diff options
Diffstat (limited to 'kernel/trace/trace_events.c')
| -rw-r--r-- | kernel/trace/trace_events.c | 404 |
1 files changed, 160 insertions, 244 deletions
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index 29a7ebcfb42..2de53628689 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -27,12 +27,6 @@ DEFINE_MUTEX(event_mutex); -DEFINE_MUTEX(event_storage_mutex); -EXPORT_SYMBOL_GPL(event_storage_mutex); - -char event_storage[EVENT_STORAGE_SIZE]; -EXPORT_SYMBOL_GPL(event_storage); - LIST_HEAD(ftrace_events); static LIST_HEAD(ftrace_common_fields); @@ -194,29 +188,60 @@ int trace_event_raw_init(struct ftrace_event_call *call) } EXPORT_SYMBOL_GPL(trace_event_raw_init); +void *ftrace_event_buffer_reserve(struct ftrace_event_buffer *fbuffer, + struct ftrace_event_file *ftrace_file, + unsigned long len) +{ + struct ftrace_event_call *event_call = ftrace_file->event_call; + + local_save_flags(fbuffer->flags); + fbuffer->pc = preempt_count(); + fbuffer->ftrace_file = ftrace_file; + + fbuffer->event = + trace_event_buffer_lock_reserve(&fbuffer->buffer, ftrace_file, + event_call->event.type, len, + fbuffer->flags, fbuffer->pc); + if (!fbuffer->event) + return NULL; + + fbuffer->entry = ring_buffer_event_data(fbuffer->event); + return fbuffer->entry; +} +EXPORT_SYMBOL_GPL(ftrace_event_buffer_reserve); + +void ftrace_event_buffer_commit(struct ftrace_event_buffer *fbuffer) +{ + event_trigger_unlock_commit(fbuffer->ftrace_file, fbuffer->buffer, + fbuffer->event, fbuffer->entry, + fbuffer->flags, fbuffer->pc); +} +EXPORT_SYMBOL_GPL(ftrace_event_buffer_commit); + int ftrace_event_reg(struct ftrace_event_call *call, enum trace_reg type, void *data) { struct ftrace_event_file *file = data; + WARN_ON(!(call->flags & TRACE_EVENT_FL_TRACEPOINT)); switch (type) { case TRACE_REG_REGISTER: - return tracepoint_probe_register(call->name, + return tracepoint_probe_register(call->tp, call->class->probe, file); case TRACE_REG_UNREGISTER: - tracepoint_probe_unregister(call->name, + tracepoint_probe_unregister(call->tp, call->class->probe, file); return 0; #ifdef CONFIG_PERF_EVENTS case TRACE_REG_PERF_REGISTER: - return tracepoint_probe_register(call->name, + return tracepoint_probe_register(call->tp, call->class->perf_probe, call); case TRACE_REG_PERF_UNREGISTER: - tracepoint_probe_unregister(call->name, + tracepoint_probe_unregister(call->tp, call->class->perf_probe, call); return 0; @@ -328,7 +353,7 @@ static int __ftrace_event_enable_disable(struct ftrace_event_file *file, if (ret) { tracing_stop_cmdline_record(); pr_info("event trace: Could not enable event " - "%s\n", call->name); + "%s\n", ftrace_event_name(call)); break; } set_bit(FTRACE_EVENT_FL_ENABLED_BIT, &file->flags); @@ -342,6 +367,12 @@ static int __ftrace_event_enable_disable(struct ftrace_event_file *file, return ret; } +int trace_event_enable_disable(struct ftrace_event_file *file, + int enable, int soft_disable) +{ + return __ftrace_event_enable_disable(file, enable, soft_disable); +} + static int ftrace_event_enable_disable(struct ftrace_event_file *file, int enable) { @@ -421,11 +452,6 @@ static void remove_subsystem(struct ftrace_subsystem_dir *dir) } } -static void *event_file_data(struct file *filp) -{ - return ACCESS_ONCE(file_inode(filp)->i_private); -} - static void remove_event_file_dir(struct ftrace_event_file *file) { struct dentry *dir = file->dir; @@ -444,6 +470,7 @@ static void remove_event_file_dir(struct ftrace_event_file *file) list_del(&file->list); remove_subsystem(file->system); + free_event_filter(file->filter); kmem_cache_free(file_cachep, file); } @@ -456,27 +483,29 @@ __ftrace_set_clr_event_nolock(struct trace_array *tr, const char *match, { struct ftrace_event_file *file; struct ftrace_event_call *call; + const char *name; int ret = -EINVAL; list_for_each_entry(file, &tr->events, list) { call = file->event_call; + name = ftrace_event_name(call); - if (!call->name || !call->class || !call->class->reg) + if (!name || !call->class || !call->class->reg) continue; if (call->flags & TRACE_EVENT_FL_IGNORE_ENABLE) continue; if (match && - strcmp(match, call->name) != 0 && + strcmp(match, name) != 0 && strcmp(match, call->class->system) != 0) continue; if (sub && strcmp(sub, call->class->system) != 0) continue; - if (event && strcmp(event, call->name) != 0) + if (event && strcmp(event, name) != 0) continue; ftrace_event_enable_disable(file, set); @@ -546,6 +575,9 @@ int trace_set_clr_event(const char *system, const char *event, int set) { struct trace_array *tr = top_trace_array(); + if (!tr) + return -ENODEV; + return __ftrace_set_clr_event(tr, NULL, system, event, set); } EXPORT_SYMBOL_GPL(trace_set_clr_event); @@ -674,7 +706,7 @@ static int t_show(struct seq_file *m, void *v) if (strcmp(call->class->system, TRACE_SYSTEM) != 0) seq_printf(m, "%s:", call->class->system); - seq_printf(m, "%s\n", call->name); + seq_printf(m, "%s\n", ftrace_event_name(call)); return 0; } @@ -767,7 +799,7 @@ system_enable_read(struct file *filp, char __user *ubuf, size_t cnt, mutex_lock(&event_mutex); list_for_each_entry(file, &tr->events, list) { call = file->event_call; - if (!call->name || !call->class || !call->class->reg) + if (!ftrace_event_name(call) || !call->class || !call->class->reg) continue; if (system && strcmp(call->class->system, system->name) != 0) @@ -882,7 +914,7 @@ static int f_show(struct seq_file *m, void *v) switch ((unsigned long)v) { case FORMAT_HEADER: - seq_printf(m, "name: %s\n", call->name); + seq_printf(m, "name: %s\n", ftrace_event_name(call)); seq_printf(m, "ID: %d\n", call->event.type); seq_printf(m, "format:\n"); return 0; @@ -989,7 +1021,7 @@ static ssize_t event_filter_read(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos) { - struct ftrace_event_call *call; + struct ftrace_event_file *file; struct trace_seq *s; int r = -ENODEV; @@ -1004,12 +1036,12 @@ event_filter_read(struct file *filp, char __user *ubuf, size_t cnt, trace_seq_init(s); mutex_lock(&event_mutex); - call = event_file_data(filp); - if (call) - print_event_filter(call, s); + file = event_file_data(filp); + if (file) + print_event_filter(file, s); mutex_unlock(&event_mutex); - if (call) + if (file) r = simple_read_from_buffer(ubuf, cnt, ppos, s->buffer, s->len); kfree(s); @@ -1021,7 +1053,7 @@ static ssize_t event_filter_write(struct file *filp, const char __user *ubuf, size_t cnt, loff_t *ppos) { - struct ftrace_event_call *call; + struct ftrace_event_file *file; char *buf; int err = -ENODEV; @@ -1039,9 +1071,9 @@ event_filter_write(struct file *filp, const char __user *ubuf, size_t cnt, buf[cnt] = '\0'; mutex_lock(&event_mutex); - call = event_file_data(filp); - if (call) - err = apply_event_filter(call, buf); + file = event_file_data(filp); + if (file) + err = apply_event_filter(file, buf); mutex_unlock(&event_mutex); free_page((unsigned long) buf); @@ -1062,6 +1094,9 @@ static int subsystem_open(struct inode *inode, struct file *filp) struct trace_array *tr; int ret; + if (tracing_is_disabled()) + return -ENODEV; + /* Make sure the system still exists */ mutex_lock(&trace_types_lock); mutex_lock(&event_mutex); @@ -1108,6 +1143,9 @@ static int system_tr_open(struct inode *inode, struct file *filp) struct trace_array *tr = inode->i_private; int ret; + if (tracing_is_disabled()) + return -ENODEV; + if (trace_array_get(tr) < 0) return -ENODEV; @@ -1124,11 +1162,12 @@ static int system_tr_open(struct inode *inode, struct file *filp) if (ret < 0) { trace_array_put(tr); kfree(dir); + return ret; } filp->private_data = dir; - return ret; + return 0; } static int subsystem_release(struct inode *inode, struct file *file) @@ -1489,17 +1528,13 @@ event_subsystem_dir(struct trace_array *tr, const char *name, } static int -event_create_dir(struct dentry *parent, - struct ftrace_event_file *file, - const struct file_operations *id, - const struct file_operations *enable, - const struct file_operations *filter, - const struct file_operations *format) +event_create_dir(struct dentry *parent, struct ftrace_event_file *file) { struct ftrace_event_call *call = file->event_call; struct trace_array *tr = file->tr; struct list_head *head; struct dentry *d_events; + const char *name; int ret; /* @@ -1513,21 +1548,23 @@ event_create_dir(struct dentry *parent, } else d_events = parent; - file->dir = debugfs_create_dir(call->name, d_events); + name = ftrace_event_name(call); + file->dir = debugfs_create_dir(name, d_events); if (!file->dir) { pr_warning("Could not create debugfs '%s' directory\n", - call->name); + name); return -1; } if (call->class->reg && !(call->flags & TRACE_EVENT_FL_IGNORE_ENABLE)) trace_create_file("enable", 0644, file->dir, file, - enable); + &ftrace_enable_fops); #ifdef CONFIG_PERF_EVENTS if (call->event.type && call->class->reg) trace_create_file("id", 0444, file->dir, - (void *)(long)call->event.type, id); + (void *)(long)call->event.type, + &ftrace_event_id_fops); #endif /* @@ -1539,15 +1576,18 @@ event_create_dir(struct dentry *parent, ret = call->class->define_fields(call); if (ret < 0) { pr_warning("Could not initialize trace point" - " events/%s\n", call->name); + " events/%s\n", name); return -1; } } - trace_create_file("filter", 0644, file->dir, call, - filter); + trace_create_file("filter", 0644, file->dir, file, + &ftrace_event_filter_fops); + + trace_create_file("trigger", 0644, file->dir, file, + &event_trigger_fops); trace_create_file("format", 0444, file->dir, call, - format); + &ftrace_event_format_fops); return 0; } @@ -1581,6 +1621,7 @@ static void event_remove(struct ftrace_event_call *call) if (file->event_call != call) continue; ftrace_event_enable_disable(file, 0); + destroy_preds(file); /* * The do_for_each_event_file() is * a double loop. After finding the call for this @@ -1599,15 +1640,17 @@ static void event_remove(struct ftrace_event_call *call) static int event_init(struct ftrace_event_call *call) { int ret = 0; + const char *name; - if (WARN_ON(!call->name)) + name = ftrace_event_name(call); + if (WARN_ON(!name)) return -EINVAL; if (call->class->raw_init) { ret = call->class->raw_init(call); if (ret < 0 && ret != -ENOSYS) pr_warn("Could not initialize trace events/%s\n", - call->name); + name); } return ret; @@ -1641,6 +1684,8 @@ trace_create_new_event(struct ftrace_event_call *call, file->event_call = call; file->tr = tr; atomic_set(&file->sm_ref, 0); + atomic_set(&file->tm_ref, 0); + INIT_LIST_HEAD(&file->triggers); list_add(&file->list, &tr->events); return file; @@ -1648,12 +1693,7 @@ trace_create_new_event(struct ftrace_event_call *call, /* Add an event to a trace directory */ static int -__trace_add_new_event(struct ftrace_event_call *call, - struct trace_array *tr, - const struct file_operations *id, - const struct file_operations *enable, - const struct file_operations *filter, - const struct file_operations *format) +__trace_add_new_event(struct ftrace_event_call *call, struct trace_array *tr) { struct ftrace_event_file *file; @@ -1661,7 +1701,7 @@ __trace_add_new_event(struct ftrace_event_call *call, if (!file) return -ENOMEM; - return event_create_dir(tr->event_dir, file, id, enable, filter, format); + return event_create_dir(tr->event_dir, file); } /* @@ -1683,8 +1723,7 @@ __trace_early_add_new_event(struct ftrace_event_call *call, } struct ftrace_module_file_ops; -static void __add_event_to_tracers(struct ftrace_event_call *call, - struct ftrace_module_file_ops *file_ops); +static void __add_event_to_tracers(struct ftrace_event_call *call); /* Add an additional event_call dynamically */ int trace_add_event_call(struct ftrace_event_call *call) @@ -1695,7 +1734,7 @@ int trace_add_event_call(struct ftrace_event_call *call) ret = __register_event(call, NULL); if (ret >= 0) - __add_event_to_tracers(call, NULL); + __add_event_to_tracers(call); mutex_unlock(&event_mutex); mutex_unlock(&trace_types_lock); @@ -1710,7 +1749,7 @@ static void __trace_remove_event_call(struct ftrace_event_call *call) { event_remove(call); trace_destroy_fields(call); - destroy_preds(call); + destroy_call_preds(call); } static int probe_remove_event_call(struct ftrace_event_call *call) @@ -1769,100 +1808,31 @@ int trace_remove_event_call(struct ftrace_event_call *call) #ifdef CONFIG_MODULES -static LIST_HEAD(ftrace_module_file_list); - -/* - * Modules must own their file_operations to keep up with - * reference counting. - */ -struct ftrace_module_file_ops { - struct list_head list; - struct module *mod; - struct file_operations id; - struct file_operations enable; - struct file_operations format; - struct file_operations filter; -}; - -static struct ftrace_module_file_ops * -find_ftrace_file_ops(struct ftrace_module_file_ops *file_ops, struct module *mod) -{ - /* - * As event_calls are added in groups by module, - * when we find one file_ops, we don't need to search for - * each call in that module, as the rest should be the - * same. Only search for a new one if the last one did - * not match. - */ - if (file_ops && mod == file_ops->mod) - return file_ops; - - list_for_each_entry(file_ops, &ftrace_module_file_list, list) { - if (file_ops->mod == mod) - return file_ops; - } - return NULL; -} - -static struct ftrace_module_file_ops * -trace_create_file_ops(struct module *mod) -{ - struct ftrace_module_file_ops *file_ops; - - /* - * This is a bit of a PITA. To allow for correct reference - * counting, modules must "own" their file_operations. - * To do this, we allocate the file operations that will be - * used in the event directory. - */ - - file_ops = kmalloc(sizeof(*file_ops), GFP_KERNEL); - if (!file_ops) - return NULL; - - file_ops->mod = mod; - - file_ops->id = ftrace_event_id_fops; - file_ops->id.owner = mod; - - file_ops->enable = ftrace_enable_fops; - file_ops->enable.owner = mod; - - file_ops->filter = ftrace_event_filter_fops; - file_ops->filter.owner = mod; - - file_ops->format = ftrace_event_format_fops; - file_ops->format.owner = mod; - - list_add(&file_ops->list, &ftrace_module_file_list); - - return file_ops; -} - static void trace_module_add_events(struct module *mod) { - struct ftrace_module_file_ops *file_ops = NULL; struct ftrace_event_call **call, **start, **end; - start = mod->trace_events; - end = mod->trace_events + mod->num_trace_events; - - if (start == end) + if (!mod->num_trace_events) return; - file_ops = trace_create_file_ops(mod); - if (!file_ops) + /* Don't add infrastructure for mods without tracepoints */ + if (trace_module_has_bad_taint(mod)) { + pr_err("%s: module has bad taint, not creating trace events\n", + mod->name); return; + } + + start = mod->trace_events; + end = mod->trace_events + mod->num_trace_events; for_each_event(call, start, end) { __register_event(*call, mod); - __add_event_to_tracers(*call, file_ops); + __add_event_to_tracers(*call); } } static void trace_module_remove_events(struct module *mod) { - struct ftrace_module_file_ops *file_ops; struct ftrace_event_call *call, *p; bool clear_trace = false; @@ -1874,16 +1844,6 @@ static void trace_module_remove_events(struct module *mod) __trace_remove_event_call(call); } } - - /* Now free the file_operations */ - list_for_each_entry(file_ops, &ftrace_module_file_list, list) { - if (file_ops->mod == mod) - break; - } - if (&file_ops->list != &ftrace_module_file_list) { - list_del(&file_ops->list); - kfree(file_ops); - } up_write(&trace_event_sem); /* @@ -1919,109 +1879,65 @@ static int trace_module_notify(struct notifier_block *self, return 0; } -static int -__trace_add_new_mod_event(struct ftrace_event_call *call, - struct trace_array *tr, - struct ftrace_module_file_ops *file_ops) -{ - return __trace_add_new_event(call, tr, - &file_ops->id, &file_ops->enable, - &file_ops->filter, &file_ops->format); -} - -#else -static inline struct ftrace_module_file_ops * -find_ftrace_file_ops(struct ftrace_module_file_ops *file_ops, struct module *mod) -{ - return NULL; -} -static inline int trace_module_notify(struct notifier_block *self, - unsigned long val, void *data) -{ - return 0; -} -static inline int -__trace_add_new_mod_event(struct ftrace_event_call *call, - struct trace_array *tr, - struct ftrace_module_file_ops *file_ops) -{ - return -ENODEV; -} +static struct notifier_block trace_module_nb = { + .notifier_call = trace_module_notify, + .priority = 0, +}; #endif /* CONFIG_MODULES */ /* Create a new event directory structure for a trace directory. */ static void __trace_add_event_dirs(struct trace_array *tr) { - struct ftrace_module_file_ops *file_ops = NULL; struct ftrace_event_call *call; int ret; list_for_each_entry(call, &ftrace_events, list) { - if (call->mod) { - /* - * Directories for events by modules need to - * keep module ref counts when opened (as we don't - * want the module to disappear when reading one - * of these files). The file_ops keep account of - * the module ref count. - */ - file_ops = find_ftrace_file_ops(file_ops, call->mod); - if (!file_ops) - continue; /* Warn? */ - ret = __trace_add_new_mod_event(call, tr, file_ops); - if (ret < 0) - pr_warning("Could not create directory for event %s\n", - call->name); - continue; - } - ret = __trace_add_new_event(call, tr, - &ftrace_event_id_fops, - &ftrace_enable_fops, - &ftrace_event_filter_fops, - &ftrace_event_format_fops); + ret = __trace_add_new_event(call, tr); if (ret < 0) pr_warning("Could not create directory for event %s\n", - call->name); + ftrace_event_name(call)); } } -#ifdef CONFIG_DYNAMIC_FTRACE - -/* Avoid typos */ -#define ENABLE_EVENT_STR "enable_event" -#define DISABLE_EVENT_STR "disable_event" - -struct event_probe_data { - struct ftrace_event_file *file; - unsigned long count; - int ref; - bool enable; -}; - -static struct ftrace_event_file * +struct ftrace_event_file * find_event_file(struct trace_array *tr, const char *system, const char *event) { struct ftrace_event_file *file; struct ftrace_event_call *call; + const char *name; list_for_each_entry(file, &tr->events, list) { call = file->event_call; + name = ftrace_event_name(call); - if (!call->name || !call->class || !call->class->reg) + if (!name || !call->class || !call->class->reg) continue; if (call->flags & TRACE_EVENT_FL_IGNORE_ENABLE) continue; - if (strcmp(event, call->name) == 0 && + if (strcmp(event, name) == 0 && strcmp(system, call->class->system) == 0) return file; } return NULL; } +#ifdef CONFIG_DYNAMIC_FTRACE + +/* Avoid typos */ +#define ENABLE_EVENT_STR "enable_event" +#define DISABLE_EVENT_STR "disable_event" + +struct event_probe_data { + struct ftrace_event_file *file; + unsigned long count; + int ref; + bool enable; +}; + static void event_enable_probe(unsigned long ip, unsigned long parent_ip, void **_data) { @@ -2070,7 +1986,7 @@ event_enable_print(struct seq_file *m, unsigned long ip, seq_printf(m, "%s:%s:%s", data->enable ? ENABLE_EVENT_STR : DISABLE_EVENT_STR, data->file->event_call->class->system, - data->file->event_call->name); + ftrace_event_name(data->file->event_call)); if (data->count == -1) seq_printf(m, ":unlimited\n"); @@ -2153,6 +2069,9 @@ event_enable_func(struct ftrace_hash *hash, bool enable; int ret; + if (!tr) + return -ENODEV; + /* hash funcs only work with set_ftrace_filter */ if (!enabled || !param) return -EINVAL; @@ -2287,14 +2206,10 @@ __trace_early_add_event_dirs(struct trace_array *tr) list_for_each_entry(file, &tr->events, list) { - ret = event_create_dir(tr->event_dir, file, - &ftrace_event_id_fops, - &ftrace_enable_fops, - &ftrace_event_filter_fops, - &ftrace_event_format_fops); + ret = event_create_dir(tr->event_dir, file); if (ret < 0) pr_warning("Could not create directory for event %s\n", - file->event_call->name); + ftrace_event_name(file->event_call)); } } @@ -2318,7 +2233,7 @@ __trace_early_add_events(struct trace_array *tr) ret = __trace_early_add_new_event(call, tr); if (ret < 0) pr_warning("Could not create early event %s\n", - call->name); + ftrace_event_name(call)); } } @@ -2332,29 +2247,14 @@ __trace_remove_event_dirs(struct trace_array *tr) remove_event_file_dir(file); } -static void -__add_event_to_tracers(struct ftrace_event_call *call, - struct ftrace_module_file_ops *file_ops) +static void __add_event_to_tracers(struct ftrace_event_call *call) { struct trace_array *tr; - list_for_each_entry(tr, &ftrace_trace_arrays, list) { - if (file_ops) - __trace_add_new_mod_event(call, tr, file_ops); - else - __trace_add_new_event(call, tr, - &ftrace_event_id_fops, - &ftrace_enable_fops, - &ftrace_event_filter_fops, - &ftrace_event_format_fops); - } + list_for_each_entry(tr, &ftrace_trace_arrays, list) + __trace_add_new_event(call, tr); } -static 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[]; @@ -2467,9 +2367,15 @@ int event_trace_del_tracer(struct trace_array *tr) { mutex_lock(&event_mutex); + /* Disable any event triggers and associated soft-disabled events */ + clear_event_triggers(tr); + /* Disable any running events */ __ftrace_set_clr_event_nolock(tr, NULL, NULL, NULL, 0); + /* Access to events are within rcu_read_lock_sched() */ + synchronize_sched(); + down_write(&trace_event_sem); __trace_remove_event_dirs(tr); debugfs_remove_recursive(tr->event_dir); @@ -2497,6 +2403,9 @@ static __init int event_trace_enable(void) char *token; int ret; + if (!tr) + return -ENODEV; + for_each_event(iter, __start_ftrace_events, __stop_ftrace_events) { call = *iter; @@ -2530,6 +2439,8 @@ static __init int event_trace_enable(void) register_event_cmds(); + register_trigger_cmds(); + return 0; } @@ -2541,6 +2452,8 @@ static __init int event_trace_init(void) int ret; tr = top_trace_array(); + if (!tr) + return -ENODEV; d_tracer = tracing_init_dentry(); if (!d_tracer) @@ -2559,10 +2472,11 @@ static __init int event_trace_init(void) if (ret) return ret; +#ifdef CONFIG_MODULES ret = register_module_notifier(&trace_module_nb); if (ret) pr_warning("Failed to register trace events module notifier\n"); - +#endif return 0; } early_initcall(event_trace_memsetup); @@ -2633,6 +2547,8 @@ static __init void event_trace_self_tests(void) int ret; tr = top_trace_array(); + if (!tr) + return; pr_info("Running tests on trace events:\n"); @@ -2656,7 +2572,7 @@ static __init void event_trace_self_tests(void) continue; #endif - pr_info("Testing event %s: ", call->name); + pr_info("Testing event %s: ", ftrace_event_name(call)); /* * If an event is already enabled, someone is using |