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,USER_AGENT_GIT autolearn=unavailable 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 70857C55197 for ; Fri, 24 Apr 2020 12:24:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5074A21775 for ; Fri, 24 Apr 2020 12:24:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587731082; bh=DHDc8HltG1BdWiLHKwuKbNTHzHVBSNJSqnUSXAbGIkY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=Znhk1W+YyQvambA6TA1dReBDG+aIPU7IbzeaPxNiga8ipIcpygMOH4WlFRbc7qs+k G9xOOskOyn0YP6TEPFtuizneacM4Yf0yOYsW2xUeNENBNZRmjceV5p0UHkBx6yQWNL 9gDfnTvVcotlmM2vLEX5LfLo9tieCurERMs00Awg= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728501AbgDXMYl (ORCPT ); Fri, 24 Apr 2020 08:24:41 -0400 Received: from mail.kernel.org ([198.145.29.99]:55370 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728477AbgDXMYi (ORCPT ); Fri, 24 Apr 2020 08:24:38 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 9C21920700; Fri, 24 Apr 2020 12:24:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587731077; bh=DHDc8HltG1BdWiLHKwuKbNTHzHVBSNJSqnUSXAbGIkY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ZmCBCtmqZYFv9jo52Njgf/8cM5336w1GJDY6bfo0NPzIX8sQRYkq9ODyTZlCwUJqS SUYhtyw9lsAgpCOz4VAt9lLGiEkhk5+DzxHdPGPQvm/f3cSiF+aYDxZjsCpyk5yZbT TN+9MgV7kENYUapNUWjsqfg2gM0yAfQy41nidSu0= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Roman Gushchin , Andreas Dilger , Theodore Ts'o , Sasha Levin , linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org Subject: [PATCH AUTOSEL 4.14 14/21] ext4: use non-movable memory for superblock readahead Date: Fri, 24 Apr 2020 08:24:12 -0400 Message-Id: <20200424122419.10648-14-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200424122419.10648-1-sashal@kernel.org> References: <20200424122419.10648-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Roman Gushchin [ Upstream commit d87f639258a6a5980183f11876c884931ad93da2 ] Since commit a8ac900b8163 ("ext4: use non-movable memory for the superblock") buffers for ext4 superblock were allocated using the sb_bread_unmovable() helper which allocated buffer heads out of non-movable memory blocks. It was necessarily to not block page migrations and do not cause cma allocation failures. However commit 85c8f176a611 ("ext4: preload block group descriptors") broke this by introducing pre-reading of the ext4 superblock. The problem is that __breadahead() is using __getblk() underneath, which allocates buffer heads out of movable memory. It resulted in page migration failures I've seen on a machine with an ext4 partition and a preallocated cma area. Fix this by introducing sb_breadahead_unmovable() and __breadahead_gfp() helpers which use non-movable memory for buffer head allocations and use them for the ext4 superblock readahead. Reviewed-by: Andreas Dilger Fixes: 85c8f176a611 ("ext4: preload block group descriptors") Signed-off-by: Roman Gushchin Link: https://lore.kernel.org/r/20200229001411.128010-1-guro@fb.com Signed-off-by: Theodore Ts'o Signed-off-by: Sasha Levin --- fs/buffer.c | 11 +++++++++++ fs/ext4/inode.c | 2 +- fs/ext4/super.c | 2 +- include/linux/buffer_head.h | 8 ++++++++ 4 files changed, 21 insertions(+), 2 deletions(-) diff --git a/fs/buffer.c b/fs/buffer.c index bdca7b10e239b..cae7f24a0410e 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -1398,6 +1398,17 @@ void __breadahead(struct block_device *bdev, sector_t block, unsigned size) } EXPORT_SYMBOL(__breadahead); +void __breadahead_gfp(struct block_device *bdev, sector_t block, unsigned size, + gfp_t gfp) +{ + struct buffer_head *bh = __getblk_gfp(bdev, block, size, gfp); + if (likely(bh)) { + ll_rw_block(REQ_OP_READ, REQ_RAHEAD, 1, &bh); + brelse(bh); + } +} +EXPORT_SYMBOL(__breadahead_gfp); + /** * __bread_gfp() - reads a specified block and returns the bh * @bdev: the block_device to read from diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 10838b28c5bbd..c8a1c68c33ae5 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -4593,7 +4593,7 @@ static int __ext4_get_inode_loc(struct inode *inode, if (end > table) end = table; while (b <= end) - sb_breadahead(sb, b++); + sb_breadahead_unmovable(sb, b++); } /* diff --git a/fs/ext4/super.c b/fs/ext4/super.c index f5646bcad7702..074b9d43e24d8 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -4145,7 +4145,7 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) /* Pre-read the descriptors into the buffer cache */ for (i = 0; i < db_count; i++) { block = descriptor_loc(sb, logical_sb_block, i); - sb_breadahead(sb, block); + sb_breadahead_unmovable(sb, block); } for (i = 0; i < db_count; i++) { diff --git a/include/linux/buffer_head.h b/include/linux/buffer_head.h index afa37f807f12c..2e1077ea77db0 100644 --- a/include/linux/buffer_head.h +++ b/include/linux/buffer_head.h @@ -187,6 +187,8 @@ struct buffer_head *__getblk_gfp(struct block_device *bdev, sector_t block, void __brelse(struct buffer_head *); void __bforget(struct buffer_head *); void __breadahead(struct block_device *, sector_t block, unsigned int size); +void __breadahead_gfp(struct block_device *, sector_t block, unsigned int size, + gfp_t gfp); struct buffer_head *__bread_gfp(struct block_device *, sector_t block, unsigned size, gfp_t gfp); void invalidate_bh_lrus(void); @@ -319,6 +321,12 @@ sb_breadahead(struct super_block *sb, sector_t block) __breadahead(sb->s_bdev, block, sb->s_blocksize); } +static inline void +sb_breadahead_unmovable(struct super_block *sb, sector_t block) +{ + __breadahead_gfp(sb->s_bdev, block, sb->s_blocksize, 0); +} + static inline struct buffer_head * sb_getblk(struct super_block *sb, sector_t block) { -- 2.20.1