From: Steven Rostedt (Red Hat) Date: Mon, 4 Mar 2013 22:33:05 +0000 (-0500) Subject: ring-buffer: Init waitqueue for blocked readers X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=f1dc6725882b5ca54eb9a04436a3b47d58f2cbc7;p=GitHub%2FLineageOS%2Fandroid_kernel_samsung_universal7580.git 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 --- diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index 56b6ea32d2e..65fe2a4f982 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -1185,6 +1185,7 @@ rb_allocate_cpu_buffer(struct ring_buffer *buffer, int nr_pages, int cpu) 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 @@ struct ring_buffer *__ring_buffer_alloc(unsigned long size, unsigned flags, 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)