From: Steven Rostedt <rostedt@goodmis.org>
To: linux-kernel@vger.kernel.org
Cc: Ingo Molnar <mingo@kernel.org>,
Andrew Morton <akpm@linux-foundation.org>,
Thomas Gleixner <tglx@linutronix.de>,
Frederic Weisbecker <fweisbec@gmail.com>,
Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>,
David Sharp <dhsharp@google.com>,
Vaibhav Nagarnaik <vnagarnaik@google.com>,
hcochran@lexmark.com,
Hiraku Toyooka <hiraku.toyooka.gu@hitachi.com>
Subject: [for-next][PATCH 01/17] ring-buffer: Init waitqueue for blocked readers
Date: Thu, 07 Mar 2013 21:59:59 -0500 [thread overview]
Message-ID: <20130308030651.990309877@goodmis.org> (raw)
In-Reply-To: 20130308025958.501479677@goodmis.org
[-- Attachment #1: 0001-ring-buffer-Init-waitqueue-for-blocked-readers.patch --]
[-- Type: text/plain, Size: 1362 bytes --]
From: "Steven Rostedt (Red Hat)" <srostedt@redhat.com>
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>
---
kernel/trace/ring_buffer.c | 2 ++
1 file changed, 2 insertions(+)
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 @@ 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)
--
1.7.10.4
next prev parent reply other threads:[~2013-03-08 3:06 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-03-08 2:59 [for-next][PATCH 00/17] tracing: multi-buffers with snapshots, per_cpu and some debugging tools Steven Rostedt
2013-03-08 2:59 ` Steven Rostedt [this message]
2013-03-08 3:00 ` [for-next][PATCH 02/17] tracing: Add comment for trace event flag IGNORE_ENABLE Steven Rostedt
2013-03-08 3:00 ` [for-next][PATCH 03/17] tracing: Only clear trace buffer on module unload if event was traced Steven Rostedt
2013-03-08 3:00 ` [for-next][PATCH 04/17] tracing: Clear all trace buffers when unloaded module event was used Steven Rostedt
2013-03-08 3:00 ` [for-next][PATCH 05/17] tracing: Enable snapshot when any latency tracer is enabled Steven Rostedt
2013-03-08 3:00 ` [for-next][PATCH 06/17] tracing: Consolidate max_tr into main trace_array structure Steven Rostedt
2013-03-08 3:00 ` [for-next][PATCH 07/17] tracing: Add snapshot in the per_cpu trace directories Steven Rostedt
2013-03-08 3:00 ` [for-next][PATCH 08/17] tracing: Add config option to allow snapshot to swap per cpu Steven Rostedt
2013-03-08 3:00 ` [for-next][PATCH 09/17] tracing: Add snapshot_raw to extract the raw data from snapshot Steven Rostedt
2013-03-08 3:00 ` [for-next][PATCH 10/17] tracing: Have trace_array keep track if snapshot buffer is allocated Steven Rostedt
2013-03-08 3:00 ` [for-next][PATCH 11/17] tracing: Consolidate buffer allocation code Steven Rostedt
2013-03-08 3:00 ` [for-next][PATCH 12/17] tracing: Add snapshot feature to instances Steven Rostedt
2013-03-08 3:00 ` [for-next][PATCH 13/17] tracing: Add per_cpu directory into tracing instances Steven Rostedt
2013-03-08 3:00 ` [for-next][PATCH 14/17] tracing: Prevent deleting instances when they are being read Steven Rostedt
2013-03-08 3:00 ` [for-next][PATCH 15/17] tracing: Add internal tracing_snapshot() functions Steven Rostedt
2013-03-08 3:00 ` [for-next][PATCH 16/17] ring-buffer: Do not use schedule_work_on() for current CPU Steven Rostedt
2013-03-08 3:00 ` [for-next][PATCH 17/17] tracing: Move the tracing selftest code into its own function Steven Rostedt
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