diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h
index 3121b95443d97844abccee9215465eefe76b8a28..f368d041e02d1f41ccb36bda3a4c5da59c65df3d 100644
--- a/include/linux/ftrace.h
+++ b/include/linux/ftrace.h
@@ -89,6 +89,7 @@ void ftrace_enable_daemon(void);
/* totally disable ftrace - can not re-enable after this */
void ftrace_kill(void);
+void ftrace_kill_atomic(void);
static inline void tracer_disable(void)
{
diff --git a/kernel/Makefile b/kernel/Makefile
index ca2433e84873fce4c3b31789baf3ae723f864d69..480976275d98d40bff28d04d675fb663f358b253 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -11,7 +11,7 @@ obj-y = sched.o fork.o exec_domain.o panic.o printk.o profile.o \
hrtimer.o rwsem.o nsproxy.o srcu.o semaphore.o \
notifier.o ksysfs.o pm_qos_params.o sched_clock.o
-CFLAGS_REMOVE_sched.o = -pg -mno-spe
+CFLAGS_REMOVE_sched.o = -mno-spe
ifdef CONFIG_FTRACE
# Do not trace debug files and internal ftrace files
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 0f271c45cd02c9ed2b4130f30f7c8a8d40117dfc..4231a3dc224ac1f14460f63f195f7024980545c1 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -1601,6 +1601,23 @@ core_initcall(ftrace_dynamic_init);
# define ftrace_force_shutdown() do { } while (0)
#endif /* CONFIG_DYNAMIC_FTRACE */
+/**
+ * ftrace_kill_atomic - kill ftrace from critical sections
+ *
+ * This function should be used by panic code. It stops ftrace
+ * but in a not so nice way. If you need to simply kill ftrace
+ * from a non-atomic section, use ftrace_kill.
+ */
+void ftrace_kill_atomic(void)
+{
+ ftrace_disabled = 1;
+ ftrace_enabled = 0;
+#ifdef CONFIG_DYNAMIC_FTRACE
+ ftraced_suspend = -1;
+#endif
+ clear_ftrace_function();
+}
+
/**
* ftrace_kill - totally shutdown ftrace
*
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index e46de641ea44e03ff7646f070fe7f594f0596559..868e121c8e385f36604271ddf93d97bb92f24dd0 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -96,6 +96,9 @@ static DEFINE_PER_CPU(struct trace_array_cpu, max_data);
/* tracer_enabled is used to toggle activation of a tracer */
static int tracer_enabled = 1;
+/* function tracing enabled */
+int ftrace_function_enabled;
+
/*
* trace_nr_entries is the number of entries that is allocated
* for a buffer. Note, the number of entries is always rounded
@@ -134,6 +137,7 @@ static notrace void no_trace_init(struct trace_array *tr)
{
int cpu;
+ ftrace_function_enabled = 0;
if(tr->ctrl)
for_each_online_cpu(cpu)
tracing_reset(tr->data[cpu]);
@@ -1027,7 +1031,7 @@ function_trace_call(unsigned long ip, unsigned long parent_ip)
long disabled;
int cpu;
- if (unlikely(!tracer_enabled))
+ if (unlikely(!ftrace_function_enabled))
return;
if (skip_trace(ip))
@@ -1052,11 +1056,15 @@ static struct ftrace_ops trace_ops __read_mostly =
void tracing_start_function_trace(void)
{
+ ftrace_function_enabled = 0;
register_ftrace_function(&trace_ops);
+ if (tracer_enabled)
+ ftrace_function_enabled = 1;
}
void tracing_stop_function_trace(void)
{
+ ftrace_function_enabled = 0;
unregister_ftrace_function(&trace_ops);
}
#endif
@@ -1383,7 +1391,7 @@ print_trace_header(struct seq_file *m, struct trace_iterator *iter)
"server",
#elif defined(CONFIG_PREEMPT_VOLUNTARY)
"desktop",
-#elif defined(CONFIG_PREEMPT_DESKTOP)
+#elif defined(CONFIG_PREEMPT)
"preempt",
#else
"unknown",
@@ -1892,8 +1900,10 @@ __tracing_open(struct inode *inode, struct file *file, int *ret)
m->private = iter;
/* stop the trace while dumping */
- if (iter->tr->ctrl)
+ if (iter->tr->ctrl) {
tracer_enabled = 0;
+ ftrace_function_enabled = 0;
+ }
if (iter->trace && iter->trace->open)
iter->trace->open(iter);
@@ -1926,8 +1936,14 @@ int tracing_release(struct inode *inode, struct file *file)
iter->trace->close(iter);
/* reenable tracing if it was previously enabled */
- if (iter->tr->ctrl)
+ if (iter->tr->ctrl) {
tracer_enabled = 1;
+ /*
+ * It is safe to enable function tracing even if it
+ * isn't used
+ */
+ ftrace_function_enabled = 1;
+ }
mutex_unlock(&trace_types_lock);
seq_release(inode, file);
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 8cb215b239d50f8fa5b46966e9141d9ca8cdfd33..f69f86788c2bd12a2df18e4dabe9e66046a2e71f 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -223,8 +223,6 @@ void trace_function(struct trace_array *tr,
unsigned long parent_ip,
unsigned long flags);
-void tracing_start_function_trace(void);
-void tracing_stop_function_trace(void);
void tracing_start_cmdline_record(void);
void tracing_stop_cmdline_record(void);
int register_tracer(struct tracer *type);
@@ -241,6 +239,14 @@ void update_max_tr_single(struct trace_array *tr,
extern cycle_t ftrace_now(int cpu);
+#ifdef CONFIG_FTRACE
+void tracing_start_function_trace(void);
+void tracing_stop_function_trace(void);
+#else
+# define tracing_start_function_trace() do { } while (0)
+# define tracing_stop_function_trace() do { } while (0)
+#endif
+
#ifdef CONFIG_CONTEXT_SWITCH_TRACER
typedef void
(*tracer_switch_func_t)(void *private,
diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c
index 7ee7dcd76b7db76b5eca8afade67b6ce60365542..312144897970b18c7d9fd596bbf033182f68822b 100644
--- a/kernel/trace/trace_functions.c
+++ b/kernel/trace/trace_functions.c
@@ -28,7 +28,10 @@ static void function_reset(struct trace_array *tr)
static void start_function_trace(struct trace_array *tr)
{
+ tr->cpu = get_cpu();
function_reset(tr);
+ put_cpu();
+
tracing_start_cmdline_record();
tracing_start_function_trace();
}
diff --git a/kernel/trace/trace_sched_switch.c b/kernel/trace/trace_sched_switch.c
index 93a66200915181591c034b113226883f5696a31a..cb817a209aa005d9b151b79e2ef52b48178dffd4 100644
--- a/kernel/trace/trace_sched_switch.c
+++ b/kernel/trace/trace_sched_switch.c
@@ -227,14 +227,14 @@ void tracing_stop_cmdline_record(void)
static void start_sched_trace(struct trace_array *tr)
{
sched_switch_reset(tr);
- tracer_enabled = 1;
tracing_start_cmdline_record();
+ tracer_enabled = 1;
}
static void stop_sched_trace(struct trace_array *tr)
{
- tracing_stop_cmdline_record();
tracer_enabled = 0;
+ tracing_stop_cmdline_record();
}
static void sched_switch_trace_init(struct trace_array *tr)
diff --git a/kernel/trace/trace_sched_wakeup.c b/kernel/trace/trace_sched_wakeup.c
index bf7e91caef57d0ae6496688e82530598eab09421..3c8d61df4474adc473b107f04df43028f8efbee6 100644
--- a/kernel/trace/trace_sched_wakeup.c
+++ b/kernel/trace/trace_sched_wakeup.c
@@ -352,9 +352,10 @@ static void start_wakeup_tracer(struct trace_array *tr)
*/
smp_wmb();
- tracer_enabled = 1;
register_ftrace_function(&trace_ops);
+ tracer_enabled = 1;
+
return;
fail_deprobe_wake_new:
marker_probe_unregister("kernel_sched_wakeup_new",