From mboxrd@z Thu Jan 1 00:00:00 1970 From: Artem Bityutskiy Subject: [PATCHv3 14/14] writeback: add new tracepoints Date: Thu, 22 Jul 2010 16:56:28 +0300 Message-ID: <1279806988-14100-15-git-send-email-dedekind1@gmail.com> References: <1279806988-14100-1-git-send-email-dedekind1@gmail.com> Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org To: Jens Axboe Return-path: Received: from smtp.nokia.com ([192.100.105.134]:52147 "EHLO mgw-mx09.nokia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932321Ab0GVN5J (ORCPT ); Thu, 22 Jul 2010 09:57:09 -0400 In-Reply-To: <1279806988-14100-1-git-send-email-dedekind1@gmail.com> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: From: Artem Bityutskiy Add 2 new trace points to the periodic write-back wake up case, just like we do in the 'bdi_queue_work()' function. Namely, introduce: 1. trace_writeback_wakeup(bdi) 2. trace_writeback_wakeup_nothread(bdi) The first event is triggered every time we wake up a bdi thread to start periodic background write-out. The second event is triggered only when the bdi thread does not exist and should be created by the forker thread. This patch was suggested by Dave Chinner Signed-off-by: Artem Bityutskiy --- include/trace/events/writeback.h | 2 ++ mm/backing-dev.c | 3 +++ 2 files changed, 5 insertions(+), 0 deletions(-) diff --git a/include/trace/events/writeback.h b/include/trace/events/writeback.h index 84ab72d..eb07d48 100644 --- a/include/trace/events/writeback.h +++ b/include/trace/events/writeback.h @@ -81,6 +81,8 @@ DEFINE_EVENT(writeback_class, name, \ TP_ARGS(bdi)) DEFINE_WRITEBACK_EVENT(writeback_nowork); +DEFINE_WRITEBACK_EVENT(writeback_wakeup); +DEFINE_WRITEBACK_EVENT(writeback_wakeup_nothread); DEFINE_WRITEBACK_EVENT(writeback_bdi_register); DEFINE_WRITEBACK_EVENT(writeback_bdi_unregister); DEFINE_WRITEBACK_EVENT(writeback_thread_start); diff --git a/mm/backing-dev.c b/mm/backing-dev.c index 90e56ab..9143f93 100644 --- a/mm/backing-dev.c +++ b/mm/backing-dev.c @@ -308,6 +308,8 @@ static void wakeup_timer_fn(unsigned long data) { struct backing_dev_info *bdi = (struct backing_dev_info *)data; + trace_writeback_wakeup(bdi); + spin_lock(&bdi->wb_lock); if (bdi->wb.task) { wake_up_process(bdi->wb.task); @@ -317,6 +319,7 @@ static void wakeup_timer_fn(unsigned long data) * In this case we have to wake-up the forker thread which * should create and run the bdi thread. */ + trace_writeback_wakeup_nothread(bdi); wake_up_process(default_backing_dev_info.wb.task); } spin_unlock(&bdi->wb_lock); -- 1.7.1.1