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Diffstat (limited to 'kernel/trace/trace_events.c')
-rw-r--r--kernel/trace/trace_events.c834
1 files changed, 635 insertions, 199 deletions
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 52f75c36bbca..120531268abf 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -82,7 +82,7 @@ static int system_refcount_dec(struct event_subsystem *system)
}
static struct ftrace_event_field *
-__find_event_field(struct list_head *head, char *name)
+__find_event_field(struct list_head *head, const char *name)
{
struct ftrace_event_field *field;
@@ -114,7 +114,8 @@ trace_find_event_field(struct trace_event_call *call, char *name)
static int __trace_define_field(struct list_head *head, const char *type,
const char *name, int offset, int size,
- int is_signed, int filter_type, int len)
+ int is_signed, int filter_type, int len,
+ int need_test)
{
struct ftrace_event_field *field;
@@ -133,6 +134,7 @@ static int __trace_define_field(struct list_head *head, const char *type,
field->offset = offset;
field->size = size;
field->is_signed = is_signed;
+ field->needs_test = need_test;
field->len = len;
list_add(&field->link, head);
@@ -151,13 +153,13 @@ int trace_define_field(struct trace_event_call *call, const char *type,
head = trace_get_fields(call);
return __trace_define_field(head, type, name, offset, size,
- is_signed, filter_type, 0);
+ is_signed, filter_type, 0, 0);
}
EXPORT_SYMBOL_GPL(trace_define_field);
static int trace_define_field_ext(struct trace_event_call *call, const char *type,
const char *name, int offset, int size, int is_signed,
- int filter_type, int len)
+ int filter_type, int len, int need_test)
{
struct list_head *head;
@@ -166,13 +168,13 @@ static int trace_define_field_ext(struct trace_event_call *call, const char *typ
head = trace_get_fields(call);
return __trace_define_field(head, type, name, offset, size,
- is_signed, filter_type, len);
+ is_signed, filter_type, len, need_test);
}
#define __generic_field(type, item, filter_type) \
ret = __trace_define_field(&ftrace_generic_fields, #type, \
#item, 0, 0, is_signed_type(type), \
- filter_type, 0); \
+ filter_type, 0, 0); \
if (ret) \
return ret;
@@ -181,7 +183,8 @@ static int trace_define_field_ext(struct trace_event_call *call, const char *typ
"common_" #item, \
offsetof(typeof(ent), item), \
sizeof(ent.item), \
- is_signed_type(type), FILTER_OTHER, 0); \
+ is_signed_type(type), FILTER_OTHER, \
+ 0, 0); \
if (ret) \
return ret;
@@ -244,19 +247,16 @@ int trace_event_get_offsets(struct trace_event_call *call)
return tail->offset + tail->size;
}
-/*
- * Check if the referenced field is an array and return true,
- * as arrays are OK to dereference.
- */
-static bool test_field(const char *fmt, struct trace_event_call *call)
+
+static struct trace_event_fields *find_event_field(const char *fmt,
+ struct trace_event_call *call)
{
struct trace_event_fields *field = call->class->fields_array;
- const char *array_descriptor;
const char *p = fmt;
int len;
if (!(len = str_has_prefix(fmt, "REC->")))
- return false;
+ return NULL;
fmt += len;
for (p = fmt; *p; p++) {
if (!isalnum(*p) && *p != '_')
@@ -265,16 +265,155 @@ static bool test_field(const char *fmt, struct trace_event_call *call)
len = p - fmt;
for (; field->type; field++) {
- if (strncmp(field->name, fmt, len) ||
- field->name[len])
+ if (strncmp(field->name, fmt, len) || field->name[len])
continue;
- array_descriptor = strchr(field->type, '[');
- /* This is an array and is OK to dereference. */
- return array_descriptor != NULL;
+
+ return field;
+ }
+ return NULL;
+}
+
+/*
+ * Check if the referenced field is an array and return true,
+ * as arrays are OK to dereference.
+ */
+static bool test_field(const char *fmt, struct trace_event_call *call)
+{
+ struct trace_event_fields *field;
+
+ field = find_event_field(fmt, call);
+ if (!field)
+ return false;
+
+ /* This is an array and is OK to dereference. */
+ return strchr(field->type, '[') != NULL;
+}
+
+/* Look for a string within an argument */
+static bool find_print_string(const char *arg, const char *str, const char *end)
+{
+ const char *r;
+
+ r = strstr(arg, str);
+ return r && r < end;
+}
+
+/* Return true if the argument pointer is safe */
+static bool process_pointer(const char *fmt, int len, struct trace_event_call *call)
+{
+ const char *r, *e, *a;
+
+ e = fmt + len;
+
+ /* Find the REC-> in the argument */
+ r = strstr(fmt, "REC->");
+ if (r && r < e) {
+ /*
+ * Addresses of events on the buffer, or an array on the buffer is
+ * OK to dereference. There's ways to fool this, but
+ * this is to catch common mistakes, not malicious code.
+ */
+ a = strchr(fmt, '&');
+ if ((a && (a < r)) || test_field(r, call))
+ return true;
+ } else if (find_print_string(fmt, "__get_dynamic_array(", e)) {
+ return true;
+ } else if (find_print_string(fmt, "__get_rel_dynamic_array(", e)) {
+ return true;
+ } else if (find_print_string(fmt, "__get_dynamic_array_len(", e)) {
+ return true;
+ } else if (find_print_string(fmt, "__get_rel_dynamic_array_len(", e)) {
+ return true;
+ } else if (find_print_string(fmt, "__get_sockaddr(", e)) {
+ return true;
+ } else if (find_print_string(fmt, "__get_rel_sockaddr(", e)) {
+ return true;
}
return false;
}
+/* Return true if the string is safe */
+static bool process_string(const char *fmt, int len, struct trace_event_call *call)
+{
+ struct trace_event_fields *field;
+ const char *r, *e, *s;
+
+ e = fmt + len;
+
+ /*
+ * There are several helper functions that return strings.
+ * If the argument contains a function, then assume its field is valid.
+ * It is considered that the argument has a function if it has:
+ * alphanumeric or '_' before a parenthesis.
+ */
+ s = fmt;
+ do {
+ r = strstr(s, "(");
+ if (!r || r >= e)
+ break;
+ for (int i = 1; r - i >= s; i++) {
+ char ch = *(r - i);
+ if (isspace(ch))
+ continue;
+ if (isalnum(ch) || ch == '_')
+ return true;
+ /* Anything else, this isn't a function */
+ break;
+ }
+ /* A function could be wrapped in parethesis, try the next one */
+ s = r + 1;
+ } while (s < e);
+
+ /*
+ * Check for arrays. If the argument has: foo[REC->val]
+ * then it is very likely that foo is an array of strings
+ * that are safe to use.
+ */
+ r = strstr(s, "[");
+ if (r && r < e) {
+ r = strstr(r, "REC->");
+ if (r && r < e)
+ return true;
+ }
+
+ /*
+ * If there's any strings in the argument consider this arg OK as it
+ * could be: REC->field ? "foo" : "bar" and we don't want to get into
+ * verifying that logic here.
+ */
+ if (find_print_string(fmt, "\"", e))
+ return true;
+
+ /* Dereferenced strings are also valid like any other pointer */
+ if (process_pointer(fmt, len, call))
+ return true;
+
+ /* Make sure the field is found */
+ field = find_event_field(fmt, call);
+ if (!field)
+ return false;
+
+ /* Test this field's string before printing the event */
+ call->flags |= TRACE_EVENT_FL_TEST_STR;
+ field->needs_test = 1;
+
+ return true;
+}
+
+static void handle_dereference_arg(const char *arg_str, u64 string_flags, int len,
+ u64 *dereference_flags, int arg,
+ struct trace_event_call *call)
+{
+ if (string_flags & (1ULL << arg)) {
+ if (process_string(arg_str, len, call))
+ *dereference_flags &= ~(1ULL << arg);
+ } else if (process_pointer(arg_str, len, call))
+ *dereference_flags &= ~(1ULL << arg);
+ else
+ pr_warn("TRACE EVENT ERROR: Bad dereference argument: '%.*s'\n",
+ len, arg_str);
+}
+
/*
* Examine the print fmt of the event looking for unsafe dereference
* pointers using %p* that could be recorded in the trace event and
@@ -284,13 +423,14 @@ static bool test_field(const char *fmt, struct trace_event_call *call)
static void test_event_printk(struct trace_event_call *call)
{
u64 dereference_flags = 0;
+ u64 string_flags = 0;
bool first = true;
- const char *fmt, *c, *r, *a;
+ const char *fmt;
int parens = 0;
char in_quote = 0;
int start_arg = 0;
int arg = 0;
- int i;
+ int i, e;
fmt = call->print_fmt;
@@ -344,6 +484,7 @@ static void test_event_printk(struct trace_event_call *call)
case '%':
continue;
case 'p':
+ do_pointer:
/* Find dereferencing fields */
switch (fmt[i + 1]) {
case 'B': case 'R': case 'r':
@@ -372,10 +513,24 @@ static void test_event_printk(struct trace_event_call *call)
continue;
if (fmt[i + j] == '*') {
star = true;
+ /* Handle %*pbl case */
+ if (!j && fmt[i + 1] == 'p') {
+ arg++;
+ i++;
+ goto do_pointer;
+ }
continue;
}
- if ((fmt[i + j] == 's') && star)
- arg++;
+ if ((fmt[i + j] == 's')) {
+ if (star)
+ arg++;
+ if (WARN_ONCE(arg == 63,
+ "Too many args for event: %s",
+ trace_event_name(call)))
+ return;
+ dereference_flags |= 1ULL << arg;
+ string_flags |= 1ULL << arg;
+ }
break;
}
break;
@@ -403,42 +558,43 @@ static void test_event_printk(struct trace_event_call *call)
case ',':
if (in_quote || parens)
continue;
+ e = i;
i++;
while (isspace(fmt[i]))
i++;
- start_arg = i;
- if (!(dereference_flags & (1ULL << arg)))
- goto next_arg;
- /* Find the REC-> in the argument */
- c = strchr(fmt + i, ',');
- r = strstr(fmt + i, "REC->");
- if (r && (!c || r < c)) {
- /*
- * Addresses of events on the buffer,
- * or an array on the buffer is
- * OK to dereference.
- * There's ways to fool this, but
- * this is to catch common mistakes,
- * not malicious code.
- */
- 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);
+ /*
+ * If start_arg is zero, then this is the start of the
+ * first argument. The processing of the argument happens
+ * when the end of the argument is found, as it needs to
+ * handle paranthesis and such.
+ */
+ if (!start_arg) {
+ start_arg = i;
+ /* Balance out the i++ in the for loop */
+ i--;
+ continue;
}
- next_arg:
- i--;
+ if (dereference_flags & (1ULL << arg)) {
+ handle_dereference_arg(fmt + start_arg, string_flags,
+ e - start_arg,
+ &dereference_flags, arg, call);
+ }
+
+ start_arg = i;
arg++;
+ /* Balance out the i++ in the for loop */
+ i--;
}
}
+ if (dereference_flags & (1ULL << arg)) {
+ handle_dereference_arg(fmt + start_arg, string_flags,
+ i - start_arg,
+ &dereference_flags, arg, call);
+ }
+
/*
* If you triggered the below warning, the trace event reported
* uses an unsafe dereference pointer %p*. As the data stored
@@ -476,7 +632,6 @@ EXPORT_SYMBOL_GPL(trace_event_raw_init);
bool trace_event_ignore_this_pid(struct trace_event_file *trace_file)
{
struct trace_array *tr = trace_file->tr;
- struct trace_array_cpu *data;
struct trace_pid_list *no_pid_list;
struct trace_pid_list *pid_list;
@@ -486,9 +641,11 @@ bool trace_event_ignore_this_pid(struct trace_event_file *trace_file)
if (!pid_list && !no_pid_list)
return false;
- data = this_cpu_ptr(tr->array_buffer.data);
-
- return data->ignore_pid;
+ /*
+ * This is recorded at every sched_switch for this task.
+ * Thus, even if the task migrates the ignore value will be the same.
+ */
+ return this_cpu_read(tr->array_buffer.data->ignore_pid) != 0;
}
EXPORT_SYMBOL_GPL(trace_event_ignore_this_pid);
@@ -651,7 +808,9 @@ static int __ftrace_event_enable_disable(struct trace_event_file *file,
clear_bit(EVENT_FILE_FL_RECORDED_TGID_BIT, &file->flags);
}
- call->class->reg(call, TRACE_REG_UNREGISTER, file);
+ ret = call->class->reg(call, TRACE_REG_UNREGISTER, file);
+
+ WARN_ON_ONCE(ret);
}
/* If in SOFT_MODE, just set the SOFT_DISABLE_BIT, else clear it */
if (file->flags & EVENT_FILE_FL_SOFT_MODE)
@@ -730,6 +889,120 @@ static int ftrace_event_enable_disable(struct trace_event_file *file,
return __ftrace_event_enable_disable(file, enable, 0);
}
+#ifdef CONFIG_MODULES
+struct event_mod_load {
+ struct list_head list;
+ char *module;
+ char *match;
+ char *system;
+ char *event;
+};
+
+static void free_event_mod(struct event_mod_load *event_mod)
+{
+ list_del(&event_mod->list);
+ kfree(event_mod->module);
+ kfree(event_mod->match);
+ kfree(event_mod->system);
+ kfree(event_mod->event);
+ kfree(event_mod);
+}
+
+static void clear_mod_events(struct trace_array *tr)
+{
+ struct event_mod_load *event_mod, *n;
+
+ list_for_each_entry_safe(event_mod, n, &tr->mod_events, list) {
+ free_event_mod(event_mod);
+ }
+}
+
+static int remove_cache_mod(struct trace_array *tr, const char *mod,
+ const char *match, const char *system, const char *event)
+{
+ struct event_mod_load *event_mod, *n;
+ int ret = -EINVAL;
+
+ list_for_each_entry_safe(event_mod, n, &tr->mod_events, list) {
+ if (strcmp(event_mod->module, mod) != 0)
+ continue;
+
+ if (match && strcmp(event_mod->match, match) != 0)
+ continue;
+
+ if (system &&
+ (!event_mod->system || strcmp(event_mod->system, system) != 0))
+ continue;
+
+ if (event &&
+ (!event_mod->event || strcmp(event_mod->event, event) != 0))
+ continue;
+
+ free_event_mod(event_mod);
+ ret = 0;
+ }
+
+ return ret;
+}
+
+static int cache_mod(struct trace_array *tr, const char *mod, int set,
+ const char *match, const char *system, const char *event)
+{
+ struct event_mod_load *event_mod;
+
+ /* If the module exists, then this just failed to find an event */
+ if (module_exists(mod))
+ return -EINVAL;
+
+ /* See if this is to remove a cached filter */
+ if (!set)
+ return remove_cache_mod(tr, mod, match, system, event);
+
+ event_mod = kzalloc(sizeof(*event_mod), GFP_KERNEL);
+ if (!event_mod)
+ return -ENOMEM;
+
+ INIT_LIST_HEAD(&event_mod->list);
+ event_mod->module = kstrdup(mod, GFP_KERNEL);
+ if (!event_mod->module)
+ goto out_free;
+
+ if (match) {
+ event_mod->match = kstrdup(match, GFP_KERNEL);
+ if (!event_mod->match)
+ goto out_free;
+ }
+
+ if (system) {
+ event_mod->system = kstrdup(system, GFP_KERNEL);
+ if (!event_mod->system)
+ goto out_free;
+ }
+
+ if (event) {
+ event_mod->event = kstrdup(event, GFP_KERNEL);
+ if (!event_mod->event)
+ goto out_free;
+ }
+
+ list_add(&event_mod->list, &tr->mod_events);
+
+ return 0;
+
+ out_free:
+ free_event_mod(event_mod);
+
+ return -ENOMEM;
+}
+#else /* CONFIG_MODULES */
+static inline void clear_mod_events(struct trace_array *tr) { }
+static int cache_mod(struct trace_array *tr, const char *mod, int set,
+ const char *match, const char *system, const char *event)
+{
+ return -EINVAL;
+}
+#endif
+
static void ftrace_clear_events(struct trace_array *tr)
{
struct trace_event_file *file;
@@ -738,6 +1011,7 @@ static void ftrace_clear_events(struct trace_array *tr)
list_for_each_entry(file, &tr->events, list) {
ftrace_event_enable_disable(file, 0);
}
+ clear_mod_events(tr);
mutex_unlock(&event_mutex);
}
@@ -992,18 +1266,18 @@ static void remove_subsystem(struct trace_subsystem_dir *dir)
void event_file_get(struct trace_event_file *file)
{
- atomic_inc(&file->ref);
+ refcount_inc(&file->ref);
}
void event_file_put(struct trace_event_file *file)
{
- if (WARN_ON_ONCE(!atomic_read(&file->ref))) {
+ if (WARN_ON_ONCE(!refcount_read(&file->ref))) {
if (file->flags & EVENT_FILE_FL_FREED)
kmem_cache_free(file_cachep, file);
return;
}
- if (atomic_dec_and_test(&file->ref)) {
+ if (refcount_dec_and_test(&file->ref)) {
/* Count should only go to zero when it is freed */
if (WARN_ON_ONCE(!(file->flags & EVENT_FILE_FL_FREED)))
return;
@@ -1026,17 +1300,36 @@ static void remove_event_file_dir(struct trace_event_file *file)
*/
static int
__ftrace_set_clr_event_nolock(struct trace_array *tr, const char *match,
- const char *sub, const char *event, int set)
+ const char *sub, const char *event, int set,
+ const char *mod)
{
struct trace_event_file *file;
struct trace_event_call *call;
+ char *module __free(kfree) = NULL;
const char *name;
int ret = -EINVAL;
int eret = 0;
+ if (mod) {
+ char *p;
+
+ module = kstrdup(mod, GFP_KERNEL);
+ if (!module)
+ return -ENOMEM;
+
+ /* Replace all '-' with '_' as that's what modules do */
+ for (p = strchr(module, '-'); p; p = strchr(p + 1, '-'))
+ *p = '_';
+ }
+
list_for_each_entry(file, &tr->events, list) {
call = file->event_call;
+
+ /* If a module is specified, skip events that are not that module */
+ if (module && (!call->module || strcmp(module_name(call->module), module)))
+ continue;
+
name = trace_event_name(call);
if (!name || !call->class || !call->class->reg)
@@ -1069,16 +1362,24 @@ __ftrace_set_clr_event_nolock(struct trace_array *tr, const char *match,
ret = eret;
}
+ /*
+ * If this is a module setting and nothing was found,
+ * check if the module was loaded. If it wasn't cache it.
+ */
+ if (module && ret == -EINVAL && !eret)
+ ret = cache_mod(tr, module, set, match, sub, event);
+
return ret;
}
static int __ftrace_set_clr_event(struct trace_array *tr, const char *match,
- const char *sub, const char *event, int set)
+ const char *sub, const char *event, int set,
+ const char *mod)
{
int ret;
mutex_lock(&event_mutex);
- ret = __ftrace_set_clr_event_nolock(tr, match, sub, event, set);
+ ret = __ftrace_set_clr_event_nolock(tr, match, sub, event, set, mod);
mutex_unlock(&event_mutex);
return ret;
@@ -1086,11 +1387,20 @@ static int __ftrace_set_clr_event(struct trace_array *tr, const char *match,
int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set)
{
- char *event = NULL, *sub = NULL, *match;
+ char *event = NULL, *sub = NULL, *match, *mod;
int ret;
if (!tr)
return -ENOENT;
+
+ /* Modules events can be appened with :mod:<module> */
+ mod = strstr(buf, ":mod:");
+ if (mod) {
+ *mod = '\0';
+ /* move to the module name */
+ mod += 5;
+ }
+
/*
* The buf format can be <subsystem>:<event-name>
* *:<event-name> means any event by that name.
@@ -1113,9 +1423,13 @@ int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set)
sub = NULL;
if (!strlen(event) || strcmp(event, "*") == 0)
event = NULL;
+ } else if (mod) {
+ /* Allow wildcard for no length or star */
+ if (!strlen(match) || strcmp(match, "*") == 0)
+ match = NULL;
}
- ret = __ftrace_set_clr_event(tr, match, sub, event, set);
+ ret = __ftrace_set_clr_event(tr, match, sub, event, set, mod);
/* Put back the colon to allow this to be called again */
if (buf)
@@ -1143,7 +1457,7 @@ int trace_set_clr_event(const char *system, const char *event, int set)
if (!tr)
return -ENODEV;
- return __ftrace_set_clr_event(tr, NULL, system, event, set);
+ return __ftrace_set_clr_event(tr, NULL, system, event, set, NULL);
}
EXPORT_SYMBOL_GPL(trace_set_clr_event);
@@ -1169,7 +1483,7 @@ int trace_array_set_clr_event(struct trace_array *tr, const char *system,
return -ENOENT;
set = (enable == true) ? 1 : 0;
- return __ftrace_set_clr_event(tr, NULL, system, event, set);
+ return __ftrace_set_clr_event(tr, NULL, system, event, set, NULL);
}
EXPORT_SYMBOL_GPL(trace_array_set_clr_event);
@@ -1256,37 +1570,78 @@ static void *t_start(struct seq_file *m, loff_t *pos)
return file;
}
+enum set_event_iter_type {
+ SET_EVENT_FILE,
+ SET_EVENT_MOD,
+};
+
+struct set_event_iter {
+ enum set_event_iter_type type;
+ union {
+ struct trace_event_file *file;
+ struct event_mod_load *event_mod;
+ };
+};
+
static void *
s_next(struct seq_file *m, void *v, loff_t *pos)
{
- struct trace_event_file *file = v;
+ struct set_event_iter *iter = v;
+ struct trace_event_file *file;
struct trace_array *tr = m->private;
(*pos)++;
- list_for_each_entry_continue(file, &tr->events, list) {
- if (file->flags & EVENT_FILE_FL_ENABLED)
- return file;
+ if (iter->type == SET_EVENT_FILE) {
+ file = iter->file;
+ list_for_each_entry_continue(file, &tr->events, list) {
+ if (file->flags & EVENT_FILE_FL_ENABLED) {
+ iter->file = file;
+ return iter;
+ }
+ }
+#ifdef CONFIG_MODULES
+ iter->type = SET_EVENT_MOD;
+ iter->event_mod = list_entry(&tr->mod_events, struct event_mod_load, list);
+#endif
}
+#ifdef CONFIG_MODULES
+ list_for_each_entry_continue(iter->event_mod, &tr->mod_events, list)
+ return iter;
+#endif
+
+ /*
+ * The iter is allocated in s_start() and passed via the 'v'
+ * parameter. To stop the iterator, NULL must be returned. But
+ * the return value is what the 'v' parameter in s_stop() receives
+ * and frees. Free iter here as it will no longer be used.
+ */
+ kfree(iter);
return NULL;
}
static void *s_start(struct seq_file *m, loff_t *pos)
{
- struct trace_event_file *file;
struct trace_array *tr = m->private;
+ struct set_event_iter *iter;
loff_t l;
+ iter = kzalloc(sizeof(*iter), GFP_KERNEL);
+ if (!iter)
+ return NULL;
+
mutex_lock(&event_mutex);
- file = list_entry(&tr->events, struct trace_event_file, list);
+ iter->type = SET_EVENT_FILE;
+ iter->file = list_entry(&tr->events, struct trace_event_file, list);
+
for (l = 0; l <= *pos; ) {
- file = s_next(m, file, &l);
- if (!file)
+ iter = s_next(m, iter, &l);
+ if (!iter)
break;
}
- return file;
+ return iter;
}
static int t_show(struct seq_file *m, void *v)
@@ -1306,6 +1661,45 @@ static void t_stop(struct seq_file *m, void *p)
mutex_unlock(&event_mutex);
}
+#ifdef CONFIG_MODULES
+static int s_show(struct seq_file *m, void *v)
+{
+ struct set_event_iter *iter = v;
+ const char *system;
+ const char *event;
+
+ if (iter->type == SET_EVENT_FILE)
+ return t_show(m, iter->file);
+
+ /* When match is set, system and event are not */
+ if (iter->event_mod->match) {
+ seq_printf(m, "%s:mod:%s\n", iter->event_mod->match,
+ iter->event_mod->module);
+ return 0;
+ }
+
+ system = iter->event_mod->system ? : "*";
+ event = iter->event_mod->event ? : "*";
+
+ seq_printf(m, "%s:%s:mod:%s\n", system, event, iter->event_mod->module);
+
+ return 0;
+}
+#else /* CONFIG_MODULES */
+static int s_show(struct seq_file *m, void *v)
+{
+ struct set_event_iter *iter = v;
+
+ return t_show(m, iter->file);
+}
+#endif
+
+static void s_stop(struct seq_file *m, void *v)
+{
+ kfree(v);
+ t_stop(m, NULL);
+}
+
static void *
__next(struct seq_file *m, void *v, loff_t *pos, int type)
{
@@ -1386,12 +1780,12 @@ event_enable_read(struct file *filp, char __user *ubuf, size_t cnt,
char buf[4] = "0";
mutex_lock(&event_mutex);
- file = event_file_data(filp);
+ file = event_file_file(filp);
if (likely(file))
flags = file->flags;
mutex_unlock(&event_mutex);
- if (!file || flags & EVENT_FILE_FL_FREED)
+ if (!file)
return -ENODEV;
if (flags & EVENT_FILE_FL_ENABLED &&
@@ -1419,21 +1813,20 @@ event_enable_write(struct file *filp, const char __user *ubuf, size_t cnt,
if (ret)
return ret;
+ guard(mutex)(&event_mutex);
+
switch (val) {
case 0:
case 1:
- ret = -ENODEV;
- mutex_lock(&event_mutex);
- file = event_file_data(filp);
- if (likely(file && !(file->flags & EVENT_FILE_FL_FREED))) {
- ret = tracing_update_buffers(file->tr);
- if (ret < 0) {
- mutex_unlock(&event_mutex);
- return ret;
- }
- ret = ftrace_event_enable_disable(file, val);
- }
- mutex_unlock(&event_mutex);
+ file = event_file_file(filp);
+ if (!file)
+ return -ENODEV;
+ ret = tracing_update_buffers(file->tr);
+ if (ret < 0)
+ return ret;
+ ret = ftrace_event_enable_disable(file, val);
+ if (ret < 0)
+ return ret;
break;
default:
@@ -1442,31 +1835,31 @@ event_enable_write(struct file *filp, const char __user *ubuf, size_t cnt,
*ppos += cnt;
- return ret ? ret : cnt;
+ return cnt;
}
-static ssize_t
-system_enable_read(struct file *filp, char __user *ubuf, size_t cnt,
- loff_t *ppos)
+/*
+ * Returns:
+ * 0 : no events exist?
+ * 1 : all events are disabled
+ * 2 : all events are enabled
+ * 3 : some events are enabled and some are enabled
+ */
+int trace_events_enabled(struct trace_array *tr, const char *system)
{
- const char set_to_char[4] = { '?', '0', '1', 'X' };
- struct trace_subsystem_dir *dir = filp->private_data;
- struct event_subsystem *system = dir->subsystem;
struct trace_event_call *call;
struct trace_event_file *file;
- struct trace_array *tr = dir->tr;
- char buf[2];
int set = 0;
- int ret;
- mutex_lock(&event_mutex);
+ guard(mutex)(&event_mutex);
+
list_for_each_entry(file, &tr->events, list) {
call = file->event_call;
if ((call->flags & TRACE_EVENT_FL_IGNORE_ENABLE) ||
!trace_event_name(call) || !call->class || !call->class->reg)
continue;
- if (system && strcmp(call->class->system, system->name) != 0)
+ if (system && strcmp(call->class->system, system) != 0)
continue;
/*
@@ -1482,7 +1875,23 @@ system_enable_read(struct file *filp, char __user *ubuf, size_t cnt,
if (set == 3)
break;
}
- mutex_unlock(&event_mutex);
+
+ return set;
+}
+
+static ssize_t
+system_enable_read(struct file *filp, char __user *ubuf, size_t cnt,
+ loff_t *ppos)
+{
+ const char set_to_char[4] = { '?', '0', '1', 'X' };
+ struct trace_subsystem_dir *dir = filp->private_data;
+ struct event_subsystem *system = dir->subsystem;
+ struct trace_array *tr = dir->tr;
+ char buf[2];
+ int set;
+ int ret;
+
+ set = trace_events_enabled(tr, system ? system->name : NULL);
buf[0] = set_to_char[set];
buf[1] = '\n';
@@ -1520,7 +1929,7 @@ system_enable_write(struct file *filp, const char __user *ubuf, size_t cnt,
if (system)
name = system->name;
- ret = __ftrace_set_clr_event(dir->tr, NULL, name, NULL, val);
+ ret = __ftrace_set_clr_event(dir->tr, NULL, name, NULL, val, NULL);
if (ret)
goto out;
@@ -1540,7 +1949,8 @@ enum {
static void *f_next(struct seq_file *m, void *v, loff_t *pos)
{
- struct trace_event_call *call = event_file_data(m->private);
+ struct trace_event_file *file = event_file_data(m->private);
+ struct trace_event_call *call = file->event_call;
struct list_head *common_head = &ftrace_common_fields;
struct list_head *head = trace_get_fields(call);
struct list_head *node = v;
@@ -1572,7 +1982,8 @@ static void *f_next(struct seq_file *m, void *v, loff_t *pos)
static int f_show(struct seq_file *m, void *v)
{
- struct trace_event_call *call = event_file_data(m->private);
+ struct trace_event_file *file = event_file_data(m->private);
+ struct trace_event_call *call = file->event_call;
struct ftrace_event_field *field;
const char *array_descriptor;
@@ -1627,12 +2038,14 @@ static int f_show(struct seq_file *m, void *v)
static void *f_start(struct seq_file *m, loff_t *pos)
{
+ struct trace_event_file *file;
void *p = (void *)FORMAT_HEADER;
loff_t l = 0;
/* ->stop() is called even if ->start() fails */
mutex_lock(&event_mutex);
- if (!event_file_data(m->private))
+ file = event_file_file(m->private);
+ if (!file)
return ERR_PTR(-ENODEV);
while (l < *pos && p)
@@ -1706,8 +2119,8 @@ event_filter_read(struct file *filp, char __user *ubuf, size_t cnt,
trace_seq_init(s);
mutex_lock(&event_mutex);
- file = event_file_data(filp);
- if (file && !(file->flags & EVENT_FILE_FL_FREED))
+ file = event_file_file(filp);
+ if (file)
print_event_filter(file, s);
mutex_unlock(&event_mutex);
@@ -1736,9 +2149,13 @@ event_filter_write(struct file *filp, const char __user *ubuf, size_t cnt,
return PTR_ERR(buf);
mutex_lock(&event_mutex);
- file = event_file_data(filp);
- if (file)
- err = apply_event_filter(file, buf);
+ file = event_file_file(filp);
+ if (file) {
+ if (file->flags & EVENT_FILE_FL_FREED)
+ err = -ENODEV;
+ else
+ err = apply_event_filter(file, buf);
+ }
mutex_unlock(&event_mutex);
kfree(buf);
@@ -2010,7 +2427,7 @@ event_pid_write(struct file *filp, const char __user *ubuf,
if (ret < 0)
return ret;
- mutex_lock(&event_mutex);
+ guard(mutex)(&event_mutex);
if (type == TRACE_PIDS) {
filtered_pids = rcu_dereference_protected(tr->filtered_pids,
@@ -2026,7 +2443,7 @@ event_pid_write(struct file *filp, const char __user *ubuf,
ret = trace_pid_write(filtered_pids, &pid_list, ubuf, cnt);
if (ret < 0)
- goto out;
+ return ret;
if (type == TRACE_PIDS)
rcu_assign_pointer(tr->filtered_pids, pid_list);
@@ -2051,11 +2468,7 @@ event_pid_write(struct file *filp, const char __user *ubuf,
*/
on_each_cpu(ignore_task_cpu, tr, 1);
- out:
- mutex_unlock(&event_mutex);
-
- if (ret > 0)
- *ppos += ret;
+ *ppos += ret;
return ret;
}
@@ -2090,8 +2503,8 @@ static const struct seq_operations show_event_seq_ops = {
static const struct seq_operations show_set_event_seq_ops = {
.start = s_start,
.next = s_next,
- .show = t_show,
- .stop = t_stop,
+ .show = s_show,
+ .stop = s_stop,
};
static const struct seq_operations show_set_pid_seq_ops = {
@@ -2463,7 +2876,7 @@ event_define_fields(struct trace_event_call *call)
ret = trace_define_field_ext(call, field->type, field->name,
offset, field->size,
field->is_signed, field->filter_type,
- field->len);
+ field->len, field->needs_test);
if (WARN_ON_ONCE(ret)) {
pr_err("error code is %d\n", ret);
break;
@@ -2485,7 +2898,6 @@ static int event_callback(const char *name, umode_t *mode, void **data,
if (strcmp(name, "format") == 0) {
*mode = TRACE_MODE_READ;
*fops = &ftrace_event_format_fops;
- *data = call;
return 1;
}
@@ -2552,6 +2964,14 @@ static int event_callback(const char *name, umode_t *mode, void **data,
return 0;
}
+/* The file is incremented on creation and freeing the enable file decrements it */
+static void event_release(const char *name, void *data)
+{
+ struct trace_event_file *file = data;
+
+ event_file_put(file);
+}
+
static int
event_create_dir(struct eventfs_inode *parent, struct trace_event_file *file)
{
@@ -2566,6 +2986,7 @@ event_create_dir(struct eventfs_inode *parent, struct trace_event_file *file)
{
.name = "enable",
.callback = event_callback,
+ .release = event_release,
},
{
.name = "filter",
@@ -2634,6 +3055,9 @@ event_create_dir(struct eventfs_inode *parent, struct trace_event_file *file)
return ret;
}
+ /* Gets decremented on freeing of the "enable" file */
+ event_file_get(file);
+
return 0;
}
@@ -2953,6 +3377,20 @@ static bool event_in_systems(struct trace_event_call *call,
return !*p || isspace(*p) || *p == ',';
}
+#ifdef CONFIG_HIST_TRIGGERS
+/*
+ * Wake up waiter on the hist_poll_wq from irq_work because the hist trigger
+ * may happen in any context.
+ */
+static void hist_poll_event_irq_work(struct irq_work *work)
+{
+ wake_up_all(&hist_poll_wq);
+}
+
+DEFINE_IRQ_WORK(hist_poll_work, hist_poll_event_irq_work);
+DECLARE_WAIT_QUEUE_HEAD(hist_poll_wq);
+#endif
+
static struct trace_event_file *
trace_create_new_event(struct trace_event_call *call,
struct trace_array *tr)
@@ -2984,7 +3422,7 @@ trace_create_new_event(struct trace_event_call *call,
atomic_set(&file->tm_ref, 0);
INIT_LIST_HEAD(&file->triggers);
list_add(&file->list, &tr->events);
- event_file_get(file);
+ refcount_set(&file->ref, 1);
return file;
}
@@ -3111,13 +3549,13 @@ int trace_add_event_call(struct trace_event_call *call)
int ret;
lockdep_assert_held(&event_mutex);
- mutex_lock(&trace_types_lock);
+ guard(mutex)(&trace_types_lock);
ret = __register_event(call, NULL);
- if (ret >= 0)
- __add_event_to_tracers(call);
+ if (ret < 0)
+ return ret;
- mutex_unlock(&trace_types_lock);
+ __add_event_to_tracers(call);
return ret;
}
EXPORT_SYMBOL_GPL(trace_add_event_call);
@@ -3130,8 +3568,6 @@ static void __trace_remove_event_call(struct trace_event_call *call)
{
event_remove(call);
trace_destroy_fields(call);
- free_event_filter(call->filter);
- call->filter = NULL;
}
static int probe_remove_event_call(struct trace_event_call *call)
@@ -3199,6 +3635,28 @@ EXPORT_SYMBOL_GPL(trace_remove_event_call);
event++)
#ifdef CONFIG_MODULES
+static void update_mod_cache(struct trace_array *tr, struct module *mod)
+{
+ struct event_mod_load *event_mod, *n;
+
+ list_for_each_entry_safe(event_mod, n, &tr->mod_events, list) {
+ if (strcmp(event_mod->module, mod->name) != 0)
+ continue;
+
+ __ftrace_set_clr_event_nolock(tr, event_mod->match,
+ event_mod->system,
+ event_mod->event, 1, mod->name);
+ free_event_mod(event_mod);
+ }
+}
+
+static void update_cache_events(struct module *mod)
+{
+ struct trace_array *tr;
+
+ list_for_each_entry(tr, &ftrace_trace_arrays, list)
+ update_mod_cache(tr, mod);
+}
static void trace_module_add_events(struct module *mod)
{
@@ -3221,6 +3679,8 @@ static void trace_module_add_events(struct module *mod)
__register_event(*call, mod);
__add_event_to_tracers(*call);
}
+
+ update_cache_events(mod);
}
static void trace_module_remove_events(struct module *mod)
@@ -3373,30 +3833,21 @@ struct trace_event_file *trace_get_event_file(const char *instance,
return ERR_PTR(ret);
}
- mutex_lock(&event_mutex);
+ guard(mutex)(&event_mutex);
file = find_event_file(tr, system, event);
if (!file) {
trace_array_put(tr);
- ret = -EINVAL;
- goto out;
+ return ERR_PTR(-EINVAL);
}
/* Don't let event modules unload while in use */
ret = trace_event_try_get_ref(file->event_call);
if (!ret) {
trace_array_put(tr);
- ret = -EBUSY;
- goto out;
+ return ERR_PTR(-EBUSY);
}
- ret = 0;
- out:
- mutex_unlock(&event_mutex);
-
- if (ret)
- file = ERR_PTR(ret);
-
return file;
}
EXPORT_SYMBOL_GPL(trace_get_event_file);
@@ -3614,6 +4065,7 @@ event_enable_func(struct trace_array *tr, struct ftrace_hash *hash,
struct trace_event_file *file;
struct ftrace_probe_ops *ops;
struct event_probe_data *data;
+ unsigned long count = -1;
const char *system;
const char *event;
char *number;
@@ -3633,12 +4085,11 @@ event_enable_func(struct trace_array *tr, struct ftrace_hash *hash,
event = strsep(&param, ":");
- mutex_lock(&event_mutex);
+ guard(mutex)(&event_mutex);
- ret = -EINVAL;
file = find_event_file(tr, system, event);
if (!file)
- goto out;
+ return -EINVAL;
enable = strcmp(cmd, ENABLE_EVENT_STR) == 0;
@@ -3647,74 +4098,62 @@ event_enable_func(struct trace_array *tr, struct ftrace_hash *hash,
else
ops = param ? &event_disable_count_probe_ops : &event_disable_probe_ops;
- if (glob[0] == '!') {
- ret = unregister_ftrace_function_probe_func(glob+1, tr, ops);
- goto out;
- }
+ if (glob[0] == '!')
+ return unregister_ftrace_function_probe_func(glob+1, tr, ops);
- ret = -ENOMEM;
+ if (param) {
+ number = strsep(&param, ":");
- data = kzalloc(sizeof(*data), GFP_KERNEL);
- if (!data)
- goto out;
+ if (!strlen(number))
+ return -EINVAL;
- data->enable = enable;
- data->count = -1;
- data->file = file;
-
- if (!param)
- goto out_reg;
-
- number = strsep(&param, ":");
-
- ret = -EINVAL;
- if (!strlen(number))
- goto out_free;
-
- /*
- * We use the callback data field (which is a pointer)
- * as our counter.
- */
- ret = kstrtoul(number, 0, &data->count);
- if (ret)
- goto out_free;
+ /*
+ * We use the callback data field (which is a pointer)
+ * as our counter.
+ */
+ ret = kstrtoul(number, 0, &count);
+ if (ret)
+ return ret;
+ }
- out_reg:
/* Don't let event modules unload while probe registered */
ret = trace_event_try_get_ref(file->event_call);
- if (!ret) {
- ret = -EBUSY;
- goto out_free;
- }
+ if (!ret)
+ return -EBUSY;
ret = __ftrace_event_enable_disable(file, 1, 1);
if (ret < 0)
goto out_put;
+ ret = -ENOMEM;
+ data = kzalloc(sizeof(*data), GFP_KERNEL);
+ if (!data)
+ goto out_put;
+
+ data->enable = enable;
+ data->count = count;
+ data->file = file;
+
ret = register_ftrace_function_probe(glob, tr, ops, data);
/*
* The above returns on success the # of functions enabled,
* but if it didn't find any functions it returns zero.
* Consider no functions a failure too.
*/
- if (!ret) {
- ret = -ENOENT;
- goto out_disable;
- } else if (ret < 0)
- goto out_disable;
+
/* Just return zero, not the number of enabled functions */
- ret = 0;
- out:
- mutex_unlock(&event_mutex);
- return ret;
+ if (ret > 0)
+ return 0;
+
+ kfree(data);
+
+ if (!ret)
+ ret = -ENOENT;
- out_disable:
__ftrace_event_enable_disable(file, 0, 1);
out_put:
trace_event_put_ref(file->event_call);
- out_free:
- kfree(data);
- goto out;
+ return ret;
}
static struct ftrace_func_command event_enable_cmd = {
@@ -3937,20 +4376,17 @@ early_event_add_tracer(struct dentry *parent, struct trace_array *tr)
{
int ret;
- mutex_lock(&event_mutex);
+ guard(mutex)(&event_mutex);
ret = create_event_toplevel_files(parent, tr);
if (ret)
- goto out_unlock;
+ return ret;
down_write(&trace_event_sem);
__trace_early_add_event_dirs(tr);
up_write(&trace_event_sem);
- out_unlock:
- mutex_unlock(&event_mutex);
-
- return ret;
+ return 0;
}
/* Must be called with event_mutex held */
@@ -3965,7 +4401,7 @@ int event_trace_del_tracer(struct trace_array *tr)
__ftrace_clear_event_pids(tr, TRACE_PIDS | TRACE_NO_PIDS);
/* Disable any running events */
- __ftrace_set_clr_event_nolock(tr, NULL, NULL, NULL, 0);
+ __ftrace_set_clr_event_nolock(tr, NULL, NULL, NULL, 0, NULL);
/* Make sure no more events are being executed */
tracepoint_synchronize_unregister();
@@ -4249,7 +4685,7 @@ static __init void event_trace_self_tests(void)
pr_info("Testing event system %s: ", system->name);
- ret = __ftrace_set_clr_event(tr, NULL, system->name, NULL, 1);
+ ret = __ftrace_set_clr_event(tr, NULL, system->name, NULL, 1, NULL);
if (WARN_ON_ONCE(ret)) {
pr_warn("error enabling system %s\n",
system->name);
@@ -4258,7 +4694,7 @@ static __init void event_trace_self_tests(void)
event_test_stuff();
- ret = __ftrace_set_clr_event(tr, NULL, system->name, NULL, 0);
+ ret = __ftrace_set_clr_event(tr, NULL, system->name, NULL, 0, NULL);
if (WARN_ON_ONCE(ret)) {
pr_warn("error disabling system %s\n",
system->name);
@@ -4273,7 +4709,7 @@ static __init void event_trace_self_tests(void)
pr_info("Running tests on all trace events:\n");
pr_info("Testing all events: ");
- ret = __ftrace_set_clr_event(tr, NULL, NULL, NULL, 1);
+ ret = __ftrace_set_clr_event(tr, NULL, NULL, NULL, 1, NULL);
if (WARN_ON_ONCE(ret)) {
pr_warn("error enabling all events\n");
return;
@@ -4282,7 +4718,7 @@ static __init void event_trace_self_tests(void)
event_test_stuff();
/* reset sysname */
- ret = __ftrace_set_clr_event(tr, NULL, NULL, NULL, 0);
+ ret = __ftrace_set_clr_event(tr, NULL, NULL, NULL, 0, NULL);
if (WARN_ON_ONCE(ret)) {
pr_warn("error disabling all events\n");
return;