diff options
| -rw-r--r-- | include/linux/ftrace_event.h | 3 | ||||
| -rw-r--r-- | include/linux/module.h | 4 | ||||
| -rw-r--r-- | include/linux/trace_seq.h | 2 | ||||
| -rw-r--r-- | include/trace/ftrace.h | 1 | ||||
| -rw-r--r-- | kernel/module.c | 7 | ||||
| -rw-r--r-- | kernel/trace/trace_events.c | 128 |
6 files changed, 113 insertions, 32 deletions
diff --git a/include/linux/ftrace_event.h b/include/linux/ftrace_event.h index 17810853b4f..75f3ac01a87 100644 --- a/include/linux/ftrace_event.h +++ b/include/linux/ftrace_event.h @@ -7,6 +7,7 @@ struct trace_array; struct tracer; +struct dentry; /* * The trace entry - the most basic unit of tracing. This is what @@ -87,6 +88,7 @@ struct ftrace_event_call { char *name; char *system; struct dentry *dir; + struct trace_event *event; int enabled; int (*regfunc)(void); void (*unregfunc)(void); @@ -97,6 +99,7 @@ struct ftrace_event_call { struct list_head fields; int n_preds; struct filter_pred **preds; + void *mod; #ifdef CONFIG_EVENT_PROFILE atomic_t profile_count; diff --git a/include/linux/module.h b/include/linux/module.h index 627ac082e2a..6155fa44168 100644 --- a/include/linux/module.h +++ b/include/linux/module.h @@ -337,6 +337,10 @@ struct module const char **trace_bprintk_fmt_start; unsigned int num_trace_bprintk_fmt; #endif +#ifdef CONFIG_EVENT_TRACING + struct ftrace_event_call *trace_events; + unsigned int num_trace_events; +#endif #ifdef CONFIG_MODULE_UNLOAD /* What modules depend on me? */ diff --git a/include/linux/trace_seq.h b/include/linux/trace_seq.h index 28051da876d..15ca2c71af1 100644 --- a/include/linux/trace_seq.h +++ b/include/linux/trace_seq.h @@ -1,6 +1,8 @@ #ifndef _LINUX_TRACE_SEQ_H #define _LINUX_TRACE_SEQ_H +#include <linux/fs.h> + /* * Trace sequences are used to allow a function to call several other functions * to create a string of data to use (up to a max of PAGE_SIZE. diff --git a/include/trace/ftrace.h b/include/trace/ftrace.h index 955b967acd7..60c5323bee6 100644 --- a/include/trace/ftrace.h +++ b/include/trace/ftrace.h @@ -477,6 +477,7 @@ __attribute__((__aligned__(4))) \ __attribute__((section("_ftrace_events"))) event_##call = { \ .name = #call, \ .system = __stringify(TRACE_SYSTEM), \ + .event = &ftrace_event_type_##call, \ .raw_init = ftrace_raw_init_event_##call, \ .regfunc = ftrace_raw_reg_event_##call, \ .unregfunc = ftrace_raw_unreg_event_##call, \ diff --git a/kernel/module.c b/kernel/module.c index e797812a4d9..a0394706f10 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -18,6 +18,7 @@ */ #include <linux/module.h> #include <linux/moduleloader.h> +#include <linux/ftrace_event.h> #include <linux/init.h> #include <linux/kallsyms.h> #include <linux/fs.h> @@ -2172,6 +2173,12 @@ static noinline struct module *load_module(void __user *umod, sizeof(*mod->tracepoints), &mod->num_tracepoints); #endif +#ifdef CONFIG_EVENT_TRACING + mod->trace_events = section_objs(hdr, sechdrs, secstrings, + "_ftrace_events", + sizeof(*mod->trace_events), + &mod->num_trace_events); +#endif #ifdef CONFIG_MODVERSIONS if ((mod->num_syms && !mod->crcs) diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index 8b9e621b80b..a4b177720a6 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -713,7 +713,13 @@ event_subsystem_dir(const char *name, struct dentry *d_events) return d_events; } - system->name = name; + system->name = kstrdup(name, GFP_KERNEL); + if (!system->name) { + debugfs_remove(system->entry); + kfree(system); + return d_events; + } + list_add(&system->list, &event_subsystems); system->preds = NULL; @@ -738,7 +744,7 @@ event_create_dir(struct ftrace_event_call *call, struct dentry *d_events) * If the trace point header did not define TRACE_SYSTEM * then the system would be called "TRACE_SYSTEM". */ - if (strcmp(call->system, "TRACE_SYSTEM") != 0) + if (strcmp(call->system, TRACE_SYSTEM) != 0) d_events = event_subsystem_dir(call->system, d_events); if (call->raw_init) { @@ -757,21 +763,13 @@ event_create_dir(struct ftrace_event_call *call, struct dentry *d_events) return -1; } - if (call->regfunc) { - entry = debugfs_create_file("enable", 0644, call->dir, call, - &ftrace_enable_fops); - if (!entry) - pr_warning("Could not create debugfs " - "'%s/enable' entry\n", call->name); - } + if (call->regfunc) + entry = trace_create_file("enable", 0644, call->dir, call, + &ftrace_enable_fops); - if (call->id) { - entry = debugfs_create_file("id", 0444, call->dir, call, - &ftrace_event_id_fops); - if (!entry) - pr_warning("Could not create debugfs '%s/id' entry\n", - call->name); - } + if (call->id) + entry = trace_create_file("id", 0444, call->dir, call, + &ftrace_event_id_fops); if (call->define_fields) { ret = call->define_fields(); @@ -780,40 +778,102 @@ event_create_dir(struct ftrace_event_call *call, struct dentry *d_events) " events/%s\n", call->name); return ret; } - entry = debugfs_create_file("filter", 0644, call->dir, call, - &ftrace_event_filter_fops); - if (!entry) - pr_warning("Could not create debugfs " - "'%s/filter' entry\n", call->name); + entry = trace_create_file("filter", 0644, call->dir, call, + &ftrace_event_filter_fops); } /* A trace may not want to export its format */ if (!call->show_format) return 0; - entry = debugfs_create_file("format", 0444, call->dir, call, - &ftrace_event_format_fops); - if (!entry) - pr_warning("Could not create debugfs " - "'%s/format' entry\n", call->name); + entry = trace_create_file("format", 0444, call->dir, call, + &ftrace_event_format_fops); return 0; } +#define for_each_event(event, start, end) \ + for (event = start; \ + (unsigned long)event < (unsigned long)end; \ + event++) + +static void trace_module_add_events(struct module *mod) +{ + struct ftrace_event_call *call, *start, *end; + struct dentry *d_events; + + start = mod->trace_events; + end = mod->trace_events + mod->num_trace_events; + + if (start == end) + return; + + d_events = event_trace_events_dir(); + if (!d_events) + return; + + for_each_event(call, start, end) { + /* The linker may leave blanks */ + if (!call->name) + continue; + call->mod = mod; + list_add(&call->list, &ftrace_events); + event_create_dir(call, d_events); + } +} + +static void trace_module_remove_events(struct module *mod) +{ + struct ftrace_event_call *call, *p; + + list_for_each_entry_safe(call, p, &ftrace_events, list) { + if (call->mod == mod) { + if (call->enabled) { + call->enabled = 0; + call->unregfunc(); + } + if (call->event) + unregister_ftrace_event(call->event); + debugfs_remove_recursive(call->dir); + list_del(&call->list); + } + } +} + +int trace_module_notify(struct notifier_block *self, + unsigned long val, void *data) +{ + struct module *mod = data; + + mutex_lock(&event_mutex); + switch (val) { + case MODULE_STATE_COMING: + trace_module_add_events(mod); + break; + case MODULE_STATE_GOING: + trace_module_remove_events(mod); + break; + } + mutex_unlock(&event_mutex); + + return 0; +} + +struct notifier_block trace_module_nb = { + .notifier_call = trace_module_notify, + .priority = 0, +}; + extern struct ftrace_event_call __start_ftrace_events[]; extern struct ftrace_event_call __stop_ftrace_events[]; -#define for_each_event(event) \ - for (event = __start_ftrace_events; \ - (unsigned long)event < (unsigned long)__stop_ftrace_events; \ - event++) - static __init int event_trace_init(void) { struct ftrace_event_call *call; struct dentry *d_tracer; struct dentry *entry; struct dentry *d_events; + int ret; d_tracer = tracing_init_dentry(); if (!d_tracer) @@ -837,7 +897,7 @@ static __init int event_trace_init(void) if (!d_events) return 0; - for_each_event(call) { + for_each_event(call, __start_ftrace_events, __stop_ftrace_events) { /* The linker may leave blanks */ if (!call->name) continue; @@ -845,6 +905,10 @@ static __init int event_trace_init(void) event_create_dir(call, d_events); } + ret = register_module_notifier(&trace_module_nb); + if (!ret) + pr_warning("Failed to register trace events module notifier\n"); + return 0; } fs_initcall(event_trace_init); |