diff options
Diffstat (limited to 'kernel/trace/trace_events.c')
-rw-r--r-- | kernel/trace/trace_events.c | 174 |
1 files changed, 130 insertions, 44 deletions
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index 92be9cb1d7d4..0356cae0cf74 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -40,6 +40,14 @@ static LIST_HEAD(ftrace_generic_fields); static LIST_HEAD(ftrace_common_fields); static bool eventdir_initialized; +static LIST_HEAD(module_strings); + +struct module_string { + struct list_head next; + struct module *module; + char *str; +}; + #define GFP_TRACE (GFP_KERNEL | __GFP_ZERO) static struct kmem_cache *field_cachep; @@ -168,6 +176,7 @@ static int trace_define_generic_fields(void) __generic_field(int, CPU, FILTER_CPU); __generic_field(int, cpu, FILTER_CPU); + __generic_field(int, common_cpu, FILTER_CPU); __generic_field(char *, COMM, FILTER_COMM); __generic_field(char *, comm, FILTER_COMM); @@ -399,7 +408,14 @@ static void test_event_printk(struct trace_event_call *call) a = strchr(fmt + i, '&'); if ((a && (a < r)) || test_field(r, call)) dereference_flags &= ~(1ULL << arg); + } else if ((r = strstr(fmt + i, "__get_dynamic_array(")) && + (!c || r < c)) { + dereference_flags &= ~(1ULL << arg); + } else if ((r = strstr(fmt + i, "__get_sockaddr(")) && + (!c || r < c)) { + dereference_flags &= ~(1ULL << arg); } + next_arg: i--; arg++; @@ -759,7 +775,9 @@ void trace_event_follow_fork(struct trace_array *tr, bool enable) static void event_filter_pid_sched_switch_probe_pre(void *data, bool preempt, - struct task_struct *prev, struct task_struct *next) + struct task_struct *prev, + struct task_struct *next, + unsigned int prev_state) { struct trace_array *tr = data; struct trace_pid_list *no_pid_list; @@ -783,7 +801,9 @@ event_filter_pid_sched_switch_probe_pre(void *data, bool preempt, static void event_filter_pid_sched_switch_probe_post(void *data, bool preempt, - struct task_struct *prev, struct task_struct *next) + struct task_struct *prev, + struct task_struct *next, + unsigned int prev_state) { struct trace_array *tr = data; struct trace_pid_list *no_pid_list; @@ -1705,9 +1725,9 @@ static LIST_HEAD(event_subsystems); static int subsystem_open(struct inode *inode, struct file *filp) { + struct trace_subsystem_dir *dir = NULL, *iter_dir; + struct trace_array *tr = NULL, *iter_tr; struct event_subsystem *system = NULL; - struct trace_subsystem_dir *dir = NULL; /* Initialize for gcc */ - struct trace_array *tr; int ret; if (tracing_is_disabled()) @@ -1716,10 +1736,12 @@ static int subsystem_open(struct inode *inode, struct file *filp) /* Make sure the system still exists */ mutex_lock(&event_mutex); mutex_lock(&trace_types_lock); - list_for_each_entry(tr, &ftrace_trace_arrays, list) { - list_for_each_entry(dir, &tr->systems, list) { - if (dir == inode->i_private) { + list_for_each_entry(iter_tr, &ftrace_trace_arrays, list) { + list_for_each_entry(iter_dir, &iter_tr->systems, list) { + if (iter_dir == inode->i_private) { /* Don't open systems with no events */ + tr = iter_tr; + dir = iter_dir; if (dir->nr_events) { __get_system_dir(dir); system = dir->subsystem; @@ -1735,9 +1757,6 @@ static int subsystem_open(struct inode *inode, struct file *filp) if (!system) return -ENODEV; - /* Some versions of gcc think dir can be uninitialized here */ - WARN_ON(!dir); - /* Still need to increment the ref count of the system */ if (trace_array_get(tr) < 0) { put_system(dir); @@ -2262,8 +2281,8 @@ static struct dentry * event_subsystem_dir(struct trace_array *tr, const char *name, struct trace_event_file *file, struct dentry *parent) { + struct event_subsystem *system, *iter; struct trace_subsystem_dir *dir; - struct event_subsystem *system; struct dentry *entry; /* First see if we did not already create this dir */ @@ -2277,13 +2296,13 @@ event_subsystem_dir(struct trace_array *tr, const char *name, } /* Now see if the system itself exists. */ - list_for_each_entry(system, &event_subsystems, list) { - if (strcmp(system->name, name) == 0) + system = NULL; + list_for_each_entry(iter, &event_subsystems, list) { + if (strcmp(iter->name, name) == 0) { + system = iter; break; + } } - /* Reset system variable when not found */ - if (&system->list == &event_subsystems) - system = NULL; dir = kmalloc(sizeof(*dir), GFP_KERNEL); if (!dir) @@ -2633,6 +2652,76 @@ static void update_event_printk(struct trace_event_call *call, } } +static void add_str_to_module(struct module *module, char *str) +{ + struct module_string *modstr; + + modstr = kmalloc(sizeof(*modstr), GFP_KERNEL); + + /* + * If we failed to allocate memory here, then we'll just + * let the str memory leak when the module is removed. + * If this fails to allocate, there's worse problems than + * a leaked string on module removal. + */ + if (WARN_ON_ONCE(!modstr)) + return; + + modstr->module = module; + modstr->str = str; + + list_add(&modstr->next, &module_strings); +} + +static void update_event_fields(struct trace_event_call *call, + struct trace_eval_map *map) +{ + struct ftrace_event_field *field; + struct list_head *head; + char *ptr; + char *str; + int len = strlen(map->eval_string); + + /* Dynamic events should never have field maps */ + if (WARN_ON_ONCE(call->flags & TRACE_EVENT_FL_DYNAMIC)) + return; + + head = trace_get_fields(call); + list_for_each_entry(field, head, link) { + ptr = strchr(field->type, '['); + if (!ptr) + continue; + ptr++; + + if (!isalpha(*ptr) && *ptr != '_') + continue; + + if (strncmp(map->eval_string, ptr, len) != 0) + continue; + + str = kstrdup(field->type, GFP_KERNEL); + if (WARN_ON_ONCE(!str)) + return; + ptr = str + (ptr - field->type); + ptr = eval_replace(ptr, map, len); + /* enum/sizeof string smaller than value */ + if (WARN_ON_ONCE(!ptr)) { + kfree(str); + continue; + } + + /* + * If the event is part of a module, then we need to free the string + * when the module is removed. Otherwise, it will stay allocated + * until a reboot. + */ + if (call->module) + add_str_to_module(call->module, str); + + field->type = str; + } +} + void trace_event_eval_update(struct trace_eval_map **map, int len) { struct trace_event_call *call, *p; @@ -2668,6 +2757,7 @@ void trace_event_eval_update(struct trace_eval_map **map, int len) first = false; } update_event_printk(call, map[i]); + update_event_fields(call, map[i]); } } } @@ -2758,6 +2848,7 @@ int trace_add_event_call(struct trace_event_call *call) mutex_unlock(&trace_types_lock); return ret; } +EXPORT_SYMBOL_GPL(trace_add_event_call); /* * Must be called under locking of trace_types_lock, event_mutex and @@ -2819,6 +2910,7 @@ int trace_remove_event_call(struct trace_event_call *call) return ret; } +EXPORT_SYMBOL_GPL(trace_remove_event_call); #define for_each_event(event, start, end) \ for (event = start; \ @@ -2853,6 +2945,7 @@ static void trace_module_add_events(struct module *mod) static void trace_module_remove_events(struct module *mod) { struct trace_event_call *call, *p; + struct module_string *modstr, *m; down_write(&trace_event_sem); list_for_each_entry_safe(call, p, &ftrace_events, list) { @@ -2861,6 +2954,14 @@ static void trace_module_remove_events(struct module *mod) if (call->module == mod) __trace_remove_event_call(call); } + /* Check for any strings allocade for this module */ + list_for_each_entry_safe(modstr, m, &module_strings, next) { + if (modstr->module != mod) + continue; + list_del(&modstr->next); + kfree(modstr->str); + kfree(modstr); + } up_write(&trace_event_sem); /* @@ -3446,12 +3547,10 @@ create_event_toplevel_files(struct dentry *parent, struct trace_array *tr) struct dentry *d_events; struct dentry *entry; - entry = tracefs_create_file("set_event", TRACE_MODE_WRITE, parent, - tr, &ftrace_set_event_fops); - if (!entry) { - pr_warn("Could not create tracefs 'set_event' entry\n"); + entry = trace_create_file("set_event", TRACE_MODE_WRITE, parent, + tr, &ftrace_set_event_fops); + if (!entry) return -ENOMEM; - } d_events = tracefs_create_dir("events", parent); if (!d_events) { @@ -3461,36 +3560,26 @@ create_event_toplevel_files(struct dentry *parent, struct trace_array *tr) entry = trace_create_file("enable", TRACE_MODE_WRITE, d_events, tr, &ftrace_tr_enable_fops); - if (!entry) { - pr_warn("Could not create tracefs 'enable' entry\n"); + if (!entry) return -ENOMEM; - } /* There are not as crucial, just warn if they are not created */ - entry = tracefs_create_file("set_event_pid", TRACE_MODE_WRITE, parent, - tr, &ftrace_set_event_pid_fops); - if (!entry) - pr_warn("Could not create tracefs 'set_event_pid' entry\n"); + trace_create_file("set_event_pid", TRACE_MODE_WRITE, parent, + tr, &ftrace_set_event_pid_fops); - entry = tracefs_create_file("set_event_notrace_pid", - TRACE_MODE_WRITE, parent, tr, - &ftrace_set_event_notrace_pid_fops); - if (!entry) - pr_warn("Could not create tracefs 'set_event_notrace_pid' entry\n"); + trace_create_file("set_event_notrace_pid", + TRACE_MODE_WRITE, parent, tr, + &ftrace_set_event_notrace_pid_fops); /* ring buffer internal formats */ - entry = trace_create_file("header_page", TRACE_MODE_READ, d_events, + trace_create_file("header_page", TRACE_MODE_READ, d_events, ring_buffer_print_page_header, &ftrace_show_header_fops); - if (!entry) - pr_warn("Could not create tracefs 'header_page' entry\n"); - entry = trace_create_file("header_event", TRACE_MODE_READ, d_events, + trace_create_file("header_event", TRACE_MODE_READ, d_events, ring_buffer_print_entry_header, &ftrace_show_header_fops); - if (!entry) - pr_warn("Could not create tracefs 'header_event' entry\n"); tr->event_dir = d_events; @@ -3696,17 +3785,14 @@ static __init int event_trace_init_fields(void) __init int event_trace_init(void) { struct trace_array *tr; - struct dentry *entry; int ret; tr = top_trace_array(); if (!tr) return -ENODEV; - entry = tracefs_create_file("available_events", TRACE_MODE_READ, - NULL, tr, &ftrace_avail_fops); - if (!entry) - pr_warn("Could not create tracefs 'available_events' entry\n"); + trace_create_file("available_events", TRACE_MODE_READ, + NULL, tr, &ftrace_avail_fops); ret = early_event_add_tracer(NULL, tr); if (ret) |