From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756422Ab1LNBOG (ORCPT ); Tue, 13 Dec 2011 20:14:06 -0500 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.125]:38835 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756259Ab1LNBOD (ORCPT ); Tue, 13 Dec 2011 20:14:03 -0500 X-Authority-Analysis: v=2.0 cv=HeWWv148 c=1 sm=0 a=ZycB6UtQUfgMyuk2+PxD7w==:17 a=Sq825YaR5YAA:10 a=5SG0PmZfjMsA:10 a=Q9fys5e9bTEA:10 a=meVymXHHAAAA:8 a=LjNjP9thxtKzdCPQ4CgA:9 a=PUjeQqilurYA:10 a=jeBq3FmKZ4MA:10 a=ZycB6UtQUfgMyuk2+PxD7w==:117 X-Cloudmark-Score: 0 X-Originating-IP: 74.67.80.29 Message-ID: <1323825240.23971.11.camel@gandalf.stny.rr.com> Subject: [RFC][PATCH] writeback: Unduplicate writeback reason From: Steven Rostedt To: Wu Fengguang Cc: linux-fsdevel@vger.kernel.org, Curt Wohlgemuth , Jan Kara , Christoph Hellwig , LKML Date: Tue, 13 Dec 2011 20:14:00 -0500 In-Reply-To: <20111214003150.GA14520@localhost> References: <20111214003150.GA14520@localhost> Content-Type: text/plain; charset="ISO-8859-15" X-Mailer: Evolution 3.0.3-3 Content-Transfer-Encoding: 7bit Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Names of the writeback reasons are used in both the main kernel as well as for parsing the tracepoint format file. Instead of duplicating the names in two locations making it likely that they may become out of sync, use some macro magic to make sure all the names stay in sync. Any update only needs to happen in one spot for it to take place in all locations. Note, this is an RFC patch, and it probably needs much better comments (well, it currently has no comments), and the C() macro probably should have a different name too. Signed-off-by: Steven Rostedt Index: linux-trace.git/fs/fs-writeback.c =================================================================== --- linux-trace.git.orig/fs/fs-writeback.c +++ linux-trace.git/fs/fs-writeback.c @@ -47,15 +47,10 @@ struct wb_writeback_work { struct completion *done; /* set if the caller waits */ }; +#undef C +#define C(a, b) [a] = b const char *wb_reason_name[] = { - [WB_REASON_BACKGROUND] = "background", - [WB_REASON_TRY_TO_FREE_PAGES] = "try_to_free_pages", - [WB_REASON_SYNC] = "sync", - [WB_REASON_PERIODIC] = "periodic", - [WB_REASON_LAPTOP_TIMER] = "laptop_timer", - [WB_REASON_FREE_MORE_MEM] = "free_more_memory", - [WB_REASON_FS_FREE_SPACE] = "fs_free_space", - [WB_REASON_FORKER_THREAD] = "forker_thread" + WB_ENUM_REASONS }; /* Index: linux-trace.git/include/linux/writeback.h =================================================================== --- linux-trace.git.orig/include/linux/writeback.h +++ linux-trace.git/include/linux/writeback.h @@ -38,21 +38,23 @@ enum writeback_sync_modes { WB_SYNC_ALL, /* Wait on every mapping */ }; +#define WB_ENUM_REASONS \ + C(WB_REASON_BACKGROUND, "background"), \ + C(WB_REASON_TRY_TO_FREE_PAGES, "try_to_free_pages"), \ + C(WB_REASON_SYNC, "sync"), \ + C(WB_REASON_PERIODIC, "periodic"), \ + C(WB_REASON_LAPTOP_TIMER, "laptop_timer"), \ + C(WB_REASON_FREE_MORE_MEM, "free_more_memory"), \ + C(WB_REASON_FS_FREE_SPACE, "fs_free_space"), \ + C(WB_REASON_FORKER_THREAD, "forker_thread") + /* * why some writeback work was initiated */ -enum wb_reason { - WB_REASON_BACKGROUND, - WB_REASON_TRY_TO_FREE_PAGES, - WB_REASON_SYNC, - WB_REASON_PERIODIC, - WB_REASON_LAPTOP_TIMER, - WB_REASON_FREE_MORE_MEM, - WB_REASON_FS_FREE_SPACE, - WB_REASON_FORKER_THREAD, +#undef C +#define C(a, b) a +enum wb_reason { WB_ENUM_REASONS, WB_REASONS_MAX }; - WB_REASON_MAX, -}; extern const char *wb_reason_name[]; /* Index: linux-trace.git/include/trace/events/writeback.h =================================================================== --- linux-trace.git.orig/include/trace/events/writeback.h +++ linux-trace.git/include/trace/events/writeback.h @@ -21,16 +21,11 @@ {I_REFERENCED, "I_REFERENCED"} \ ) +#undef C +#define C(a, b) {a, b} #define show_work_reason(reason) \ __print_symbolic(reason, \ - {WB_REASON_BACKGROUND, "background"}, \ - {WB_REASON_TRY_TO_FREE_PAGES, "try_to_free_pages"}, \ - {WB_REASON_SYNC, "sync"}, \ - {WB_REASON_PERIODIC, "periodic"}, \ - {WB_REASON_LAPTOP_TIMER, "laptop_timer"}, \ - {WB_REASON_FREE_MORE_MEM, "free_more_memory"}, \ - {WB_REASON_FS_FREE_SPACE, "fs_free_space"}, \ - {WB_REASON_FORKER_THREAD, "forker_thread"} \ + WB_ENUM_REASONS \ ) struct wb_writeback_work;