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=-9.5 required=3.0 tests=DKIM_ADSP_CUSTOM_MED, DKIM_INVALID,DKIM_SIGNED,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, 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 11556C10F27 for ; Mon, 9 Mar 2020 11:32:07 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id AB24120675 for ; Mon, 9 Mar 2020 11:32:06 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="Pa17L/M1" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org AB24120675 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 309216B0003; Mon, 9 Mar 2020 07:32:06 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 2B9B06B0006; Mon, 9 Mar 2020 07:32:06 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 1CF0F6B0007; Mon, 9 Mar 2020 07:32:06 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0186.hostedemail.com [216.40.44.186]) by kanga.kvack.org (Postfix) with ESMTP id 006796B0003 for ; Mon, 9 Mar 2020 07:32:05 -0400 (EDT) Received: from smtpin30.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id A44352490 for ; Mon, 9 Mar 2020 11:32:05 +0000 (UTC) X-FDA: 76575609810.30.mind35_4c73199b8833c X-HE-Tag: mind35_4c73199b8833c X-Filterd-Recvd-Size: 4213 Received: from mail-pj1-f66.google.com (mail-pj1-f66.google.com [209.85.216.66]) by imf04.hostedemail.com (Postfix) with ESMTP for ; Mon, 9 Mar 2020 11:32:05 +0000 (UTC) Received: by mail-pj1-f66.google.com with SMTP id d8so4319400pje.4 for ; Mon, 09 Mar 2020 04:32:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=2k04BRGZHR/QqhuU/poR1nzLbUDIgGLImpsqGHW3wXA=; b=Pa17L/M1pd207BXYQKDDTkKWp/GpfXk1nPhFypxmBIneOeH9L1dMLuE5/gBf5VM0kf cOE+W2F+bpYsALGe2loR9zz+mLeWpA0C3MZwsr5cc98J9HJd9uQHBeFLdKrY1+vUfe/W 4Y4Z/7VDmvtAuSiS4hwDnRterr0QzqcBv1DLceMdJKOH9gJj9wbe4ZTqa3Kn/yo85Qt2 rsgszAMrJYIn3fvdZ58g/pOR0uPrnd2tl6dhcSPhcQWlLkmhEADowpih+IHGLYxzMdC+ cLyMtWQI+85WDgmh3betFQWwtzNR8R0+WleVAH5zsCIoSDxrMCmEhB+crcTY7od13MuM UlIQ== 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=2k04BRGZHR/QqhuU/poR1nzLbUDIgGLImpsqGHW3wXA=; b=gIyjTc85W9U13QcQ/4vQkpeb3EKUB807uHlufFSWQCI4PsgCvTV8jTHX8DSUyuM3Dm DETzRjWJBEd025MT8tLik38s3/A3Hm3PRguXHhRYnTf7Fu6vTbRfrCLsT2ZgbaiAvulc 8NWdMuzMAftrCiTYJ3ydpTXBtfe3NofcbipkcD3nOXMwPuBHmWWzxm12nuVw5m7Tlpjy oTJoiWlHfue15iuaVeFQIrOB6P0+maGhJacV5xcdznfgwmfdN16eP7XfR07LKr6Ih2hA 0xqyy1oFkRGe9D7mHC2nU6CMB1O0Xij9BWAzEu41beiUnqGIrZwCelRJESzwIK5ElIyj EMHA== X-Gm-Message-State: ANhLgQ2xBNadRACzJUtMRNEBN9ztAXKC8RXLuPXBbYo+hvmN2oKSedwH 5IkSNzgEjtXMzdoGYUm7j0A= X-Google-Smtp-Source: ADFU+vun4P1U5QIdL+uosgEY/IG8IA0AO2ZME/p+zXPyYKQVJACmVRZ85s+IKqhyroOdqCGDJr1XgQ== X-Received: by 2002:a17:90b:4903:: with SMTP id kr3mr11658661pjb.3.1583753524257; Mon, 09 Mar 2020 04:32:04 -0700 (PDT) Received: from nutanix.eng.nutanix.com ([192.146.154.247]) by smtp.googlemail.com with ESMTPSA id c15sm19435613pja.30.2020.03.09.04.32.03 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 09 Mar 2020 04:32:03 -0700 (PDT) From: Shaju Abraham X-Google-Original-From: Shaju Abraham To: Cc: akpm@linux-foundation.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, shajunutanix@gmail.com, Shaju Abraham Subject: [PATCH] mm/vmpressure.c: Include GFP_KERNEL flag to vmpressure Date: Mon, 9 Mar 2020 11:31:41 +0000 Message-Id: <20200309113141.167289-1-shaju.abraham@nutanix.com> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable 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: The VM pressure notification flags have excluded GFP_KERNEL with the reasoning that user land will not be able to take any action in case of kernel memory being low. This is not true always. Consider the case of a user land program managing all the huge memory pages. By including GFP_KERNEL flag whenever the kernel memory is low, pressure notification can be send, and the manager process can split huge pages to satisfy kern= el memory requirement. This is a common scanario in cloud. Most of the host memory is reserved as hugepages and can be broken down to small pages on demand. This is done to minimise fragmentation so that Virtual Machine power on will be successful always. Signed-off-by: Shaju Abraham --- mm/vmpressure.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/mm/vmpressure.c b/mm/vmpressure.c index 4bac22fe1aa2..7ccfb3dd8173 100644 --- a/mm/vmpressure.c +++ b/mm/vmpressure.c @@ -253,7 +253,8 @@ void vmpressure(gfp_t gfp, struct mem_cgroup *memcg, = bool tree, * Indirect reclaim (kswapd) sets sc->gfp_mask to GFP_KERNEL, so * we account it too. */ - if (!(gfp & (__GFP_HIGHMEM | __GFP_MOVABLE | __GFP_IO | __GFP_FS))) + if (!(gfp & (__GFP_HIGHMEM | __GFP_MOVABLE | __GFP_IO | + __GFP_FS | GFP_KERNEL))) return; =20 /* --=20 2.20.1