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=-9.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,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 38291C04AAF for ; Mon, 20 May 2019 04:50:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0A17D20851 for ; Mon, 20 May 2019 04:50:00 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="mI5vScJ4" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730343AbfETEt7 (ORCPT ); Mon, 20 May 2019 00:49:59 -0400 Received: from mail-pf1-f194.google.com ([209.85.210.194]:37891 "EHLO mail-pf1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725372AbfETEt7 (ORCPT ); Mon, 20 May 2019 00:49:59 -0400 Received: by mail-pf1-f194.google.com with SMTP id b76so6575747pfb.5 for ; Sun, 19 May 2019 21:49:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=xkToWfPhUbXUlBSKuzZG3pFF8m3+cgJ3j1xebIaK/EI=; b=mI5vScJ46CfONQKk0BXuJqgqaOpncnnzaBz3sQRykYdFNJRSapviixTBiuyNXhv3Lj IKXhEYu8bwmxqqhsj4jf31vawxOk5hgaSWCzkrl3jSNirETmZA+np4paeXOlSZGefx++ v/lIzQqsOCjlows+Onq9agp+5xzN+dFq06s1M= 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:mime-version :content-transfer-encoding; bh=xkToWfPhUbXUlBSKuzZG3pFF8m3+cgJ3j1xebIaK/EI=; b=MH4xeuI4O/WqxVWN3ID0d++4JtFVS7qbYO3f/WYIWu2FnxR1ngoQ2/6ylo9+YSNojR /8qWtgRVIE2171EzP0OSbNbubSpspiEjl4cTIq6FvUC/DaCZOZDCG9s1BGGUFmj/KQSu BHIDsOEB21aIIfoQ1LuWV8d7wBuCxt9XD/cZdAUXhiajRT0EANFAikTBTIFDlIImTrO8 U8QIomLMYj+KVeKMv9LW89OtgsbTf/YPNpEWWH8fK+LQ6aO0cUcM5qmHRkWCU9CrG6iJ KvBeYTxyoc/O2FZWn4RK9MA6iupmZcWkEM9az4EoOlsSm4C7YPohrCvjEC6uDAcCx2Ye Pswg== X-Gm-Message-State: APjAAAVKw8Yzjht5majKxw+uawlQa0g9Qfr+SWmI643b/b7YNSn3UpeW wh7/snoHHQ092VguOOJq96m05A== X-Google-Smtp-Source: APXvYqwN55gQbIsuZenQKAzA8VBSQYQ1vm8yCPL9giuGjnZvDoaeAZMfk2h4f+nYBl2QObZZzuXkCQ== X-Received: by 2002:a62:ee05:: with SMTP id e5mr76083541pfi.117.1558327798179; Sun, 19 May 2019 21:49:58 -0700 (PDT) Received: from drinkcat2.tpe.corp.google.com ([2401:fa00:1:b:d8b7:33af:adcb:b648]) by smtp.gmail.com with ESMTPSA id 140sm26022608pfw.123.2019.05.19.21.49.55 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sun, 19 May 2019 21:49:57 -0700 (PDT) From: Nicolas Boichat To: Andrew Morton Cc: David Rientjes , Nicolas Boichat , Michal Hocko , Joe Perches , Greg Kroah-Hartman , linux-mm@kvack.org, Akinobu Mita , Pekka Enberg , Mel Gorman , linux-kernel@vger.kernel.org Subject: [PATCH] mm/failslab: By default, do not fail allocations with direct reclaim only Date: Mon, 20 May 2019 12:49:51 +0800 Message-Id: <20190520044951.248096-1-drinkcat@chromium.org> X-Mailer: git-send-email 2.21.0.1020.gf2820cf01a-goog 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 When failslab was originally written, the intention of the "ignore-gfp-wait" flag default value ("N") was to fail GFP_ATOMIC allocations. Those were defined as (__GFP_HIGH), and the code would test for __GFP_WAIT (0x10u). However, since then, __GFP_WAIT was replaced by __GFP_RECLAIM (___GFP_DIRECT_RECLAIM|___GFP_KSWAPD_RECLAIM), and GFP_ATOMIC is now defined as (__GFP_HIGH|__GFP_ATOMIC|__GFP_KSWAPD_RECLAIM). This means that when the flag is false, almost no allocation ever fails (as even GFP_ATOMIC allocations contain __GFP_KSWAPD_RECLAIM). Restore the original intent of the code, by ignoring calls that directly reclaim only (___GFP_DIRECT_RECLAIM), and thus, failing GFP_ATOMIC calls again by default. Fixes: 71baba4b92dc1fa1 ("mm, page_alloc: rename __GFP_WAIT to __GFP_RECLAIM") Signed-off-by: Nicolas Boichat --- mm/failslab.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/mm/failslab.c b/mm/failslab.c index ec5aad211c5be97..33efcb60e633c0a 100644 --- a/mm/failslab.c +++ b/mm/failslab.c @@ -23,7 +23,8 @@ bool __should_failslab(struct kmem_cache *s, gfp_t gfpflags) if (gfpflags & __GFP_NOFAIL) return false; - if (failslab.ignore_gfp_reclaim && (gfpflags & __GFP_RECLAIM)) + if (failslab.ignore_gfp_reclaim && + (gfpflags & ___GFP_DIRECT_RECLAIM)) return false; if (failslab.cache_filter && !(s->flags & SLAB_FAILSLAB)) -- 2.21.0.1020.gf2820cf01a-goog