diff options
Diffstat (limited to 'kernel/trace/trace.c')
| -rw-r--r-- | kernel/trace/trace.c | 454 |
1 files changed, 290 insertions, 164 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 6e79408..2198a63 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -214,12 +214,10 @@ __setup("alloc_snapshot", boot_alloc_snapshot); static char trace_boot_options_buf[MAX_TRACER_SIZE] __initdata; -static char *trace_boot_options __initdata; static int __init set_trace_boot_options(char *str) { strlcpy(trace_boot_options_buf, str, MAX_TRACER_SIZE); - trace_boot_options = trace_boot_options_buf; return 0; } __setup("trace_options=", set_trace_boot_options); @@ -250,6 +248,19 @@ unsigned long long ns2usecs(cycle_t nsec) return nsec; } +/* trace_flags holds trace_options default values */ +#define TRACE_DEFAULT_FLAGS \ + (FUNCTION_DEFAULT_FLAGS | \ + TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | \ + TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | \ + TRACE_ITER_RECORD_CMD | TRACE_ITER_OVERWRITE | \ + TRACE_ITER_IRQ_INFO | TRACE_ITER_MARKERS) + +/* trace_options that are only supported by global_trace */ +#define TOP_LEVEL_TRACE_FLAGS (TRACE_ITER_PRINTK | \ + TRACE_ITER_PRINTK_MSGONLY | TRACE_ITER_RECORD_CMD) + + /* * The global_trace is the descriptor that holds the tracing * buffers for the live tracing. For each CPU, it contains @@ -262,7 +273,9 @@ unsigned long long ns2usecs(cycle_t nsec) * pages for the buffer for that CPU. Each CPU has the same number * of pages allocated for its buffer. */ -static struct trace_array global_trace; +static struct trace_array global_trace = { + .trace_flags = TRACE_DEFAULT_FLAGS, +}; LIST_HEAD(ftrace_trace_arrays); @@ -468,11 +481,29 @@ static inline void trace_access_lock_init(void) #endif -/* trace_flags holds trace_options default values */ -unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | - TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME | - TRACE_ITER_GRAPH_TIME | TRACE_ITER_RECORD_CMD | TRACE_ITER_OVERWRITE | - TRACE_ITER_IRQ_INFO | TRACE_ITER_MARKERS | TRACE_ITER_FUNCTION; +#ifdef CONFIG_STACKTRACE +static void __ftrace_trace_stack(struct ring_buffer *buffer, + unsigned long flags, + int skip, int pc, struct pt_regs *regs); +static inline void ftrace_trace_stack(struct trace_array *tr, + struct ring_buffer *buffer, + unsigned long flags, + int skip, int pc, struct pt_regs *regs); + +#else +static inline void __ftrace_trace_stack(struct ring_buffer *buffer, + unsigned long flags, + int skip, int pc, struct pt_regs *regs) +{ +} +static inline void ftrace_trace_stack(struct trace_array *tr, + struct ring_buffer *buffer, + unsigned long flags, + int skip, int pc, struct pt_regs *regs) +{ +} + +#endif static void tracer_tracing_on(struct trace_array *tr) { @@ -518,7 +549,7 @@ int __trace_puts(unsigned long ip, const char *str, int size) int alloc; int pc; - if (!(trace_flags & TRACE_ITER_PRINTK)) + if (!(global_trace.trace_flags & TRACE_ITER_PRINTK)) return 0; pc = preempt_count(); @@ -548,7 +579,7 @@ int __trace_puts(unsigned long ip, const char *str, int size) entry->buf[size] = '\0'; __buffer_unlock_commit(buffer, event); - ftrace_trace_stack(buffer, irq_flags, 4, pc); + ftrace_trace_stack(&global_trace, buffer, irq_flags, 4, pc, NULL); return size; } @@ -568,7 +599,7 @@ int __trace_bputs(unsigned long ip, const char *str) int size = sizeof(struct bputs_entry); int pc; - if (!(trace_flags & TRACE_ITER_PRINTK)) + if (!(global_trace.trace_flags & TRACE_ITER_PRINTK)) return 0; pc = preempt_count(); @@ -588,7 +619,7 @@ int __trace_bputs(unsigned long ip, const char *str) entry->str = str; __buffer_unlock_commit(buffer, event); - ftrace_trace_stack(buffer, irq_flags, 4, pc); + ftrace_trace_stack(&global_trace, buffer, irq_flags, 4, pc, NULL); return 1; } @@ -834,34 +865,18 @@ unsigned long nsecs_to_usecs(unsigned long nsecs) return nsecs / 1000; } +/* + * TRACE_FLAGS is defined as a tuple matching bit masks with strings. + * It uses C(a, b) where 'a' is the enum name and 'b' is the string that + * matches it. By defining "C(a, b) b", TRACE_FLAGS becomes a list + * of strings in the order that the enums were defined. + */ +#undef C +#define C(a, b) b + /* These must match the bit postions in trace_iterator_flags */ static const char *trace_options[] = { - "print-parent", - "sym-offset", - "sym-addr", - "verbose", - "raw", - "hex", - "bin", - "block", - "stacktrace", - "trace_printk", - "ftrace_preempt", - "branch", - "annotate", - "userstacktrace", - "sym-userobj", - "printk-msg-only", - "context-info", - "latency-format", - "sleep-time", - "graph-time", - "record-cmd", - "overwrite", - "disable_on_free", - "irq-info", - "markers", - "function-trace", + TRACE_FLAGS NULL }; @@ -1204,13 +1219,17 @@ static inline int run_tracer_selftest(struct tracer *type) } #endif /* CONFIG_FTRACE_STARTUP_TEST */ +static void add_tracer_options(struct trace_array *tr, struct tracer *t); + +static void __init apply_trace_boot_options(void); + /** * register_tracer - register a tracer with the ftrace system. * @type - the plugin for the tracer * * Register a new plugin tracer. */ -int register_tracer(struct tracer *type) +int __init register_tracer(struct tracer *type) { struct tracer *t; int ret = 0; @@ -1253,6 +1272,7 @@ int register_tracer(struct tracer *type) type->next = trace_types; trace_types = type; + add_tracer_options(&global_trace, type); out: tracing_selftest_running = false; @@ -1268,6 +1288,9 @@ int register_tracer(struct tracer *type) /* Do we want this tracer to start on bootup? */ tracing_set_tracer(&global_trace, type->name); default_bootup_tracer = NULL; + + apply_trace_boot_options(); + /* disable other selftests, since this will break it. */ tracing_selftest_disabled = true; #ifdef CONFIG_FTRACE_STARTUP_TEST @@ -1671,23 +1694,16 @@ __buffer_unlock_commit(struct ring_buffer *buffer, struct ring_buffer_event *eve ring_buffer_unlock_commit(buffer, event); } -static inline void -__trace_buffer_unlock_commit(struct ring_buffer *buffer, - struct ring_buffer_event *event, - unsigned long flags, int pc) +void trace_buffer_unlock_commit(struct trace_array *tr, + struct ring_buffer *buffer, + struct ring_buffer_event *event, + unsigned long flags, int pc) { __buffer_unlock_commit(buffer, event); - ftrace_trace_stack(buffer, flags, 6, pc); + ftrace_trace_stack(tr, buffer, flags, 6, pc, NULL); ftrace_trace_userstack(buffer, flags, pc); } - -void trace_buffer_unlock_commit(struct ring_buffer *buffer, - struct ring_buffer_event *event, - unsigned long flags, int pc) -{ - __trace_buffer_unlock_commit(buffer, event, flags, pc); -} EXPORT_SYMBOL_GPL(trace_buffer_unlock_commit); static struct ring_buffer *temp_buffer; @@ -1729,22 +1745,15 @@ trace_current_buffer_lock_reserve(struct ring_buffer **current_rb, } EXPORT_SYMBOL_GPL(trace_current_buffer_lock_reserve); -void trace_current_buffer_unlock_commit(struct ring_buffer *buffer, - struct ring_buffer_event *event, - unsigned long flags, int pc) -{ - __trace_buffer_unlock_commit(buffer, event, flags, pc); -} -EXPORT_SYMBOL_GPL(trace_current_buffer_unlock_commit); - -void trace_buffer_unlock_commit_regs(struct ring_buffer *buffer, +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) { __buffer_unlock_commit(buffer, event); - ftrace_trace_stack_regs(buffer, flags, 0, pc, regs); + ftrace_trace_stack(tr, buffer, flags, 6, pc, regs); ftrace_trace_userstack(buffer, flags, pc); } EXPORT_SYMBOL_GPL(trace_buffer_unlock_commit_regs); @@ -1873,24 +1882,17 @@ static void __ftrace_trace_stack(struct ring_buffer *buffer, } -void ftrace_trace_stack_regs(struct ring_buffer *buffer, unsigned long flags, - int skip, int pc, struct pt_regs *regs) +static inline void ftrace_trace_stack(struct trace_array *tr, + struct ring_buffer *buffer, + unsigned long flags, + int skip, int pc, struct pt_regs *regs) { - if (!(trace_flags & TRACE_ITER_STACKTRACE)) + if (!(tr->trace_flags & TRACE_ITER_STACKTRACE)) return; __ftrace_trace_stack(buffer, flags, skip, pc, regs); } -void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags, - int skip, int pc) -{ - if (!(trace_flags & TRACE_ITER_STACKTRACE)) - return; - - __ftrace_trace_stack(buffer, flags, skip, pc, NULL); -} - void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, int pc) { @@ -1929,7 +1931,7 @@ ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc) struct userstack_entry *entry; struct stack_trace trace; - if (!(trace_flags & TRACE_ITER_USERSTACKTRACE)) + if (!(global_trace.trace_flags & TRACE_ITER_USERSTACKTRACE)) return; /* @@ -2173,7 +2175,7 @@ int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) memcpy(entry->buf, tbuffer, sizeof(u32) * len); if (!call_filter_check_discard(call, entry, buffer, event)) { __buffer_unlock_commit(buffer, event); - ftrace_trace_stack(buffer, flags, 6, pc); + ftrace_trace_stack(tr, buffer, flags, 6, pc, NULL); } out: @@ -2225,7 +2227,7 @@ __trace_array_vprintk(struct ring_buffer *buffer, memcpy(&entry->buf, tbuffer, len + 1); if (!call_filter_check_discard(call, entry, buffer, event)) { __buffer_unlock_commit(buffer, event); - ftrace_trace_stack(buffer, flags, 6, pc); + ftrace_trace_stack(&global_trace, buffer, flags, 6, pc, NULL); } out: preempt_enable_notrace(); @@ -2246,7 +2248,7 @@ int trace_array_printk(struct trace_array *tr, int ret; va_list ap; - if (!(trace_flags & TRACE_ITER_PRINTK)) + if (!(global_trace.trace_flags & TRACE_ITER_PRINTK)) return 0; va_start(ap, fmt); @@ -2261,7 +2263,7 @@ int trace_array_printk_buf(struct ring_buffer *buffer, int ret; va_list ap; - if (!(trace_flags & TRACE_ITER_PRINTK)) + if (!(global_trace.trace_flags & TRACE_ITER_PRINTK)) return 0; va_start(ap, fmt); @@ -2602,7 +2604,7 @@ static void print_func_help_header_irq(struct trace_buffer *buf, struct seq_file void print_trace_header(struct seq_file *m, struct trace_iterator *iter) { - unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); + unsigned long sym_flags = (global_trace.trace_flags & TRACE_ITER_SYM_MASK); struct trace_buffer *buf = iter->trace_buffer; struct trace_array_cpu *data = per_cpu_ptr(buf->data, buf->cpu); struct tracer *type = iter->trace; @@ -2664,20 +2666,22 @@ print_trace_header(struct seq_file *m, struct trace_iterator *iter) static void test_cpu_buff_start(struct trace_iterator *iter) { struct trace_seq *s = &iter->seq; + struct trace_array *tr = iter->tr; - if (!(trace_flags & TRACE_ITER_ANNOTATE)) + if (!(tr->trace_flags & TRACE_ITER_ANNOTATE)) return; if (!(iter->iter_flags & TRACE_FILE_ANNOTATE)) return; - if (cpumask_test_cpu(iter->cpu, iter->started)) + if (iter->started && cpumask_test_cpu(iter->cpu, iter->started)) return; if (per_cpu_ptr(iter->trace_buffer->data, iter->cpu)->skipped_entries) return; - cpumask_set_cpu(iter->cpu, iter->started); + if (iter->started) + cpumask_set_cpu(iter->cpu, iter->started); /* Don't print started cpu buffer for the first entry of the trace */ if (iter->idx > 1) @@ -2687,8 +2691,9 @@ static void test_cpu_buff_start(struct trace_iterator *iter) static enum print_line_t print_trace_fmt(struct trace_iterator *iter) { + struct trace_array *tr = iter->tr; struct trace_seq *s = &iter->seq; - unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); + unsigned long sym_flags = (tr->trace_flags & TRACE_ITER_SYM_MASK); struct trace_entry *entry; struct trace_event *event; @@ -2698,7 +2703,7 @@ static enum print_line_t print_trace_fmt(struct trace_iterator *iter) event = ftrace_find_event(entry->type); - if (trace_flags & TRACE_ITER_CONTEXT_INFO) { + if (tr->trace_flags & TRACE_ITER_CONTEXT_INFO) { if (iter->iter_flags & TRACE_FILE_LAT_FMT) trace_print_lat_context(iter); else @@ -2718,13 +2723,14 @@ static enum print_line_t print_trace_fmt(struct trace_iterator *iter) static enum print_line_t print_raw_fmt(struct trace_iterator *iter) { + struct trace_array *tr = iter->tr; struct trace_seq *s = &iter->seq; struct trace_entry *entry; struct trace_event *event; entry = iter->ent; - if (trace_flags & TRACE_ITER_CONTEXT_INFO) + if (tr->trace_flags & TRACE_ITER_CONTEXT_INFO) trace_seq_printf(s, "%d %d %llu ", entry->pid, iter->cpu, iter->ts); @@ -2742,6 +2748,7 @@ static enum print_line_t print_raw_fmt(struct trace_iterator *iter) static enum print_line_t print_hex_fmt(struct trace_iterator *iter) { + struct trace_array *tr = iter->tr; struct trace_seq *s = &iter->seq; unsigned char newline = '\n'; struct trace_entry *entry; @@ -2749,7 +2756,7 @@ static enum print_line_t print_hex_fmt(struct trace_iterator *iter) entry = iter->ent; - if (trace_flags & TRACE_ITER_CONTEXT_INFO) { + if (tr->trace_flags & TRACE_ITER_CONTEXT_INFO) { SEQ_PUT_HEX_FIELD(s, entry->pid); SEQ_PUT_HEX_FIELD(s, iter->cpu); SEQ_PUT_HEX_FIELD(s, iter->ts); @@ -2771,13 +2778,14 @@ static enum print_line_t print_hex_fmt(struct trace_iterator *iter) static enum print_line_t print_bin_fmt(struct trace_iterator *iter) { + struct trace_array *tr = iter->tr; struct trace_seq *s = &iter->seq; struct trace_entry *entry; struct trace_event *event; entry = iter->ent; - if (trace_flags & TRACE_ITER_CONTEXT_INFO) { + if (tr->trace_flags & TRACE_ITER_CONTEXT_INFO) { SEQ_PUT_FIELD(s, entry->pid); SEQ_PUT_FIELD(s, iter->cpu); SEQ_PUT_FIELD(s, iter->ts); @@ -2826,6 +2834,8 @@ int trace_empty(struct trace_iterator *iter) /* Called with trace_event_read_lock() held. */ enum print_line_t print_trace_line(struct trace_iterator *iter) { + struct trace_array *tr = iter->tr; + unsigned long trace_flags = tr->trace_flags; enum print_line_t ret; if (iter->lost_events) { @@ -2871,6 +2881,7 @@ enum print_line_t print_trace_line(struct trace_iterator *iter) void trace_latency_header(struct seq_file *m) { struct trace_iterator *iter = m->private; + struct trace_array *tr = iter->tr; /* print nothing if the buffers are empty */ if (trace_empty(iter)) @@ -2879,13 +2890,15 @@ void trace_latency_header(struct seq_file *m) if (iter->iter_flags & TRACE_FILE_LAT_FMT) print_trace_header(m, iter); - if (!(trace_flags & TRACE_ITER_VERBOSE)) + if (!(tr->trace_flags & TRACE_ITER_VERBOSE)) print_lat_help_header(m); } void trace_default_header(struct seq_file *m) { struct trace_iterator *iter = m->private; + struct trace_array *tr = iter->tr; + unsigned long trace_flags = tr->trace_flags; if (!(trace_flags & TRACE_ITER_CONTEXT_INFO)) return; @@ -3230,7 +3243,7 @@ static int tracing_open(struct inode *inode, struct file *file) iter = __tracing_open(inode, file, false); if (IS_ERR(iter)) ret = PTR_ERR(iter); - else if (trace_flags & TRACE_ITER_LATENCY_FMT) + else if (tr->trace_flags & TRACE_ITER_LATENCY_FMT) iter->iter_flags |= TRACE_FILE_LAT_FMT; } @@ -3477,7 +3490,7 @@ static int tracing_trace_options_show(struct seq_file *m, void *v) trace_opts = tr->current_trace->flags->opts; for (i = 0; trace_options[i]; i++) { - if (trace_flags & (1 << i)) + if (tr->trace_flags & (1 << i)) seq_printf(m, "%s\n", trace_options[i]); else seq_printf(m, "no%s\n", trace_options[i]); @@ -3542,7 +3555,7 @@ int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set) int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled) { /* do nothing if flag is already set */ - if (!!(trace_flags & mask) == !!enabled) + if (!!(tr->trace_flags & mask) == !!enabled) return 0; /* Give the tracer a chance to approve the change */ @@ -3551,9 +3564,9 @@ int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled) return -EINVAL; if (enabled) - trace_flags |= mask; + tr->trace_flags |= mask; else - trace_flags &= ~mask; + tr->trace_flags &= ~mask; if (mask == TRACE_ITER_RECORD_CMD) trace_event_enable_cmd_record(enabled); @@ -3565,8 +3578,10 @@ int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled) #endif } - if (mask == TRACE_ITER_PRINTK) + if (mask == TRACE_ITER_PRINTK) { trace_printk_start_stop_comm(enabled); + trace_printk_control(enabled); + } return 0; } @@ -3577,6 +3592,7 @@ static int trace_set_options(struct trace_array *tr, char *option) int neg = 0; int ret = -ENODEV; int i; + size_t orig_len = strlen(option); cmp = strstrip(option); @@ -3600,9 +3616,36 @@ static int trace_set_options(struct trace_array *tr, char *option) mutex_unlock(&trace_types_lock); + /* + * If the first trailing whitespace is replaced with '\0' by strstrip, + * turn it back into a space. + */ + if (orig_len > strlen(option)) + option[strlen(option)] = ' '; + return ret; } +static void __init apply_trace_boot_options(void) +{ + char *buf = trace_boot_options_buf; + char *option; + + while (true) { + option = strsep(&buf, ","); + + if (!option) + break; + + if (*option) + trace_set_options(&global_trace, option); + + /* Put back the comma to allow this to be called again */ + if (buf) + *(buf - 1) = ','; + } +} + static ssize_t tracing_trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, loff_t *ppos) @@ -4297,11 +4340,8 @@ int tracing_update_buffers(void) struct trace_option_dentry; -static struct trace_option_dentry * -create_trace_option_files(struct trace_array *tr, struct tracer *tracer); - static void -destroy_trace_option_files(struct trace_option_dentry *topts); +create_trace_option_files(struct trace_array *tr, struct tracer *tracer); /* * Used to clear out the tracer before deletion of an instance. @@ -4320,20 +4360,13 @@ static void tracing_set_nop(struct trace_array *tr) tr->current_trace = &nop_trace; } -static void update_tracer_options(struct trace_array *tr, struct tracer *t) +static void add_tracer_options(struct trace_array *tr, struct tracer *t) { - static struct trace_option_dentry *topts; - /* Only enable if the directory has been created already. */ if (!tr->dir) return; - /* Currently, only the top instance has options */ - if (!(tr->flags & TRACE_ARRAY_FL_GLOBAL)) - return; - - destroy_trace_option_files(topts); - topts = create_trace_option_files(tr, t); + create_trace_option_files(tr, t); } static int tracing_set_tracer(struct trace_array *tr, const char *buf) @@ -4402,7 +4435,6 @@ static int tracing_set_tracer(struct trace_array *tr, const char *buf) free_snapshot(tr); } #endif - update_tracer_options(tr, t); #ifdef CONFIG_TRACER_MAX_TRACE if (t->use_max_tr && !had_max_tr) { @@ -4569,7 +4601,7 @@ static int tracing_open_pipe(struct inode *inode, struct file *filp) /* trace pipe does not show start of buffer */ cpumask_setall(iter->started); - if (trace_flags & TRACE_ITER_LATENCY_FMT) + if (tr->trace_flags & TRACE_ITER_LATENCY_FMT) iter->iter_flags |= TRACE_FILE_LAT_FMT; /* Output in nanoseconds only if we are using a clock in nanoseconds. */ @@ -4626,11 +4658,13 @@ static int tracing_release_pipe(struct inode *inode, struct file *file) static unsigned int trace_poll(struct trace_iterator *iter, struct file *filp, poll_table *poll_table) { + struct trace_array *tr = iter->tr; + /* Iterators are static, they should be filled or empty */ if (trace_buffer_iter(iter, iter->cpu_file)) return POLLIN | POLLRDNORM; - if (trace_flags & TRACE_ITER_BLOCK) + if (tr->trace_flags & TRACE_ITER_BLOCK) /* * Always select as readable when in blocking mode */ @@ -5047,7 +5081,7 @@ tracing_free_buffer_release(struct inode *inode, struct file *filp) struct trace_array *tr = inode->i_private; /* disable tracing ? */ - if (trace_flags & TRACE_ITER_STOP_ON_FREE) + if (tr->trace_flags & TRACE_ITER_STOP_ON_FREE) tracer_tracing_off(tr); /* resize the ring buffer to 0 */ tracing_resize_ring_buffer(tr, 0, RING_BUFFER_ALL_CPUS); @@ -5080,7 +5114,7 @@ tracing_mark_write(struct file *filp, const char __user *ubuf, if (tracing_disabled) return -EINVAL; - if (!(trace_flags & TRACE_ITER_MARKERS)) + if (!(tr->trace_flags & TRACE_ITER_MARKERS)) return -EINVAL; if (cnt > TRACE_BUF_SIZE) @@ -6132,13 +6166,6 @@ tracing_init_tracefs_percpu(struct trace_array *tr, long cpu) #include "trace_selftest.c" #endif -struct trace_option_dentry { - struct tracer_opt *opt; - struct tracer_flags *flags; - struct trace_array *tr; - struct dentry *entry; -}; - static ssize_t trace_options_read(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos) @@ -6191,14 +6218,51 @@ static const struct file_operations trace_options_fops = { .llseek = generic_file_llseek, }; +/* + * In order to pass in both the trace_array descriptor as well as the index + * to the flag that the trace option file represents, the trace_array + * has a character array of trace_flags_index[], which holds the index + * of the bit for the flag it represents. index[0] == 0, index[1] == 1, etc. + * The address of this character array is passed to the flag option file + * read/write callbacks. + * + * In order to extract both the index and the trace_array descriptor, + * get_tr_index() uses the following algorithm. + * + * idx = *ptr; + * + * As the pointer itself contains the address of the index (remember + * index[1] == 1). + * + * Then to get the trace_array descriptor, by subtracting that index + * from the ptr, we get to the start of the index itself. + * + * ptr - idx == &index[0] + * + * Then a simple container_of() from that pointer gets us to the + * trace_array descriptor. + */ +static void get_tr_index(void *data, struct trace_array **ptr, + unsigned int *pindex) +{ + *pindex = *(unsigned char *)data; + + *ptr = container_of(data - *pindex, struct trace_array, + trace_flags_index); +} + static ssize_t trace_options_core_read(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos) { - long index = (long)filp->private_data; + void *tr_index = filp->private_data; + struct trace_array *tr; + unsigned int index; char *buf; - if (trace_flags & (1 << index)) + get_tr_index(tr_index, &tr, &index); + + if (tr->trace_flags & (1 << index)) buf = "1\n"; else buf = "0\n"; @@ -6210,11 +6274,14 @@ static ssize_t trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, loff_t *ppos) { - struct trace_array *tr = &global_trace; - long index = (long)filp->private_data; + void *tr_index = filp->private_data; + struct trace_array *tr; + unsigned int index; unsigned long val; int ret; + get_tr_index(tr_index, &tr, &index); + ret = kstrtoul_from_user(ubuf, cnt, 10, &val); if (ret) return ret; @@ -6298,21 +6365,39 @@ create_trace_option_file(struct trace_array *tr, } -static struct trace_option_dentry * +static void create_trace_option_files(struct trace_array *tr, struct tracer *tracer) { struct trace_option_dentry *topts; + struct trace_options *tr_topts; struct tracer_flags *flags; struct tracer_opt *opts; int cnt; + int i; if (!tracer) - return NULL; + return; flags = tracer->flags; if (!flags || !flags->opts) - return NULL; + return; + + /* + * If this is an instance, only create flags for tracers + * the instance may have. + */ + if (!trace_ok_for_array(tracer, tr)) + return; + + for (i = 0; i < tr->nr_topts; i++) { + /* + * Check if these flags have already been added. + * Some tracers share flags. + */ + if (tr->topts[i].tracer->flags == tracer->flags) + return; + } opts = flags->opts; @@ -6321,27 +6406,27 @@ create_trace_option_files(struct trace_array *tr, struct tracer *tracer) topts = kcalloc(cnt + 1, sizeof(*topts), GFP_KERNEL); if (!topts) - return NULL; - - for (cnt = 0; opts[cnt].name; cnt++) - create_trace_option_file(tr, &topts[cnt], flags, - &opts[cnt]); - - return topts; -} - -static void -destroy_trace_option_files(struct trace_option_dentry *topts) -{ - int cnt; + return; - if (!topts) + tr_topts = krealloc(tr->topts, sizeof(*tr->topts) * (tr->nr_topts + 1), + GFP_KERNEL); + if (!tr_topts) { + kfree(topts); return; + } - for (cnt = 0; topts[cnt].opt; cnt++) - tracefs_remove(topts[cnt].entry); + tr->topts = tr_topts; + tr->topts[tr->nr_topts].tracer = tracer; + tr->topts[tr->nr_topts].topts = topts; + tr->nr_topts++; - kfree(topts); + for (cnt = 0; opts[cnt].name; cnt++) { + create_trace_option_file(tr, &topts[cnt], flags, + &opts[cnt]); + WARN_ONCE(topts[cnt].entry == NULL, + "Failed to create trace option: %s", + opts[cnt].name); + } } static struct dentry * @@ -6354,21 +6439,26 @@ create_trace_option_core_file(struct trace_array *tr, if (!t_options) return NULL; - return trace_create_file(option, 0644, t_options, (void *)index, - &trace_options_core_fops); + return trace_create_file(option, 0644, t_options, + (void *)&tr->trace_flags_index[index], + &trace_options_core_fops); } -static __init void create_trace_options_dir(struct trace_array *tr) +static void create_trace_options_dir(struct trace_array *tr) { struct dentry *t_options; + bool top_level = tr == &global_trace; int i; t_options = trace_options_init_dentry(tr); if (!t_options) return; - for (i = 0; trace_options[i]; i++) - create_trace_option_core_file(tr, trace_options[i], i); + for (i = 0; trace_options[i]; i++) { + if (top_level || + !((1 << i) & TOP_LEVEL_TRACE_FLAGS)) + create_trace_option_core_file(tr, trace_options[i], i); + } } static ssize_t @@ -6435,7 +6525,7 @@ allocate_trace_buffer(struct trace_array *tr, struct trace_buffer *buf, int size { enum ring_buffer_flags rb_flags; - rb_flags = trace_flags & TRACE_ITER_OVERWRITE ? RB_FL_OVERWRITE : 0; + rb_flags = tr->trace_flags & TRACE_ITER_OVERWRITE ? RB_FL_OVERWRITE : 0; buf->tr = tr; @@ -6505,6 +6595,30 @@ static void free_trace_buffers(struct trace_array *tr) #endif } +static void init_trace_flags_index(struct trace_array *tr) +{ + int i; + + /* Used by the trace options files */ + for (i = 0; i < TRACE_FLAGS_MAX_SIZE; i++) + tr->trace_flags_index[i] = i; +} + +static void __update_tracer_options(struct trace_array *tr) +{ + struct tracer *t; + + for (t = trace_types; t; t = t->next) + add_tracer_options(tr, t); +} + +static void update_tracer_options(struct trace_array *tr) +{ + mutex_lock(&trace_types_lock); + __update_tracer_options(tr); + mutex_unlock(&trace_types_lock); +} + static int instance_mkdir(const char *name) { struct trace_array *tr; @@ -6530,6 +6644,8 @@ static int instance_mkdir(const char *name) if (!alloc_cpumask_var(&tr->tracing_cpumask, GFP_KERNEL)) goto out_free_tr; + tr->trace_flags = global_trace.trace_flags; + cpumask_copy(tr->tracing_cpumask, cpu_all_mask); raw_spin_lock_init(&tr->start_lock); @@ -6555,6 +6671,8 @@ static int instance_mkdir(const char *name) } init_tracer_tracefs(tr, tr->dir); + init_trace_flags_index(tr); + __update_tracer_options(tr); list_add(&tr->list, &ftrace_trace_arrays); @@ -6580,6 +6698,7 @@ static int instance_rmdir(const char *name) struct trace_array *tr; int found = 0; int ret; + int i; mutex_lock(&trace_types_lock); @@ -6602,9 +6721,14 @@ static int instance_rmdir(const char *name) tracing_set_nop(tr); event_trace_del_tracer(tr); ftrace_destroy_function_files(tr); - debugfs_remove_recursive(tr->dir); + tracefs_remove_recursive(tr->dir); free_trace_buffers(tr); + for (i = 0; i < tr->nr_topts; i++) { + kfree(tr->topts[i].topts); + } + kfree(tr->topts); + kfree(tr->name); kfree(tr); @@ -6666,6 +6790,8 @@ init_tracer_tracefs(struct trace_array *tr, struct dentry *d_tracer) trace_create_file("tracing_on", 0644, d_tracer, tr, &rb_simple_fops); + create_trace_options_dir(tr); + #ifdef CONFIG_TRACER_MAX_TRACE trace_create_file("tracing_max_latency", 0644, d_tracer, &tr->max_latency, &tracing_max_lat_fops); @@ -6861,11 +6987,7 @@ static __init int tracer_init_tracefs(void) create_trace_instances(d_tracer); - create_trace_options_dir(&global_trace); - - /* If the tracer was started via cmdline, create options for it here */ - if (global_trace.current_trace != &nop_trace) - update_tracer_options(&global_trace, global_trace.current_trace); + update_tracer_options(&global_trace); return 0; } @@ -6964,6 +7086,7 @@ void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) /* use static because iter can be a bit big for the stack */ static struct trace_iterator iter; static atomic_t dump_running; + struct trace_array *tr = &global_trace; unsigned int old_userobj; unsigned long flags; int cnt = 0, cpu; @@ -6993,10 +7116,10 @@ void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) atomic_inc(&per_cpu_ptr(iter.trace_buffer->data, cpu)->disabled); } - old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ; + old_userobj = tr->trace_flags & TRACE_ITER_SYM_USEROBJ; /* don't look at user memory in panic mode */ - trace_flags &= ~TRACE_ITER_SYM_USEROBJ; + tr->trace_flags &= ~TRACE_ITER_SYM_USEROBJ; switch (oops_dump_mode) { case DUMP_ALL: @@ -7059,7 +7182,7 @@ void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) printk(KERN_TRACE "---------------------------------\n"); out_enable: - trace_flags |= old_userobj; + tr->trace_flags |= old_userobj; for_each_tracing_cpu(cpu) { atomic_dec(&per_cpu_ptr(iter.trace_buffer->data, cpu)->disabled); @@ -7074,6 +7197,12 @@ __init static int tracer_alloc_buffers(void) int ring_buf_size; int ret = -ENOMEM; + /* + * Make sure we don't accidently add more trace options + * than we have bits for. + */ + BUILD_BUG_ON(TRACE_ITER_LAST_BIT > TRACE_FLAGS_MAX_SIZE); + if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) goto out; @@ -7132,6 +7261,8 @@ __init static int tracer_alloc_buffers(void) ftrace_init_global_array_ops(&global_trace); + init_trace_flags_index(&global_trace); + register_tracer(&nop_trace); /* All seems OK, enable tracing */ @@ -7148,12 +7279,7 @@ __init static int tracer_alloc_buffers(void) INIT_LIST_HEAD(&global_trace.events); list_add(&global_trace.list, &ftrace_trace_arrays); - while (trace_boot_options) { - char *option; - - option = strsep(&trace_boot_options, ","); - trace_set_options(&global_trace, option); - } + apply_trace_boot_options(); register_snapshot_cmd(); |
