From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752658Ab0FHAjJ (ORCPT ); Mon, 7 Jun 2010 20:39:09 -0400 Received: from bld-mail15.adl6.internode.on.net ([150.101.137.100]:47904 "EHLO mail.internode.on.net" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751670Ab0FHAjE (ORCPT ); Mon, 7 Jun 2010 20:39:04 -0400 From: Dave Chinner To: torvalds@linux-foundation.org Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, xfs@oss.sgi.com, akpm@linux-foundation.org Subject: [PATCH 3/6] writeback: Add tracing to write_cache_pages Date: Tue, 8 Jun 2010 10:38:04 +1000 Message-Id: <1275957487-23633-4-git-send-email-david@fromorbit.com> X-Mailer: git-send-email 1.7.1 In-Reply-To: <1275957487-23633-1-git-send-email-david@fromorbit.com> References: <1275957487-23633-1-git-send-email-david@fromorbit.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Dave Chinner Add a trace event to the ->writepage loop in write_cache_pages to give visibility into how the ->writepage call is changing variables within the writeback control structure. Of most interest is how wbc->nr_to_write changes from call to call, especially with filesystems that write multiple pages in ->writepage. Signed-off-by: Dave Chinner Reviewed-by: Christoph Hellwig --- include/trace/events/writeback.h | 1 + mm/page-writeback.c | 1 + 2 files changed, 2 insertions(+), 0 deletions(-) diff --git a/include/trace/events/writeback.h b/include/trace/events/writeback.h index 7867c16..6797c46 100644 --- a/include/trace/events/writeback.h +++ b/include/trace/events/writeback.h @@ -244,6 +244,7 @@ DEFINE_WBC_EVENT(wbc_writeback_wait); DEFINE_WBC_EVENT(wbc_balance_dirty_start); DEFINE_WBC_EVENT(wbc_balance_dirty_written); DEFINE_WBC_EVENT(wbc_balance_dirty_wait); +DEFINE_WBC_EVENT(wbc_writepage); #endif /* _TRACE_WRITEBACK_H */ diff --git a/mm/page-writeback.c b/mm/page-writeback.c index 345a730..7ac39c5 100644 --- a/mm/page-writeback.c +++ b/mm/page-writeback.c @@ -921,6 +921,7 @@ continue_unlock: if (!clear_page_dirty_for_io(page)) goto continue_unlock; + trace_wbc_writepage(wbc); ret = (*writepage)(page, wbc, data); if (unlikely(ret)) { if (ret == AOP_WRITEPAGE_ACTIVATE) { -- 1.7.1