Merge branch 'tip/perf/core-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace into perf/core

Pull ftrace fixlets from Steve Rostedt.

Signed-off-by: Ingo Molnar <mingo@kernel.org>

4 files changed, 19 insertions, 20 deletions

diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 49491fa7daa2..b32ed0e385a5 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -2816,7 +2816,7 @@ EXPORT_SYMBOL_GPL(ring_buffer_record_enable);
  * to the buffer after this will fail and return NULL.
  *
  * This is different than ring_buffer_record_disable() as
- * it works like an on/off switch, where as the disable() verison
+ * it works like an on/off switch, where as the disable() version
  * must be paired with a enable().
  */
 void ring_buffer_record_off(struct ring_buffer *buffer)
@@ -2839,7 +2839,7 @@ EXPORT_SYMBOL_GPL(ring_buffer_record_off);
  * ring_buffer_record_off().
  *
  * This is different than ring_buffer_record_enable() as
- * it works like an on/off switch, where as the enable() verison
+ * it works like an on/off switch, where as the enable() version
  * must be paired with a disable().
  */
 void ring_buffer_record_on(struct ring_buffer *buffer)
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 5c38c81496ce..08acf42e325b 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -426,15 +426,15 @@ __setup("trace_buf_size=", set_buf_size);
 
 static int __init set_tracing_thresh(char *str)
 {
-        unsigned long threshhold;
+        unsigned long threshold;
         int ret;
 
         if (!str)
                 return 0;
-        ret = strict_strtoul(str, 0, &threshhold);
+        ret = strict_strtoul(str, 0, &threshold);
         if (ret < 0)
                 return 0;
-        tracing_thresh = threshhold * 1000;
+        tracing_thresh = threshold * 1000;
         return 1;
 }
 __setup("tracing_thresh=", set_tracing_thresh);
diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c
index 431dba8b7542..c154797a7ff7 100644
--- a/kernel/trace/trace_events_filter.c
+++ b/kernel/trace/trace_events_filter.c
@@ -2002,7 +2002,7 @@ static int ftrace_function_set_regexp(struct ftrace_ops *ops, int filter,
 static int __ftrace_function_set_filter(int filter, char *buf, int len,
                                         struct function_filter_data *data)
 {
-        int i, re_cnt, ret;
+        int i, re_cnt, ret = -EINVAL;
         int *reset;
         char **re;
 
diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c
index 1003a4d5eb25..2c00a691a540 100644
--- a/kernel/trace/trace_selftest.c
+++ b/kernel/trace/trace_selftest.c
@@ -1041,6 +1041,8 @@ static int trace_wakeup_test_thread(void *data)
         set_current_state(TASK_INTERRUPTIBLE);
         schedule();
 
+        complete(x);
+
         /* we are awake, now wait to disappear */
         while (!kthread_should_stop()) {
                 /*
@@ -1084,24 +1086,21 @@ trace_selftest_startup_wakeup(struct tracer *trace, struct trace_array *tr)
         /* reset the max latency */
         tracing_max_latency = 0;
 
-        /* sleep to let the RT thread sleep too */
-        msleep(100);
+        while (p->on_rq) {
+                /*
+                 * Sleep to make sure the RT thread is asleep too.
+                 * On virtual machines we can't rely on timings,
+                 * but we want to make sure this test still works.
+                 */
+                msleep(100);
+        }
 
-        /*
-         * Yes this is slightly racy. It is possible that for some
-         * strange reason that the RT thread we created, did not
-         * call schedule for 100ms after doing the completion,
-         * and we do a wakeup on a task that already is awake.
-         * But that is extremely unlikely, and the worst thing that
-         * happens in such a case, is that we disable tracing.
-         * Honestly, if this race does happen something is horrible
-         * wrong with the system.
-         */
+        init_completion(&isrt);
 
         wake_up_process(p);
 
-        /* give a little time to let the thread wake up */
-        msleep(100);
+        /* Wait for the task to wake up */
+        wait_for_completion(&isrt);
 
         /* stop the tracing. */
         tracing_stop();