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=-3.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 12DACC2BA80 for ; Tue, 7 Apr 2020 03:04:09 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id C9B4A20936 for ; Tue, 7 Apr 2020 03:04:08 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="X+640FUM" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C9B4A20936 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 80DE68E0016; Mon, 6 Apr 2020 23:04:08 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 7C1898E0001; Mon, 6 Apr 2020 23:04:08 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 687F38E0016; Mon, 6 Apr 2020 23:04:08 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0246.hostedemail.com [216.40.44.246]) by kanga.kvack.org (Postfix) with ESMTP id 448648E0001 for ; Mon, 6 Apr 2020 23:04:08 -0400 (EDT) Received: from smtpin06.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 11EB199AC for ; Tue, 7 Apr 2020 03:04:08 +0000 (UTC) X-FDA: 76679564976.06.glass20_5e434c3a95300 X-HE-Tag: glass20_5e434c3a95300 X-Filterd-Recvd-Size: 2833 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf19.hostedemail.com (Postfix) with ESMTP for ; Tue, 7 Apr 2020 03:04:07 +0000 (UTC) Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id AAC9F208FE; Tue, 7 Apr 2020 03:04:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586228647; bh=hfivn8aZHAvSCEoM1yYa6VOnZeBFmjmfBhE86gypDwI=; h=Date:From:To:Subject:In-Reply-To:From; b=X+640FUMH+9LFDUch0BjqXhNplC0G8TLKWmcOkD8OBbRNtb7KyzdhOynKpjbuCiHi Ala61Kf+OTiHeUy3KMXWsK7s1HTgrXL4bBqWBr9dqiDXNwrOPq+J7o6HbxEdfM0Z2I bpaV2VKj3e1iJryOCHWsez0AhuwHnkZIDWLK1qK0= Date: Mon, 06 Apr 2020 20:04:06 -0700 From: Andrew Morton To: akpm@linux-foundation.org, joel@joelfernandes.org, linux-mm@kvack.org, mhocko@suse.com, mm-commits@vger.kernel.org, neilb@suse.de, paulmck@kernel.org, rientjes@google.com, torvalds@linux-foundation.org Subject: [patch 011/166] mm: make it clear that gfp reclaim modifiers are valid only for sleepable allocations Message-ID: <20200407030406.SXeYc0WBG%akpm@linux-foundation.org> In-Reply-To: <20200406200254.a69ebd9e08c4074e41ddebaf@linux-foundation.org> User-Agent: s-nail v14.8.16 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: Michal Hocko Subject: mm: make it clear that gfp reclaim modifiers are valid only for sleepable allocations 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. Link: http://lkml.kernel.org/r/20200403083543.11552-3-mhocko@kernel.org Acked-by: Paul E. McKenney Signed-off-by: Michal Hocko Acked-by: David Rientjes Reviewed-by: Joel Fernandes (Google) Cc: Neil Brown Signed-off-by: Andrew Morton --- include/linux/gfp.h | 2 ++ 1 file changed, 2 insertions(+) --- a/include/linux/gfp.h~mm-make-it-clear-that-gfp-reclaim-modifiers-are-valid-only-for-sleepable-allocations +++ a/include/linux/gfp.h @@ -124,6 +124,8 @@ 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. * _