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-rw-r--r--kernel/trace/trace.c320
1 files changed, 171 insertions, 149 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index f40d850ebabc..4c187740c0df 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -251,6 +251,145 @@ unsigned long long ns2usecs(u64 nsec)
return nsec;
}
+static void
+trace_process_export(struct trace_export *export,
+ struct ring_buffer_event *event, int flag)
+{
+ struct trace_entry *entry;
+ unsigned int size = 0;
+
+ if (export->flags & flag) {
+ entry = ring_buffer_event_data(event);
+ size = ring_buffer_event_length(event);
+ export->write(export, entry, size);
+ }
+}
+
+static DEFINE_MUTEX(ftrace_export_lock);
+
+static struct trace_export __rcu *ftrace_exports_list __read_mostly;
+
+static DEFINE_STATIC_KEY_FALSE(trace_function_exports_enabled);
+static DEFINE_STATIC_KEY_FALSE(trace_event_exports_enabled);
+static DEFINE_STATIC_KEY_FALSE(trace_marker_exports_enabled);
+
+static inline void ftrace_exports_enable(struct trace_export *export)
+{
+ if (export->flags & TRACE_EXPORT_FUNCTION)
+ static_branch_inc(&trace_function_exports_enabled);
+
+ if (export->flags & TRACE_EXPORT_EVENT)
+ static_branch_inc(&trace_event_exports_enabled);
+
+ if (export->flags & TRACE_EXPORT_MARKER)
+ static_branch_inc(&trace_marker_exports_enabled);
+}
+
+static inline void ftrace_exports_disable(struct trace_export *export)
+{
+ if (export->flags & TRACE_EXPORT_FUNCTION)
+ static_branch_dec(&trace_function_exports_enabled);
+
+ if (export->flags & TRACE_EXPORT_EVENT)
+ static_branch_dec(&trace_event_exports_enabled);
+
+ if (export->flags & TRACE_EXPORT_MARKER)
+ static_branch_dec(&trace_marker_exports_enabled);
+}
+
+static void ftrace_exports(struct ring_buffer_event *event, int flag)
+{
+ struct trace_export *export;
+
+ preempt_disable_notrace();
+
+ export = rcu_dereference_raw_check(ftrace_exports_list);
+ while (export) {
+ trace_process_export(export, event, flag);
+ export = rcu_dereference_raw_check(export->next);
+ }
+
+ preempt_enable_notrace();
+}
+
+static inline void
+add_trace_export(struct trace_export **list, struct trace_export *export)
+{
+ rcu_assign_pointer(export->next, *list);
+ /*
+ * We are entering export into the list but another
+ * CPU might be walking that list. We need to make sure
+ * the export->next pointer is valid before another CPU sees
+ * the export pointer included into the list.
+ */
+ rcu_assign_pointer(*list, export);
+}
+
+static inline int
+rm_trace_export(struct trace_export **list, struct trace_export *export)
+{
+ struct trace_export **p;
+
+ for (p = list; *p != NULL; p = &(*p)->next)
+ if (*p == export)
+ break;
+
+ if (*p != export)
+ return -1;
+
+ rcu_assign_pointer(*p, (*p)->next);
+
+ return 0;
+}
+
+static inline void
+add_ftrace_export(struct trace_export **list, struct trace_export *export)
+{
+ ftrace_exports_enable(export);
+
+ add_trace_export(list, export);
+}
+
+static inline int
+rm_ftrace_export(struct trace_export **list, struct trace_export *export)
+{
+ int ret;
+
+ ret = rm_trace_export(list, export);
+ ftrace_exports_disable(export);
+
+ return ret;
+}
+
+int register_ftrace_export(struct trace_export *export)
+{
+ if (WARN_ON_ONCE(!export->write))
+ return -1;
+
+ mutex_lock(&ftrace_export_lock);
+
+ add_ftrace_export(&ftrace_exports_list, export);
+
+ mutex_unlock(&ftrace_export_lock);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(register_ftrace_export);
+
+int unregister_ftrace_export(struct trace_export *export)
+{
+ int ret;
+
+ mutex_lock(&ftrace_export_lock);
+
+ ret = rm_ftrace_export(&ftrace_exports_list, export);
+
+ mutex_unlock(&ftrace_export_lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(unregister_ftrace_export);
+
/* trace_flags holds trace_options default values */
#define TRACE_DEFAULT_FLAGS \
(FUNCTION_DEFAULT_FLAGS | \
@@ -2699,6 +2838,8 @@ void trace_event_buffer_commit(struct trace_event_buffer *fbuffer)
if (static_key_false(&tracepoint_printk_key.key))
output_printk(fbuffer);
+ if (static_branch_unlikely(&trace_event_exports_enabled))
+ ftrace_exports(fbuffer->event, TRACE_EXPORT_EVENT);
event_trigger_unlock_commit_regs(fbuffer->trace_file, fbuffer->buffer,
fbuffer->event, fbuffer->entry,
fbuffer->flags, fbuffer->pc, fbuffer->regs);
@@ -2742,129 +2883,6 @@ trace_buffer_unlock_commit_nostack(struct trace_buffer *buffer,
__buffer_unlock_commit(buffer, event);
}
-static void
-trace_process_export(struct trace_export *export,
- struct ring_buffer_event *event)
-{
- struct trace_entry *entry;
- unsigned int size = 0;
-
- entry = ring_buffer_event_data(event);
- size = ring_buffer_event_length(event);
- export->write(export, entry, size);
-}
-
-static DEFINE_MUTEX(ftrace_export_lock);
-
-static struct trace_export __rcu *ftrace_exports_list __read_mostly;
-
-static DEFINE_STATIC_KEY_FALSE(ftrace_exports_enabled);
-
-static inline void ftrace_exports_enable(void)
-{
- static_branch_enable(&ftrace_exports_enabled);
-}
-
-static inline void ftrace_exports_disable(void)
-{
- static_branch_disable(&ftrace_exports_enabled);
-}
-
-static void ftrace_exports(struct ring_buffer_event *event)
-{
- struct trace_export *export;
-
- preempt_disable_notrace();
-
- export = rcu_dereference_raw_check(ftrace_exports_list);
- while (export) {
- trace_process_export(export, event);
- export = rcu_dereference_raw_check(export->next);
- }
-
- preempt_enable_notrace();
-}
-
-static inline void
-add_trace_export(struct trace_export **list, struct trace_export *export)
-{
- rcu_assign_pointer(export->next, *list);
- /*
- * We are entering export into the list but another
- * CPU might be walking that list. We need to make sure
- * the export->next pointer is valid before another CPU sees
- * the export pointer included into the list.
- */
- rcu_assign_pointer(*list, export);
-}
-
-static inline int
-rm_trace_export(struct trace_export **list, struct trace_export *export)
-{
- struct trace_export **p;
-
- for (p = list; *p != NULL; p = &(*p)->next)
- if (*p == export)
- break;
-
- if (*p != export)
- return -1;
-
- rcu_assign_pointer(*p, (*p)->next);
-
- return 0;
-}
-
-static inline void
-add_ftrace_export(struct trace_export **list, struct trace_export *export)
-{
- if (*list == NULL)
- ftrace_exports_enable();
-
- add_trace_export(list, export);
-}
-
-static inline int
-rm_ftrace_export(struct trace_export **list, struct trace_export *export)
-{
- int ret;
-
- ret = rm_trace_export(list, export);
- if (*list == NULL)
- ftrace_exports_disable();
-
- return ret;
-}
-
-int register_ftrace_export(struct trace_export *export)
-{
- if (WARN_ON_ONCE(!export->write))
- return -1;
-
- mutex_lock(&ftrace_export_lock);
-
- add_ftrace_export(&ftrace_exports_list, export);
-
- mutex_unlock(&ftrace_export_lock);
-
- return 0;
-}
-EXPORT_SYMBOL_GPL(register_ftrace_export);
-
-int unregister_ftrace_export(struct trace_export *export)
-{
- int ret;
-
- mutex_lock(&ftrace_export_lock);
-
- ret = rm_ftrace_export(&ftrace_exports_list, export);
-
- mutex_unlock(&ftrace_export_lock);
-
- return ret;
-}
-EXPORT_SYMBOL_GPL(unregister_ftrace_export);
-
void
trace_function(struct trace_array *tr,
unsigned long ip, unsigned long parent_ip, unsigned long flags,
@@ -2884,8 +2902,8 @@ trace_function(struct trace_array *tr,
entry->parent_ip = parent_ip;
if (!call_filter_check_discard(call, entry, buffer, event)) {
- if (static_branch_unlikely(&ftrace_exports_enabled))
- ftrace_exports(event);
+ if (static_branch_unlikely(&trace_function_exports_enabled))
+ ftrace_exports(event, TRACE_EXPORT_FUNCTION);
__buffer_unlock_commit(buffer, event);
}
}
@@ -3546,13 +3564,15 @@ struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
if (iter->ent && iter->ent != iter->temp) {
if ((!iter->temp || iter->temp_size < iter->ent_size) &&
!WARN_ON_ONCE(iter->temp == static_temp_buf)) {
- kfree(iter->temp);
- iter->temp = kmalloc(iter->ent_size, GFP_KERNEL);
- if (!iter->temp)
+ void *temp;
+ temp = kmalloc(iter->ent_size, GFP_KERNEL);
+ if (!temp)
return NULL;
+ kfree(iter->temp);
+ iter->temp = temp;
+ iter->temp_size = iter->ent_size;
}
memcpy(iter->temp, iter->ent, iter->ent_size);
- iter->temp_size = iter->ent_size;
iter->ent = iter->temp;
}
entry = __find_next_entry(iter, ent_cpu, NULL, ent_ts);
@@ -3782,14 +3802,14 @@ unsigned long trace_total_entries(struct trace_array *tr)
static void print_lat_help_header(struct seq_file *m)
{
- seq_puts(m, "# _------=> CPU# \n"
- "# / _-----=> irqs-off \n"
- "# | / _----=> need-resched \n"
- "# || / _---=> hardirq/softirq \n"
- "# ||| / _--=> preempt-depth \n"
- "# |||| / delay \n"
- "# cmd pid ||||| time | caller \n"
- "# \\ / ||||| \\ | / \n");
+ seq_puts(m, "# _------=> CPU# \n"
+ "# / _-----=> irqs-off \n"
+ "# | / _----=> need-resched \n"
+ "# || / _---=> hardirq/softirq \n"
+ "# ||| / _--=> preempt-depth \n"
+ "# |||| / delay \n"
+ "# cmd pid ||||| time | caller \n"
+ "# \\ / ||||| \\ | / \n");
}
static void print_event_info(struct array_buffer *buf, struct seq_file *m)
@@ -3810,26 +3830,26 @@ static void print_func_help_header(struct array_buffer *buf, struct seq_file *m,
print_event_info(buf, m);
- seq_printf(m, "# TASK-PID %s CPU# TIMESTAMP FUNCTION\n", tgid ? "TGID " : "");
- seq_printf(m, "# | | %s | | |\n", tgid ? " | " : "");
+ seq_printf(m, "# TASK-PID %s CPU# TIMESTAMP FUNCTION\n", tgid ? " TGID " : "");
+ seq_printf(m, "# | | %s | | |\n", tgid ? " | " : "");
}
static void print_func_help_header_irq(struct array_buffer *buf, struct seq_file *m,
unsigned int flags)
{
bool tgid = flags & TRACE_ITER_RECORD_TGID;
- const char *space = " ";
- int prec = tgid ? 10 : 2;
+ const char *space = " ";
+ int prec = tgid ? 12 : 2;
print_event_info(buf, m);
- seq_printf(m, "# %.*s _-----=> irqs-off\n", prec, space);
- seq_printf(m, "# %.*s / _----=> need-resched\n", prec, space);
- seq_printf(m, "# %.*s| / _---=> hardirq/softirq\n", prec, space);
- seq_printf(m, "# %.*s|| / _--=> preempt-depth\n", prec, space);
- seq_printf(m, "# %.*s||| / delay\n", prec, space);
- seq_printf(m, "# TASK-PID %.*sCPU# |||| TIMESTAMP FUNCTION\n", prec, " TGID ");
- seq_printf(m, "# | | %.*s | |||| | |\n", prec, " | ");
+ seq_printf(m, "# %.*s _-----=> irqs-off\n", prec, space);
+ seq_printf(m, "# %.*s / _----=> need-resched\n", prec, space);
+ seq_printf(m, "# %.*s| / _---=> hardirq/softirq\n", prec, space);
+ seq_printf(m, "# %.*s|| / _--=> preempt-depth\n", prec, space);
+ seq_printf(m, "# %.*s||| / delay\n", prec, space);
+ seq_printf(m, "# TASK-PID %.*s CPU# |||| TIMESTAMP FUNCTION\n", prec, " TGID ");
+ seq_printf(m, "# | | %.*s | |||| | |\n", prec, " | ");
}
void
@@ -6676,6 +6696,8 @@ tracing_mark_write(struct file *filp, const char __user *ubuf,
} else
entry->buf[cnt] = '\0';
+ if (static_branch_unlikely(&trace_marker_exports_enabled))
+ ftrace_exports(event, TRACE_EXPORT_MARKER);
__buffer_unlock_commit(buffer, event);
if (tt)
@@ -9072,7 +9094,7 @@ static int trace_module_notify(struct notifier_block *self,
break;
}
- return 0;
+ return NOTIFY_OK;
}
static struct notifier_block trace_module_nb = {
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.