From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id AC809C43331 for ; Fri, 3 Apr 2020 08:36:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6F8482080C for ; Fri, 3 Apr 2020 08:36:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1585902966; bh=MOfPLrlsatJ/UDoiti/D/dKR9/7N5fw8hIa9Xd/DToY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=x1Kv3GpGUAsqY1ohbDP2cIU0+IkuHWv61uOSQiXV17O/gMVBb6MS5nqTag0HB8MKB owqvH/4ftPuruQlnhp5+pYJNt6h/5Pi97aXh+lita0l17hmG0bWbMvqnhpLLTb/80Y 2BmHT6o95E54cdgOu4Nak196XxsrqbJ160T0sXBQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390529AbgDCIgF (ORCPT ); Fri, 3 Apr 2020 04:36:05 -0400 Received: from mail-wr1-f67.google.com ([209.85.221.67]:37885 "EHLO mail-wr1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727774AbgDCIgC (ORCPT ); Fri, 3 Apr 2020 04:36:02 -0400 Received: by mail-wr1-f67.google.com with SMTP id w10so7513582wrm.4 for ; Fri, 03 Apr 2020 01:36:00 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=YmqsIpFQyQQ2Lq3jQLn2ED6h63YdDDqWuKLktL963FE=; b=SJ97OZH9O5N5ygZtYvx6VRn5CNZ+eeV+YYI7T0CiEY7zG0dvON0OrGcvocQ7veqYIa VzuoDgTpADbKCDXTukTMGr+UvsFzbzfIq/irZJAZzZHthm1AnQT8vYHGP+vvKaoq+Co1 O/GxLMd9P+xpRTC//DTv/x7GkV1AApGmZWkFnhYEUSKtIAoq6zAQBN1BkmsRCKpMzrpt PwdjNFrD6VFzQT3PzO0nDXHqWp0MIPKFuQaUpObifydDjtB1KUWD2yw8v7i+H5LtNl5M bAfuMk18cUpS1KhwE+vYTE1vHxhxHj2KzjY/OLHnF7uUuQoryk/gx5jLvbqdi7FzcTXE ZEyw== X-Gm-Message-State: AGi0PuZLI5pY86mJl6u4L2oyNSJbcsst/pOxMsvy+B47dCFQ0EVP4XYK VKacbUInEyFUOtFXmMaNwKTW9hP4 X-Google-Smtp-Source: APiQypIG8pcQaw6IRSWQM+d3AwV+GjfW87kcXS+FPtd04pS58lgtBWpzeJsDAmRETTcbde+50hc16A== X-Received: by 2002:a05:6000:11c6:: with SMTP id i6mr8126218wrx.115.1585902959941; Fri, 03 Apr 2020 01:35:59 -0700 (PDT) Received: from tiehlicka.suse.cz (ip-37-188-180-223.eurotel.cz. [37.188.180.223]) by smtp.gmail.com with ESMTPSA id v7sm11010275wrs.96.2020.04.03.01.35.58 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 03 Apr 2020 01:35:59 -0700 (PDT) From: Michal Hocko To: Andrew Morton Cc: Joel Fernandes , "Paul E. McKenney" , Neil Brown , , LKML , Michal Hocko , "Paul E . McKenney" Subject: [PATCH 2/2] mm: make it clear that gfp reclaim modifiers are valid only for sleepable allocations Date: Fri, 3 Apr 2020 10:35:43 +0200 Message-Id: <20200403083543.11552-3-mhocko@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200403083543.11552-1-mhocko@kernel.org> References: <20200403083543.11552-1-mhocko@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Michal Hocko While it might be really clear to MM developers that gfp reclaim modifiers are applicable only to sleepable allocations (those with __GFP_DIRECT_RECLAIM) it seems that actual users of the API are not always sure. Make it explicit that they are not applicable for GFP_NOWAIT or GFP_ATOMIC allocations which are the most commonly used non-sleepable allocation masks. Acked-by: Paul E. McKenney Signed-off-by: Michal Hocko --- include/linux/gfp.h | 2 ++ 1 file changed, 2 insertions(+) diff --git a/include/linux/gfp.h b/include/linux/gfp.h index e3ab1c0d9140..8040fa944cd8 100644 --- a/include/linux/gfp.h +++ b/include/linux/gfp.h @@ -127,6 +127,8 @@ struct vm_area_struct; * * Reclaim modifiers * ~~~~~~~~~~~~~~~~~ + * Please note that all the following flags are only applicable to sleepable + * allocations (e.g. %GFP_NOWAIT and %GFP_ATOMIC will ignore them). * * %__GFP_IO can start physical IO. * -- 2.25.1