/* SPDX-License-Identifier: GPL-2.0 */ #ifndef _LINUX_KERNEL_TRACE_H #define _LINUX_KERNEL_TRACE_H #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef CONFIG_FTRACE_SYSCALLS #include /* For NR_SYSCALLS */ #include /* some archs define it here */ #endif enum trace_type { __TRACE_FIRST_TYPE = 0, TRACE_FN, TRACE_CTX, TRACE_WAKE, TRACE_STACK, TRACE_PRINT, TRACE_BPRINT, TRACE_MMIO_RW, TRACE_MMIO_MAP, TRACE_BRANCH, TRACE_GRAPH_RET, TRACE_GRAPH_ENT, TRACE_USER_STACK, TRACE_BLK, TRACE_BPUTS, TRACE_HWLAT, TRACE_RAW_DATA, __TRACE_LAST_TYPE, }; #undef __field #define __field(type, item) type item; #undef __field_struct #define __field_struct(type, item) __field(type, item) #undef __field_desc #define __field_desc(type, container, item) #undef __array #define __array(type, item, size) type item[size]; #undef __array_desc #define __array_desc(type, container, item, size) #undef __dynamic_array #define __dynamic_array(type, item) type item[]; #undef F_STRUCT #define F_STRUCT(args...) args #undef FTRACE_ENTRY #define FTRACE_ENTRY(name, struct_name, id, tstruct, print, filter) \ struct struct_name { \ struct trace_entry ent; \ tstruct \ } #undef FTRACE_ENTRY_DUP #define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk, filter) #undef FTRACE_ENTRY_REG #define FTRACE_ENTRY_REG(name, struct_name, id, tstruct, print, \ filter, regfn) \ FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print), \ filter) #undef FTRACE_ENTRY_PACKED #define FTRACE_ENTRY_PACKED(name, struct_name, id, tstruct, print, \ filter) \ FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print), \ filter) __packed #include "trace_entries.h" /* * syscalls are special, and need special handling, this is why * they are not included in trace_entries.h */ struct syscall_trace_enter { struct trace_entry ent; int nr; unsigned long args[]; }; struct syscall_trace_exit { struct trace_entry ent; int nr; long ret; }; struct kprobe_trace_entry_head { struct trace_entry ent; unsigned long ip; }; struct kretprobe_trace_entry_head { struct trace_entry ent; unsigned long func; unsigned long ret_ip; }; /* * trace_flag_type is an enumeration that holds different * states when a trace occurs. These are: * IRQS_OFF - interrupts were disabled * IRQS_NOSUPPORT - arch does not support irqs_disabled_flags * NEED_RESCHED - reschedule is requested * HARDIRQ - inside an interrupt handler * SOFTIRQ - inside a softirq handler */ enum trace_flag_type { TRACE_FLAG_IRQS_OFF = 0x01, TRACE_FLAG_IRQS_NOSUPPORT = 0x02, TRACE_FLAG_NEED_RESCHED = 0x04, TRACE_FLAG_HARDIRQ = 0x08, TRACE_FLAG_SOFTIRQ = 0x10, TRACE_FLAG_PREEMPT_RESCHED = 0x20, TRACE_FLAG_NMI = 0x40, }; #define TRACE_BUF_SIZE 1024 struct trace_array; /* * The CPU trace array - it consists of thousands of trace entries * plus some other descriptor data: (for example which task started * the trace, etc.) */ struct trace_array_cpu { atomic_t disabled; void *buffer_page; /* ring buffer spare */ unsigned long entries; unsigned long saved_latency; unsigned long critical_start; unsigned long critical_end; unsigned long critical_sequence; unsigned long nice; unsigned long policy; unsigned long rt_priority; unsigned long skipped_entries; u64 preempt_timestamp; pid_t pid; kuid_t uid; char comm[TASK_COMM_LEN]; bool ignore_pid; #ifdef CONFIG_FUNCTION_TRACER bool ftrace_ignore_pid; #endif }; struct tracer; struct trace_option_dentry; struct trace_buffer { struct trace_array *tr; struct ring_buffer *buffer; struct trace_array_cpu __percpu *data; u64 time_start; int cpu; }; #define TRACE_FLAGS_MAX_SIZE 32 struct trace_options { struct tracer *tracer; struct trace_option_dentry *topts; }; struct trace_pid_list { int pid_max; unsigned long *pids; }; /* * The trace array - an array of per-CPU trace arrays. This is the * highest level data structure that individual tracers deal with. * They have on/off state as well: */ struct trace_array { struct list_head list; char *name; struct trace_buffer trace_buffer; #ifdef CONFIG_TRACER_MAX_TRACE /* * The max_buffer is used to snapshot the trace when a maximum * latency is reached, or when the user initiates a snapshot. * Some tracers will use this to store a maximum trace while * it continues examining live traces. * * The buffers for the max_buffer are set up the same as the trace_buffer * When a snapshot is taken, the buffer of the max_buffer is swapped * with the buffer of the trace_buffer and the buffers are reset for * the trace_buffer so the tracing can continue. */ struct trace_buffer max_buffer; bool allocated_snapshot; #endif #if defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER) unsigned long max_latency; #endif struct trace_pid_list __rcu *filtered_pids; /* * max_lock is used to protect the swapping of buffers * when taking a max snapshot. The buffers themselves are * protected by per_cpu spinlocks. But the action of the swap * needs its own lock. * * This is defined as a arch_spinlock_t in order to help * with performance when lockdep debugging is enabled. * * It is also used in other places outside the update_max_tr * so it needs to be defined outside of the * CONFIG_TRACER_MAX_TRACE. */ arch_spinlock_t max_lock; int buffer_disabled; #ifdef CONFIG_FTRACE_SYSCALLS int sys_refcount_enter; int sys_refcount_exit; struct trace_event_file __rcu *enter_syscall_files[NR_syscalls]; struct trace_event_file __rcu *exit_syscall_files[NR_syscalls]; #endif int stop_count; int clock_id; int nr_topts; bool clear_trace; struct tracer *current_trace; unsigned int trace_flags; unsigned char trace_flags_index[TRACE_FLAGS_MAX_SIZE]; unsigned int flags; raw_spinlock_t start_lock; struct dentry *dir; struct dentry *options; struct dentry *percpu_dir; struct dentry *event_dir; struct trace_options *topts; struct list_head systems; struct list_head events; cpumask_var_t tracing_cpumask; /* only trace on set CPUs */ int ref; #ifdef CONFIG_FUNCTION_TRACER struct ftrace_ops *ops; struct trace_pid_list __rcu *function_pids; #ifdef CONFIG_DYNAMIC_FTRACE /* All of these are protected by the ftrace_lock */ struct list_head func_probes; struct list_head mod_trace; struct list_head mod_notrace; #endif /* function tracing enabled */ int function_enabled; #endif int time_stamp_abs_ref; struct list_head hist_vars; }; enum { TRACE_ARRAY_FL_GLOBAL = (1 << 0) }; extern struct list_head ftrace_trace_arrays; extern struct mutex trace_types_lock; extern int trace_array_get(struct trace_array *tr); extern void trace_array_put(struct trace_array *tr); extern int tracing_set_time_stamp_abs(struct trace_array *tr, bool abs); extern int tracing_set_clock(struct trace_array *tr, const char *clockstr); extern bool trace_clock_in_ns(struct trace_array *tr); /* * The global tracer (top) should be the first trace array added, * but we check the flag anyway. */ static inline struct trace_array *top_trace_array(void) { struct trace_array *tr; if (list_empty(&ftrace_trace_arrays)) return NULL; tr = list_entry(ftrace_trace_arrays.prev, typeof(*tr), list); WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL)); return tr; } #define FTRACE_CMP_TYPE(var, type) \ __builtin_types_compatible_p(typeof(var), type *) #undef IF_ASSIGN #define IF_ASSIGN(var, entry, etype, id) \ if (FTRACE_CMP_TYPE(var, etype)) { \ var = (typeof(var))(entry); \ WARN_ON(id && (entry)->type != id); \ break; \ } /* Will cause compile errors if type is not found. */ extern void __ftrace_bad_type(void); /* * The trace_assign_type is a verifier that the entry type is * the same as the type being assigned. To add new types simply * add a line with the following format: * * IF_ASSIGN(var, ent, type, id); * * Where "type" is the trace type that includes the trace_entry * as the "ent" item. And "id" is the trace identifier that is * used in the trace_type enum. * * If the type can have more than one id, then use zero. */ #define trace_assign_type(var, ent) \ do { \ IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN); \ IF_ASSIGN(var, ent, struct ctx_switch_entry, 0); \ IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK); \ IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\ IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT); \ IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT); \ IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS); \ IF_ASSIGN(var, ent, struct hwlat_entry, TRACE_HWLAT); \ IF_ASSIGN(var, ent, struct raw_data_entry, TRACE_RAW_DATA);\ IF_ASSIGN(var, ent, struct trace_mmiotrace_rw, \ TRACE_MMIO_RW); \ IF_ASSIGN(var, ent, struct trace_mmiotrace_map, \ TRACE_MMIO_MAP); \ IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \ IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry, \ TRACE_GRAPH_ENT); \ IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry, \ TRACE_GRAPH_RET); \ __ftrace_bad_type(); \ } while (0) /* * An option specific to a tracer. This is a boolean value. * The bit is the bit index that sets its value on the * flags value in struct tracer_flags. */ struct tracer_opt { const char *name; /* Will appear on the trace_options file */ u32 bit; /* Mask assigned in val field in tracer_flags */ }; /* * The set of specific options for a tracer. Your tracer * have to set the initial value of the flags val. */ struct tracer_flags { u32 val; struct tracer_opt *opts; struct tracer *trace; }; /* Makes more easy to define a tracer opt */ #define TRACER_OPT(s, b) .name = #s, .bit = b struct trace_option_dentry { struct tracer_opt *opt; struct tracer_flags *flags; struct trace_array *tr; struct dentry *entry; }; /** * struct tracer - a specific tracer and its callbacks to interact with tracefs * @name: the name chosen to select it on the available_tracers file * @init: called when one switches to this tracer (echo name > current_tracer) * @reset: called when one switches to another tracer * @start: called when tracing is unpaused (echo 1 > tracing_on) * @stop: called when tracing is paused (echo 0 > tracing_on) * @update_thresh: called when tracing_thresh is updated * @open: called when the trace file is opened * @pipe_open: called when the trace_pipe file is opened * @close: called when the trace file is released * @pipe_close: called when the trace_pipe file is released * @read: override the default read callback on trace_pipe * @splice_read: override the default splice_read callback on trace_pipe * @selftest: selftest to run on boot (see trace_selftest.c) * @print_headers: override the first lines that describe your columns * @print_line: callback that prints a trace * @set_flag: signals one of your private flags changed (trace_options file) * @flags: your private flags */ struct tracer { const char *name; int (*init)(struct trace_array *tr); void (*reset)(struct trace_array *tr); void (*start)(struct trace_array *tr); void (*stop)(struct trace_array *tr); int (*update_thresh)(struct trace_array *tr); void (*open)(struct trace_iterator *iter); void (*pipe_open)(struct trace_iterator *iter); void (*close)(struct trace_iterator *iter); void (*pipe_close)(struct trace_iterator *iter); ssize_t (*read)(struct trace_iterator *iter, struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos); ssize_t (*splice_read)(struct trace_iterator *iter, struct file *filp, loff_t *ppos, struct pipe_inode_info *pipe, size_t len, unsigned int flags); #ifdef CONFIG_FTRACE_STARTUP_TEST int (*selftest)(struct tracer *trace, struct trace_array *tr); #endif void (*print_header)(struct seq_file *m); enum print_line_t (*print_line)(struct trace_iterator *iter); /* If you handled the flag setting, return 0 */ int (*set_flag)(struct trace_array *tr, u32 old_flags, u32 bit, int set); /* Return 0 if OK with change, else return non-zero */ int (*flag_changed)(struct trace_array *tr, u32 mask, int set); struct tracer *next; struct tracer_flags *flags; int enabled; int ref; bool print_max; bool allow_instances; #ifdef CONFIG_TRACER_MAX_TRACE bool use_max_tr; #endif /* True if tracer cannot be enabled in kernel param */ bool noboot; }; /* Only current can touch trace_recursion */ /* * For function tracing recursion: * The order of these bits are important. * * When function tracing occurs, the following steps are made: * If arch does not support a ftrace feature: * call internal function (uses INTERNAL bits) which calls... * If callback is registered to the "global" list, the list * function is called and recursion checks the GLOBAL bits. * then this function calls... * The function callback, which can use the FTRACE bits to * check for recursion. * * Now if the arch does not suppport a feature, and it calls * the global list function which calls the ftrace callback * all three of these steps will do a recursion protection. * There's no reason to do one if the previous caller already * did. The recursion that we are protecting against will * go through the same steps again. * * To prevent the multiple recursion checks, if a recursion * bit is set that is higher than the MAX bit of the current * check, then we know that the check was made by the previous * caller, and we can skip the current check. */ enum { TRACE_BUFFER_BIT, TRACE_BUFFER_NMI_BIT, TRACE_BUFFER_IRQ_BIT, TRACE_BUFFER_SIRQ_BIT, /* Start of function recursion bits */ TRACE_FTRACE_BIT, TRACE_FTRACE_NMI_BIT, TRACE_FTRACE_IRQ_BIT, TRACE_FTRACE_SIRQ_BIT, /* INTERNAL_BITs must be greater than FTRACE_BITs */ TRACE_INTERNAL_BIT, TRACE_INTERNAL_NMI_BIT, TRACE_INTERNAL_IRQ_BIT, TRACE_INTERNAL_SIRQ_BIT, TRACE_BRANCH_BIT, /* * Abuse of the trace_recursion. * As we need a way to maintain state if we are tracing the function * graph in irq because we want to trace a particular function that * was called in irq context but we have irq tracing off. Since this * can only be modified by current, we can reuse trace_recursion. */ TRACE_IRQ_BIT, }; #define trace_recursion_set(bit) do { (current)->trace_recursion |= (1<<(bit)); } while (0) #define trace_recursion_clear(bit) do { (current)->trace_recursion &= ~(1<<(bit)); } while (0) #define trace_recursion_test(bit) ((current)->trace_recursion & (1<<(bit))) #define TRACE_CONTEXT_BITS 4 #define TRACE_FTRACE_START TRACE_FTRACE_BIT #define TRACE_FTRACE_MAX ((1 << (TRACE_FTRACE_START + TRACE_CONTEXT_BITS)) - 1) #define TRACE_LIST_START TRACE_INTERNAL_BIT #define TRACE_LIST_MAX ((1 << (TRACE_LIST_START + TRACE_CONTEXT_BITS)) - 1) #define TRACE_CONTEXT_MASK TRACE_LIST_MAX static __always_inline int trace_get_context_bit(void) { int bit; if (in_interrupt()) { if (in_nmi()) bit = 0; else if (in_irq()) bit = 1; else bit = 2; } else bit = 3; return bit; } static __always_inline int trace_test_and_set_recursion(int start, int max) { unsigned int val = current->trace_recursion; int bit; /* A previous recursion check was made */ if ((val & TRACE_CONTEXT_MASK) > max) return 0; bit = trace_get_context_bit() + start; if (unlikely(val & (1 << bit))) return -1; val |= 1 << bit; current->trace_recursion = val; barrier(); return bit; } static __always_inline void trace_clear_recursion(int bit) { unsigned int val = current->trace_recursion; if (!bit) return; bit = 1 << bit; val &= ~bit; barrier(); current->trace_recursion = val; } static inline struct ring_buffer_iter * trace_buffer_iter(struct trace_iterator *iter, int cpu) { if (iter->buffer_iter && iter->buffer_iter[cpu]) return iter->buffer_iter[cpu]; return NULL; } int tracer_init(struct tracer *t, struct trace_array *tr); int tracing_is_enabled(void); void tracing_reset(struct trace_buffer *buf, int cpu); void tracing_reset_online_cpus(struct trace_buffer *buf); void tracing_reset_current(int cpu); void tracing_reset_all_online_cpus(void); int tracing_open_generic(struct inode *inode, struct file *filp); bool tracing_is_disabled(void); int tracer_tracing_is_on(struct trace_array *tr); void tracer_tracing_on(struct trace_array *tr); void tracer_tracing_off(struct trace_array *tr); struct dentry *trace_create_file(const char *name, umode_t mode, struct dentry *parent, void *data, const struct file_operations *fops); struct dentry *tracing_init_dentry(void); struct ring_buffer_event; struct ring_buffer_event * trace_buffer_lock_reserve(struct ring_buffer *buffer, int type, unsigned long len, unsigned long flags, int pc); struct trace_entry *tracing_get_trace_entry(struct trace_array *tr, struct trace_array_cpu *data); struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, int *ent_cpu, u64 *ent_ts); void trace_buffer_unlock_commit_nostack(struct ring_buffer *buffer, struct ring_buffer_event *event); int trace_empty(struct trace_iterator *iter); void *trace_find_next_entry_inc(struct trace_iterator *iter); void trace_init_global_iter(struct trace_iterator *iter); void tracing_iter_reset(struct trace_iterator *iter, int cpu); void trace_function(struct trace_array *tr, unsigned long ip, unsigned long parent_ip, unsigned long flags, int pc); void trace_graph_function(struct trace_array *tr, unsigned long ip, unsigned long parent_ip, unsigned long flags, int pc); void trace_latency_header(struct seq_file *m); void trace_default_header(struct seq_file *m); void print_trace_header(struct seq_file *m, struct trace_iterator *iter); int trace_empty(struct trace_iterator *iter); void trace_graph_return(struct ftrace_graph_ret *trace); int trace_graph_entry(struct ftrace_graph_ent *trace); void set_graph_array(struct trace_array *tr); void tracing_start_cmdline_record(void); void tracing_stop_cmdline_record(void); void tracing_start_tgid_record(void); void tracing_stop_tgid_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) \ for_each_cpu(cpu, tracing_buffer_mask) extern unsigned long nsecs_to_usecs(unsigned long nsecs); extern unsigned long tracing_thresh; /* PID filtering */ extern int pid_max; bool trace_find_filtered_pid(struct trace_pid_list *filtered_pids, pid_t search_pid); bool trace_ignore_this_task(struct trace_pid_list *filtered_pids, struct task_struct *task); void trace_filter_add_remove_task(struct trace_pid_list *pid_list, struct task_struct *self, struct task_struct *task); void *trace_pid_next(struct trace_pid_list *pid_list, void *v, loff_t *pos); void *trace_pid_start(struct trace_pid_list *pid_list, loff_t *pos); int trace_pid_show(struct seq_file *m, void *v); void trace_free_pid_list(struct trace_pid_list *pid_list); int trace_pid_write(struct trace_pid_list *filtered_pids, struct trace_pid_list **new_pid_list, const char __user *ubuf, size_t cnt); #ifdef CONFIG_TRACER_MAX_TRACE void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu); void update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu); #endif /* CONFIG_TRACER_MAX_TRACE */ #ifdef CONFIG_STACKTRACE void ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc); void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, int pc); #else static inline void ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc) { } static inline void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, int pc) { } #endif /* CONFIG_STACKTRACE */ extern u64 ftrace_now(int cpu); extern void trace_find_cmdline(int pid, char comm[]); extern int trace_find_tgid(int pid); extern void trace_event_follow_fork(struct trace_array *tr, bool enable); #ifdef CONFIG_DYNAMIC_FTRACE extern unsigned long ftrace_update_tot_cnt; void ftrace_init_trace_array(struct trace_array *tr); #else static inline void ftrace_init_trace_array(struct trace_array *tr) { } #endif #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func extern int DYN_FTRACE_TEST_NAME(void); #define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2 extern int DYN_FTRACE_TEST_NAME2(void); extern bool ring_buffer_expanded; extern bool tracing_selftest_disabled; #ifdef CONFIG_FTRACE_STARTUP_TEST extern int trace_selftest_startup_function(struct tracer *trace, struct trace_array *tr); extern int trace_selftest_startup_function_graph(struct tracer *trace, struct trace_array *tr); extern int trace_selftest_startup_irqsoff(struct tracer *trace, struct trace_array *tr); extern int trace_selftest_startup_preemptoff(struct tracer *trace, struct trace_array *tr); extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace, struct trace_array *tr); extern int trace_selftest_startup_wakeup(struct tracer *trace, struct trace_array *tr); extern int trace_selftest_startup_nop(struct tracer *trace, struct trace_array *tr); extern int trace_selftest_startup_branch(struct tracer *trace, struct trace_array *tr); /* * Tracer data references selftest functions that only occur * on boot up. These can be __init functions. Thus, when selftests * are enabled, then the tracers need to reference __init functions. */ #define __tracer_data __refdata #else /* Tracers are seldom changed. Optimize when selftests are disabled. */ #define __tracer_data __read_mostly #endif /* CONFIG_FTRACE_STARTUP_TEST */ extern void *head_page(struct trace_array_cpu *data); extern unsigned long long ns2usecs(u64 nsec); extern int trace_vbprintk(unsigned long ip, const char *fmt, va_list args); extern int trace_vprintk(unsigned long ip, const char *fmt, va_list args); extern int trace_array_vprintk(struct trace_array *tr, unsigned long ip, const char *fmt, va_list args); int trace_array_printk(struct trace_array *tr, unsigned long ip, const char *fmt, ...); int trace_array_printk_buf(struct ring_buffer *buffer, unsigned long ip, const char *fmt, ...); void trace_printk_seq(struct trace_seq *s); enum print_line_t print_trace_line(struct trace_iterator *iter); extern char trace_find_mark(unsigned long long duration); struct ftrace_hash; struct ftrace_mod_load { struct list_head list; char *func; char *module; int enable; }; enum { FTRACE_HASH_FL_MOD = (1 << 0), }; struct ftrace_hash { unsigned long size_bits; struct hlist_head *buckets; unsigned long count; unsigned long flags; struct rcu_head rcu; }; struct ftrace_func_entry * ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip); static __always_inline bool ftrace_hash_empty(struct ftrace_hash *hash) { return !hash || !(hash->count || (hash->flags & FTRACE_HASH_FL_MOD)); } /* Standard output formatting function used for function return traces */ #ifdef CONFIG_FUNCTION_GRAPH_TRACER /* Flag options */ #define TRACE_GRAPH_PRINT_OVERRUN 0x1 #define TRACE_GRAPH_PRINT_CPU 0x2 #define TRACE_GRAPH_PRINT_OVERHEAD 0x4 #define TRACE_GRAPH_PRINT_PROC 0x8 #define TRACE_GRAPH_PRINT_DURATION 0x10 #define TRACE_GRAPH_PRINT_ABS_TIME 0x20 #define TRACE_GRAPH_PRINT_IRQS 0x40 #define TRACE_GRAPH_PRINT_TAIL 0x80 #define TRACE_GRAPH_SLEEP_TIME 0x100 #define TRACE_GRAPH_GRAPH_TIME 0x200 #define TRACE_GRAPH_PRINT_FILL_SHIFT 28 #define TRACE_GRAPH_PRINT_FILL_MASK (0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT) extern void ftrace_graph_sleep_time_control(bool enable); extern void ftrace_graph_graph_time_control(bool enable); extern enum print_line_t print_graph_function_flags(struct trace_iterator *iter, u32 flags); extern void print_graph_headers_flags(struct seq_file *s, u32 flags); extern void trace_print_graph_duration(unsigned long long duration, struct trace_seq *s); extern void graph_trace_open(struct trace_iterator *iter); extern void graph_trace_close(struct trace_iterator *iter); extern int __trace_graph_entry(struct trace_array *tr, struct ftrace_graph_ent *trace, unsigned long flags, int pc); extern void __trace_graph_return(struct trace_array *tr, struct ftrace_graph_ret *trace, unsigned long flags, int pc); #ifdef CONFIG_DYNAMIC_FTRACE extern struct ftrace_hash *ftrace_graph_hash; extern struct ftrace_hash *ftrace_graph_notrace_hash; static inline int ftrace_graph_addr(unsigned long addr) { int ret = 0; preempt_disable_notrace(); if (ftrace_hash_empty(ftrace_graph_hash)) { ret = 1; goto out; } if (ftrace_lookup_ip(ftrace_graph_hash, addr)) { /* * If no irqs are to be traced, but a set_graph_function * is set, and called by an interrupt handler, we still * want to trace it. */ if (in_irq()) trace_recursion_set(TRACE_IRQ_BIT); else trace_recursion_clear(TRACE_IRQ_BIT); ret = 1; } out: preempt_enable_notrace(); return ret; } static inline int ftrace_graph_notrace_addr(unsigned long addr) { int ret = 0; preempt_disable_notrace(); if (ftrace_lookup_ip(ftrace_graph_notrace_hash, addr)) ret = 1; preempt_enable_notrace(); return ret; } #else static inline int ftrace_graph_addr(unsigned long addr) { return 1; } static inline int ftrace_graph_notrace_addr(unsigned long addr) { return 0; } #endif /* CONFIG_DYNAMIC_FTRACE */ extern unsigned int fgraph_max_depth; static inline bool ftrace_graph_ignore_func(struct ftrace_graph_ent *trace) { /* trace it when it is-nested-in or is a function enabled. */ return !(trace->depth || ftrace_graph_addr(trace->func)) || (trace->depth < 0) || (fgraph_max_depth && trace->depth >= fgraph_max_depth); } #else /* CONFIG_FUNCTION_GRAPH_TRACER */ static inline enum print_line_t print_graph_function_flags(struct trace_iterator *iter, u32 flags) { return TRACE_TYPE_UNHANDLED; } #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ extern struct list_head ftrace_pids; #ifdef CONFIG_FUNCTION_TRACER struct ftrace_func_command { struct list_head list; char *name; int (*func)(struct trace_array *tr, struct ftrace_hash *hash, char *func, char *cmd, char *params, int enable); }; extern bool ftrace_filter_param __initdata; static inline int ftrace_trace_task(struct trace_array *tr) { return !this_cpu_read(tr->trace_buffer.data->ftrace_ignore_pid); } extern int ftrace_is_dead(void); int ftrace_create_function_files(struct trace_array *tr, struct dentry *parent); void ftrace_destroy_function_files(struct trace_array *tr); void ftrace_init_global_array_ops(struct trace_array *tr); void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func); void ftrace_reset_array_ops(struct trace_array *tr); int using_ftrace_ops_list_func(void); void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer); void ftrace_init_tracefs_toplevel(struct trace_array *tr, struct dentry *d_tracer); void ftrace_clear_pids(struct trace_array *tr); int init_function_trace(void); void ftrace_pid_follow_fork(struct trace_array *tr, bool enable); #else static inline int ftrace_trace_task(struct trace_array *tr) { return 1; } static inline int ftrace_is_dead(void) { return 0; } static inline int ftrace_create_function_files(struct trace_array *tr, struct dentry *parent) { return 0; } static inline void ftrace_destroy_function_files(struct trace_array *tr) { } static inline __init void ftrace_init_global_array_ops(struct trace_array *tr) { } static inline void ftrace_reset_array_ops(struct trace_array *tr) { } static inline void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d) { } static inline void ftrace_init_tracefs_toplevel(struct trace_array *tr, struct dentry *d) { } static inline void ftrace_clear_pids(struct trace_array *tr) { } static inline int init_function_trace(void) { return 0; } static inline void ftrace_pid_follow_fork(struct trace_array *tr, bool enable) { } /* ftace_func_t type is not defined, use macro instead of static inline */ #define ftrace_init_array_ops(tr, func) do { } while (0) #endif /* CONFIG_FUNCTION_TRACER */ #if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE) struct ftrace_probe_ops { void (*func)(unsigned long ip, unsigned long parent_ip, struct trace_array *tr, struct ftrace_probe_ops *ops, void *data); int (*init)(struct ftrace_probe_ops *ops, struct trace_array *tr, unsigned long ip, void *init_data, void **data); void (*free)(struct ftrace_probe_ops *ops, struct trace_array *tr, unsigned long ip, void *data); int (*print)(struct seq_file *m, unsigned long ip, struct ftrace_probe_ops *ops, void *data); }; struct ftrace_func_mapper; typedef int (*ftrace_mapper_func)(void *data); struct ftrace_func_mapper *allocate_ftrace_func_mapper(void); void **ftrace_func_mapper_find_ip(struct ftrace_func_mapper *mapper, unsigned long ip); int ftrace_func_mapper_add_ip(struct ftrace_func_mapper *mapper, unsigned long ip, void *data); void *ftrace_func_mapper_remove_ip(struct ftrace_func_mapper *mapper, unsigned long ip); void free_ftrace_func_mapper(struct ftrace_func_mapper *mapper, ftrace_mapper_func free_func); extern int register_ftrace_function_probe(char *glob, struct trace_array *tr, struct ftrace_probe_ops *ops, void *data); extern int unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr, struct ftrace_probe_ops *ops); extern void clear_ftrace_function_probes(struct trace_array *tr); int register_ftrace_command(struct ftrace_func_command *cmd); int unregister_ftrace_command(struct ftrace_func_command *cmd); void ftrace_create_filter_files(struct ftrace_ops *ops, struct dentry *parent); void ftrace_destroy_filter_files(struct ftrace_ops *ops); #else struct ftrace_func_command; static inline __init int register_ftrace_command(struct ftrace_func_command *cmd) { return -EINVAL; } static inline __init int unregister_ftrace_command(char *cmd_name) { return -EINVAL; } static inline void clear_ftrace_function_probes(struct trace_array *tr) { } /* * The ops parameter passed in is usually undefined. * This must be a macro. */ #define ftrace_create_filter_files(ops, parent) do { } while (0) #define ftrace_destroy_filter_files(ops) do { } while (0) #endif /* CONFIG_FUNCTION_TRACER && CONFIG_DYNAMIC_FTRACE */ bool ftrace_event_is_function(struct trace_event_call *call); /* * struct trace_parser - servers for reading the user input separated by spaces * @cont: set if the input is not complete - no final space char was found * @buffer: holds the parsed user input * @idx: user input length * @size: buffer size */ struct trace_parser { bool cont; char *buffer; unsigned idx; unsigned size; }; static inline bool trace_parser_loaded(struct trace_parser *parser) { return (parser->idx != 0); } static inline bool trace_parser_cont(struct trace_parser *parser) { return parser->cont; } static inline void trace_parser_clear(struct trace_parser *parser) { parser->cont = false; parser->idx = 0; } extern int trace_parser_get_init(struct trace_parser *parser, int size); extern void trace_parser_put(struct trace_parser *parser); extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf, size_t cnt, loff_t *ppos); /* * Only create function graph options if function graph is configured. */ #ifdef CONFIG_FUNCTION_GRAPH_TRACER # define FGRAPH_FLAGS \ C(DISPLAY_GRAPH, "display-graph"), #else # define FGRAPH_FLAGS #endif #ifdef CONFIG_BRANCH_TRACER # define BRANCH_FLAGS \ C(BRANCH, "branch"), #else # define BRANCH_FLAGS #endif #ifdef CONFIG_FUNCTION_TRACER # define FUNCTION_FLAGS \ C(FUNCTION, "function-trace"), \ C(FUNC_FORK, "function-fork"), # define FUNCTION_DEFAULT_FLAGS TRACE_ITER_FUNCTION #else # define FUNCTION_FLAGS # define FUNCTION_DEFAULT_FLAGS 0UL # define TRACE_ITER_FUNC_FORK 0UL #endif #ifdef CONFIG_STACKTRACE # define STACK_FLAGS \ C(STACKTRACE, "stacktrace"), #else # define STACK_FLAGS #endif /* * trace_iterator_flags is an enumeration that defines bit * positions into trace_flags that controls the output. * * NOTE: These bits must match the trace_options array in * trace.c (this macro guarantees it). */ #define TRACE_FLAGS \ C(PRINT_PARENT, "print-parent"), \ C(SYM_OFFSET, "sym-offset"), \ C(SYM_ADDR, "sym-addr"), \ C(VERBOSE, "verbose"), \ C(RAW, "raw"), \ C(HEX, "hex"), \ C(BIN, "bin"), \ C(BLOCK, "block"), \ C(PRINTK, "trace_printk"), \ C(ANNOTATE, "annotate"), \ C(USERSTACKTRACE, "userstacktrace"), \ C(SYM_USEROBJ, "sym-userobj"), \ C(PRINTK_MSGONLY, "printk-msg-only"), \ C(CONTEXT_INFO, "context-info"), /* Print pid/cpu/time */ \ C(LATENCY_FMT, "latency-format"), \ C(RECORD_CMD, "record-cmd"), \ C(RECORD_TGID, "record-tgid"), \ C(OVERWRITE, "overwrite"), \ C(STOP_ON_FREE, "disable_on_free"), \ C(IRQ_INFO, "irq-info"), \ C(MARKERS, "markers"), \ C(EVENT_FORK, "event-fork"), \ FUNCTION_FLAGS \ FGRAPH_FLAGS \ STACK_FLAGS \ BRANCH_FLAGS /* * By defining C, we can make TRACE_FLAGS a list of bit names * that will define the bits for the flag masks. */ #undef C #define C(a, b) TRACE_ITER_##a##_BIT enum trace_iterator_bits { TRACE_FLAGS /* Make sure we don't go more than we have bits for */ TRACE_ITER_LAST_BIT }; /* * By redefining C, we can make TRACE_FLAGS a list of masks that * use the bits as defined above. */ #undef C #define C(a, b) TRACE_ITER_##a = (1 << TRACE_ITER_##a##_BIT) enum trace_iterator_flags { TRACE_FLAGS }; /* * TRACE_ITER_SYM_MASK masks the options in trace_flags that * control the output of kernel symbols. */ #define TRACE_ITER_SYM_MASK \ (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR) extern struct tracer nop_trace; #ifdef CONFIG_BRANCH_TRACER extern int enable_branch_tracing(struct trace_array *tr); extern void disable_branch_tracing(void); static inline int trace_branch_enable(struct trace_array *tr) { if (tr->trace_flags & TRACE_ITER_BRANCH) return enable_branch_tracing(tr); return 0; } static inline void trace_branch_disable(void) { /* due to races, always disable */ disable_branch_tracing(); } #else static inline int trace_branch_enable(struct trace_array *tr) { return 0; } static inline void trace_branch_disable(void) { } #endif /* CONFIG_BRANCH_TRACER */ /* set ring buffers to default size if not already done so */ int tracing_update_buffers(void); struct ftrace_event_field { struct list_head link; const char *name; const char *type; int filter_type; int offset; int size; int is_signed; }; struct prog_entry; struct event_filter { struct prog_entry __rcu *prog; char *filter_string; }; struct event_subsystem { struct list_head list; const char *name; struct event_filter *filter; int ref_count; }; struct trace_subsystem_dir { struct list_head list; struct event_subsystem *subsystem; struct trace_array *tr; struct dentry *entry; int ref_count; int nr_events; }; extern int call_filter_check_discard(struct trace_event_call *call, void *rec, struct ring_buffer *buffer, struct ring_buffer_event *event); void trace_buffer_unlock_commit_regs(struct trace_array *tr, struct ring_buffer *buffer, struct ring_buffer_event *event, unsigned long flags, int pc, struct pt_regs *regs); static inline void trace_buffer_unlock_commit(struct trace_array *tr, struct ring_buffer *buffer, struct ring_buffer_event *event, unsigned long flags, int pc) { trace_buffer_unlock_commit_regs(tr, buffer, event, flags, pc, NULL); } DECLARE_PER_CPU(struct ring_buffer_event *, trace_buffered_event); DECLARE_PER_CPU(int, trace_buffered_event_cnt); void trace_buffered_event_disable(void); void trace_buffered_event_enable(void); static inline void __trace_event_discard_commit(struct ring_buffer *buffer, struct ring_buffer_event *event) { if (this_cpu_read(trace_buffered_event) == event) { /* Simply release the temp buffer */ this_cpu_dec(trace_buffered_event_cnt); return; } ring_buffer_discard_commit(buffer, event); } /* * Helper function for event_trigger_unlock_commit{_regs}(). * If there are event triggers attached to this event that requires * filtering against its fields, then they wil be called as the * entry already holds the field information of the current event. * * It also checks if the event should be discarded or not. * It is to be discarded if the event is soft disabled and the * event was only recorded to process triggers, or if the event * filter is active and this event did not match the filters. * * Returns true if the event is discarded, false otherwise. */ static inline bool __event_trigger_test_discard(struct trace_event_file *file, struct ring_buffer *buffer, struct ring_buffer_event *event, void *entry, enum event_trigger_type *tt) { unsigned long eflags = file->flags; if (eflags & EVENT_FILE_FL_TRIGGER_COND) *tt = event_triggers_call(file, entry, event); if (test_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &file->flags) || (unlikely(file->flags & EVENT_FILE_FL_FILTERED) && !filter_match_preds(file->filter, entry))) { __trace_event_discard_commit(buffer, event); return true; } return false; } /** * event_trigger_unlock_commit - handle triggers and finish event commit * @file: The file pointer assoctiated to the event * @buffer: The ring buffer that the event is being written to * @event: The event meta data in the ring buffer * @entry: The event itself * @irq_flags: The state of the interrupts at the start of the event * @pc: The state of the preempt count at the start of the event. * * This is a helper function to handle triggers that require data * from the event itself. It also tests the event against filters and * if the event is soft disabled and should be discarded. */ static inline void event_trigger_unlock_commit(struct trace_event_file *file, struct ring_buffer *buffer, struct ring_buffer_event *event, void *entry, unsigned long irq_flags, int pc) { enum event_trigger_type tt = ETT_NONE; if (!__event_trigger_test_discard(file, buffer, event, entry, &tt)) trace_buffer_unlock_commit(file->tr, buffer, event, irq_flags, pc); if (tt) event_triggers_post_call(file, tt); } /** * event_trigger_unlock_commit_regs - handle triggers and finish event commit * @file: The file pointer assoctiated to the event * @buffer: The ring buffer that the event is being written to * @event: The event meta data in the ring buffer * @entry: The event itself * @irq_flags: The state of the interrupts at the start of the event * @pc: The state of the preempt count at the start of the event. * * This is a helper function to handle triggers that require data * from the event itself. It also tests the event against filters and * if the event is soft disabled and should be discarded. * * Same as event_trigger_unlock_commit() but calls * trace_buffer_unlock_commit_regs() instead of trace_buffer_unlock_commit(). */ static inline void event_trigger_unlock_commit_regs(struct trace_event_file *file, struct ring_buffer *buffer, struct ring_buffer_event *event, void *entry, unsigned long irq_flags, int pc, struct pt_regs *regs) { enum event_trigger_type tt = ETT_NONE; if (!__event_trigger_test_discard(file, buffer, event, entry, &tt)) trace_buffer_unlock_commit_regs(file->tr, buffer, event, irq_flags, pc, regs); if (tt) event_triggers_post_call(file, tt); } #define FILTER_PRED_INVALID ((unsigned short)-1) #define FILTER_PRED_IS_RIGHT (1 << 15) #define FILTER_PRED_FOLD (1 << 15) /* * The max preds is the size of unsigned short with * two flags at the MSBs. One bit is used for both the IS_RIGHT * and FOLD flags. The other is reserved. * * 2^14 preds is way more than enough. */ #define MAX_FILTER_PRED 16384 struct filter_pred; struct regex; typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event); typedef int (*regex_match_func)(char *str, struct regex *r, int len); enum regex_type { MATCH_FULL = 0, MATCH_FRONT_ONLY, MATCH_MIDDLE_ONLY, MATCH_END_ONLY, MATCH_GLOB, }; struct regex { char pattern[MAX_FILTER_STR_VAL]; int len; int field_len; regex_match_func match; }; struct filter_pred { filter_pred_fn_t fn; u64 val; struct regex regex; unsigned short *ops; struct ftrace_event_field *field; int offset; int not; int op; }; static inline bool is_string_field(struct ftrace_event_field *field) { return field->filter_type == FILTER_DYN_STRING || field->filter_type == FILTER_STATIC_STRING || field->filter_type == FILTER_PTR_STRING || field->filter_type == FILTER_COMM; } static inline bool is_function_field(struct ftrace_event_field *field) { return field->filter_type == FILTER_TRACE_FN; } extern enum regex_type filter_parse_regex(char *buff, int len, char **search, int *not); extern void print_event_filter(struct trace_event_file *file, struct trace_seq *s); extern int apply_event_filter(struct trace_event_file *file, char *filter_string); extern int apply_subsystem_event_filter(struct trace_subsystem_dir *dir, char *filter_string); 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 trace_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 trace_event_call *call, char *name); extern void trace_event_enable_cmd_record(bool enable); extern void trace_event_enable_tgid_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 trace_event_file *__find_event_file(struct trace_array *tr, const char *system, const char *event); extern struct trace_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 READ_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 const struct file_operations event_hist_fops; #ifdef CONFIG_HIST_TRIGGERS extern int register_trigger_hist_cmd(void); extern int register_trigger_hist_enable_disable_cmds(void); #else static inline int register_trigger_hist_cmd(void) { return 0; } static inline int register_trigger_hist_enable_disable_cmds(void) { return 0; } #endif 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; bool paused; bool paused_tmp; struct list_head list; char *name; struct list_head named_list; struct event_trigger_data *named_data; }; /* Avoid typos */ #define ENABLE_EVENT_STR "enable_event" #define DISABLE_EVENT_STR "disable_event" #define ENABLE_HIST_STR "enable_hist" #define DISABLE_HIST_STR "disable_hist" struct enable_trigger_data { struct trace_event_file *file; bool enable; bool hist; }; extern int event_enable_trigger_print(struct seq_file *m, struct event_trigger_ops *ops, struct event_trigger_data *data); extern void event_enable_trigger_free(struct event_trigger_ops *ops, struct event_trigger_data *data); extern int event_enable_trigger_func(struct event_command *cmd_ops, struct trace_event_file *file, char *glob, char *cmd, char *param); extern int event_enable_register_trigger(char *glob, struct event_trigger_ops *ops, struct event_trigger_data *data, struct trace_event_file *file); extern void event_enable_unregister_trigger(char *glob, struct event_trigger_ops *ops, struct event_trigger_data *test, struct trace_event_file *file); extern void trigger_data_free(struct event_trigger_data *data); extern int event_trigger_init(struct event_trigger_ops *ops, struct event_trigger_data *data); extern int trace_event_trigger_enable_disable(struct trace_event_file *file, int trigger_enable); extern void update_cond_flag(struct trace_event_file *file); extern void unregister_trigger(char *glob, struct event_trigger_ops *ops, struct event_trigger_data *test, struct trace_event_file *file); extern int set_trigger_filter(char *filter_str, struct event_trigger_data *trigger_data, struct trace_event_file *file); extern struct event_trigger_data *find_named_trigger(const char *name); extern bool is_named_trigger(struct event_trigger_data *test); extern int save_named_trigger(const char *name, struct event_trigger_data *data); extern void del_named_trigger(struct event_trigger_data *data); extern void pause_named_trigger(struct event_trigger_data *data); extern void unpause_named_trigger(struct event_trigger_data *data); extern void set_named_trigger_data(struct event_trigger_data *data, struct event_trigger_data *named_data); extern struct event_trigger_data * get_named_trigger_data(struct event_trigger_data *data); extern int register_event_command(struct event_command *cmd); extern int unregister_event_command(struct event_command *cmd); extern int register_trigger_hist_enable_disable_cmds(void); /** * 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) along with * the trace record, rec. * * @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, void *rec, struct ring_buffer_event *rbe); 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/trace_events.h. * * @flags: See the enum event_command_flags below. * * All the methods below, except for @set_filter() and @unreg_all(), * 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). * * @unreg_all: An optional function called to remove all the triggers * from the list of triggers associated with the event. Called * when a trigger file is opened in truncate mode. * * @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; int flags; int (*func)(struct event_command *cmd_ops, struct trace_event_file *file, char *glob, char *cmd, char *params); int (*reg)(char *glob, struct event_trigger_ops *ops, struct event_trigger_data *data, struct trace_event_file *file); void (*unreg)(char *glob, struct event_trigger_ops *ops, struct event_trigger_data *data, struct trace_event_file *file); void (*unreg_all)(struct trace_event_file *file); int (*set_filter)(char *filter_str, struct event_trigger_data *data, struct trace_event_file *file); struct event_trigger_ops *(*get_trigger_ops)(char *cmd, char *param); }; /** * enum event_command_flags - flags for struct event_command * * @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. * * @NEEDS_REC: A flag that says whether or not this command needs * access to the trace record in order to perform its function, * regardless of whether or not it has a filter associated with * it (filters make a trigger require access to the trace record * but are not always present). */ enum event_command_flags { EVENT_CMD_FL_POST_TRIGGER = 1, EVENT_CMD_FL_NEEDS_REC = 2, }; static inline bool event_command_post_trigger(struct event_command *cmd_ops) { return cmd_ops->flags & EVENT_CMD_FL_POST_TRIGGER; } static inline bool event_command_needs_rec(struct event_command *cmd_ops) { return cmd_ops->flags & EVENT_CMD_FL_NEEDS_REC; } extern int trace_event_enable_disable(struct trace_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[]; extern const char *__start___tracepoint_str[]; extern const char *__stop___tracepoint_str[]; void trace_printk_control(bool enabled); void trace_printk_init_buffers(void); void trace_printk_start_comm(void); int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set); int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled); #define MAX_EVENT_NAME_LEN 64 extern int trace_run_command(const char *buf, int (*createfn)(int, char**)); extern ssize_t trace_parse_run_command(struct file *file, const char __user *buffer, size_t count, loff_t *ppos, int (*createfn)(int, char**)); /* * Normal trace_printk() and friends allocates special buffers * to do the manipulation, as well as saves the print formats * into sections to display. But the trace infrastructure wants * to use these without the added overhead at the price of being * a bit slower (used mainly for warnings, where we don't care * about performance). The internal_trace_puts() is for such * a purpose. */ #define internal_trace_puts(str) __trace_puts(_THIS_IP_, str, strlen(str)) #undef FTRACE_ENTRY #define FTRACE_ENTRY(call, struct_name, id, tstruct, print, filter) \ extern struct trace_event_call \ __aligned(4) event_##call; #undef FTRACE_ENTRY_DUP #define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print, filter) \ FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print), \ filter) #undef FTRACE_ENTRY_PACKED #define FTRACE_ENTRY_PACKED(call, struct_name, id, tstruct, print, filter) \ FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print), \ filter) #include "trace_entries.h" #if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER) int perf_ftrace_event_register(struct trace_event_call *call, enum trace_reg type, void *data); #else #define perf_ftrace_event_register NULL #endif #ifdef CONFIG_FTRACE_SYSCALLS void init_ftrace_syscalls(void); const char *get_syscall_name(int syscall); #else static inline void init_ftrace_syscalls(void) { } static inline const char *get_syscall_name(int syscall) { return NULL; } #endif #ifdef CONFIG_EVENT_TRACING void trace_event_init(void); void trace_event_eval_update(struct trace_eval_map **map, int len); #else static inline void __init trace_event_init(void) { } static inline void trace_event_eval_update(struct trace_eval_map **map, int len) { } #endif #ifdef CONFIG_TRACER_SNAPSHOT void tracing_snapshot_instance(struct trace_array *tr); int tracing_alloc_snapshot_instance(struct trace_array *tr); #else static inline void tracing_snapshot_instance(struct trace_array *tr) { } static inline int tracing_alloc_snapshot_instance(struct trace_array *tr) { return 0; } #endif extern struct trace_iterator *tracepoint_print_iter; #endif /* _LINUX_KERNEL_TRACE_H */