1 files changed, 30 insertions, 14 deletions

diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index b21bf14bae9b..c366a0a9ddba 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -2062,8 +2062,10 @@ rb_insert_pages(struct ring_buffer_per_cpu *cpu_buffer)
 {
 	struct list_head *pages = &cpu_buffer->new_pages;
 	int retries, success;
+	unsigned long flags;
 
-	raw_spin_lock_irq(&cpu_buffer->reader_lock);
+	/* Can be called at early boot up, where interrupts must not been enabled */
+	raw_spin_lock_irqsave(&cpu_buffer->reader_lock, flags);
 	/*
 	 * We are holding the reader lock, so the reader page won't be swapped
 	 * in the ring buffer. Now we are racing with the writer trying to
@@ -2120,7 +2122,7 @@ rb_insert_pages(struct ring_buffer_per_cpu *cpu_buffer)
 	 * tracing
 	 */
 	RB_WARN_ON(cpu_buffer, !success);
-	raw_spin_unlock_irq(&cpu_buffer->reader_lock);
+	raw_spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags);
 
 	/* free pages if they weren't inserted */
 	if (!success) {
@@ -2248,8 +2250,16 @@ int ring_buffer_resize(struct trace_buffer *buffer, unsigned long size,
 				rb_update_pages(cpu_buffer);
 				cpu_buffer->nr_pages_to_update = 0;
 			} else {
-				schedule_work_on(cpu,
-						&cpu_buffer->update_pages_work);
+				/* Run directly if possible. */
+				migrate_disable();
+				if (cpu != smp_processor_id()) {
+					migrate_enable();
+					schedule_work_on(cpu,
+							 &cpu_buffer->update_pages_work);
+				} else {
+					update_pages_handler(&cpu_buffer->update_pages_work);
+					migrate_enable();
+				}
 			}
 		}
 
@@ -2298,9 +2308,17 @@ int ring_buffer_resize(struct trace_buffer *buffer, unsigned long size,
 		if (!cpu_online(cpu_id))
 			rb_update_pages(cpu_buffer);
 		else {
-			schedule_work_on(cpu_id,
-					 &cpu_buffer->update_pages_work);
-			wait_for_completion(&cpu_buffer->update_done);
+			/* Run directly if possible. */
+			migrate_disable();
+			if (cpu_id == smp_processor_id()) {
+				rb_update_pages(cpu_buffer);
+				migrate_enable();
+			} else {
+				migrate_enable();
+				schedule_work_on(cpu_id,
+						 &cpu_buffer->update_pages_work);
+				wait_for_completion(&cpu_buffer->update_done);
+			}
 		}
 
 		cpu_buffer->nr_pages_to_update = 0;
@@ -3180,8 +3198,7 @@ static inline void rb_event_discard(struct ring_buffer_event *event)
 		event->time_delta = 1;
 }
 
-static void rb_commit(struct ring_buffer_per_cpu *cpu_buffer,
-		      struct ring_buffer_event *event)
+static void rb_commit(struct ring_buffer_per_cpu *cpu_buffer)
 {
 	local_inc(&cpu_buffer->entries);
 	rb_end_commit(cpu_buffer);
@@ -3383,15 +3400,14 @@ void ring_buffer_nest_end(struct trace_buffer *buffer)
  *
  * Must be paired with ring_buffer_lock_reserve.
  */
-int ring_buffer_unlock_commit(struct trace_buffer *buffer,
-			      struct ring_buffer_event *event)
+int ring_buffer_unlock_commit(struct trace_buffer *buffer)
 {
 	struct ring_buffer_per_cpu *cpu_buffer;
 	int cpu = raw_smp_processor_id();
 
 	cpu_buffer = buffer->buffers[cpu];
 
-	rb_commit(cpu_buffer, event);
+	rb_commit(cpu_buffer);
 
 	rb_wakeups(buffer, cpu_buffer);
 
@@ -3977,7 +3993,7 @@ int ring_buffer_write(struct trace_buffer *buffer,
 
 	memcpy(body, data, length);
 
-	rb_commit(cpu_buffer, event);
+	rb_commit(cpu_buffer);
 
 	rb_wakeups(buffer, cpu_buffer);
 
@@ -5998,7 +6014,7 @@ static __init int rb_write_something(struct rb_test_data *data, bool nested)
 	}
 
  out:
-	ring_buffer_unlock_commit(data->buffer, event);
+	ring_buffer_unlock_commit(data->buffer);
 
 	return 0;
 }