ring-buffer: Init waitqueue for blocked readers
The move of blocked readers to the ring buffer left out the
init of the wait queue that is used. Tests missed this due to running
stress tests against the buffers, which didn't allow for any
readers to end up waiting. Running a simple read and wait triggered
a bug.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 56b6ea3..65fe2a4 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -1185,6 +1185,7 @@
INIT_WORK(&cpu_buffer->update_pages_work, update_pages_handler);
init_completion(&cpu_buffer->update_done);
init_irq_work(&cpu_buffer->irq_work.work, rb_wake_up_waiters);
+ init_waitqueue_head(&cpu_buffer->irq_work.waiters);
bpage = kzalloc_node(ALIGN(sizeof(*bpage), cache_line_size()),
GFP_KERNEL, cpu_to_node(cpu));
@@ -1281,6 +1282,7 @@
buffer->reader_lock_key = key;
init_irq_work(&buffer->irq_work.work, rb_wake_up_waiters);
+ init_waitqueue_head(&buffer->irq_work.waiters);
/* need at least two pages */
if (nr_pages < 2)