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=-3.8 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 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 CCB87C432C0 for ; Sun, 1 Dec 2019 01:58:10 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 842A22082E for ; Sun, 1 Dec 2019 01:58:10 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="xvapJZuk" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 842A22082E 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 30FF36B0394; Sat, 30 Nov 2019 20:58:10 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 298636B0396; Sat, 30 Nov 2019 20:58:10 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 1AED76B0398; Sat, 30 Nov 2019 20:58:10 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0144.hostedemail.com [216.40.44.144]) by kanga.kvack.org (Postfix) with ESMTP id 00FE76B0394 for ; Sat, 30 Nov 2019 20:58:09 -0500 (EST) Received: from smtpin09.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with SMTP id AAE78180AD817 for ; Sun, 1 Dec 2019 01:58:09 +0000 (UTC) X-FDA: 76214912298.09.alley86_473683458275b X-HE-Tag: alley86_473683458275b X-Filterd-Recvd-Size: 3011 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf13.hostedemail.com (Postfix) with ESMTP for ; Sun, 1 Dec 2019 01:58:09 +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 55430205ED; Sun, 1 Dec 2019 01:58:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1575165488; bh=sKq6bJk0VtGEbufB7B4NAPI6JrHBFNY4zcNOFHjJ54c=; h=Date:From:To:Subject:From; b=xvapJZukyDNs6bpp841u8W3B8WxfUPUnh5sifIMUgSlRE8lBH3UmmO21flhhwxa00 IGsOe7v07qyfpXHZf6uie60/UtCC00KtYiuy60T4s5C82HpNCUy0bm31OnWxxkrd62 dUAM5NaprkfBgHpf+7R9754/fp6vk35L5DhhRt+o= Date: Sat, 30 Nov 2019 17:58:07 -0800 From: akpm@linux-foundation.org To: akpm@linux-foundation.org, hughd@google.com, linux-mm@kvack.org, mhocko@kernel.org, mm-commits@vger.kernel.org, torvalds@linux-foundation.org, yang.shi@linux.alibaba.com Subject: [patch 151/158] mm: shmem: use proper gfp flags for shmem_writepage() Message-ID: <20191201015807.hMeXscL91%akpm@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: Yang Shi Subject: mm: shmem: use proper gfp flags for shmem_writepage() The shmem_writepage() uses GFP_ATOMIC to allocate swap cache. GFP_ATOMIC used to mean __GFP_HIGH, but now it means __GFP_HIGH | __GFP_ATOMIC | __GFP_KSWAPD_RECLAIM. However, shmem_writepage() should write out to swap only in response to memory pressure, so __GFP_KSWAPD_RECLAIM looks useless since the caller may be kswapd itself or in direct reclaim already. In addition, XArray node allocations from PF_MEMALLOC contexts could completely exhaust the page allocator, __GFP_NOMEMALLOC stops emergency reserves from being allocated. Here just copy the gfp flags used by add_to_swap(). Hugh: "a cleanup to make the two calls look the same when they don't need to be different (whereas the call from __read_swap_cache_async() rightly uses a lower priority gfp)". Link: http://lkml.kernel.org/r/1572991351-86061-1-git-send-email-yang.shi@linux.alibaba.com Signed-off-by: Yang Shi Acked-by: Hugh Dickins Cc: Michal Hocko Signed-off-by: Andrew Morton --- mm/shmem.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/mm/shmem.c~mm-shmem-use-proper-gfp-flags-for-shmem_writepage +++ a/mm/shmem.c @@ -1369,7 +1369,8 @@ static int shmem_writepage(struct page * if (list_empty(&info->swaplist)) list_add(&info->swaplist, &shmem_swaplist); - if (add_to_swap_cache(page, swap, GFP_ATOMIC) == 0) { + if (add_to_swap_cache(page, swap, + __GFP_HIGH | __GFP_NOMEMALLOC | __GFP_NOWARN) == 0) { spin_lock_irq(&info->lock); shmem_recalc_inode(inode); info->swapped++; _