From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-it0-f69.google.com (mail-it0-f69.google.com [209.85.214.69]) by kanga.kvack.org (Postfix) with ESMTP id ADBE06B0069 for ; Fri, 24 Nov 2017 06:36:52 -0500 (EST) Received: by mail-it0-f69.google.com with SMTP id y71so5700829ita.4 for ; Fri, 24 Nov 2017 03:36:52 -0800 (PST) Received: from www262.sakura.ne.jp (www262.sakura.ne.jp. [2001:e42:101:1:202:181:97:72]) by mx.google.com with ESMTPS id 65si9402685iti.86.2017.11.24.03.36.51 for (version=TLS1 cipher=AES128-SHA bits=128/128); Fri, 24 Nov 2017 03:36:51 -0800 (PST) From: Tetsuo Handa Subject: [PATCH v2 2/2] mm,vmscan: Mark register_shrinker() as __must_check Date: Fri, 24 Nov 2017 20:36:25 +0900 Message-Id: <1511523385-6433-2-git-send-email-penguin-kernel@I-love.SAKURA.ne.jp> In-Reply-To: <1511523385-6433-1-git-send-email-penguin-kernel@I-love.SAKURA.ne.jp> References: <1511523385-6433-1-git-send-email-penguin-kernel@I-love.SAKURA.ne.jp> Sender: owner-linux-mm@kvack.org List-ID: To: linux-mm@kvack.org Cc: akpm@linux-foundation.org, mhocko@kernel.org, Tetsuo Handa , Al Viro , Glauber Costa Commit 1d3d4437eae1bb29 ("vmscan: per-node deferred work") changed register_shrinker() to fail when memory allocation failed. Since that commit did not take appropriate precautions before allowing register_shrinker() to fail, there are many register_shrinker() users who continue running when register_shrinker() failed. Since continuing when register_shrinker() failed can cause memory pressure related issues (e.g. needless OOM killer invocations), this patch marks register_shrinker() as __must_check in order to encourage all register_shrinker() users to add error recovery path. Signed-off-by: Tetsuo Handa Cc: Glauber Costa Cc: Al Viro --- include/linux/shrinker.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/include/linux/shrinker.h b/include/linux/shrinker.h index 388ff29..a389491 100644 --- a/include/linux/shrinker.h +++ b/include/linux/shrinker.h @@ -75,6 +75,6 @@ struct shrinker { #define SHRINKER_NUMA_AWARE (1 << 0) #define SHRINKER_MEMCG_AWARE (1 << 1) -extern int register_shrinker(struct shrinker *); +extern __must_check int register_shrinker(struct shrinker *); extern void unregister_shrinker(struct shrinker *); #endif -- 1.8.3.1 -- 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/ . Don't email: email@kvack.org