Generic event_command @unreg implementation + * @glob: The raw string used to register the trigger + * @ops: The trigger ops associated with the trigger + * @test: Trigger-specific data used to find the trigger to remove + * @file: The ftrace_event_file associated with the event + * + * Common implementation for event trigger unregistration. + * + * Usually used directly as the @unreg method in event command + * implementations. + */ +static void unregister_trigger(char *glob, struct event_trigger_ops *ops, + struct event_trigger_data *test, + struct ftrace_event_file *file) +{ + struct event_trigger_data *data; + bool unregistered = false; + + list_for_each_entry_rcu(data, &file->triggers, list) { + if (data->cmd_ops->trigger_type == test->cmd_ops->trigger_type) { + unregistered = true; + list_del_rcu(&data->list); + update_cond_flag(file); + trace_event_trigger_enable_disable(file, 0); + break; + } + } + + if (unregistered && data->ops->free) + data->ops->free(data->ops, data); +} + +/** + * event_trigger_callback - Generic event_command @func implementation + * @cmd_ops: The command ops, used for trigger registration + * @file: The ftrace_event_file associated with the event + * @glob: The raw string used to register the trigger + * @cmd: The cmd portion of the string used to register the trigger + * @param: The params portion of the string used to register the trigger + * + * Common implementation for event command parsing and trigger + * instantiation. + * + * Usually used directly as the @func method in event command + * implementations. + * + * Return: 0 on success, errno otherwise + */ +static int +event_trigger_callback(struct event_command *cmd_ops, + struct ftrace_event_file *file, + char *glob, char *cmd, char *param) +{ + struct event_trigger_data *trigger_data; + struct event_trigger_ops *trigger_ops; + char *trigger = NULL; + char *number; + int ret; + + /* separate the trigger from the filter (t:n [if filter]) */ + if (param && isdigit(param[0])) + trigger = strsep(¶m, " \t"); + + trigger_ops = cmd_ops->get_trigger_ops(cmd, trigger); + + ret = -ENOMEM; + trigger_data = kzalloc(sizeof(*trigger_data), GFP_KERNEL); + if (!trigger_data) + goto out; + + trigger_data->count = -1; + trigger_data->ops = trigger_ops; + trigger_data->cmd_ops = cmd_ops; + INIT_LIST_HEAD(&trigger_data->list); + + if (glob[0] == '!') { + cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file); + kfree(trigger_data); + ret = 0; + goto out; + } + + if (trigger) { + number = strsep(&trigger, ":"); + + ret = -EINVAL; + if (!strlen(number)) + goto out_free; + + /* + * We use the callback data field (which is a pointer) + * as our counter. + */ + ret = kstrtoul(number, 0, &trigger_data->count); + if (ret) + goto out_free; + } + + if (!param) /* if param is non-empty, it's supposed to be a filter */ + goto out_reg; + + if (!cmd_ops->set_filter) + goto out_reg; + + ret = cmd_ops->set_filter(param, trigger_data, file); + if (ret < 0) + goto out_free; + + out_reg: + ret = cmd_ops->reg(glob, trigger_ops, trigger_data, file); + /* + * The above returns on success the # of functions enabled, + * but if it didn't find any functions it returns zero. + * Consider no functions a failure too. + */ + if (!ret) { + ret = -ENOENT; + goto out_free; + } else if (ret < 0) + goto out_free; + ret = 0; + out: + return ret; + + out_free: + if (cmd_ops->set_filter) + cmd_ops->set_filter(NULL, trigger_data, NULL); + kfree(trigger_data); + goto out; +} + +/** + * set_trigger_filter - Generic event_command @set_filter implementation + * @filter_str: The filter string for the trigger, NULL to remove filter + * @trigger_data: Trigger-specific data + * @file: The ftrace_event_file associated with the event + * + * Common implementation for event command filter parsing and filter + * instantiation. + * + * Usually used directly as the @set_filter method in event command + * implementations. + * + * Also used to remove a filter (if filter_str = NULL). + * + * Return: 0 on success, errno otherwise + */ +static int set_trigger_filter(char *filter_str, + struct event_trigger_data *trigger_data, + struct ftrace_event_file *file) +{ + struct event_trigger_data *data = trigger_data; + struct event_filter *filter = NULL, *tmp; + int ret = -EINVAL; + char *s; + + if (!filter_str) /* clear the current filter */ + goto assign; + + s = strsep(&filter_str, " \t"); + + if (!strlen(s) || strcmp(s, "if") != 0) + goto out; + + if (!filter_str) + goto out; + + /* The filter is for the 'trigger' event, not the triggered event */ + ret = create_event_filter(file->event_call, filter_str, false, &filter); + if (ret) + goto out; + assign: + tmp = rcu_access_pointer(data->filter); + + rcu_assign_pointer(data->filter, filter); + + if (tmp) { + /* Make sure the call is done with the filter */ + synchronize_sched(); + free_event_filter(tmp); + } + + kfree(data->filter_str); + data->filter_str = NULL; + + if (filter_str) { + data->filter_str = kstrdup(filter_str, GFP_KERNEL); + if (!data->filter_str) { + free_event_filter(rcu_access_pointer(data->filter)); + data->filter = NULL; + ret = -ENOMEM; + } + } + out: + return ret; +} + +static void +traceon_trigger(struct event_trigger_data *data) +{ + if (tracing_is_on()) + return; + + tracing_on(); +} + +static void +traceon_count_trigger(struct event_trigger_data *data) +{ + if (tracing_is_on()) + return; + + if (!data->count) + return; + + if (data->count != -1) + (data->count)--; + + tracing_on(); +} + +static void +traceoff_trigger(struct event_trigger_data *data) +{ + if (!tracing_is_on()) + return; + + tracing_off(); +} + +static void +traceoff_count_trigger(struct event_trigger_data *data) +{ + if (!tracing_is_on()) + return; + + if (!data->count) + return; + + if (data->count != -1) + (data->count)--; + + tracing_off(); +} + +static int +traceon_trigger_print(struct seq_file *m, struct event_trigger_ops *ops, + struct event_trigger_data *data) +{ + return event_trigger_print("traceon", m, (void *)data->count, + data->filter_str); +} + +static int +traceoff_trigger_print(struct seq_file *m, struct event_trigger_ops *ops, + struct event_trigger_data *data) +{ + return event_trigger_print("traceoff", m, (void *)data->count, + data->filter_str); +} + +static struct event_trigger_ops traceon_trigger_ops = { + .func = traceon_trigger, + .print = traceon_trigger_print, + .init = event_trigger_init, + .free = event_trigger_free, +}; + +static struct event_trigger_ops traceon_count_trigger_ops = { + .func = traceon_count_trigger, + .print = traceon_trigger_print, + .init = event_trigger_init, + .free = event_trigger_free, +}; + +static struct event_trigger_ops traceoff_trigger_ops = { + .func = traceoff_trigger, + .print = traceoff_trigger_print, + .init = event_trigger_init, + .free = event_trigger_free, +}; + +static struct event_trigger_ops traceoff_count_trigger_ops = { + .func = traceoff_count_trigger, + .print = traceoff_trigger_print, + .init = event_trigger_init, + .free = event_trigger_free, +}; + +static struct event_trigger_ops * +onoff_get_trigger_ops(char *cmd, char *param) +{ + struct event_trigger_ops *ops; + + /* we register both traceon and traceoff to this callback */ + if (strcmp(cmd, "traceon") == 0) + ops = param ? &traceon_count_trigger_ops : + &traceon_trigger_ops; + else + ops = param ? &traceoff_count_trigger_ops : + &traceoff_trigger_ops; + + return ops; +} + +static struct event_command trigger_traceon_cmd = { + .name = "traceon", + .trigger_type = ETT_TRACE_ONOFF, + .func = event_trigger_callback, + .reg = register_trigger, + .unreg = unregister_trigger, + .get_trigger_ops = onoff_get_trigger_ops, + .set_filter = set_trigger_filter, +}; + +static struct event_command trigger_traceoff_cmd = { + .name = "traceoff", + .trigger_type = ETT_TRACE_ONOFF, + .func = event_trigger_callback, + .reg = register_trigger, + .unreg = unregister_trigger, + .get_trigger_ops = onoff_get_trigger_ops, + .set_filter = set_trigger_filter, +}; + +#ifdef CONFIG_TRACER_SNAPSHOT +static void +snapshot_trigger(struct event_trigger_data *data) +{ + tracing_snapshot(); +} + +static void +snapshot_count_trigger(struct event_trigger_data *data) +{ + if (!data->count) + return; + + if (data->count != -1) + (data->count)--; + + snapshot_trigger(data); +} + +static int +register_snapshot_trigger(char *glob, struct event_trigger_ops *ops, + struct event_trigger_data *data, + struct ftrace_event_file *file) +{ + int ret = register_trigger(glob, ops, data, file); + + if (ret > 0 && tracing_alloc_snapshot() != 0) { + unregister_trigger(glob, ops, data, file); + ret = 0; + } + + return ret; +} + +static int +snapshot_trigger_print(struct seq_file *m, struct event_trigger_ops *ops, + struct event_trigger_data *data) +{ + return event_trigger_print("snapshot", m, (void *)data->count, + data->filter_str); +} + +static struct event_trigger_ops snapshot_trigger_ops = { + .func = snapshot_trigger, + .print = snapshot_trigger_print, + .init = event_trigger_init, + .free = event_trigger_free, +}; + +static struct event_trigger_ops snapshot_count_trigger_ops = { + .func = snapshot_count_trigger, + .print = snapshot_trigger_print, + .init = event_trigger_init, + .free = event_trigger_free, +}; + +static struct event_trigger_ops * +snapshot_get_trigger_ops(char *cmd, char *param) +{ + return param ? &snapshot_count_trigger_ops : &snapshot_trigger_ops; +} + +static struct event_command trigger_snapshot_cmd = { + .name = "snapshot", + .trigger_type = ETT_SNAPSHOT, + .func = event_trigger_callback, + .reg = register_snapshot_trigger, + .unreg = unregister_trigger, + .get_trigger_ops = snapshot_get_trigger_ops, + .set_filter = set_trigger_filter, +}; + +static __init int register_trigger_snapshot_cmd(void) +{ + int ret; + + ret = register_event_command(&trigger_snapshot_cmd); + WARN_ON(ret < 0); + + return ret; +} +#else +static __init int register_trigger_snapshot_cmd(void) { return 0; } +#endif /* CONFIG_TRACER_SNAPSHOT */ + +#ifdef CONFIG_STACKTRACE +/* + * Skip 3: + * stacktrace_trigger() + * event_triggers_post_call() + * ftrace_raw_event_xxx() + */ +#define STACK_SKIP 3 + +static void +stacktrace_trigger(struct event_trigger_data *data) +{ + trace_dump_stack(STACK_SKIP); +} + +static void +stacktrace_count_trigger(struct event_trigger_data *data) +{ + if (!data->count) + return; + + if (data->count != -1) + (data->count)--; + + stacktrace_trigger(data); +} + +static int +stacktrace_trigger_print(struct seq_file *m, struct event_trigger_ops *ops, + struct event_trigger_data *data) +{ + return event_trigger_print("stacktrace", m, (void *)data->count, + data->filter_str); +} + +static struct event_trigger_ops stacktrace_trigger_ops = { + .func = stacktrace_trigger, + .print = stacktrace_trigger_print, + .init = event_trigger_init, + .free = event_trigger_free, +}; + +static struct event_trigger_ops stacktrace_count_trigger_ops = { + .func = stacktrace_count_trigger, + .print = stacktrace_trigger_print, + .init = event_trigger_init, + .free = event_trigger_free, +}; + +static struct event_trigger_ops * +stacktrace_get_trigger_ops(char *cmd, char *param) +{ + return param ? &stacktrace_count_trigger_ops : &stacktrace_trigger_ops; +} + +static struct event_command trigger_stacktrace_cmd = { + .name = "stacktrace", + .trigger_type = ETT_STACKTRACE, + .post_trigger = true, + .func = event_trigger_callback, + .reg = register_trigger, + .unreg = unregister_trigger, + .get_trigger_ops = stacktrace_get_trigger_ops, + .set_filter = set_trigger_filter, +}; + +static __init int register_trigger_stacktrace_cmd(void) +{ + int ret; + + ret = register_event_command(&trigger_stacktrace_cmd); + WARN_ON(ret < 0); + + return ret; +} +#else +static __init int register_trigger_stacktrace_cmd(void) { return 0; } +#endif /* CONFIG_STACKTRACE */ + +static __init void unregister_trigger_traceon_traceoff_cmds(void) +{ + unregister_event_command(&trigger_traceon_cmd); + unregister_event_command(&trigger_traceoff_cmd); +} + +/* Avoid typos */ +#define ENABLE_EVENT_STR "enable_event" +#define DISABLE_EVENT_STR "disable_event" + +struct enable_trigger_data { + struct ftrace_event_file *file; + bool enable; +}; + +static void +event_enable_trigger(struct event_trigger_data *data) +{ + struct enable_trigger_data *enable_data = data->private_data; + + if (enable_data->enable) + clear_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, &enable_data->file->flags); + else + set_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, &enable_data->file->flags); +} + +static void +event_enable_count_trigger(struct event_trigger_data *data) +{ + struct enable_trigger_data *enable_data = data->private_data; + + if (!data->count) + return; + + /* Skip if the event is in a state we want to switch to */ + if (enable_data->enable == !(enable_data->file->flags & FTRACE_EVENT_FL_SOFT_DISABLED)) + return; + + if (data->count != -1) + (data->count)--; + + event_enable_trigger(data); +} + +static int +event_enable_trigger_print(struct seq_file *m, struct event_trigger_ops *ops, + struct event_trigger_data *data) +{ + struct enable_trigger_data *enable_data = data->private_data; + + seq_printf(m, "%s:%s:%s", + enable_data->enable ? ENABLE_EVENT_STR : DISABLE_EVENT_STR, + enable_data->file->event_call->class->system, + enable_data->file->event_call->name); + + if (data->count == -1) + seq_puts(m, ":unlimited"); + else + seq_printf(m, ":count=%ld", data->count); + + if (data->filter_str) + seq_printf(m, " if %s\n", data->filter_str); + else + seq_puts(m, "\n"); + + return 0; +} + +static void +event_enable_trigger_free(struct event_trigger_ops *ops, + struct event_trigger_data *data) +{ + struct enable_trigger_data *enable_data = data->private_data; + + if (WARN_ON_ONCE(data->ref <= 0)) + return; + + data->ref--; + if (!data->ref) { + /* Remove the SOFT_MODE flag */ + trace_event_enable_disable(enable_data->file, 0, 1); + module_put(enable_data->file->event_call->mod); + trigger_data_free(data); + kfree(enable_data); + } +} + +static struct event_trigger_ops event_enable_trigger_ops = { + .func = event_enable_trigger, + .print = event_enable_trigger_print, + .init = event_trigger_init, + .free = event_enable_trigger_free, +}; + +static struct event_trigger_ops event_enable_count_trigger_ops = { + .func = event_enable_count_trigger, + .print = event_enable_trigger_print, + .init = event_trigger_init, + .free = event_enable_trigger_free, +}; + +static struct event_trigger_ops event_disable_trigger_ops = { + .func = event_enable_trigger, + .print = event_enable_trigger_print, + .init = event_trigger_init, + .free = event_enable_trigger_free, +}; + +static struct event_trigger_ops event_disable_count_trigger_ops = { + .func = event_enable_count_trigger, + .print = event_enable_trigger_print, + .init = event_trigger_init, + .free = event_enable_trigger_free, +}; + +static int +event_enable_trigger_func(struct event_command *cmd_ops, + struct ftrace_event_file *file, + char *glob, char *cmd, char *param) +{ + struct ftrace_event_file *event_enable_file; + struct enable_trigger_data *enable_data; + struct event_trigger_data *trigger_data; + struct event_trigger_ops *trigger_ops; + struct trace_array *tr = file->tr; + const char *system; + const char *event; + char *trigger; + char *number; + bool enable; + int ret; + + if (!param) + return -EINVAL; + + /* separate the trigger from the filter (s:e:n [if filter]) */ + trigger = strsep(¶m, " \t"); + if (!trigger) + return -EINVAL; + + system = strsep(&trigger, ":"); + if (!trigger) + return -EINVAL; + + event = strsep(&trigger, ":"); + + ret = -EINVAL; + event_enable_file = find_event_file(tr, system, event); + if (!event_enable_file) + goto out; + + enable = strcmp(cmd, ENABLE_EVENT_STR) == 0; + + trigger_ops = cmd_ops->get_trigger_ops(cmd, trigger); + + ret = -ENOMEM; + trigger_data = kzalloc(sizeof(*trigger_data), GFP_KERNEL); + if (!trigger_data) + goto out; + + enable_data = kzalloc(sizeof(*enable_data), GFP_KERNEL); + if (!enable_data) { + kfree(trigger_data); + goto out; + } + + trigger_data->count = -1; + trigger_data->ops = trigger_ops; + trigger_data->cmd_ops = cmd_ops; + INIT_LIST_HEAD(&trigger_data->list); + RCU_INIT_POINTER(trigger_data->filter, NULL); + + enable_data->enable = enable; + enable_data->file = event_enable_file; + trigger_data->private_data = enable_data; + + if (glob[0] == '!') { + cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file); + kfree(trigger_data); + kfree(enable_data); + ret = 0; + goto out; + } + + if (trigger) { + number = strsep(&trigger, ":"); + + ret = -EINVAL; + if (!strlen(number)) + goto out_free; + + /* + * We use the callback data field (which is a pointer) + * as our counter. + */ + ret = kstrtoul(number, 0, &trigger_data->count); + if (ret) + goto out_free; + } + + if (!param) /* if param is non-empty, it's supposed to be a filter */ + goto out_reg; + + if (!cmd_ops->set_filter) + goto out_reg; + + ret = cmd_ops->set_filter(param, trigger_data, file); + if (ret < 0) + goto out_free; + + out_reg: + /* Don't let event modules unload while probe registered */ + ret = try_module_get(event_enable_file->event_call->mod); + if (!ret) { + ret = -EBUSY; + goto out_free; + } + + ret = trace_event_enable_disable(event_enable_file, 1, 1); + if (ret < 0) + goto out_put; + ret = cmd_ops->reg(glob, trigger_ops, trigger_data, file); + /* + * The above returns on success the # of functions enabled, + * but if it didn't find any functions it returns zero. + * Consider no functions a failure too. + */ + if (!ret) { + ret = -ENOENT; + goto out_disable; + } else if (ret < 0) + goto out_disable; + /* Just return zero, not the number of enabled functions */ + ret = 0; + out: + return ret; + + out_disable: + trace_event_enable_disable(event_enable_file, 0, 1); + out_put: + module_put(event_enable_file->event_call->mod); + out_free: + if (cmd_ops->set_filter) + cmd_ops->set_filter(NULL, trigger_data, NULL); + kfree(trigger_data); + kfree(enable_data); + goto out; +} + +static int event_enable_register_trigger(char *glob, + struct event_trigger_ops *ops, + struct event_trigger_data *data, + struct ftrace_event_file *file) +{ + struct enable_trigger_data *enable_data = data->private_data; + struct enable_trigger_data *test_enable_data; + struct event_trigger_data *test; + int ret = 0; + + list_for_each_entry_rcu(test, &file->triggers, list) { + test_enable_data = test->private_data; + if (test_enable_data && + (test_enable_data->file == enable_data->file)) { + ret = -EEXIST; + goto out; + } + } + + if (data->ops->init) { + ret = data->ops->init(data->ops, data); + if (ret < 0) + goto out; + } + + list_add_rcu(&data->list, &file->triggers); + ret++; + + if (trace_event_trigger_enable_disable(file, 1) < 0) { + list_del_rcu(&data->list); + ret--; + } + update_cond_flag(file); +out: + return ret; +} + +static void event_enable_unregister_trigger(char *glob, + struct event_trigger_ops *ops, + struct event_trigger_data *test, + struct ftrace_event_file *file) +{ + struct enable_trigger_data *test_enable_data = test->private_data; + struct enable_trigger_data *enable_data; + struct event_trigger_data *data; + bool unregistered = false; + + list_for_each_entry_rcu(data, &file->triggers, list) { + enable_data = data->private_data; + if (enable_data && + (enable_data->file == test_enable_data->file)) { + unregistered = true; + list_del_rcu(&data->list); + update_cond_flag(file); + trace_event_trigger_enable_disable(file, 0); + break; + } + } + + if (unregistered && data->ops->free) + data->ops->free(data->ops, data); +} + +static struct event_trigger_ops * +event_enable_get_trigger_ops(char *cmd, char *param) +{ + struct event_trigger_ops *ops; + bool enable; + + enable = strcmp(cmd, ENABLE_EVENT_STR) == 0; + + if (enable) + ops = param ? &event_enable_count_trigger_ops : + &event_enable_trigger_ops; + else + ops = param ? &event_disable_count_trigger_ops : + &event_disable_trigger_ops; + + return ops; +} + +static struct event_command trigger_enable_cmd = { + .name = ENABLE_EVENT_STR, + .trigger_type = ETT_EVENT_ENABLE, + .func = event_enable_trigger_func, + .reg = event_enable_register_trigger, + .unreg = event_enable_unregister_trigger, + .get_trigger_ops = event_enable_get_trigger_ops, + .set_filter = set_trigger_filter, +}; + +static struct event_command trigger_disable_cmd = { + .name = DISABLE_EVENT_STR, + .trigger_type = ETT_EVENT_ENABLE, + .func = event_enable_trigger_func, + .reg = event_enable_register_trigger, + .unreg = event_enable_unregister_trigger, + .get_trigger_ops = event_enable_get_trigger_ops, + .set_filter = set_trigger_filter, +}; + +static __init void unregister_trigger_enable_disable_cmds(void) +{ + unregister_event_command(&trigger_enable_cmd); + unregister_event_command(&trigger_disable_cmd); +} + +static __init int register_trigger_enable_disable_cmds(void) +{ + int ret; + + ret = register_event_command(&trigger_enable_cmd); + if (WARN_ON(ret < 0)) + return ret; + ret = register_event_command(&trigger_disable_cmd); + if (WARN_ON(ret < 0)) + unregister_trigger_enable_disable_cmds(); + + return ret; +} + +static __init int register_trigger_traceon_traceoff_cmds(void) +{ + int ret; + + ret = register_event_command(&trigger_traceon_cmd); + if (WARN_ON(ret < 0)) + return ret; + ret = register_event_command(&trigger_traceoff_cmd); + if (WARN_ON(ret < 0)) + unregister_trigger_traceon_traceoff_cmds(); + + return ret; +} + +__init int register_trigger_cmds(void) +{ + register_trigger_traceon_traceoff_cmds(); + register_trigger_snapshot_cmd(); + register_trigger_stacktrace_cmd(); + register_trigger_enable_disable_cmds(); + + return 0; +} diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index dae9541..bdbae45 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -27,18 +27,12 @@ /** * Kprobe event core functions */ -struct trace_probe { +struct trace_kprobe { struct list_head list; struct kretprobe rp; /* Use rp.kp for kprobe use */ unsigned long nhit; - unsigned int flags; /* For TP_FLAG_* */ const char *symbol; /* symbol name */ - struct ftrace_event_class class; - struct ftrace_event_call call; - struct list_head files; - ssize_t size; /* trace entry size */ - unsigned int nr_args; - struct probe_arg args[]; + struct trace_probe tp; }; struct event_file_link { @@ -46,56 +40,46 @@ struct event_file_link { struct list_head list; }; -#define SIZEOF_TRACE_PROBE(n) \ - (offsetof(struct trace_probe, args) + \ +#define SIZEOF_TRACE_KPROBE(n) \ + (offsetof(struct trace_kprobe, tp.args) + \ (sizeof(struct probe_arg) * (n))) -static __kprobes bool trace_probe_is_return(struct trace_probe *tp) +static __kprobes bool trace_kprobe_is_return(struct trace_kprobe *tk) { - return tp->rp.handler != NULL; + return tk->rp.handler != NULL; } -static __kprobes const char *trace_probe_symbol(struct trace_probe *tp) +static __kprobes const char *trace_kprobe_symbol(struct trace_kprobe *tk) { - return tp->symbol ? tp->symbol : "unknown"; + return tk->symbol ? tk->symbol : "unknown"; } -static __kprobes unsigned long trace_probe_offset(struct trace_probe *tp) +static __kprobes unsigned long trace_kprobe_offset(struct trace_kprobe *tk) { - return tp->rp.kp.offset; + return tk->rp.kp.offset; } -static __kprobes bool trace_probe_is_enabled(struct trace_probe *tp) +static __kprobes bool trace_kprobe_has_gone(struct trace_kprobe *tk) { - return !!(tp->flags & (TP_FLAG_TRACE | TP_FLAG_PROFILE)); + return !!(kprobe_gone(&tk->rp.kp)); } -static __kprobes bool trace_probe_is_registered(struct trace_probe *tp) -{ - return !!(tp->flags & TP_FLAG_REGISTERED); -} - -static __kprobes bool trace_probe_has_gone(struct trace_probe *tp) -{ - return !!(kprobe_gone(&tp->rp.kp)); -} - -static __kprobes bool trace_probe_within_module(struct trace_probe *tp, - struct module *mod) +static __kprobes bool trace_kprobe_within_module(struct trace_kprobe *tk, + struct module *mod) { int len = strlen(mod->name); - const char *name = trace_probe_symbol(tp); + const char *name = trace_kprobe_symbol(tk); return strncmp(mod->name, name, len) == 0 && name[len] == ':'; } -static __kprobes bool trace_probe_is_on_module(struct trace_probe *tp) +static __kprobes bool trace_kprobe_is_on_module(struct trace_kprobe *tk) { - return !!strchr(trace_probe_symbol(tp), ':'); + return !!strchr(trace_kprobe_symbol(tk), ':'); } -static int register_probe_event(struct trace_probe *tp); -static int unregister_probe_event(struct trace_probe *tp); +static int register_kprobe_event(struct trace_kprobe *tk); +static int unregister_kprobe_event(struct trace_kprobe *tk); static DEFINE_MUTEX(probe_lock); static LIST_HEAD(probe_list); @@ -104,45 +88,224 @@ static int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs); static int kretprobe_dispatcher(struct kretprobe_instance *ri, struct pt_regs *regs); +/* Memory fetching by symbol */ +struct symbol_cache { + char *symbol; + long offset; + unsigned long addr; +}; + +unsigned long update_symbol_cache(struct symbol_cache *sc) +{ + sc->addr = (unsigned long)kallsyms_lookup_name(sc->symbol); + + if (sc->addr) + sc->addr += sc->offset; + + return sc->addr; +} + +void free_symbol_cache(struct symbol_cache *sc) +{ + kfree(sc->symbol); + kfree(sc); +} + +struct symbol_cache *alloc_symbol_cache(const char *sym, long offset) +{ + struct symbol_cache *sc; + + if (!sym || strlen(sym) == 0) + return NULL; + + sc = kzalloc(sizeof(struct symbol_cache), GFP_KERNEL); + if (!sc) + return NULL; + + sc->symbol = kstrdup(sym, GFP_KERNEL); + if (!sc->symbol) { + kfree(sc); + return NULL; + } + sc->offset = offset; + update_symbol_cache(sc); + + return sc; +} + +/* + * Kprobes-specific fetch functions + */ +#define DEFINE_FETCH_stack(type) \ +static __kprobes void FETCH_FUNC_NAME(stack, type)(struct pt_regs *regs,\ + void *offset, void *dest) \ +{ \ + *(type *)dest = (type)regs_get_kernel_stack_nth(regs, \ + (unsigned int)((unsigned long)offset)); \ +} +DEFINE_BASIC_FETCH_FUNCS(stack) +/* No string on the stack entry */ +#define fetch_stack_string NULL +#define fetch_stack_string_size NULL + +#define DEFINE_FETCH_memory(type) \ +static __kprobes void FETCH_FUNC_NAME(memory, type)(struct pt_regs *regs,\ + void *addr, void *dest) \ +{ \ + type retval; \ + if (probe_kernel_address(addr, retval)) \ + *(type *)dest = 0; \ + else \ + *(type *)dest = retval; \ +} +DEFINE_BASIC_FETCH_FUNCS(memory) +/* + * Fetch a null-terminated string. Caller MUST set *(u32 *)dest with max + * length and relative data location. + */ +static __kprobes void FETCH_FUNC_NAME(memory, string)(struct pt_regs *regs, + void *addr, void *dest) +{ + long ret; + int maxlen = get_rloc_len(*(u32 *)dest); + u8 *dst = get_rloc_data(dest); + u8 *src = addr; + mm_segment_t old_fs = get_fs(); + + if (!maxlen) + return; + + /* + * Try to get string again, since the string can be changed while + * probing. + */ + set_fs(KERNEL_DS); + pagefault_disable(); + + do + ret = __copy_from_user_inatomic(dst++, src++, 1); + while (dst[-1] && ret == 0 && src - (u8 *)addr < maxlen); + + dst[-1] = '\0'; + pagefault_enable(); + set_fs(old_fs); + + if (ret < 0) { /* Failed to fetch string */ + ((u8 *)get_rloc_data(dest))[0] = '\0'; + *(u32 *)dest = make_data_rloc(0, get_rloc_offs(*(u32 *)dest)); + } else { + *(u32 *)dest = make_data_rloc(src - (u8 *)addr, + get_rloc_offs(*(u32 *)dest)); + } +} + +/* Return the length of string -- including null terminal byte */ +static __kprobes void FETCH_FUNC_NAME(memory, string_size)(struct pt_regs *regs, + void *addr, void *dest) +{ + mm_segment_t old_fs; + int ret, len = 0; + u8 c; + + old_fs = get_fs(); + set_fs(KERNEL_DS); + pagefault_disable(); + + do { + ret = __copy_from_user_inatomic(&c, (u8 *)addr + len, 1); + len++; + } while (c && ret == 0 && len < MAX_STRING_SIZE); + + pagefault_enable(); + set_fs(old_fs); + + if (ret < 0) /* Failed to check the length */ + *(u32 *)dest = 0; + else + *(u32 *)dest = len; +} + +#define DEFINE_FETCH_symbol(type) \ +__kprobes void FETCH_FUNC_NAME(symbol, type)(struct pt_regs *regs, \ + void *data, void *dest) \ +{ \ + struct symbol_cache *sc = data; \ + if (sc->addr) \ + fetch_memory_##type(regs, (void *)sc->addr, dest); \ + else \ + *(type *)dest = 0; \ +} +DEFINE_BASIC_FETCH_FUNCS(symbol) +DEFINE_FETCH_symbol(string) +DEFINE_FETCH_symbol(string_size) + +/* kprobes don't support file_offset fetch methods */ +#define fetch_file_offset_u8 NULL +#define fetch_file_offset_u16 NULL +#define fetch_file_offset_u32 NULL +#define fetch_file_offset_u64 NULL +#define fetch_file_offset_string NULL +#define fetch_file_offset_string_size NULL + +/* Fetch type information table */ +const struct fetch_type kprobes_fetch_type_table[] = { + /* Special types */ + [FETCH_TYPE_STRING] = __ASSIGN_FETCH_TYPE("string", string, string, + sizeof(u32), 1, "__data_loc char[]"), + [FETCH_TYPE_STRSIZE] = __ASSIGN_FETCH_TYPE("string_size", u32, + string_size, sizeof(u32), 0, "u32"), + /* Basic types */ + ASSIGN_FETCH_TYPE(u8, u8, 0), + ASSIGN_FETCH_TYPE(u16, u16, 0), + ASSIGN_FETCH_TYPE(u32, u32, 0), + ASSIGN_FETCH_TYPE(u64, u64, 0), + ASSIGN_FETCH_TYPE(s8, u8, 1), + ASSIGN_FETCH_TYPE(s16, u16, 1), + ASSIGN_FETCH_TYPE(s32, u32, 1), + ASSIGN_FETCH_TYPE(s64, u64, 1), + + ASSIGN_FETCH_TYPE_END +}; + /* * Allocate new trace_probe and initialize it (including kprobes). */ -static struct trace_probe *alloc_trace_probe(const char *group, +static struct trace_kprobe *alloc_trace_kprobe(const char *group, const char *event, void *addr, const char *symbol, unsigned long offs, int nargs, bool is_return) { - struct trace_probe *tp; + struct trace_kprobe *tk; int ret = -ENOMEM; - tp = kzalloc(SIZEOF_TRACE_PROBE(nargs), GFP_KERNEL); - if (!tp) + tk = kzalloc(SIZEOF_TRACE_KPROBE(nargs), GFP_KERNEL); + if (!tk) return ERR_PTR(ret); if (symbol) { - tp->symbol = kstrdup(symbol, GFP_KERNEL); - if (!tp->symbol) + tk->symbol = kstrdup(symbol, GFP_KERNEL); + if (!tk->symbol) goto error; - tp->rp.kp.symbol_name = tp->symbol; - tp->rp.kp.offset = offs; + tk->rp.kp.symbol_name = tk->symbol; + tk->rp.kp.offset = offs; } else - tp->rp.kp.addr = addr; + tk->rp.kp.addr = addr; if (is_return) - tp->rp.handler = kretprobe_dispatcher; + tk->rp.handler = kretprobe_dispatcher; else - tp->rp.kp.pre_handler = kprobe_dispatcher; + tk->rp.kp.pre_handler = kprobe_dispatcher; if (!event || !is_good_name(event)) { ret = -EINVAL; goto error; } - tp->call.class = &tp->class; - tp->call.name = kstrdup(event, GFP_KERNEL); - if (!tp->call.name) + tk->tp.call.class = &tk->tp.class; + tk->tp.call.name = kstrdup(event, GFP_KERNEL); + if (!tk->tp.call.name) goto error; if (!group || !is_good_name(group)) { @@ -150,42 +313,42 @@ static struct trace_probe *alloc_trace_probe(const char *group, goto error; } - tp->class.system = kstrdup(group, GFP_KERNEL); - if (!tp->class.system) + tk->tp.class.system = kstrdup(group, GFP_KERNEL); + if (!tk->tp.class.system) goto error; - INIT_LIST_HEAD(&tp->list); - INIT_LIST_HEAD(&tp->files); - return tp; + INIT_LIST_HEAD(&tk->list); + INIT_LIST_HEAD(&tk->tp.files); + return tk; error: - kfree(tp->call.name); - kfree(tp->symbol); - kfree(tp); + kfree(tk->tp.call.name); + kfree(tk->symbol); + kfree(tk); return ERR_PTR(ret); } -static void free_trace_probe(struct trace_probe *tp) +static void free_trace_kprobe(struct trace_kprobe *tk) { int i; - for (i = 0; i < tp->nr_args; i++) - traceprobe_free_probe_arg(&tp->args[i]); + for (i = 0; i < tk->tp.nr_args; i++) + traceprobe_free_probe_arg(&tk->tp.args[i]); - kfree(tp->call.class->system); - kfree(tp->call.name); - kfree(tp->symbol); - kfree(tp); + kfree(tk->tp.call.class->system); + kfree(tk->tp.call.name); + kfree(tk->symbol); + kfree(tk); } -static struct trace_probe *find_trace_probe(const char *event, - const char *group) +static struct trace_kprobe *find_trace_kprobe(const char *event, + const char *group) { - struct trace_probe *tp; + struct trace_kprobe *tk; - list_for_each_entry(tp, &probe_list, list) - if (strcmp(tp->call.name, event) == 0 && - strcmp(tp->call.class->system, group) == 0) - return tp; + list_for_each_entry(tk, &probe_list, list) + if (strcmp(tk->tp.call.name, event) == 0 && + strcmp(tk->tp.call.class->system, group) == 0) + return tk; return NULL; } @@ -194,7 +357,7 @@ static struct trace_probe *find_trace_probe(const char *event, * if the file is NULL, enable "perf" handler, or enable "trace" handler. */ static int -enable_trace_probe(struct trace_probe *tp, struct ftrace_event_file *file) +enable_trace_kprobe(struct trace_kprobe *tk, struct ftrace_event_file *file) { int ret = 0; @@ -208,17 +371,17 @@ enable_trace_probe(struct trace_probe *tp, struct ftrace_event_file *file) } link->file = file; - list_add_tail_rcu(&link->list, &tp->files); + list_add_tail_rcu(&link->list, &tk->tp.files); - tp->flags |= TP_FLAG_TRACE; + tk->tp.flags |= TP_FLAG_TRACE; } else - tp->flags |= TP_FLAG_PROFILE; + tk->tp.flags |= TP_FLAG_PROFILE; - if (trace_probe_is_registered(tp) && !trace_probe_has_gone(tp)) { - if (trace_probe_is_return(tp)) - ret = enable_kretprobe(&tp->rp); + if (trace_probe_is_registered(&tk->tp) && !trace_kprobe_has_gone(tk)) { + if (trace_kprobe_is_return(tk)) + ret = enable_kretprobe(&tk->rp); else - ret = enable_kprobe(&tp->rp.kp); + ret = enable_kprobe(&tk->rp.kp); } out: return ret; @@ -241,14 +404,14 @@ find_event_file_link(struct trace_probe *tp, struct ftrace_event_file *file) * if the file is NULL, disable "perf" handler, or disable "trace" handler. */ static int -disable_trace_probe(struct trace_probe *tp, struct ftrace_event_file *file) +disable_trace_kprobe(struct trace_kprobe *tk, struct ftrace_event_file *file) { struct event_file_link *link = NULL; int wait = 0; int ret = 0; if (file) { - link = find_event_file_link(tp, file); + link = find_event_file_link(&tk->tp, file); if (!link) { ret = -EINVAL; goto out; @@ -256,18 +419,18 @@ disable_trace_probe(struct trace_probe *tp, struct ftrace_event_file *file) list_del_rcu(&link->list); wait = 1; - if (!list_empty(&tp->files)) + if (!list_empty(&tk->tp.files)) goto out; - tp->flags &= ~TP_FLAG_TRACE; + tk->tp.flags &= ~TP_FLAG_TRACE; } else - tp->flags &= ~TP_FLAG_PROFILE; + tk->tp.flags &= ~TP_FLAG_PROFILE; - if (!trace_probe_is_enabled(tp) && trace_probe_is_registered(tp)) { - if (trace_probe_is_return(tp)) - disable_kretprobe(&tp->rp); + if (!trace_probe_is_enabled(&tk->tp) && trace_probe_is_registered(&tk->tp)) { + if (trace_kprobe_is_return(tk)) + disable_kretprobe(&tk->rp); else - disable_kprobe(&tp->rp.kp); + disable_kprobe(&tk->rp.kp); wait = 1; } out: @@ -288,40 +451,40 @@ disable_trace_probe(struct trace_probe *tp, struct ftrace_event_file *file) } /* Internal register function - just handle k*probes and flags */ -static int __register_trace_probe(struct trace_probe *tp) +static int __register_trace_kprobe(struct trace_kprobe *tk) { int i, ret; - if (trace_probe_is_registered(tp)) + if (trace_probe_is_registered(&tk->tp)) return -EINVAL; - for (i = 0; i < tp->nr_args; i++) - traceprobe_update_arg(&tp->args[i]); + for (i = 0; i < tk->tp.nr_args; i++) + traceprobe_update_arg(&tk->tp.args[i]); /* Set/clear disabled flag according to tp->flag */ - if (trace_probe_is_enabled(tp)) - tp->rp.kp.flags &= ~KPROBE_FLAG_DISABLED; + if (trace_probe_is_enabled(&tk->tp)) + tk->rp.kp.flags &= ~KPROBE_FLAG_DISABLED; else - tp->rp.kp.flags |= KPROBE_FLAG_DISABLED; + tk->rp.kp.flags |= KPROBE_FLAG_DISABLED; - if (trace_probe_is_return(tp)) - ret = register_kretprobe(&tp->rp); + if (trace_kprobe_is_return(tk)) + ret = register_kretprobe(&tk->rp); else - ret = register_kprobe(&tp->rp.kp); + ret = register_kprobe(&tk->rp.kp); if (ret == 0) - tp->flags |= TP_FLAG_REGISTERED; + tk->tp.flags |= TP_FLAG_REGISTERED; else { pr_warning("Could not insert probe at %s+%lu: %d\n", - trace_probe_symbol(tp), trace_probe_offset(tp), ret); - if (ret == -ENOENT && trace_probe_is_on_module(tp)) { + trace_kprobe_symbol(tk), trace_kprobe_offset(tk), ret); + if (ret == -ENOENT && trace_kprobe_is_on_module(tk)) { pr_warning("This probe might be able to register after" "target module is loaded. Continue.\n"); ret = 0; } else if (ret == -EILSEQ) { pr_warning("Probing address(0x%p) is not an " "instruction boundary.\n", - tp->rp.kp.addr); + tk->rp.kp.addr); ret = -EINVAL; } } @@ -330,67 +493,67 @@ static int __register_trace_probe(struct trace_probe *tp) } /* Internal unregister function - just handle k*probes and flags */ -static void __unregister_trace_probe(struct trace_probe *tp) +static void __unregister_trace_kprobe(struct trace_kprobe *tk) { - if (trace_probe_is_registered(tp)) { - if (trace_probe_is_return(tp)) - unregister_kretprobe(&tp->rp); + if (trace_probe_is_registered(&tk->tp)) { + if (trace_kprobe_is_return(tk)) + unregister_kretprobe(&tk->rp); else - unregister_kprobe(&tp->rp.kp); - tp->flags &= ~TP_FLAG_REGISTERED; + unregister_kprobe(&tk->rp.kp); + tk->tp.flags &= ~TP_FLAG_REGISTERED; /* Cleanup kprobe for reuse */ - if (tp->rp.kp.symbol_name) - tp->rp.kp.addr = NULL; + if (tk->rp.kp.symbol_name) + tk->rp.kp.addr = NULL; } } /* Unregister a trace_probe and probe_event: call with locking probe_lock */ -static int unregister_trace_probe(struct trace_probe *tp) +static int unregister_trace_kprobe(struct trace_kprobe *tk) { /* Enabled event can not be unregistered */ - if (trace_probe_is_enabled(tp)) + if (trace_probe_is_enabled(&tk->tp)) return -EBUSY; /* Will fail if probe is being used by ftrace or perf */ - if (unregister_probe_event(tp)) + if (unregister_kprobe_event(tk)) return -EBUSY; - __unregister_trace_probe(tp); - list_del(&tp->list); + __unregister_trace_kprobe(tk); + list_del(&tk->list); return 0; } /* Register a trace_probe and probe_event */ -static int register_trace_probe(struct trace_probe *tp) +static int register_trace_kprobe(struct trace_kprobe *tk) { - struct trace_probe *old_tp; + struct trace_kprobe *old_tk; int ret; mutex_lock(&probe_lock); /* Delete old (same name) event if exist */ - old_tp = find_trace_probe(tp->call.name, tp->call.class->system); - if (old_tp) { - ret = unregister_trace_probe(old_tp); + old_tk = find_trace_kprobe(tk->tp.call.name, tk->tp.call.class->system); + if (old_tk) { + ret = unregister_trace_kprobe(old_tk); if (ret < 0) goto end; - free_trace_probe(old_tp); + free_trace_kprobe(old_tk); } /* Register new event */ - ret = register_probe_event(tp); + ret = register_kprobe_event(tk); if (ret) { pr_warning("Failed to register probe event(%d)\n", ret); goto end; } /* Register k*probe */ - ret = __register_trace_probe(tp); + ret = __register_trace_kprobe(tk); if (ret < 0) - unregister_probe_event(tp); + unregister_kprobe_event(tk); else - list_add_tail(&tp->list, &probe_list); + list_add_tail(&tk->list, &probe_list); end: mutex_unlock(&probe_lock); @@ -398,11 +561,11 @@ end: } /* Module notifier call back, checking event on the module */ -static int trace_probe_module_callback(struct notifier_block *nb, +static int trace_kprobe_module_callback(struct notifier_block *nb, unsigned long val, void *data) { struct module *mod = data; - struct trace_probe *tp; + struct trace_kprobe *tk; int ret; if (val != MODULE_STATE_COMING) @@ -410,15 +573,15 @@ static int trace_probe_module_callback(struct notifier_block *nb, /* Update probes on coming module */ mutex_lock(&probe_lock); - list_for_each_entry(tp, &probe_list, list) { - if (trace_probe_within_module(tp, mod)) { + list_for_each_entry(tk, &probe_list, list) { + if (trace_kprobe_within_module(tk, mod)) { /* Don't need to check busy - this should have gone. */ - __unregister_trace_probe(tp); - ret = __register_trace_probe(tp); + __unregister_trace_kprobe(tk); + ret = __register_trace_kprobe(tk); if (ret) pr_warning("Failed to re-register probe %s on" "%s: %d\n", - tp->call.name, mod->name, ret); + tk->tp.call.name, mod->name, ret); } } mutex_unlock(&probe_lock); @@ -426,12 +589,12 @@ static int trace_probe_module_callback(struct notifier_block *nb, return NOTIFY_DONE; } -static struct notifier_block trace_probe_module_nb = { - .notifier_call = trace_probe_module_callback, +static struct notifier_block trace_kprobe_module_nb = { + .notifier_call = trace_kprobe_module_callback, .priority = 1 /* Invoked after kprobe module callback */ }; -static int create_trace_probe(int argc, char **argv) +static int create_trace_kprobe(int argc, char **argv) { /* * Argument syntax: @@ -451,7 +614,7 @@ static int create_trace_probe(int argc, char **argv) * Type of args: * FETCHARG:TYPE : use TYPE instead of unsigned long. */ - struct trace_probe *tp; + struct trace_kprobe *tk; int i, ret = 0; bool is_return = false, is_delete = false; char *symbol = NULL, *event = NULL, *group = NULL; @@ -498,16 +661,16 @@ static int create_trace_probe(int argc, char **argv) return -EINVAL; } mutex_lock(&probe_lock); - tp = find_trace_probe(event, group); - if (!tp) { + tk = find_trace_kprobe(event, group); + if (!tk) { mutex_unlock(&probe_lock); pr_info("Event %s/%s doesn't exist.\n", group, event); return -ENOENT; } /* delete an event */ - ret = unregister_trace_probe(tp); + ret = unregister_trace_kprobe(tk); if (ret == 0) - free_trace_probe(tp); + free_trace_kprobe(tk); mutex_unlock(&probe_lock); return ret; } @@ -554,47 +717,49 @@ static int create_trace_probe(int argc, char **argv) is_return ? 'r' : 'p', addr); event = buf; } - tp = alloc_trace_probe(group, event, addr, symbol, offset, argc, + tk = alloc_trace_kprobe(group, event, addr, symbol, offset, argc, is_return); - if (IS_ERR(tp)) { + if (IS_ERR(tk)) { pr_info("Failed to allocate trace_probe.(%d)\n", - (int)PTR_ERR(tp)); - return PTR_ERR(tp); + (int)PTR_ERR(tk)); + return PTR_ERR(tk); } /* parse arguments */ ret = 0; for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) { + struct probe_arg *parg = &tk->tp.args[i]; + /* Increment count for freeing args in error case */ - tp->nr_args++; + tk->tp.nr_args++; /* Parse argument name */ arg = strchr(argv[i], '='); if (arg) { *arg++ = '\0'; - tp->args[i].name = kstrdup(argv[i], GFP_KERNEL); + parg->name = kstrdup(argv[i], GFP_KERNEL); } else { arg = argv[i]; /* If argument name is omitted, set "argN" */ snprintf(buf, MAX_EVENT_NAME_LEN, "arg%d", i + 1); - tp->args[i].name = kstrdup(buf, GFP_KERNEL); + parg->name = kstrdup(buf, GFP_KERNEL); } - if (!tp->args[i].name) { + if (!parg->name) { pr_info("Failed to allocate argument[%d] name.\n", i); ret = -ENOMEM; goto error; } - if (!is_good_name(tp->args[i].name)) { + if (!is_good_name(parg->name)) { pr_info("Invalid argument[%d] name: %s\n", - i, tp->args[i].name); + i, parg->name); ret = -EINVAL; goto error; } - if (traceprobe_conflict_field_name(tp->args[i].name, - tp->args, i)) { + if (traceprobe_conflict_field_name(parg->name, + tk->tp.args, i)) { pr_info("Argument[%d] name '%s' conflicts with " "another field.\n", i, argv[i]); ret = -EINVAL; @@ -602,7 +767,7 @@ static int create_trace_probe(int argc, char **argv) } /* Parse fetch argument */ - ret = traceprobe_parse_probe_arg(arg, &tp->size, &tp->args[i], + ret = traceprobe_parse_probe_arg(arg, &tk->tp.size, parg, is_return, true); if (ret) { pr_info("Parse error at argument[%d]. (%d)\n", i, ret); @@ -610,35 +775,35 @@ static int create_trace_probe(int argc, char **argv) } } - ret = register_trace_probe(tp); + ret = register_trace_kprobe(tk); if (ret) goto error; return 0; error: - free_trace_probe(tp); + free_trace_kprobe(tk); return ret; } -static int release_all_trace_probes(void) +static int release_all_trace_kprobes(void) { - struct trace_probe *tp; + struct trace_kprobe *tk; int ret = 0; mutex_lock(&probe_lock); /* Ensure no probe is in use. */ - list_for_each_entry(tp, &probe_list, list) - if (trace_probe_is_enabled(tp)) { + list_for_each_entry(tk, &probe_list, list) + if (trace_probe_is_enabled(&tk->tp)) { ret = -EBUSY; goto end; } /* TODO: Use batch unregistration */ while (!list_empty(&probe_list)) { - tp = list_entry(probe_list.next, struct trace_probe, list); - ret = unregister_trace_probe(tp); + tk = list_entry(probe_list.next, struct trace_kprobe, list); + ret = unregister_trace_kprobe(tk); if (ret) goto end; - free_trace_probe(tp); + free_trace_kprobe(tk); } end: @@ -666,22 +831,22 @@ static void probes_seq_stop(struct seq_file *m, void *v) static int probes_seq_show(struct seq_file *m, void *v) { - struct trace_probe *tp = v; + struct trace_kprobe *tk = v; int i; - seq_printf(m, "%c", trace_probe_is_return(tp) ? 'r' : 'p'); - seq_printf(m, ":%s/%s", tp->call.class->system, tp->call.name); + seq_printf(m, "%c", trace_kprobe_is_return(tk) ? 'r' : 'p'); + seq_printf(m, ":%s/%s", tk->tp.call.class->system, tk->tp.call.name); - if (!tp->symbol) - seq_printf(m, " 0x%p", tp->rp.kp.addr); - else if (tp->rp.kp.offset) - seq_printf(m, " %s+%u", trace_probe_symbol(tp), - tp->rp.kp.offset); + if (!tk->symbol) + seq_printf(m, " 0x%p", tk->rp.kp.addr); + else if (tk->rp.kp.offset) + seq_printf(m, " %s+%u", trace_kprobe_symbol(tk), + tk->rp.kp.offset); else - seq_printf(m, " %s", trace_probe_symbol(tp)); + seq_printf(m, " %s", trace_kprobe_symbol(tk)); - for (i = 0; i < tp->nr_args; i++) - seq_printf(m, " %s=%s", tp->args[i].name, tp->args[i].comm); + for (i = 0; i < tk->tp.nr_args; i++) + seq_printf(m, " %s=%s", tk->tp.args[i].name, tk->tp.args[i].comm); seq_printf(m, "\n"); return 0; @@ -699,7 +864,7 @@ static int probes_open(struct inode *inode, struct file *file) int ret; if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) { - ret = release_all_trace_probes(); + ret = release_all_trace_kprobes(); if (ret < 0) return ret; } @@ -711,7 +876,7 @@ static ssize_t probes_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos) { return traceprobe_probes_write(file, buffer, count, ppos, - create_trace_probe); + create_trace_kprobe); } static const struct file_operations kprobe_events_ops = { @@ -726,10 +891,10 @@ static const struct file_operations kprobe_events_ops = { /* Probes profiling interfaces */ static int probes_profile_seq_show(struct seq_file *m, void *v) { - struct trace_probe *tp = v; + struct trace_kprobe *tk = v; - seq_printf(m, " %-44s %15lu %15lu\n", tp->call.name, tp->nhit, - tp->rp.kp.nmissed); + seq_printf(m, " %-44s %15lu %15lu\n", tk->tp.call.name, tk->nhit, + tk->rp.kp.nmissed); return 0; } @@ -754,57 +919,9 @@ static const struct file_operations kprobe_profile_ops = { .release = seq_release, }; -/* Sum up total data length for dynamic arraies (strings) */ -static __kprobes int __get_data_size(struct trace_probe *tp, - struct pt_regs *regs) -{ - int i, ret = 0; - u32 len; - - for (i = 0; i < tp->nr_args; i++) - if (unlikely(tp->args[i].fetch_size.fn)) { - call_fetch(&tp->args[i].fetch_size, regs, &len); - ret += len; - } - - return ret; -} - -/* Store the value of each argument */ -static __kprobes void store_trace_args(int ent_size, struct trace_probe *tp, - struct pt_regs *regs, - u8 *data, int maxlen) -{ - int i; - u32 end = tp->size; - u32 *dl; /* Data (relative) location */ - - for (i = 0; i < tp->nr_args; i++) { - if (unlikely(tp->args[i].fetch_size.fn)) { - /* - * First, we set the relative location and - * maximum data length to *dl - */ - dl = (u32 *)(data + tp->args[i].offset); - *dl = make_data_rloc(maxlen, end - tp->args[i].offset); - /* Then try to fetch string or dynamic array data */ - call_fetch(&tp->args[i].fetch, regs, dl); - /* Reduce maximum length */ - end += get_rloc_len(*dl); - maxlen -= get_rloc_len(*dl); - /* Trick here, convert data_rloc to data_loc */ - *dl = convert_rloc_to_loc(*dl, - ent_size + tp->args[i].offset); - } else - /* Just fetching data normally */ - call_fetch(&tp->args[i].fetch, regs, - data + tp->args[i].offset); - } -} - /* Kprobe handler */ static __kprobes void -__kprobe_trace_func(struct trace_probe *tp, struct pt_regs *regs, +__kprobe_trace_func(struct trace_kprobe *tk, struct pt_regs *regs, struct ftrace_event_file *ftrace_file) { struct kprobe_trace_entry_head *entry; @@ -812,18 +929,18 @@ __kprobe_trace_func(struct trace_probe *tp, struct pt_regs *regs, struct ring_buffer *buffer; int size, dsize, pc; unsigned long irq_flags; - struct ftrace_event_call *call = &tp->call; + struct ftrace_event_call *call = &tk->tp.call; WARN_ON(call != ftrace_file->event_call); - if (test_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, &ftrace_file->flags)) + if (ftrace_trigger_soft_disabled(ftrace_file)) return; local_save_flags(irq_flags); pc = preempt_count(); - dsize = __get_data_size(tp, regs); - size = sizeof(*entry) + tp->size + dsize; + dsize = __get_data_size(&tk->tp, regs); + size = sizeof(*entry) + tk->tp.size + dsize; event = trace_event_buffer_lock_reserve(&buffer, ftrace_file, call->event.type, @@ -832,26 +949,25 @@ __kprobe_trace_func(struct trace_probe *tp, struct pt_regs *regs, return; entry = ring_buffer_event_data(event); - entry->ip = (unsigned long)tp->rp.kp.addr; - store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize); + entry->ip = (unsigned long)tk->rp.kp.addr; + store_trace_args(sizeof(*entry), &tk->tp, regs, (u8 *)&entry[1], dsize); - if (!filter_check_discard(ftrace_file, entry, buffer, event)) - trace_buffer_unlock_commit_regs(buffer, event, - irq_flags, pc, regs); + event_trigger_unlock_commit_regs(ftrace_file, buffer, event, + entry, irq_flags, pc, regs); } static __kprobes void -kprobe_trace_func(struct trace_probe *tp, struct pt_regs *regs) +kprobe_trace_func(struct trace_kprobe *tk, struct pt_regs *regs) { struct event_file_link *link; - list_for_each_entry_rcu(link, &tp->files, list) - __kprobe_trace_func(tp, regs, link->file); + list_for_each_entry_rcu(link, &tk->tp.files, list) + __kprobe_trace_func(tk, regs, link->file); } /* Kretprobe handler */ static __kprobes void -__kretprobe_trace_func(struct trace_probe *tp, struct kretprobe_instance *ri, +__kretprobe_trace_func(struct trace_kprobe *tk, struct kretprobe_instance *ri, struct pt_regs *regs, struct ftrace_event_file *ftrace_file) { @@ -860,18 +976,18 @@ __kretprobe_trace_func(struct trace_probe *tp, struct kretprobe_instance *ri, struct ring_buffer *buffer; int size, pc, dsize; unsigned long irq_flags; - struct ftrace_event_call *call = &tp->call; + struct ftrace_event_call *call = &tk->tp.call; WARN_ON(call != ftrace_file->event_call); - if (test_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, &ftrace_file->flags)) + if (ftrace_trigger_soft_disabled(ftrace_file)) return; local_save_flags(irq_flags); pc = preempt_count(); - dsize = __get_data_size(tp, regs); - size = sizeof(*entry) + tp->size + dsize; + dsize = __get_data_size(&tk->tp, regs); + size = sizeof(*entry) + tk->tp.size + dsize; event = trace_event_buffer_lock_reserve(&buffer, ftrace_file, call->event.type, @@ -880,23 +996,22 @@ __kretprobe_trace_func(struct trace_probe *tp, struct kretprobe_instance *ri, return; entry = ring_buffer_event_data(event); - entry->func = (unsigned long)tp->rp.kp.addr; + entry->func = (unsigned long)tk->rp.kp.addr; entry->ret_ip = (unsigned long)ri->ret_addr; - store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize); + store_trace_args(sizeof(*entry), &tk->tp, regs, (u8 *)&entry[1], dsize); - if (!filter_check_discard(ftrace_file, entry, buffer, event)) - trace_buffer_unlock_commit_regs(buffer, event, - irq_flags, pc, regs); + event_trigger_unlock_commit_regs(ftrace_file, buffer, event, + entry, irq_flags, pc, regs); } static __kprobes void -kretprobe_trace_func(struct trace_probe *tp, struct kretprobe_instance *ri, +kretprobe_trace_func(struct trace_kprobe *tk, struct kretprobe_instance *ri, struct pt_regs *regs) { struct event_file_link *link; - list_for_each_entry_rcu(link, &tp->files, list) - __kretprobe_trace_func(tp, ri, regs, link->file); + list_for_each_entry_rcu(link, &tk->tp.files, list) + __kretprobe_trace_func(tk, ri, regs, link->file); } /* Event entry printers */ @@ -983,16 +1098,18 @@ static int kprobe_event_define_fields(struct ftrace_event_call *event_call) { int ret, i; struct kprobe_trace_entry_head field; - struct trace_probe *tp = (struct trace_probe *)event_call->data; + struct trace_kprobe *tk = (struct trace_kprobe *)event_call->data; DEFINE_FIELD(unsigned long, ip, FIELD_STRING_IP, 0); /* Set argument names as fields */ - for (i = 0; i < tp->nr_args; i++) { - ret = trace_define_field(event_call, tp->args[i].type->fmttype, - tp->args[i].name, - sizeof(field) + tp->args[i].offset, - tp->args[i].type->size, - tp->args[i].type->is_signed, + for (i = 0; i < tk->tp.nr_args; i++) { + struct probe_arg *parg = &tk->tp.args[i]; + + ret = trace_define_field(event_call, parg->type->fmttype, + parg->name, + sizeof(field) + parg->offset, + parg->type->size, + parg->type->is_signed, FILTER_OTHER); if (ret) return ret; @@ -1004,17 +1121,19 @@ static int kretprobe_event_define_fields(struct ftrace_event_call *event_call) { int ret, i; struct kretprobe_trace_entry_head field; - struct trace_probe *tp = (struct trace_probe *)event_call->data; + struct trace_kprobe *tk = (struct trace_kprobe *)event_call->data; DEFINE_FIELD(unsigned long, func, FIELD_STRING_FUNC, 0); DEFINE_FIELD(unsigned long, ret_ip, FIELD_STRING_RETIP, 0); /* Set argument names as fields */ - for (i = 0; i < tp->nr_args; i++) { - ret = trace_define_field(event_call, tp->args[i].type->fmttype, - tp->args[i].name, - sizeof(field) + tp->args[i].offset, - tp->args[i].type->size, - tp->args[i].type->is_signed, + for (i = 0; i < tk->tp.nr_args; i++) { + struct probe_arg *parg = &tk->tp.args[i]; + + ret = trace_define_field(event_call, parg->type->fmttype, + parg->name, + sizeof(field) + parg->offset, + parg->type->size, + parg->type->is_signed, FILTER_OTHER); if (ret) return ret; @@ -1022,74 +1141,13 @@ static int kretprobe_event_define_fields(struct ftrace_event_call *event_call) return 0; } -static int __set_print_fmt(struct trace_probe *tp, char *buf, int len) -{ - int i; - int pos = 0; - - const char *fmt, *arg; - - if (!trace_probe_is_return(tp)) { - fmt = "(%lx)"; - arg = "REC->" FIELD_STRING_IP; - } else { - fmt = "(%lx <- %lx)"; - arg = "REC->" FIELD_STRING_FUNC ", REC->" FIELD_STRING_RETIP; - } - - /* When len=0, we just calculate the needed length */ -#define LEN_OR_ZERO (len ? len - pos : 0) - - pos += snprintf(buf + pos, LEN_OR_ZERO, "\"%s", fmt); - - for (i = 0; i < tp->nr_args; i++) { - pos += snprintf(buf + pos, LEN_OR_ZERO, " %s=%s", - tp->args[i].name, tp->args[i].type->fmt); - } - - pos += snprintf(buf + pos, LEN_OR_ZERO, "\", %s", arg); - - for (i = 0; i < tp->nr_args; i++) { - if (strcmp(tp->args[i].type->name, "string") == 0) - pos += snprintf(buf + pos, LEN_OR_ZERO, - ", __get_str(%s)", - tp->args[i].name); - else - pos += snprintf(buf + pos, LEN_OR_ZERO, ", REC->%s", - tp->args[i].name); - } - -#undef LEN_OR_ZERO - - /* return the length of print_fmt */ - return pos; -} - -static int set_print_fmt(struct trace_probe *tp) -{ - int len; - char *print_fmt; - - /* First: called with 0 length to calculate the needed length */ - len = __set_print_fmt(tp, NULL, 0); - print_fmt = kmalloc(len + 1, GFP_KERNEL); - if (!print_fmt) - return -ENOMEM; - - /* Second: actually write the @print_fmt */ - __set_print_fmt(tp, print_fmt, len + 1); - tp->call.print_fmt = print_fmt; - - return 0; -} - #ifdef CONFIG_PERF_EVENTS /* Kprobe profile handler */ static __kprobes void -kprobe_perf_func(struct trace_probe *tp, struct pt_regs *regs) +kprobe_perf_func(struct trace_kprobe *tk, struct pt_regs *regs) { - struct ftrace_event_call *call = &tp->call; + struct ftrace_event_call *call = &tk->tp.call; struct kprobe_trace_entry_head *entry; struct hlist_head *head; int size, __size, dsize; @@ -1099,8 +1157,8 @@ kprobe_perf_func(struct trace_probe *tp, struct pt_regs *regs) if (hlist_empty(head)) return; - dsize = __get_data_size(tp, regs); - __size = sizeof(*entry) + tp->size + dsize; + dsize = __get_data_size(&tk->tp, regs); + __size = sizeof(*entry) + tk->tp.size + dsize; size = ALIGN(__size + sizeof(u32), sizeof(u64)); size -= sizeof(u32); @@ -1108,18 +1166,18 @@ kprobe_perf_func(struct trace_probe *tp, struct pt_regs *regs) if (!entry) return; - entry->ip = (unsigned long)tp->rp.kp.addr; + entry->ip = (unsigned long)tk->rp.kp.addr; memset(&entry[1], 0, dsize); - store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize); + store_trace_args(sizeof(*entry), &tk->tp, regs, (u8 *)&entry[1], dsize); perf_trace_buf_submit(entry, size, rctx, 0, 1, regs, head, NULL); } /* Kretprobe profile handler */ static __kprobes void -kretprobe_perf_func(struct trace_probe *tp, struct kretprobe_instance *ri, +kretprobe_perf_func(struct trace_kprobe *tk, struct kretprobe_instance *ri, struct pt_regs *regs) { - struct ftrace_event_call *call = &tp->call; + struct ftrace_event_call *call = &tk->tp.call; struct kretprobe_trace_entry_head *entry; struct hlist_head *head; int size, __size, dsize; @@ -1129,8 +1187,8 @@ kretprobe_perf_func(struct trace_probe *tp, struct kretprobe_instance *ri, if (hlist_empty(head)) return; - dsize = __get_data_size(tp, regs); - __size = sizeof(*entry) + tp->size + dsize; + dsize = __get_data_size(&tk->tp, regs); + __size = sizeof(*entry) + tk->tp.size + dsize; size = ALIGN(__size + sizeof(u32), sizeof(u64)); size -= sizeof(u32); @@ -1138,9 +1196,9 @@ kretprobe_perf_func(struct trace_probe *tp, struct kretprobe_instance *ri, if (!entry) return; - entry->func = (unsigned long)tp->rp.kp.addr; + entry->func = (unsigned long)tk->rp.kp.addr; entry->ret_ip = (unsigned long)ri->ret_addr; - store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize); + store_trace_args(sizeof(*entry), &tk->tp, regs, (u8 *)&entry[1], dsize); perf_trace_buf_submit(entry, size, rctx, 0, 1, regs, head, NULL); } #endif /* CONFIG_PERF_EVENTS */ @@ -1155,20 +1213,20 @@ static __kprobes int kprobe_register(struct ftrace_event_call *event, enum trace_reg type, void *data) { - struct trace_probe *tp = (struct trace_probe *)event->data; + struct trace_kprobe *tk = (struct trace_kprobe *)event->data; struct ftrace_event_file *file = data; switch (type) { case TRACE_REG_REGISTER: - return enable_trace_probe(tp, file); + return enable_trace_kprobe(tk, file); case TRACE_REG_UNREGISTER: - return disable_trace_probe(tp, file); + return disable_trace_kprobe(tk, file); #ifdef CONFIG_PERF_EVENTS case TRACE_REG_PERF_REGISTER: - return enable_trace_probe(tp, NULL); + return enable_trace_kprobe(tk, NULL); case TRACE_REG_PERF_UNREGISTER: - return disable_trace_probe(tp, NULL); + return disable_trace_kprobe(tk, NULL); case TRACE_REG_PERF_OPEN: case TRACE_REG_PERF_CLOSE: case TRACE_REG_PERF_ADD: @@ -1182,15 +1240,15 @@ int kprobe_register(struct ftrace_event_call *event, static __kprobes int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs) { - struct trace_probe *tp = container_of(kp, struct trace_probe, rp.kp); + struct trace_kprobe *tk = container_of(kp, struct trace_kprobe, rp.kp); - tp->nhit++; + tk->nhit++; - if (tp->flags & TP_FLAG_TRACE) - kprobe_trace_func(tp, regs); + if (tk->tp.flags & TP_FLAG_TRACE) + kprobe_trace_func(tk, regs); #ifdef CONFIG_PERF_EVENTS - if (tp->flags & TP_FLAG_PROFILE) - kprobe_perf_func(tp, regs); + if (tk->tp.flags & TP_FLAG_PROFILE) + kprobe_perf_func(tk, regs); #endif return 0; /* We don't tweek kernel, so just return 0 */ } @@ -1198,15 +1256,15 @@ int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs) static __kprobes int kretprobe_dispatcher(struct kretprobe_instance *ri, struct pt_regs *regs) { - struct trace_probe *tp = container_of(ri->rp, struct trace_probe, rp); + struct trace_kprobe *tk = container_of(ri->rp, struct trace_kprobe, rp); - tp->nhit++; + tk->nhit++; - if (tp->flags & TP_FLAG_TRACE) - kretprobe_trace_func(tp, ri, regs); + if (tk->tp.flags & TP_FLAG_TRACE) + kretprobe_trace_func(tk, ri, regs); #ifdef CONFIG_PERF_EVENTS - if (tp->flags & TP_FLAG_PROFILE) - kretprobe_perf_func(tp, ri, regs); + if (tk->tp.flags & TP_FLAG_PROFILE) + kretprobe_perf_func(tk, ri, regs); #endif return 0; /* We don't tweek kernel, so just return 0 */ } @@ -1219,21 +1277,21 @@ static struct trace_event_functions kprobe_funcs = { .trace = print_kprobe_event }; -static int register_probe_event(struct trace_probe *tp) +static int register_kprobe_event(struct trace_kprobe *tk) { - struct ftrace_event_call *call = &tp->call; + struct ftrace_event_call *call = &tk->tp.call; int ret; /* Initialize ftrace_event_call */ INIT_LIST_HEAD(&call->class->fields); - if (trace_probe_is_return(tp)) { + if (trace_kprobe_is_return(tk)) { call->event.funcs = &kretprobe_funcs; call->class->define_fields = kretprobe_event_define_fields; } else { call->event.funcs = &kprobe_funcs; call->class->define_fields = kprobe_event_define_fields; } - if (set_print_fmt(tp) < 0) + if (set_print_fmt(&tk->tp, trace_kprobe_is_return(tk)) < 0) return -ENOMEM; ret = register_ftrace_event(&call->event); if (!ret) { @@ -1242,7 +1300,7 @@ static int register_probe_event(struct trace_probe *tp) } call->flags = 0; call->class->reg = kprobe_register; - call->data = tp; + call->data = tk; ret = trace_add_event_call(call); if (ret) { pr_info("Failed to register kprobe event: %s\n", call->name); @@ -1252,14 +1310,14 @@ static int register_probe_event(struct trace_probe *tp) return ret; } -static int unregister_probe_event(struct trace_probe *tp) +static int unregister_kprobe_event(struct trace_kprobe *tk) { int ret; /* tp->event is unregistered in trace_remove_event_call() */ - ret = trace_remove_event_call(&tp->call); + ret = trace_remove_event_call(&tk->tp.call); if (!ret) - kfree(tp->call.print_fmt); + kfree(tk->tp.call.print_fmt); return ret; } @@ -1269,7 +1327,7 @@ static __init int init_kprobe_trace(void) struct dentry *d_tracer; struct dentry *entry; - if (register_module_notifier(&trace_probe_module_nb)) + if (register_module_notifier(&trace_kprobe_module_nb)) return -EINVAL; d_tracer = tracing_init_dentry(); @@ -1309,26 +1367,26 @@ static __used int kprobe_trace_selftest_target(int a1, int a2, int a3, } static struct ftrace_event_file * -find_trace_probe_file(struct trace_probe *tp, struct trace_array *tr) +find_trace_probe_file(struct trace_kprobe *tk, struct trace_array *tr) { struct ftrace_event_file *file; list_for_each_entry(file, &tr->events, list) - if (file->event_call == &tp->call) + if (file->event_call == &tk->tp.call) return file; return NULL; } /* - * Nobody but us can call enable_trace_probe/disable_trace_probe at this + * Nobody but us can call enable_trace_kprobe/disable_trace_kprobe at this * stage, we can do this lockless. */ static __init int kprobe_trace_self_tests_init(void) { int ret, warn = 0; int (*target)(int, int, int, int, int, int); - struct trace_probe *tp; + struct trace_kprobe *tk; struct ftrace_event_file *file; target = kprobe_trace_selftest_target; @@ -1337,44 +1395,44 @@ static __init int kprobe_trace_self_tests_init(void) ret = traceprobe_command("p:testprobe kprobe_trace_selftest_target " "$stack $stack0 +0($stack)", - create_trace_probe); + create_trace_kprobe); if (WARN_ON_ONCE(ret)) { pr_warn("error on probing function entry.\n"); warn++; } else { /* Enable trace point */ - tp = find_trace_probe("testprobe", KPROBE_EVENT_SYSTEM); - if (WARN_ON_ONCE(tp == NULL)) { + tk = find_trace_kprobe("testprobe", KPROBE_EVENT_SYSTEM); + if (WARN_ON_ONCE(tk == NULL)) { pr_warn("error on getting new probe.\n"); warn++; } else { - file = find_trace_probe_file(tp, top_trace_array()); + file = find_trace_probe_file(tk, top_trace_array()); if (WARN_ON_ONCE(file == NULL)) { pr_warn("error on getting probe file.\n"); warn++; } else - enable_trace_probe(tp, file); + enable_trace_kprobe(tk, file); } } ret = traceprobe_command("r:testprobe2 kprobe_trace_selftest_target " - "$retval", create_trace_probe); + "$retval", create_trace_kprobe); if (WARN_ON_ONCE(ret)) { pr_warn("error on probing function return.\n"); warn++; } else { /* Enable trace point */ - tp = find_trace_probe("testprobe2", KPROBE_EVENT_SYSTEM); - if (WARN_ON_ONCE(tp == NULL)) { + tk = find_trace_kprobe("testprobe2", KPROBE_EVENT_SYSTEM); + if (WARN_ON_ONCE(tk == NULL)) { pr_warn("error on getting 2nd new probe.\n"); warn++; } else { - file = find_trace_probe_file(tp, top_trace_array()); + file = find_trace_probe_file(tk, top_trace_array()); if (WARN_ON_ONCE(file == NULL)) { pr_warn("error on getting probe file.\n"); warn++; } else - enable_trace_probe(tp, file); + enable_trace_kprobe(tk, file); } } @@ -1384,46 +1442,46 @@ static __init int kprobe_trace_self_tests_init(void) ret = target(1, 2, 3, 4, 5, 6); /* Disable trace points before removing it */ - tp = find_trace_probe("testprobe", KPROBE_EVENT_SYSTEM); - if (WARN_ON_ONCE(tp == NULL)) { + tk = find_trace_kprobe("testprobe", KPROBE_EVENT_SYSTEM); + if (WARN_ON_ONCE(tk == NULL)) { pr_warn("error on getting test probe.\n"); warn++; } else { - file = find_trace_probe_file(tp, top_trace_array()); + file = find_trace_probe_file(tk, top_trace_array()); if (WARN_ON_ONCE(file == NULL)) { pr_warn("error on getting probe file.\n"); warn++; } else - disable_trace_probe(tp, file); + disable_trace_kprobe(tk, file); } - tp = find_trace_probe("testprobe2", KPROBE_EVENT_SYSTEM); - if (WARN_ON_ONCE(tp == NULL)) { + tk = find_trace_kprobe("testprobe2", KPROBE_EVENT_SYSTEM); + if (WARN_ON_ONCE(tk == NULL)) { pr_warn("error on getting 2nd test probe.\n"); warn++; } else { - file = find_trace_probe_file(tp, top_trace_array()); + file = find_trace_probe_file(tk, top_trace_array()); if (WARN_ON_ONCE(file == NULL)) { pr_warn("error on getting probe file.\n"); warn++; } else - disable_trace_probe(tp, file); + disable_trace_kprobe(tk, file); } - ret = traceprobe_command("-:testprobe", create_trace_probe); + ret = traceprobe_command("-:testprobe", create_trace_kprobe); if (WARN_ON_ONCE(ret)) { pr_warn("error on deleting a probe.\n"); warn++; } - ret = traceprobe_command("-:testprobe2", create_trace_probe); + ret = traceprobe_command("-:testprobe2", create_trace_kprobe); if (WARN_ON_ONCE(ret)) { pr_warn("error on deleting a probe.\n"); warn++; } end: - release_all_trace_probes(); + release_all_trace_kprobes(); if (warn) pr_cont("NG: Some tests are failed. Please check them.\n"); else diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c index 412e959..8364a42 100644 --- a/kernel/trace/trace_probe.c +++ b/kernel/trace/trace_probe.c @@ -35,46 +35,27 @@ const char *reserved_field_names[] = { FIELD_STRING_FUNC, }; -/* Printing function type */ -#define PRINT_TYPE_FUNC_NAME(type) print_type_##type -#define PRINT_TYPE_FMT_NAME(type) print_type_format_##type - /* Printing in basic type function template */ -#define DEFINE_BASIC_PRINT_TYPE_FUNC(type, fmt, cast) \ -static __kprobes int PRINT_TYPE_FUNC_NAME(type)(struct trace_seq *s, \ +#define DEFINE_BASIC_PRINT_TYPE_FUNC(type, fmt) \ +__kprobes int PRINT_TYPE_FUNC_NAME(type)(struct trace_seq *s, \ const char *name, \ - void *data, void *ent)\ + void *data, void *ent) \ { \ - return trace_seq_printf(s, " %s=" fmt, name, (cast)*(type *)data);\ + return trace_seq_printf(s, " %s=" fmt, name, *(type *)data); \ } \ -static const char PRINT_TYPE_FMT_NAME(type)[] = fmt; - -DEFINE_BASIC_PRINT_TYPE_FUNC(u8, "%x", unsigned int) -DEFINE_BASIC_PRINT_TYPE_FUNC(u16, "%x", unsigned int) -DEFINE_BASIC_PRINT_TYPE_FUNC(u32, "%lx", unsigned long) -DEFINE_BASIC_PRINT_TYPE_FUNC(u64, "%llx", unsigned long long) -DEFINE_BASIC_PRINT_TYPE_FUNC(s8, "%d", int) -DEFINE_BASIC_PRINT_TYPE_FUNC(s16, "%d", int) -DEFINE_BASIC_PRINT_TYPE_FUNC(s32, "%ld", long) -DEFINE_BASIC_PRINT_TYPE_FUNC(s64, "%lld", long long) - -static inline void *get_rloc_data(u32 *dl) -{ - return (u8 *)dl + get_rloc_offs(*dl); -} +const char PRINT_TYPE_FMT_NAME(type)[] = fmt; -/* For data_loc conversion */ -static inline void *get_loc_data(u32 *dl, void *ent) -{ - return (u8 *)ent + get_rloc_offs(*dl); -} - -/* For defining macros, define string/string_size types */ -typedef u32 string; -typedef u32 string_size; +DEFINE_BASIC_PRINT_TYPE_FUNC(u8 , "0x%x") +DEFINE_BASIC_PRINT_TYPE_FUNC(u16, "0x%x") +DEFINE_BASIC_PRINT_TYPE_FUNC(u32, "0x%x") +DEFINE_BASIC_PRINT_TYPE_FUNC(u64, "0x%Lx") +DEFINE_BASIC_PRINT_TYPE_FUNC(s8, "%d") +DEFINE_BASIC_PRINT_TYPE_FUNC(s16, "%d") +DEFINE_BASIC_PRINT_TYPE_FUNC(s32, "%d") +DEFINE_BASIC_PRINT_TYPE_FUNC(s64, "%Ld") /* Print type function for string type */ -static __kprobes int PRINT_TYPE_FUNC_NAME(string)(struct trace_seq *s, +__kprobes int PRINT_TYPE_FUNC_NAME(string)(struct trace_seq *s, const char *name, void *data, void *ent) { @@ -87,18 +68,7 @@ static __kprobes int PRINT_TYPE_FUNC_NAME(string)(struct trace_seq *s, (const char *)get_loc_data(data, ent)); } -static const char PRINT_TYPE_FMT_NAME(string)[] = "\\\"%s\\\""; - -#define FETCH_FUNC_NAME(method, type) fetch_##method##_##type -/* - * Define macro for basic types - we don't need to define s* types, because - * we have to care only about bitwidth at recording time. - */ -#define DEFINE_BASIC_FETCH_FUNCS(method) \ -DEFINE_FETCH_##method(u8) \ -DEFINE_FETCH_##method(u16) \ -DEFINE_FETCH_##method(u32) \ -DEFINE_FETCH_##method(u64) +const char PRINT_TYPE_FMT_NAME(string)[] = "\\\"%s\\\""; #define CHECK_FETCH_FUNCS(method, fn) \ (((FETCH_FUNC_NAME(method, u8) == fn) || \ @@ -111,7 +81,7 @@ DEFINE_FETCH_##method(u64) /* Data fetch function templates */ #define DEFINE_FETCH_reg(type) \ -static __kprobes void FETCH_FUNC_NAME(reg, type)(struct pt_regs *regs, \ +__kprobes void FETCH_FUNC_NAME(reg, type)(struct pt_regs *regs, \ void *offset, void *dest) \ { \ *(type *)dest = (type)regs_get_register(regs, \ @@ -122,20 +92,8 @@ DEFINE_BASIC_FETCH_FUNCS(reg) #define fetch_reg_string NULL #define fetch_reg_string_size NULL -#define DEFINE_FETCH_stack(type) \ -static __kprobes void FETCH_FUNC_NAME(stack, type)(struct pt_regs *regs,\ - void *offset, void *dest) \ -{ \ - *(type *)dest = (type)regs_get_kernel_stack_nth(regs, \ - (unsigned int)((unsigned long)offset)); \ -} -DEFINE_BASIC_FETCH_FUNCS(stack) -/* No string on the stack entry */ -#define fetch_stack_string NULL -#define fetch_stack_string_size NULL - #define DEFINE_FETCH_retval(type) \ -static __kprobes void FETCH_FUNC_NAME(retval, type)(struct pt_regs *regs,\ +__kprobes void FETCH_FUNC_NAME(retval, type)(struct pt_regs *regs, \ void *dummy, void *dest) \ { \ *(type *)dest = (type)regs_return_value(regs); \ @@ -145,150 +103,16 @@ DEFINE_BASIC_FETCH_FUNCS(retval) #define fetch_retval_string NULL #define fetch_retval_string_size NULL -#define DEFINE_FETCH_memory(type) \ -static __kprobes void FETCH_FUNC_NAME(memory, type)(struct pt_regs *regs,\ - void *addr, void *dest) \ -{ \ - type retval; \ - if (probe_kernel_address(addr, retval)) \ - *(type *)dest = 0; \ - else \ - *(type *)dest = retval; \ -} -DEFINE_BASIC_FETCH_FUNCS(memory) -/* - * Fetch a null-terminated string. Caller MUST set *(u32 *)dest with max - * length and relative data location. - */ -static __kprobes void FETCH_FUNC_NAME(memory, string)(struct pt_regs *regs, - void *addr, void *dest) -{ - long ret; - int maxlen = get_rloc_len(*(u32 *)dest); - u8 *dst = get_rloc_data(dest); - u8 *src = addr; - mm_segment_t old_fs = get_fs(); - - if (!maxlen) - return; - - /* - * Try to get string again, since the string can be changed while - * probing. - */ - set_fs(KERNEL_DS); - pagefault_disable(); - - do - ret = __copy_from_user_inatomic(dst++, src++, 1); - while (dst[-1] && ret == 0 && src - (u8 *)addr < maxlen); - - dst[-1] = '\0'; - pagefault_enable(); - set_fs(old_fs); - - if (ret < 0) { /* Failed to fetch string */ - ((u8 *)get_rloc_data(dest))[0] = '\0'; - *(u32 *)dest = make_data_rloc(0, get_rloc_offs(*(u32 *)dest)); - } else { - *(u32 *)dest = make_data_rloc(src - (u8 *)addr, - get_rloc_offs(*(u32 *)dest)); - } -} - -/* Return the length of string -- including null terminal byte */ -static __kprobes void FETCH_FUNC_NAME(memory, string_size)(struct pt_regs *regs, - void *addr, void *dest) -{ - mm_segment_t old_fs; - int ret, len = 0; - u8 c; - - old_fs = get_fs(); - set_fs(KERNEL_DS); - pagefault_disable(); - - do { - ret = __copy_from_user_inatomic(&c, (u8 *)addr + len, 1); - len++; - } while (c && ret == 0 && len < MAX_STRING_SIZE); - - pagefault_enable(); - set_fs(old_fs); - - if (ret < 0) /* Failed to check the length */ - *(u32 *)dest = 0; - else - *(u32 *)dest = len; -} - -/* Memory fetching by symbol */ -struct symbol_cache { - char *symbol; - long offset; - unsigned long addr; -}; - -static unsigned long update_symbol_cache(struct symbol_cache *sc) -{ - sc->addr = (unsigned long)kallsyms_lookup_name(sc->symbol); - - if (sc->addr) - sc->addr += sc->offset; - - return sc->addr; -} - -static void free_symbol_cache(struct symbol_cache *sc) -{ - kfree(sc->symbol); - kfree(sc); -} - -static struct symbol_cache *alloc_symbol_cache(const char *sym, long offset) -{ - struct symbol_cache *sc; - - if (!sym || strlen(sym) == 0) - return NULL; - - sc = kzalloc(sizeof(struct symbol_cache), GFP_KERNEL); - if (!sc) - return NULL; - - sc->symbol = kstrdup(sym, GFP_KERNEL); - if (!sc->symbol) { - kfree(sc); - return NULL; - } - sc->offset = offset; - update_symbol_cache(sc); - - return sc; -} - -#define DEFINE_FETCH_symbol(type) \ -static __kprobes void FETCH_FUNC_NAME(symbol, type)(struct pt_regs *regs,\ - void *data, void *dest) \ -{ \ - struct symbol_cache *sc = data; \ - if (sc->addr) \ - fetch_memory_##type(regs, (void *)sc->addr, dest); \ - else \ - *(type *)dest = 0; \ -} -DEFINE_BASIC_FETCH_FUNCS(symbol) -DEFINE_FETCH_symbol(string) -DEFINE_FETCH_symbol(string_size) - /* Dereference memory access function */ struct deref_fetch_param { struct fetch_param orig; long offset; + fetch_func_t fetch; + fetch_func_t fetch_size; }; #define DEFINE_FETCH_deref(type) \ -static __kprobes void FETCH_FUNC_NAME(deref, type)(struct pt_regs *regs,\ +__kprobes void FETCH_FUNC_NAME(deref, type)(struct pt_regs *regs, \ void *data, void *dest) \ { \ struct deref_fetch_param *dprm = data; \ @@ -296,13 +120,26 @@ static __kprobes void FETCH_FUNC_NAME(deref, type)(struct pt_regs *regs,\ call_fetch(&dprm->orig, regs, &addr); \ if (addr) { \ addr += dprm->offset; \ - fetch_memory_##type(regs, (void *)addr, dest); \ + dprm->fetch(regs, (void *)addr, dest); \ } else \ *(type *)dest = 0; \ } DEFINE_BASIC_FETCH_FUNCS(deref) DEFINE_FETCH_deref(string) -DEFINE_FETCH_deref(string_size) + +__kprobes void FETCH_FUNC_NAME(deref, string_size)(struct pt_regs *regs, + void *data, void *dest) +{ + struct deref_fetch_param *dprm = data; + unsigned long addr; + + call_fetch(&dprm->orig, regs, &addr); + if (addr && dprm->fetch_size) { + addr += dprm->offset; + dprm->fetch_size(regs, (void *)addr, dest); + } else + *(string_size *)dest = 0; +} static __kprobes void update_deref_fetch_param(struct deref_fetch_param *data) { @@ -329,7 +166,7 @@ struct bitfield_fetch_param { }; #define DEFINE_FETCH_bitfield(type) \ -static __kprobes void FETCH_FUNC_NAME(bitfield, type)(struct pt_regs *regs,\ +__kprobes void FETCH_FUNC_NAME(bitfield, type)(struct pt_regs *regs, \ void *data, void *dest) \ { \ struct bitfield_fetch_param *bprm = data; \ @@ -374,58 +211,8 @@ free_bitfield_fetch_param(struct bitfield_fetch_param *data) kfree(data); } -/* Default (unsigned long) fetch type */ -#define __DEFAULT_FETCH_TYPE(t) u##t -#define _DEFAULT_FETCH_TYPE(t) __DEFAULT_FETCH_TYPE(t) -#define DEFAULT_FETCH_TYPE _DEFAULT_FETCH_TYPE(BITS_PER_LONG) -#define DEFAULT_FETCH_TYPE_STR __stringify(DEFAULT_FETCH_TYPE) - -#define ASSIGN_FETCH_FUNC(method, type) \ - [FETCH_MTD_##method] = FETCH_FUNC_NAME(method, type) - -#define __ASSIGN_FETCH_TYPE(_name, ptype, ftype, _size, sign, _fmttype) \ - {.name = _name, \ - .size = _size, \ - .is_signed = sign, \ - .print = PRINT_TYPE_FUNC_NAME(ptype), \ - .fmt = PRINT_TYPE_FMT_NAME(ptype), \ - .fmttype = _fmttype, \ - .fetch = { \ -ASSIGN_FETCH_FUNC(reg, ftype), \ -ASSIGN_FETCH_FUNC(stack, ftype), \ -ASSIGN_FETCH_FUNC(retval, ftype), \ -ASSIGN_FETCH_FUNC(memory, ftype), \ -ASSIGN_FETCH_FUNC(symbol, ftype), \ -ASSIGN_FETCH_FUNC(deref, ftype), \ -ASSIGN_FETCH_FUNC(bitfield, ftype), \ - } \ - } - -#define ASSIGN_FETCH_TYPE(ptype, ftype, sign) \ - __ASSIGN_FETCH_TYPE(#ptype, ptype, ftype, sizeof(ftype), sign, #ptype) - -#define FETCH_TYPE_STRING 0 -#define FETCH_TYPE_STRSIZE 1 - -/* Fetch type information table */ -static const struct fetch_type fetch_type_table[] = { - /* Special types */ - [FETCH_TYPE_STRING] = __ASSIGN_FETCH_TYPE("string", string, string, - sizeof(u32), 1, "__data_loc char[]"), - [FETCH_TYPE_STRSIZE] = __ASSIGN_FETCH_TYPE("string_size", u32, - string_size, sizeof(u32), 0, "u32"), - /* Basic types */ - ASSIGN_FETCH_TYPE(u8, u8, 0), - ASSIGN_FETCH_TYPE(u16, u16, 0), - ASSIGN_FETCH_TYPE(u32, u32, 0), - ASSIGN_FETCH_TYPE(u64, u64, 0), - ASSIGN_FETCH_TYPE(s8, u8, 1), - ASSIGN_FETCH_TYPE(s16, u16, 1), - ASSIGN_FETCH_TYPE(s32, u32, 1), - ASSIGN_FETCH_TYPE(s64, u64, 1), -}; - -static const struct fetch_type *find_fetch_type(const char *type) +static const struct fetch_type *find_fetch_type(const char *type, + const struct fetch_type *ftbl) { int i; @@ -446,44 +233,52 @@ static const struct fetch_type *find_fetch_type(const char *type) switch (bs) { case 8: - return find_fetch_type("u8"); + return find_fetch_type("u8", ftbl); case 16: - return find_fetch_type("u16"); + return find_fetch_type("u16", ftbl); case 32: - return find_fetch_type("u32"); + return find_fetch_type("u32", ftbl); case 64: - return find_fetch_type("u64"); + return find_fetch_type("u64", ftbl); default: goto fail; } } - for (i = 0; i < ARRAY_SIZE(fetch_type_table); i++) - if (strcmp(type, fetch_type_table[i].name) == 0) - return &fetch_type_table[i]; + for (i = 0; ftbl[i].name; i++) { + if (strcmp(type, ftbl[i].name) == 0) + return &ftbl[i]; + } fail: return NULL; } /* Special function : only accept unsigned long */ -static __kprobes void fetch_stack_address(struct pt_regs *regs, - void *dummy, void *dest) +static __kprobes void fetch_kernel_stack_address(struct pt_regs *regs, + void *dummy, void *dest) { *(unsigned long *)dest = kernel_stack_pointer(regs); } +static __kprobes void fetch_user_stack_address(struct pt_regs *regs, + void *dummy, void *dest) +{ + *(unsigned long *)dest = user_stack_pointer(regs); +} + static fetch_func_t get_fetch_size_function(const struct fetch_type *type, - fetch_func_t orig_fn) + fetch_func_t orig_fn, + const struct fetch_type *ftbl) { int i; - if (type != &fetch_type_table[FETCH_TYPE_STRING]) + if (type != &ftbl[FETCH_TYPE_STRING]) return NULL; /* Only string type needs size function */ for (i = 0; i < FETCH_MTD_END; i++) if (type->fetch[i] == orig_fn) - return fetch_type_table[FETCH_TYPE_STRSIZE].fetch[i]; + return ftbl[FETCH_TYPE_STRSIZE].fetch[i]; WARN_ON(1); /* This should not happen */ @@ -516,7 +311,8 @@ int traceprobe_split_symbol_offset(char *symbol, unsigned long *offset) #define PARAM_MAX_STACK (THREAD_SIZE / sizeof(unsigned long)) static int parse_probe_vars(char *arg, const struct fetch_type *t, - struct fetch_param *f, bool is_return) + struct fetch_param *f, bool is_return, + bool is_kprobe) { int ret = 0; unsigned long param; @@ -528,13 +324,16 @@ static int parse_probe_vars(char *arg, const struct fetch_type *t, ret = -EINVAL; } else if (strncmp(arg, "stack", 5) == 0) { if (arg[5] == '\0') { - if (strcmp(t->name, DEFAULT_FETCH_TYPE_STR) == 0) - f->fn = fetch_stack_address; + if (strcmp(t->name, DEFAULT_FETCH_TYPE_STR)) + return -EINVAL; + + if (is_kprobe) + f->fn = fetch_kernel_stack_address; else - ret = -EINVAL; + f->fn = fetch_user_stack_address; } else if (isdigit(arg[5])) { ret = kstrtoul(arg + 5, 10, ¶m); - if (ret || param > PARAM_MAX_STACK) + if (ret || (is_kprobe && param > PARAM_MAX_STACK)) ret = -EINVAL; else { f->fn = t->fetch[FETCH_MTD_stack]; @@ -552,20 +351,18 @@ static int parse_probe_vars(char *arg, const struct fetch_type *t, static int parse_probe_arg(char *arg, const struct fetch_type *t, struct fetch_param *f, bool is_return, bool is_kprobe) { + const struct fetch_type *ftbl; unsigned long param; long offset; char *tmp; - int ret; - - ret = 0; + int ret = 0; - /* Until uprobe_events supports only reg arguments */ - if (!is_kprobe && arg[0] != '%') - return -EINVAL; + ftbl = is_kprobe ? kprobes_fetch_type_table : uprobes_fetch_type_table; + BUG_ON(ftbl == NULL); switch (arg[0]) { case '$': - ret = parse_probe_vars(arg + 1, t, f, is_return); + ret = parse_probe_vars(arg + 1, t, f, is_return, is_kprobe); break; case '%': /* named register */ @@ -577,7 +374,7 @@ static int parse_probe_arg(char *arg, const struct fetch_type *t, } break; - case '@': /* memory or symbol */ + case '@': /* memory, file-offset or symbol */ if (isdigit(arg[1])) { ret = kstrtoul(arg + 1, 0, ¶m); if (ret) @@ -585,7 +382,22 @@ static int parse_probe_arg(char *arg, const struct fetch_type *t, f->fn = t->fetch[FETCH_MTD_memory]; f->data = (void *)param; + } else if (arg[1] == '+') { + /* kprobes don't support file offsets */ + if (is_kprobe) + return -EINVAL; + + ret = kstrtol(arg + 2, 0, &offset); + if (ret) + break; + + f->fn = t->fetch[FETCH_MTD_file_offset]; + f->data = (void *)offset; } else { + /* uprobes don't support symbols */ + if (!is_kprobe) + return -EINVAL; + ret = traceprobe_split_symbol_offset(arg + 1, &offset); if (ret) break; @@ -616,7 +428,7 @@ static int parse_probe_arg(char *arg, const struct fetch_type *t, struct deref_fetch_param *dprm; const struct fetch_type *t2; - t2 = find_fetch_type(NULL); + t2 = find_fetch_type(NULL, ftbl); *tmp = '\0'; dprm = kzalloc(sizeof(struct deref_fetch_param), GFP_KERNEL); @@ -624,6 +436,9 @@ static int parse_probe_arg(char *arg, const struct fetch_type *t, return -ENOMEM; dprm->offset = offset; + dprm->fetch = t->fetch[FETCH_MTD_memory]; + dprm->fetch_size = get_fetch_size_function(t, + dprm->fetch, ftbl); ret = parse_probe_arg(arg, t2, &dprm->orig, is_return, is_kprobe); if (ret) @@ -685,9 +500,13 @@ static int __parse_bitfield_probe_arg(const char *bf, int traceprobe_parse_probe_arg(char *arg, ssize_t *size, struct probe_arg *parg, bool is_return, bool is_kprobe) { + const struct fetch_type *ftbl; const char *t; int ret; + ftbl = is_kprobe ? kprobes_fetch_type_table : uprobes_fetch_type_table; + BUG_ON(ftbl == NULL); + if (strlen(arg) > MAX_ARGSTR_LEN) { pr_info("Argument is too long.: %s\n", arg); return -ENOSPC; @@ -702,7 +521,7 @@ int traceprobe_parse_probe_arg(char *arg, ssize_t *size, arg[t - parg->comm] = '\0'; t++; } - parg->type = find_fetch_type(t); + parg->type = find_fetch_type(t, ftbl); if (!parg->type) { pr_info("Unsupported type: %s\n", t); return -EINVAL; @@ -716,7 +535,8 @@ int traceprobe_parse_probe_arg(char *arg, ssize_t *size, if (ret >= 0) { parg->fetch_size.fn = get_fetch_size_function(parg->type, - parg->fetch.fn); + parg->fetch.fn, + ftbl); parg->fetch_size.data = parg->fetch.data; } @@ -837,3 +657,65 @@ out: return ret; } + +static int __set_print_fmt(struct trace_probe *tp, char *buf, int len, + bool is_return) +{ + int i; + int pos = 0; + + const char *fmt, *arg; + + if (!is_return) { + fmt = "(%lx)"; + arg = "REC->" FIELD_STRING_IP; + } else { + fmt = "(%lx <- %lx)"; + arg = "REC->" FIELD_STRING_FUNC ", REC->" FIELD_STRING_RETIP; + } + + /* When len=0, we just calculate the needed length */ +#define LEN_OR_ZERO (len ? len - pos : 0) + + pos += snprintf(buf + pos, LEN_OR_ZERO, "\"%s", fmt); + + for (i = 0; i < tp->nr_args; i++) { + pos += snprintf(buf + pos, LEN_OR_ZERO, " %s=%s", + tp->args[i].name, tp->args[i].type->fmt); + } + + pos += snprintf(buf + pos, LEN_OR_ZERO, "\", %s", arg); + + for (i = 0; i < tp->nr_args; i++) { + if (strcmp(tp->args[i].type->name, "string") == 0) + pos += snprintf(buf + pos, LEN_OR_ZERO, + ", __get_str(%s)", + tp->args[i].name); + else + pos += snprintf(buf + pos, LEN_OR_ZERO, ", REC->%s", + tp->args[i].name); + } + +#undef LEN_OR_ZERO + + /* return the length of print_fmt */ + return pos; +} + +int set_print_fmt(struct trace_probe *tp, bool is_return) +{ + int len; + char *print_fmt; + + /* First: called with 0 length to calculate the needed length */ + len = __set_print_fmt(tp, NULL, 0, is_return); + print_fmt = kmalloc(len + 1, GFP_KERNEL); + if (!print_fmt) + return -ENOMEM; + + /* Second: actually write the @print_fmt */ + __set_print_fmt(tp, print_fmt, len + 1, is_return); + tp->call.print_fmt = print_fmt; + + return 0; +} diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h index 5c7e09d..b73574a 100644 --- a/kernel/trace/trace_probe.h +++ b/kernel/trace/trace_probe.h @@ -81,6 +81,17 @@ */ #define convert_rloc_to_loc(dl, offs) ((u32)(dl) + (offs)) +static inline void *get_rloc_data(u32 *dl) +{ + return (u8 *)dl + get_rloc_offs(*dl); +} + +/* For data_loc conversion */ +static inline void *get_loc_data(u32 *dl, void *ent) +{ + return (u8 *)ent + get_rloc_offs(*dl); +} + /* Data fetch function type */ typedef void (*fetch_func_t)(struct pt_regs *, void *, void *); /* Printing function type */ @@ -95,6 +106,7 @@ enum { FETCH_MTD_symbol, FETCH_MTD_deref, FETCH_MTD_bitfield, + FETCH_MTD_file_offset, FETCH_MTD_END, }; @@ -115,6 +127,148 @@ struct fetch_param { void *data; }; +/* For defining macros, define string/string_size types */ +typedef u32 string; +typedef u32 string_size; + +#define PRINT_TYPE_FUNC_NAME(type) print_type_##type +#define PRINT_TYPE_FMT_NAME(type) print_type_format_##type + +/* Printing in basic type function template */ +#define DECLARE_BASIC_PRINT_TYPE_FUNC(type) \ +__kprobes int PRINT_TYPE_FUNC_NAME(type)(struct trace_seq *s, \ + const char *name, \ + void *data, void *ent); \ +extern const char PRINT_TYPE_FMT_NAME(type)[] + +DECLARE_BASIC_PRINT_TYPE_FUNC(u8); +DECLARE_BASIC_PRINT_TYPE_FUNC(u16); +DECLARE_BASIC_PRINT_TYPE_FUNC(u32); +DECLARE_BASIC_PRINT_TYPE_FUNC(u64); +DECLARE_BASIC_PRINT_TYPE_FUNC(s8); +DECLARE_BASIC_PRINT_TYPE_FUNC(s16); +DECLARE_BASIC_PRINT_TYPE_FUNC(s32); +DECLARE_BASIC_PRINT_TYPE_FUNC(s64); +DECLARE_BASIC_PRINT_TYPE_FUNC(string); + +#define FETCH_FUNC_NAME(method, type) fetch_##method##_##type + +/* Declare macro for basic types */ +#define DECLARE_FETCH_FUNC(method, type) \ +extern void FETCH_FUNC_NAME(method, type)(struct pt_regs *regs, \ + void *data, void *dest) + +#define DECLARE_BASIC_FETCH_FUNCS(method) \ +DECLARE_FETCH_FUNC(method, u8); \ +DECLARE_FETCH_FUNC(method, u16); \ +DECLARE_FETCH_FUNC(method, u32); \ +DECLARE_FETCH_FUNC(method, u64) + +DECLARE_BASIC_FETCH_FUNCS(reg); +#define fetch_reg_string NULL +#define fetch_reg_string_size NULL + +DECLARE_BASIC_FETCH_FUNCS(retval); +#define fetch_retval_string NULL +#define fetch_retval_string_size NULL + +DECLARE_BASIC_FETCH_FUNCS(symbol); +DECLARE_FETCH_FUNC(symbol, string); +DECLARE_FETCH_FUNC(symbol, string_size); + +DECLARE_BASIC_FETCH_FUNCS(deref); +DECLARE_FETCH_FUNC(deref, string); +DECLARE_FETCH_FUNC(deref, string_size); + +DECLARE_BASIC_FETCH_FUNCS(bitfield); +#define fetch_bitfield_string NULL +#define fetch_bitfield_string_size NULL + +/* + * Define macro for basic types - we don't need to define s* types, because + * we have to care only about bitwidth at recording time. + */ +#define DEFINE_BASIC_FETCH_FUNCS(method) \ +DEFINE_FETCH_##method(u8) \ +DEFINE_FETCH_##method(u16) \ +DEFINE_FETCH_##method(u32) \ +DEFINE_FETCH_##method(u64) + +/* Default (unsigned long) fetch type */ +#define __DEFAULT_FETCH_TYPE(t) u##t +#define _DEFAULT_FETCH_TYPE(t) __DEFAULT_FETCH_TYPE(t) +#define DEFAULT_FETCH_TYPE _DEFAULT_FETCH_TYPE(BITS_PER_LONG) +#define DEFAULT_FETCH_TYPE_STR __stringify(DEFAULT_FETCH_TYPE) + +#define ASSIGN_FETCH_FUNC(method, type) \ + [FETCH_MTD_##method] = FETCH_FUNC_NAME(method, type) + +#define __ASSIGN_FETCH_TYPE(_name, ptype, ftype, _size, sign, _fmttype) \ + {.name = _name, \ + .size = _size, \ + .is_signed = sign, \ + .print = PRINT_TYPE_FUNC_NAME(ptype), \ + .fmt = PRINT_TYPE_FMT_NAME(ptype), \ + .fmttype = _fmttype, \ + .fetch = { \ +ASSIGN_FETCH_FUNC(reg, ftype), \ +ASSIGN_FETCH_FUNC(stack, ftype), \ +ASSIGN_FETCH_FUNC(retval, ftype), \ +ASSIGN_FETCH_FUNC(memory, ftype), \ +ASSIGN_FETCH_FUNC(symbol, ftype), \ +ASSIGN_FETCH_FUNC(deref, ftype), \ +ASSIGN_FETCH_FUNC(bitfield, ftype), \ +ASSIGN_FETCH_FUNC(file_offset, ftype), \ + } \ + } + +#define ASSIGN_FETCH_TYPE(ptype, ftype, sign) \ + __ASSIGN_FETCH_TYPE(#ptype, ptype, ftype, sizeof(ftype), sign, #ptype) + +#define ASSIGN_FETCH_TYPE_END {} + +#define FETCH_TYPE_STRING 0 +#define FETCH_TYPE_STRSIZE 1 + +/* + * Fetch type information table. + * It's declared as a weak symbol due to conditional compilation. + */ +extern __weak const struct fetch_type kprobes_fetch_type_table[]; +extern __weak const struct fetch_type uprobes_fetch_type_table[]; + +#ifdef CONFIG_KPROBE_EVENT +struct symbol_cache; +unsigned long update_symbol_cache(struct symbol_cache *sc); +void free_symbol_cache(struct symbol_cache *sc); +struct symbol_cache *alloc_symbol_cache(const char *sym, long offset); +#else +/* uprobes do not support symbol fetch methods */ +#define fetch_symbol_u8 NULL +#define fetch_symbol_u16 NULL +#define fetch_symbol_u32 NULL +#define fetch_symbol_u64 NULL +#define fetch_symbol_string NULL +#define fetch_symbol_string_size NULL + +struct symbol_cache { +}; +static inline unsigned long __used update_symbol_cache(struct symbol_cache *sc) +{ + return 0; +} + +static inline void __used free_symbol_cache(struct symbol_cache *sc) +{ +} + +static inline struct symbol_cache * __used +alloc_symbol_cache(const char *sym, long offset) +{ + return NULL; +} +#endif /* CONFIG_KPROBE_EVENT */ + struct probe_arg { struct fetch_param fetch; struct fetch_param fetch_size; @@ -124,6 +278,26 @@ struct probe_arg { const struct fetch_type *type; /* Type of this argument */ }; +struct trace_probe { + unsigned int flags; /* For TP_FLAG_* */ + struct ftrace_event_class class; + struct ftrace_event_call call; + struct list_head files; + ssize_t size; /* trace entry size */ + unsigned int nr_args; + struct probe_arg args[]; +}; + +static inline bool trace_probe_is_enabled(struct trace_probe *tp) +{ + return !!(tp->flags & (TP_FLAG_TRACE | TP_FLAG_PROFILE)); +} + +static inline bool trace_probe_is_registered(struct trace_probe *tp) +{ + return !!(tp->flags & TP_FLAG_REGISTERED); +} + static inline __kprobes void call_fetch(struct fetch_param *fprm, struct pt_regs *regs, void *dest) { @@ -158,3 +332,53 @@ extern ssize_t traceprobe_probes_write(struct file *file, int (*createfn)(int, char**)); extern int traceprobe_command(const char *buf, int (*createfn)(int, char**)); + +/* Sum up total data length for dynamic arraies (strings) */ +static inline __kprobes int +__get_data_size(struct trace_probe *tp, struct pt_regs *regs) +{ + int i, ret = 0; + u32 len; + + for (i = 0; i < tp->nr_args; i++) + if (unlikely(tp->args[i].fetch_size.fn)) { + call_fetch(&tp->args[i].fetch_size, regs, &len); + ret += len; + } + + return ret; +} + +/* Store the value of each argument */ +static inline __kprobes void +store_trace_args(int ent_size, struct trace_probe *tp, struct pt_regs *regs, + u8 *data, int maxlen) +{ + int i; + u32 end = tp->size; + u32 *dl; /* Data (relative) location */ + + for (i = 0; i < tp->nr_args; i++) { + if (unlikely(tp->args[i].fetch_size.fn)) { + /* + * First, we set the relative location and + * maximum data length to *dl + */ + dl = (u32 *)(data + tp->args[i].offset); + *dl = make_data_rloc(maxlen, end - tp->args[i].offset); + /* Then try to fetch string or dynamic array data */ + call_fetch(&tp->args[i].fetch, regs, dl); + /* Reduce maximum length */ + end += get_rloc_len(*dl); + maxlen -= get_rloc_len(*dl); + /* Trick here, convert data_rloc to data_loc */ + *dl = convert_rloc_to_loc(*dl, + ent_size + tp->args[i].offset); + } else + /* Just fetching data normally */ + call_fetch(&tp->args[i].fetch, regs, + data + tp->args[i].offset); + } +} + +extern int set_print_fmt(struct trace_probe *tp, bool is_return); diff --git a/kernel/trace/trace_stack.c b/kernel/trace/trace_stack.c index b20428c..e6be585 100644 --- a/kernel/trace/trace_stack.c +++ b/kernel/trace/trace_stack.c @@ -382,7 +382,7 @@ static const struct file_operations stack_trace_filter_fops = { .open = stack_trace_filter_open, .read = seq_read, .write = ftrace_filter_write, - .llseek = ftrace_filter_lseek, + .llseek = tracing_lseek, .release = ftrace_regex_release, }; diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c index ea90eb5..759d5e0 100644 --- a/kernel/trace/trace_syscalls.c +++ b/kernel/trace/trace_syscalls.c @@ -321,7 +321,7 @@ static void ftrace_syscall_enter(void *data, struct pt_regs *regs, long id) if (!ftrace_file) return; - if (test_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, &ftrace_file->flags)) + if (ftrace_trigger_soft_disabled(ftrace_file)) return; sys_data = syscall_nr_to_meta(syscall_nr); @@ -343,9 +343,8 @@ static void ftrace_syscall_enter(void *data, struct pt_regs *regs, long id) entry->nr = syscall_nr; syscall_get_arguments(current, regs, 0, sys_data->nb_args, entry->args); - if (!filter_check_discard(ftrace_file, entry, buffer, event)) - trace_current_buffer_unlock_commit(buffer, event, - irq_flags, pc); + event_trigger_unlock_commit(ftrace_file, buffer, event, entry, + irq_flags, pc); } static void ftrace_syscall_exit(void *data, struct pt_regs *regs, long ret) @@ -369,7 +368,7 @@ static void ftrace_syscall_exit(void *data, struct pt_regs *regs, long ret) if (!ftrace_file) return; - if (test_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, &ftrace_file->flags)) + if (ftrace_trigger_soft_disabled(ftrace_file)) return; sys_data = syscall_nr_to_meta(syscall_nr); @@ -390,9 +389,8 @@ static void ftrace_syscall_exit(void *data, struct pt_regs *regs, long ret) entry->nr = syscall_nr; entry->ret = syscall_get_return_value(current, regs); - if (!filter_check_discard(ftrace_file, entry, buffer, event)) - trace_current_buffer_unlock_commit(buffer, event, - irq_flags, pc); + event_trigger_unlock_commit(ftrace_file, buffer, event, entry, + irq_flags, pc); } static int reg_event_syscall_enter(struct ftrace_event_file *file, diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c index b6dcc42..79e52d9 100644 --- a/kernel/trace/trace_uprobe.c +++ b/kernel/trace/trace_uprobe.c @@ -51,22 +51,17 @@ struct trace_uprobe_filter { */ struct trace_uprobe { struct list_head list; - struct ftrace_event_class class; - struct ftrace_event_call call; struct trace_uprobe_filter filter; struct uprobe_consumer consumer; struct inode *inode; char *filename; unsigned long offset; unsigned long nhit; - unsigned int flags; /* For TP_FLAG_* */ - ssize_t size; /* trace entry size */ - unsigned int nr_args; - struct probe_arg args[]; + struct trace_probe tp; }; -#define SIZEOF_TRACE_UPROBE(n) \ - (offsetof(struct trace_uprobe, args) + \ +#define SIZEOF_TRACE_UPROBE(n) \ + (offsetof(struct trace_uprobe, tp.args) + \ (sizeof(struct probe_arg) * (n))) static int register_uprobe_event(struct trace_uprobe *tu); @@ -75,10 +70,151 @@ static int unregister_uprobe_event(struct trace_uprobe *tu); static DEFINE_MUTEX(uprobe_lock); static LIST_HEAD(uprobe_list); +struct uprobe_dispatch_data { + struct trace_uprobe *tu; + unsigned long bp_addr; +}; + static int uprobe_dispatcher(struct uprobe_consumer *con, struct pt_regs *regs); static int uretprobe_dispatcher(struct uprobe_consumer *con, unsigned long func, struct pt_regs *regs); +#ifdef CONFIG_STACK_GROWSUP +static unsigned long adjust_stack_addr(unsigned long addr, unsigned int n) +{ + return addr - (n * sizeof(long)); +} +#else +static unsigned long adjust_stack_addr(unsigned long addr, unsigned int n) +{ + return addr + (n * sizeof(long)); +} +#endif + +static unsigned long get_user_stack_nth(struct pt_regs *regs, unsigned int n) +{ + unsigned long ret; + unsigned long addr = user_stack_pointer(regs); + + addr = adjust_stack_addr(addr, n); + + if (copy_from_user(&ret, (void __force __user *) addr, sizeof(ret))) + return 0; + + return ret; +} + +/* + * Uprobes-specific fetch functions + */ +#define DEFINE_FETCH_stack(type) \ +static __kprobes void FETCH_FUNC_NAME(stack, type)(struct pt_regs *regs,\ + void *offset, void *dest) \ +{ \ + *(type *)dest = (type)get_user_stack_nth(regs, \ + ((unsigned long)offset)); \ +} +DEFINE_BASIC_FETCH_FUNCS(stack) +/* No string on the stack entry */ +#define fetch_stack_string NULL +#define fetch_stack_string_size NULL + +#define DEFINE_FETCH_memory(type) \ +static __kprobes void FETCH_FUNC_NAME(memory, type)(struct pt_regs *regs,\ + void *addr, void *dest) \ +{ \ + type retval; \ + void __user *vaddr = (void __force __user *) addr; \ + \ + if (copy_from_user(&retval, vaddr, sizeof(type))) \ + *(type *)dest = 0; \ + else \ + *(type *) dest = retval; \ +} +DEFINE_BASIC_FETCH_FUNCS(memory) +/* + * Fetch a null-terminated string. Caller MUST set *(u32 *)dest with max + * length and relative data location. + */ +static __kprobes void FETCH_FUNC_NAME(memory, string)(struct pt_regs *regs, + void *addr, void *dest) +{ + long ret; + u32 rloc = *(u32 *)dest; + int maxlen = get_rloc_len(rloc); + u8 *dst = get_rloc_data(dest); + void __user *src = (void __force __user *) addr; + + if (!maxlen) + return; + + ret = strncpy_from_user(dst, src, maxlen); + + if (ret < 0) { /* Failed to fetch string */ + ((u8 *)get_rloc_data(dest))[0] = '\0'; + *(u32 *)dest = make_data_rloc(0, get_rloc_offs(rloc)); + } else { + *(u32 *)dest = make_data_rloc(ret, get_rloc_offs(rloc)); + } +} + +static __kprobes void FETCH_FUNC_NAME(memory, string_size)(struct pt_regs *regs, + void *addr, void *dest) +{ + int len; + void __user *vaddr = (void __force __user *) addr; + + len = strnlen_user(vaddr, MAX_STRING_SIZE); + + if (len == 0 || len > MAX_STRING_SIZE) /* Failed to check length */ + *(u32 *)dest = 0; + else + *(u32 *)dest = len; +} + +static unsigned long translate_user_vaddr(void *file_offset) +{ + unsigned long base_addr; + struct uprobe_dispatch_data *udd; + + udd = (void *) current->utask->vaddr; + + base_addr = udd->bp_addr - udd->tu->offset; + return base_addr + (unsigned long)file_offset; +} + +#define DEFINE_FETCH_file_offset(type) \ +static __kprobes void FETCH_FUNC_NAME(file_offset, type)(struct pt_regs *regs,\ + void *offset, void *dest) \ +{ \ + void *vaddr = (void *)translate_user_vaddr(offset); \ + \ + FETCH_FUNC_NAME(memory, type)(regs, vaddr, dest); \ +} +DEFINE_BASIC_FETCH_FUNCS(file_offset) +DEFINE_FETCH_file_offset(string) +DEFINE_FETCH_file_offset(string_size) + +/* Fetch type information table */ +const struct fetch_type uprobes_fetch_type_table[] = { + /* Special types */ + [FETCH_TYPE_STRING] = __ASSIGN_FETCH_TYPE("string", string, string, + sizeof(u32), 1, "__data_loc char[]"), + [FETCH_TYPE_STRSIZE] = __ASSIGN_FETCH_TYPE("string_size", u32, + string_size, sizeof(u32), 0, "u32"), + /* Basic types */ + ASSIGN_FETCH_TYPE(u8, u8, 0), + ASSIGN_FETCH_TYPE(u16, u16, 0), + ASSIGN_FETCH_TYPE(u32, u32, 0), + ASSIGN_FETCH_TYPE(u64, u64, 0), + ASSIGN_FETCH_TYPE(s8, u8, 1), + ASSIGN_FETCH_TYPE(s16, u16, 1), + ASSIGN_FETCH_TYPE(s32, u32, 1), + ASSIGN_FETCH_TYPE(s64, u64, 1), + + ASSIGN_FETCH_TYPE_END +}; + static inline void init_trace_uprobe_filter(struct trace_uprobe_filter *filter) { rwlock_init(&filter->rwlock); @@ -114,13 +250,13 @@ alloc_trace_uprobe(const char *group, const char *event, int nargs, bool is_ret) if (!tu) return ERR_PTR(-ENOMEM); - tu->call.class = &tu->class; - tu->call.name = kstrdup(event, GFP_KERNEL); - if (!tu->call.name) + tu->tp.call.class = &tu->tp.class; + tu->tp.call.name = kstrdup(event, GFP_KERNEL); + if (!tu->tp.call.name) goto error; - tu->class.system = kstrdup(group, GFP_KERNEL); - if (!tu->class.system) + tu->tp.class.system = kstrdup(group, GFP_KERNEL); + if (!tu->tp.class.system) goto error; INIT_LIST_HEAD(&tu->list); @@ -128,11 +264,11 @@ alloc_trace_uprobe(const char *group, const char *event, int nargs, bool is_ret) if (is_ret) tu->consumer.ret_handler = uretprobe_dispatcher; init_trace_uprobe_filter(&tu->filter); - tu->call.flags |= TRACE_EVENT_FL_USE_CALL_FILTER; + tu->tp.call.flags |= TRACE_EVENT_FL_USE_CALL_FILTER; return tu; error: - kfree(tu->call.name); + kfree(tu->tp.call.name); kfree(tu); return ERR_PTR(-ENOMEM); @@ -142,12 +278,12 @@ static void free_trace_uprobe(struct trace_uprobe *tu) { int i; - for (i = 0; i < tu->nr_args; i++) - traceprobe_free_probe_arg(&tu->args[i]); + for (i = 0; i < tu->tp.nr_args; i++) + traceprobe_free_probe_arg(&tu->tp.args[i]); iput(tu->inode); - kfree(tu->call.class->system); - kfree(tu->call.name); + kfree(tu->tp.call.class->system); + kfree(tu->tp.call.name); kfree(tu->filename); kfree(tu); } @@ -157,8 +293,8 @@ static struct trace_uprobe *find_probe_event(const char *event, const char *grou struct trace_uprobe *tu; list_for_each_entry(tu, &uprobe_list, list) - if (strcmp(tu->call.name, event) == 0 && - strcmp(tu->call.class->system, group) == 0) + if (strcmp(tu->tp.call.name, event) == 0 && + strcmp(tu->tp.call.class->system, group) == 0) return tu; return NULL; @@ -181,16 +317,16 @@ static int unregister_trace_uprobe(struct trace_uprobe *tu) /* Register a trace_uprobe and probe_event */ static int register_trace_uprobe(struct trace_uprobe *tu) { - struct trace_uprobe *old_tp; + struct trace_uprobe *old_tu; int ret; mutex_lock(&uprobe_lock); /* register as an event */ - old_tp = find_probe_event(tu->call.name, tu->call.class->system); - if (old_tp) { + old_tu = find_probe_event(tu->tp.call.name, tu->tp.call.class->system); + if (old_tu) { /* delete old event */ - ret = unregister_trace_uprobe(old_tp); + ret = unregister_trace_uprobe(old_tu); if (ret) goto end; } @@ -211,7 +347,7 @@ end: /* * Argument syntax: - * - Add uprobe: p|r[:[GRP/]EVENT] PATH:SYMBOL [FETCHARGS] + * - Add uprobe: p|r[:[GRP/]EVENT] PATH:OFFSET [FETCHARGS] * * - Remove uprobe: -:[GRP/]EVENT */ @@ -360,34 +496,36 @@ static int create_trace_uprobe(int argc, char **argv) /* parse arguments */ ret = 0; for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) { + struct probe_arg *parg = &tu->tp.args[i]; + /* Increment count for freeing args in error case */ - tu->nr_args++; + tu->tp.nr_args++; /* Parse argument name */ arg = strchr(argv[i], '='); if (arg) { *arg++ = '\0'; - tu->args[i].name = kstrdup(argv[i], GFP_KERNEL); + parg->name = kstrdup(argv[i], GFP_KERNEL); } else { arg = argv[i]; /* If argument name is omitted, set "argN" */ snprintf(buf, MAX_EVENT_NAME_LEN, "arg%d", i + 1); - tu->args[i].name = kstrdup(buf, GFP_KERNEL); + parg->name = kstrdup(buf, GFP_KERNEL); } - if (!tu->args[i].name) { + if (!parg->name) { pr_info("Failed to allocate argument[%d] name.\n", i); ret = -ENOMEM; goto error; } - if (!is_good_name(tu->args[i].name)) { - pr_info("Invalid argument[%d] name: %s\n", i, tu->args[i].name); + if (!is_good_name(parg->name)) { + pr_info("Invalid argument[%d] name: %s\n", i, parg->name); ret = -EINVAL; goto error; } - if (traceprobe_conflict_field_name(tu->args[i].name, tu->args, i)) { + if (traceprobe_conflict_field_name(parg->name, tu->tp.args, i)) { pr_info("Argument[%d] name '%s' conflicts with " "another field.\n", i, argv[i]); ret = -EINVAL; @@ -395,7 +533,8 @@ static int create_trace_uprobe(int argc, char **argv) } /* Parse fetch argument */ - ret = traceprobe_parse_probe_arg(arg, &tu->size, &tu->args[i], false, false); + ret = traceprobe_parse_probe_arg(arg, &tu->tp.size, parg, + is_return, false); if (ret) { pr_info("Parse error at argument[%d]. (%d)\n", i, ret); goto error; @@ -459,11 +598,11 @@ static int probes_seq_show(struct seq_file *m, void *v) char c = is_ret_probe(tu) ? 'r' : 'p'; int i; - seq_printf(m, "%c:%s/%s", c, tu->call.class->system, tu->call.name); + seq_printf(m, "%c:%s/%s", c, tu->tp.call.class->system, tu->tp.call.name); seq_printf(m, " %s:0x%p", tu->filename, (void *)tu->offset); - for (i = 0; i < tu->nr_args; i++) - seq_printf(m, " %s=%s", tu->args[i].name, tu->args[i].comm); + for (i = 0; i < tu->tp.nr_args; i++) + seq_printf(m, " %s=%s", tu->tp.args[i].name, tu->tp.args[i].comm); seq_printf(m, "\n"); return 0; @@ -509,7 +648,7 @@ static int probes_profile_seq_show(struct seq_file *m, void *v) { struct trace_uprobe *tu = v; - seq_printf(m, " %s %-44s %15lu\n", tu->filename, tu->call.name, tu->nhit); + seq_printf(m, " %s %-44s %15lu\n", tu->filename, tu->tp.call.name, tu->nhit); return 0; } @@ -533,21 +672,117 @@ static const struct file_operations uprobe_profile_ops = { .release = seq_release, }; +struct uprobe_cpu_buffer { + struct mutex mutex; + void *buf; +}; +static struct uprobe_cpu_buffer __percpu *uprobe_cpu_buffer; +static int uprobe_buffer_refcnt; + +static int uprobe_buffer_init(void) +{ + int cpu, err_cpu; + + uprobe_cpu_buffer = alloc_percpu(struct uprobe_cpu_buffer); + if (uprobe_cpu_buffer == NULL) + return -ENOMEM; + + for_each_possible_cpu(cpu) { + struct page *p = alloc_pages_node(cpu_to_node(cpu), + GFP_KERNEL, 0); + if (p == NULL) { + err_cpu = cpu; + goto err; + } + per_cpu_ptr(uprobe_cpu_buffer, cpu)->buf = page_address(p); + mutex_init(&per_cpu_ptr(uprobe_cpu_buffer, cpu)->mutex); + } + + return 0; + +err: + for_each_possible_cpu(cpu) { + if (cpu == err_cpu) + break; + free_page((unsigned long)per_cpu_ptr(uprobe_cpu_buffer, cpu)->buf); + } + + free_percpu(uprobe_cpu_buffer); + return -ENOMEM; +} + +static int uprobe_buffer_enable(void) +{ + int ret = 0; + + BUG_ON(!mutex_is_locked(&event_mutex)); + + if (uprobe_buffer_refcnt++ == 0) { + ret = uprobe_buffer_init(); + if (ret < 0) + uprobe_buffer_refcnt--; + } + + return ret; +} + +static void uprobe_buffer_disable(void) +{ + BUG_ON(!mutex_is_locked(&event_mutex)); + + if (--uprobe_buffer_refcnt == 0) { + free_percpu(uprobe_cpu_buffer); + uprobe_cpu_buffer = NULL; + } +} + +static struct uprobe_cpu_buffer *uprobe_buffer_get(void) +{ + struct uprobe_cpu_buffer *ucb; + int cpu; + + cpu = raw_smp_processor_id(); + ucb = per_cpu_ptr(uprobe_cpu_buffer, cpu); + + /* + * Use per-cpu buffers for fastest access, but we might migrate + * so the mutex makes sure we have sole access to it. + */ + mutex_lock(&ucb->mutex); + + return ucb; +} + +static void uprobe_buffer_put(struct uprobe_cpu_buffer *ucb) +{ + mutex_unlock(&ucb->mutex); +} + static void uprobe_trace_print(struct trace_uprobe *tu, unsigned long func, struct pt_regs *regs) { struct uprobe_trace_entry_head *entry; struct ring_buffer_event *event; struct ring_buffer *buffer; + struct uprobe_cpu_buffer *ucb; void *data; - int size, i; - struct ftrace_event_call *call = &tu->call; + int size, dsize, esize; + struct ftrace_event_call *call = &tu->tp.call; + + dsize = __get_data_size(&tu->tp, regs); + esize = SIZEOF_TRACE_ENTRY(is_ret_probe(tu)); - size = SIZEOF_TRACE_ENTRY(is_ret_probe(tu)); + if (WARN_ON_ONCE(!uprobe_cpu_buffer || tu->tp.size + dsize > PAGE_SIZE)) + return; + + ucb = uprobe_buffer_get(); + store_trace_args(esize, &tu->tp, regs, ucb->buf, dsize); + + size = esize + tu->tp.size + dsize; event = trace_current_buffer_lock_reserve(&buffer, call->event.type, - size + tu->size, 0, 0); + size, 0, 0); if (!event) - return; + goto out; entry = ring_buffer_event_data(event); if (is_ret_probe(tu)) { @@ -559,11 +794,13 @@ static void uprobe_trace_print(struct trace_uprobe *tu, data = DATAOF_TRACE_ENTRY(entry, false); } - for (i = 0; i < tu->nr_args; i++) - call_fetch(&tu->args[i].fetch, regs, data + tu->args[i].offset); + memcpy(data, ucb->buf, tu->tp.size + dsize); if (!call_filter_check_discard(call, entry, buffer, event)) trace_buffer_unlock_commit(buffer, event, 0, 0); + +out: + uprobe_buffer_put(ucb); } /* uprobe handler */ @@ -591,23 +828,24 @@ print_uprobe_event(struct trace_iterator *iter, int flags, struct trace_event *e int i; entry = (struct uprobe_trace_entry_head *)iter->ent; - tu = container_of(event, struct trace_uprobe, call.event); + tu = container_of(event, struct trace_uprobe, tp.call.event); if (is_ret_probe(tu)) { - if (!trace_seq_printf(s, "%s: (0x%lx <- 0x%lx)", tu->call.name, + if (!trace_seq_printf(s, "%s: (0x%lx <- 0x%lx)", tu->tp.call.name, entry->vaddr[1], entry->vaddr[0])) goto partial; data = DATAOF_TRACE_ENTRY(entry, true); } else { - if (!trace_seq_printf(s, "%s: (0x%lx)", tu->call.name, + if (!trace_seq_printf(s, "%s: (0x%lx)", tu->tp.call.name, entry->vaddr[0])) goto partial; data = DATAOF_TRACE_ENTRY(entry, false); } - for (i = 0; i < tu->nr_args; i++) { - if (!tu->args[i].type->print(s, tu->args[i].name, - data + tu->args[i].offset, entry)) + for (i = 0; i < tu->tp.nr_args; i++) { + struct probe_arg *parg = &tu->tp.args[i]; + + if (!parg->type->print(s, parg->name, data + parg->offset, entry)) goto partial; } @@ -618,11 +856,6 @@ partial: return TRACE_TYPE_PARTIAL_LINE; } -static inline bool is_trace_uprobe_enabled(struct trace_uprobe *tu) -{ - return tu->flags & (TP_FLAG_TRACE | TP_FLAG_PROFILE); -} - typedef bool (*filter_func_t)(struct uprobe_consumer *self, enum uprobe_filter_ctx ctx, struct mm_struct *mm); @@ -632,29 +865,35 @@ probe_event_enable(struct trace_uprobe *tu, int flag, filter_func_t filter) { int ret = 0; - if (is_trace_uprobe_enabled(tu)) + if (trace_probe_is_enabled(&tu->tp)) return -EINTR; + ret = uprobe_buffer_enable(); + if (ret < 0) + return ret; + WARN_ON(!uprobe_filter_is_empty(&tu->filter)); - tu->flags |= flag; + tu->tp.flags |= flag; tu->consumer.filter = filter; ret = uprobe_register(tu->inode, tu->offset, &tu->consumer); if (ret) - tu->flags &= ~flag; + tu->tp.flags &= ~flag; return ret; } static void probe_event_disable(struct trace_uprobe *tu, int flag) { - if (!is_trace_uprobe_enabled(tu)) + if (!trace_probe_is_enabled(&tu->tp)) return; WARN_ON(!uprobe_filter_is_empty(&tu->filter)); uprobe_unregister(tu->inode, tu->offset, &tu->consumer); - tu->flags &= ~flag; + tu->tp.flags &= ~flag; + + uprobe_buffer_disable(); } static int uprobe_event_define_fields(struct ftrace_event_call *event_call) @@ -672,12 +911,12 @@ static int uprobe_event_define_fields(struct ftrace_event_call *event_call) size = SIZEOF_TRACE_ENTRY(false); } /* Set argument names as fields */ - for (i = 0; i < tu->nr_args; i++) { - ret = trace_define_field(event_call, tu->args[i].type->fmttype, - tu->args[i].name, - size + tu->args[i].offset, - tu->args[i].type->size, - tu->args[i].type->is_signed, + for (i = 0; i < tu->tp.nr_args; i++) { + struct probe_arg *parg = &tu->tp.args[i]; + + ret = trace_define_field(event_call, parg->type->fmttype, + parg->name, size + parg->offset, + parg->type->size, parg->type->is_signed, FILTER_OTHER); if (ret) @@ -686,59 +925,6 @@ static int uprobe_event_define_fields(struct ftrace_event_call *event_call) return 0; } -#define LEN_OR_ZERO (len ? len - pos : 0) -static int __set_print_fmt(struct trace_uprobe *tu, char *buf, int len) -{ - const char *fmt, *arg; - int i; - int pos = 0; - - if (is_ret_probe(tu)) { - fmt = "(%lx <- %lx)"; - arg = "REC->" FIELD_STRING_FUNC ", REC->" FIELD_STRING_RETIP; - } else { - fmt = "(%lx)"; - arg = "REC->" FIELD_STRING_IP; - } - - /* When len=0, we just calculate the needed length */ - - pos += snprintf(buf + pos, LEN_OR_ZERO, "\"%s", fmt); - - for (i = 0; i < tu->nr_args; i++) { - pos += snprintf(buf + pos, LEN_OR_ZERO, " %s=%s", - tu->args[i].name, tu->args[i].type->fmt); - } - - pos += snprintf(buf + pos, LEN_OR_ZERO, "\", %s", arg); - - for (i = 0; i < tu->nr_args; i++) { - pos += snprintf(buf + pos, LEN_OR_ZERO, ", REC->%s", - tu->args[i].name); - } - - return pos; /* return the length of print_fmt */ -} -#undef LEN_OR_ZERO - -static int set_print_fmt(struct trace_uprobe *tu) -{ - char *print_fmt; - int len; - - /* First: called with 0 length to calculate the needed length */ - len = __set_print_fmt(tu, NULL, 0); - print_fmt = kmalloc(len + 1, GFP_KERNEL); - if (!print_fmt) - return -ENOMEM; - - /* Second: actually write the @print_fmt */ - __set_print_fmt(tu, print_fmt, len + 1); - tu->call.print_fmt = print_fmt; - - return 0; -} - #ifdef CONFIG_PERF_EVENTS static bool __uprobe_perf_filter(struct trace_uprobe_filter *filter, struct mm_struct *mm) @@ -831,14 +1017,27 @@ static bool uprobe_perf_filter(struct uprobe_consumer *uc, static void uprobe_perf_print(struct trace_uprobe *tu, unsigned long func, struct pt_regs *regs) { - struct ftrace_event_call *call = &tu->call; + struct ftrace_event_call *call = &tu->tp.call; struct uprobe_trace_entry_head *entry; struct hlist_head *head; + struct uprobe_cpu_buffer *ucb; void *data; - int size, rctx, i; + int size, dsize, esize; + int rctx; - size = SIZEOF_TRACE_ENTRY(is_ret_probe(tu)); - size = ALIGN(size + tu->size + sizeof(u32), sizeof(u64)) - sizeof(u32); + dsize = __get_data_size(&tu->tp, regs); + esize = SIZEOF_TRACE_ENTRY(is_ret_probe(tu)); + + if (WARN_ON_ONCE(!uprobe_cpu_buffer)) + return; + + size = esize + tu->tp.size + dsize; + size = ALIGN(size + sizeof(u32), sizeof(u64)) - sizeof(u32); + if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE, "profile buffer not large enough")) + return; + + ucb = uprobe_buffer_get(); + store_trace_args(esize, &tu->tp, regs, ucb->buf, dsize); preempt_disable(); head = this_cpu_ptr(call->perf_events); @@ -858,12 +1057,18 @@ static void uprobe_perf_print(struct trace_uprobe *tu, data = DATAOF_TRACE_ENTRY(entry, false); } - for (i = 0; i < tu->nr_args; i++) - call_fetch(&tu->args[i].fetch, regs, data + tu->args[i].offset); + memcpy(data, ucb->buf, tu->tp.size + dsize); + + if (size - esize > tu->tp.size + dsize) { + int len = tu->tp.size + dsize; + + memset(data + len, 0, size - esize - len); + } perf_trace_buf_submit(entry, size, rctx, 0, 1, regs, head, NULL); out: preempt_enable(); + uprobe_buffer_put(ucb); } /* uprobe profile handler */ @@ -921,16 +1126,22 @@ int trace_uprobe_register(struct ftrace_event_call *event, enum trace_reg type, static int uprobe_dispatcher(struct uprobe_consumer *con, struct pt_regs *regs) { struct trace_uprobe *tu; + struct uprobe_dispatch_data udd; int ret = 0; tu = container_of(con, struct trace_uprobe, consumer); tu->nhit++; - if (tu->flags & TP_FLAG_TRACE) + udd.tu = tu; + udd.bp_addr = instruction_pointer(regs); + + current->utask->vaddr = (unsigned long) &udd; + + if (tu->tp.flags & TP_FLAG_TRACE) ret |= uprobe_trace_func(tu, regs); #ifdef CONFIG_PERF_EVENTS - if (tu->flags & TP_FLAG_PROFILE) + if (tu->tp.flags & TP_FLAG_PROFILE) ret |= uprobe_perf_func(tu, regs); #endif return ret; @@ -940,14 +1151,20 @@ static int uretprobe_dispatcher(struct uprobe_consumer *con, unsigned long func, struct pt_regs *regs) { struct trace_uprobe *tu; + struct uprobe_dispatch_data udd; tu = container_of(con, struct trace_uprobe, consumer); - if (tu->flags & TP_FLAG_TRACE) + udd.tu = tu; + udd.bp_addr = func; + + current->utask->vaddr = (unsigned long) &udd; + + if (tu->tp.flags & TP_FLAG_TRACE) uretprobe_trace_func(tu, func, regs); #ifdef CONFIG_PERF_EVENTS - if (tu->flags & TP_FLAG_PROFILE) + if (tu->tp.flags & TP_FLAG_PROFILE) uretprobe_perf_func(tu, func, regs); #endif return 0; @@ -959,7 +1176,7 @@ static struct trace_event_functions uprobe_funcs = { static int register_uprobe_event(struct trace_uprobe *tu) { - struct ftrace_event_call *call = &tu->call; + struct ftrace_event_call *call = &tu->tp.call; int ret; /* Initialize ftrace_event_call */ @@ -967,7 +1184,7 @@ static int register_uprobe_event(struct trace_uprobe *tu) call->event.funcs = &uprobe_funcs; call->class->define_fields = uprobe_event_define_fields; - if (set_print_fmt(tu) < 0) + if (set_print_fmt(&tu->tp, is_ret_probe(tu)) < 0) return -ENOMEM; ret = register_ftrace_event(&call->event); @@ -994,11 +1211,11 @@ static int unregister_uprobe_event(struct trace_uprobe *tu) int ret; /* tu->event is unregistered in trace_remove_event_call() */ - ret = trace_remove_event_call(&tu->call); + ret = trace_remove_event_call(&tu->tp.call); if (ret) return ret; - kfree(tu->call.print_fmt); - tu->call.print_fmt = NULL; + kfree(tu->tp.call.print_fmt); + tu->tp.call.print_fmt = NULL; return 0; } |
