From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail138.messagelabs.com (mail138.messagelabs.com [216.82.249.35]) by kanga.kvack.org (Postfix) with SMTP id 5A1896B009C for ; Mon, 8 Nov 2010 18:19:45 -0500 (EST) Message-Id: <20101108231726.848034006@intel.com> Date: Tue, 09 Nov 2010 07:09:18 +0800 From: Wu Fengguang Subject: [PATCH 2/5] writeback: trace wakeup event for background writeback References: <20101108230916.826791396@intel.com> Content-Disposition: inline; filename=mutt-wfg-t61-1000-20494-6680a464460b57571 Sender: owner-linux-mm@kvack.org To: Andrew Morton Cc: Jan Kara , linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, Johannes Weiner , Wu Fengguang , Christoph Hellwig , Jan Engelhardt , LKML List-ID: This tracks when balance_dirty_pages() tries to wakeup the flusher thread for background writeback (if it was not started already). Suggested-by: Christoph Hellwig Signed-off-by: Wu Fengguang --- fs/fs-writeback.c | 1 + include/trace/events/writeback.h | 1 + 2 files changed, 2 insertions(+) --- linux-next.orig/include/trace/events/writeback.h 2010-11-07 21:54:19.000000000 +0800 +++ linux-next/include/trace/events/writeback.h 2010-11-07 21:56:42.000000000 +0800 @@ -81,6 +81,7 @@ DEFINE_EVENT(writeback_class, name, \ TP_ARGS(bdi)) DEFINE_WRITEBACK_EVENT(writeback_nowork); +DEFINE_WRITEBACK_EVENT(writeback_wake_background); DEFINE_WRITEBACK_EVENT(writeback_wake_thread); DEFINE_WRITEBACK_EVENT(writeback_wake_forker_thread); DEFINE_WRITEBACK_EVENT(writeback_bdi_register); --- linux-next.orig/fs/fs-writeback.c 2010-11-07 21:54:19.000000000 +0800 +++ linux-next/fs/fs-writeback.c 2010-11-07 21:56:42.000000000 +0800 @@ -169,6 +169,7 @@ void bdi_start_background_writeback(stru * We just wake up the flusher thread. It will perform background * writeback as soon as there is no other work to do. */ + trace_writeback_wake_background(bdi); spin_lock_bh(&bdi->wb_lock); bdi_wakeup_flusher(bdi); spin_unlock_bh(&bdi->wb_lock); -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom policy in Canada: sign http://dissolvethecrtc.ca/ Don't email: email@kvack.org