diff options
Diffstat (limited to 'kernel/trace/trace.c')
| -rw-r--r-- | kernel/trace/trace.c | 187 |
1 files changed, 142 insertions, 45 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 24c1f238255..9be67c5e5b0 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -73,7 +73,8 @@ static struct tracer_flags dummy_tracer_flags = { .opts = dummy_tracer_opt }; -static int dummy_set_flag(u32 old_flags, u32 bit, int set) +static int +dummy_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set) { return 0; } @@ -118,7 +119,7 @@ enum ftrace_dump_mode ftrace_dump_on_oops; /* When set, tracing will stop when a WARN*() is hit */ int __disable_trace_on_warning; -static int tracing_set_tracer(const char *buf); +static int tracing_set_tracer(struct trace_array *tr, const char *buf); #define MAX_TRACER_SIZE 100 static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata; @@ -180,6 +181,17 @@ static int __init set_trace_boot_options(char *str) } __setup("trace_options=", set_trace_boot_options); +static char trace_boot_clock_buf[MAX_TRACER_SIZE] __initdata; +static char *trace_boot_clock __initdata; + +static int __init set_trace_boot_clock(char *str) +{ + strlcpy(trace_boot_clock_buf, str, MAX_TRACER_SIZE); + trace_boot_clock = trace_boot_clock_buf; + return 0; +} +__setup("trace_clock=", set_trace_boot_clock); + unsigned long long ns2usecs(cycle_t nsec) { @@ -1230,7 +1242,7 @@ int register_tracer(struct tracer *type) printk(KERN_INFO "Starting tracer '%s'\n", type->name); /* Do we want this tracer to start on bootup? */ - tracing_set_tracer(type->name); + tracing_set_tracer(&global_trace, type->name); default_bootup_tracer = NULL; /* disable other selftests, since this will break it. */ tracing_selftest_disabled = true; @@ -3137,27 +3149,52 @@ static int tracing_open(struct inode *inode, struct file *file) return ret; } +/* + * Some tracers are not suitable for instance buffers. + * A tracer is always available for the global array (toplevel) + * or if it explicitly states that it is. + */ +static bool +trace_ok_for_array(struct tracer *t, struct trace_array *tr) +{ + return (tr->flags & TRACE_ARRAY_FL_GLOBAL) || t->allow_instances; +} + +/* Find the next tracer that this trace array may use */ +static struct tracer * +get_tracer_for_array(struct trace_array *tr, struct tracer *t) +{ + while (t && !trace_ok_for_array(t, tr)) + t = t->next; + + return t; +} + static void * t_next(struct seq_file *m, void *v, loff_t *pos) { + struct trace_array *tr = m->private; struct tracer *t = v; (*pos)++; if (t) - t = t->next; + t = get_tracer_for_array(tr, t->next); return t; } static void *t_start(struct seq_file *m, loff_t *pos) { + struct trace_array *tr = m->private; struct tracer *t; loff_t l = 0; mutex_lock(&trace_types_lock); - for (t = trace_types; t && l < *pos; t = t_next(m, t, &l)) - ; + + t = get_tracer_for_array(tr, trace_types); + for (; t && l < *pos; t = t_next(m, t, &l)) + ; return t; } @@ -3192,10 +3229,21 @@ static const struct seq_operations show_traces_seq_ops = { static int show_traces_open(struct inode *inode, struct file *file) { + struct trace_array *tr = inode->i_private; + struct seq_file *m; + int ret; + if (tracing_disabled) return -ENODEV; - return seq_open(file, &show_traces_seq_ops); + ret = seq_open(file, &show_traces_seq_ops); + if (ret) + return ret; + + m = file->private_data; + m->private = tr; + + return 0; } static ssize_t @@ -3355,13 +3403,14 @@ static int tracing_trace_options_show(struct seq_file *m, void *v) return 0; } -static int __set_tracer_option(struct tracer *trace, +static int __set_tracer_option(struct trace_array *tr, struct tracer_flags *tracer_flags, struct tracer_opt *opts, int neg) { + struct tracer *trace = tr->current_trace; int ret; - ret = trace->set_flag(tracer_flags->val, opts->bit, !neg); + ret = trace->set_flag(tr, tracer_flags->val, opts->bit, !neg); if (ret) return ret; @@ -3373,8 +3422,9 @@ static int __set_tracer_option(struct tracer *trace, } /* Try to assign a tracer specific option */ -static int set_tracer_option(struct tracer *trace, char *cmp, int neg) +static int set_tracer_option(struct trace_array *tr, char *cmp, int neg) { + struct tracer *trace = tr->current_trace; struct tracer_flags *tracer_flags = trace->flags; struct tracer_opt *opts = NULL; int i; @@ -3383,8 +3433,7 @@ static int set_tracer_option(struct tracer *trace, char *cmp, int neg) opts = &tracer_flags->opts[i]; if (strcmp(cmp, opts->name) == 0) - return __set_tracer_option(trace, trace->flags, - opts, neg); + return __set_tracer_option(tr, trace->flags, opts, neg); } return -EINVAL; @@ -3407,7 +3456,7 @@ int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled) /* Give the tracer a chance to approve the change */ if (tr->current_trace->flag_changed) - if (tr->current_trace->flag_changed(tr->current_trace, mask, !!enabled)) + if (tr->current_trace->flag_changed(tr, mask, !!enabled)) return -EINVAL; if (enabled) @@ -3456,7 +3505,7 @@ static int trace_set_options(struct trace_array *tr, char *option) /* If no option could be set, test the specific tracer options */ if (!trace_options[i]) - ret = set_tracer_option(tr->current_trace, cmp, neg); + ret = set_tracer_option(tr, cmp, neg); mutex_unlock(&trace_types_lock); @@ -3885,10 +3934,26 @@ create_trace_option_files(struct trace_array *tr, struct tracer *tracer); static void destroy_trace_option_files(struct trace_option_dentry *topts); -static int tracing_set_tracer(const char *buf) +/* + * Used to clear out the tracer before deletion of an instance. + * Must have trace_types_lock held. + */ +static void tracing_set_nop(struct trace_array *tr) +{ + if (tr->current_trace == &nop_trace) + return; + + tr->current_trace->enabled--; + + if (tr->current_trace->reset) + tr->current_trace->reset(tr); + + tr->current_trace = &nop_trace; +} + +static int tracing_set_tracer(struct trace_array *tr, const char *buf) { static struct trace_option_dentry *topts; - struct trace_array *tr = &global_trace; struct tracer *t; #ifdef CONFIG_TRACER_MAX_TRACE bool had_max_tr; @@ -3916,9 +3981,15 @@ static int tracing_set_tracer(const char *buf) if (t == tr->current_trace) goto out; + /* Some tracers are only allowed for the top level buffer */ + if (!trace_ok_for_array(t, tr)) { + ret = -EINVAL; + goto out; + } + trace_branch_disable(); - tr->current_trace->enabled = false; + tr->current_trace->enabled--; if (tr->current_trace->reset) tr->current_trace->reset(tr); @@ -3941,9 +4012,11 @@ static int tracing_set_tracer(const char *buf) free_snapshot(tr); } #endif - destroy_trace_option_files(topts); - - topts = create_trace_option_files(tr, t); + /* Currently, only the top instance has options */ + if (tr->flags & TRACE_ARRAY_FL_GLOBAL) { + destroy_trace_option_files(topts); + topts = create_trace_option_files(tr, t); + } #ifdef CONFIG_TRACER_MAX_TRACE if (t->use_max_tr && !had_max_tr) { @@ -3960,7 +4033,7 @@ static int tracing_set_tracer(const char *buf) } tr->current_trace = t; - tr->current_trace->enabled = true; + tr->current_trace->enabled++; trace_branch_enable(tr); out: mutex_unlock(&trace_types_lock); @@ -3972,6 +4045,7 @@ static ssize_t tracing_set_trace_write(struct file *filp, const char __user *ubuf, size_t cnt, loff_t *ppos) { + struct trace_array *tr = filp->private_data; char buf[MAX_TRACER_SIZE+1]; int i; size_t ret; @@ -3991,7 +4065,7 @@ tracing_set_trace_write(struct file *filp, const char __user *ubuf, for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) buf[i] = 0; - err = tracing_set_tracer(buf); + err = tracing_set_tracer(tr, buf); if (err) return err; @@ -4699,25 +4773,10 @@ static int tracing_clock_show(struct seq_file *m, void *v) return 0; } -static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, - size_t cnt, loff_t *fpos) +static int tracing_set_clock(struct trace_array *tr, const char *clockstr) { - struct seq_file *m = filp->private_data; - struct trace_array *tr = m->private; - char buf[64]; - const char *clockstr; int i; - if (cnt >= sizeof(buf)) - return -EINVAL; - - if (copy_from_user(&buf, ubuf, cnt)) - return -EFAULT; - - buf[cnt] = 0; - - clockstr = strstrip(buf); - for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) { if (strcmp(trace_clocks[i].name, clockstr) == 0) break; @@ -4745,6 +4804,32 @@ static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, mutex_unlock(&trace_types_lock); + return 0; +} + +static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, + size_t cnt, loff_t *fpos) +{ + struct seq_file *m = filp->private_data; + struct trace_array *tr = m->private; + char buf[64]; + const char *clockstr; + int ret; + + if (cnt >= sizeof(buf)) + return -EINVAL; + + if (copy_from_user(&buf, ubuf, cnt)) + return -EFAULT; + + buf[cnt] = 0; + + clockstr = strstrip(buf); + + ret = tracing_set_clock(tr, clockstr); + if (ret) + return ret; + *fpos += cnt; return cnt; @@ -5705,7 +5790,7 @@ trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, if (!!(topt->flags->val & topt->opt->bit) != val) { mutex_lock(&trace_types_lock); - ret = __set_tracer_option(topt->tr->current_trace, topt->flags, + ret = __set_tracer_option(topt->tr, topt->flags, topt->opt, !val); mutex_unlock(&trace_types_lock); if (ret) @@ -6112,7 +6197,9 @@ static int instance_delete(const char *name) list_del(&tr->list); + tracing_set_nop(tr); event_trace_del_tracer(tr); + ftrace_destroy_function_files(tr); debugfs_remove_recursive(tr->dir); free_percpu(tr->trace_buffer.data); ring_buffer_free(tr->trace_buffer.buffer); @@ -6207,6 +6294,12 @@ init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer) { int cpu; + trace_create_file("available_tracers", 0444, d_tracer, + tr, &show_traces_fops); + + trace_create_file("current_tracer", 0644, d_tracer, + tr, &set_tracer_fops); + trace_create_file("tracing_cpumask", 0644, d_tracer, tr, &tracing_cpumask_fops); @@ -6237,6 +6330,9 @@ init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer) trace_create_file("tracing_on", 0644, d_tracer, tr, &rb_simple_fops); + if (ftrace_create_function_files(tr, d_tracer)) + WARN(1, "Could not allocate function filter files"); + #ifdef CONFIG_TRACER_SNAPSHOT trace_create_file("snapshot", 0644, d_tracer, tr, &snapshot_fops); @@ -6259,12 +6355,6 @@ static __init int tracer_init_debugfs(void) init_tracer_debugfs(&global_trace, d_tracer); - trace_create_file("available_tracers", 0444, d_tracer, - &global_trace, &show_traces_fops); - - trace_create_file("current_tracer", 0644, d_tracer, - &global_trace, &set_tracer_fops); - #ifdef CONFIG_TRACER_MAX_TRACE trace_create_file("tracing_max_latency", 0644, d_tracer, &tracing_max_latency, &tracing_max_lat_fops); @@ -6527,6 +6617,13 @@ __init static int tracer_alloc_buffers(void) trace_init_cmdlines(); + if (trace_boot_clock) { + ret = tracing_set_clock(&global_trace, trace_boot_clock); + if (ret < 0) + pr_warning("Trace clock %s not defined, going back to default\n", + trace_boot_clock); + } + /* * register_tracer() might reference current_trace, so it * needs to be set before we register anything. This is |