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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 83722C43334 for ; Mon, 6 Jun 2022 19:41:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232343AbiFFTlJ (ORCPT ); Mon, 6 Jun 2022 15:41:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60426 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229665AbiFFTlI (ORCPT ); Mon, 6 Jun 2022 15:41:08 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BF5435FC8 for ; Mon, 6 Jun 2022 12:41:03 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 67DBEB81B41 for ; Mon, 6 Jun 2022 19:41:02 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 08726C34115; Mon, 6 Jun 2022 19:41:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1654544461; bh=pdrhTRCcVisd6AWwys1iQii8iB44QzWAeT+yvNh8J5I=; h=Date:To:From:Subject:From; b=vUBQjLLnQGUaMspU8f/2pt2ZHGkJNEPSvd4I1U1MAhlAJ+R0+rYl9pSR4Cu6+mFHO weu2CwuwDdzW2DLqzzRhcrwQDs75qGA/dKPGyyyD5qKLg/grtE+YUMaYzFb10bqqZy kfRVII7orCNOmi+p2lq1wqV0tEvrtv0RhdBP5IEo= Date: Mon, 06 Jun 2022 12:41:00 -0700 To: mm-commits@vger.kernel.org, zhengliang6@huawei.com, yi.zhang@huawei.com, Xiongwei.Song@windriver.com, willy@infradead.org, phillip@squashfs.org.uk, m.szyprowski@samsung.com, miaoxie@huawei.com, houtao1@huawei.com, hsinyi@chromium.org, akpm@linux-foundation.org From: Andrew Morton Subject: + revert-squashfs-provide-backing_dev_info-in-order-to-disable-read-ahead.patch added to mm-nonmm-unstable branch Message-Id: <20220606194101.08726C34115@smtp.kernel.org> Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org The patch titled Subject: Revert "squashfs: provide backing_dev_info in order to disable read-ahead" has been added to the -mm mm-nonmm-unstable branch. Its filename is revert-squashfs-provide-backing_dev_info-in-order-to-disable-read-ahead.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/revert-squashfs-provide-backing_dev_info-in-order-to-disable-read-ahead.patch This patch will later appear in the mm-nonmm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Hsin-Yi Wang Subject: Revert "squashfs: provide backing_dev_info in order to disable read-ahead" Date: Mon, 6 Jun 2022 23:03:03 +0800 Patch series "Implement readahead for squashfs", v5. Commit c1f6925e1091("mm: put readahead pages in cache earlier") requires fs to implement readahead callback. Otherwise there will be a performance regression. Commit 9eec1d897139("squashfs: provide backing_dev_info in order to disable read-ahead") mitigates the performance drop issue for squashfs by closing readahead for it. This series implements readahead callback for squashfs. The previous discussion are in [1] and [2]. [1] https://lore.kernel.org/all/CAJMQK-g9G6KQmH-V=BRGX0swZji9Wxe_2c7ht-MMAapdFy2pXw@mail.gmail.com/T/ [2] https://lore.kernel.org/linux-mm/Yn5Yij9pRPCzDozt@casper.infradead.org/t/#m4af4473b94f98a4996cb11756b633a07e5e059d1 This patch (of 3): This reverts commit 9eec1d897139e5d ("squashfs: provide backing_dev_info in order to disable read-ahead"). Revert closing the readahead to squashfs since the readahead callback for squashfs is implemented. Link: https://lkml.kernel.org/r/20220606150305.1883410-1-hsinyi@chromium.org Link: https://lkml.kernel.org/r/20220606150305.1883410-2-hsinyi@chromium.org Signed-off-by: Hsin-Yi Wang Suggested-by: Xiongwei Song Cc: Phillip Lougher Cc: Matthew Wilcox Cc: Marek Szyprowski Cc: Zheng Liang Cc: Zhang Yi Cc: Hou Tao Cc: Miao Xie Signed-off-by: Andrew Morton --- fs/squashfs/super.c | 33 --------------------------------- 1 file changed, 33 deletions(-) --- a/fs/squashfs/super.c~revert-squashfs-provide-backing_dev_info-in-order-to-disable-read-ahead +++ a/fs/squashfs/super.c @@ -29,7 +29,6 @@ #include #include #include -#include #include "squashfs_fs.h" #include "squashfs_fs_sb.h" @@ -113,24 +112,6 @@ static const struct squashfs_decompresso return decompressor; } -static int squashfs_bdi_init(struct super_block *sb) -{ - int err; - unsigned int major = MAJOR(sb->s_dev); - unsigned int minor = MINOR(sb->s_dev); - - bdi_put(sb->s_bdi); - sb->s_bdi = &noop_backing_dev_info; - - err = super_setup_bdi_name(sb, "squashfs_%u_%u", major, minor); - if (err) - return err; - - sb->s_bdi->ra_pages = 0; - sb->s_bdi->io_pages = 0; - - return 0; -} static int squashfs_fill_super(struct super_block *sb, struct fs_context *fc) { @@ -146,20 +127,6 @@ static int squashfs_fill_super(struct su TRACE("Entered squashfs_fill_superblock\n"); - /* - * squashfs provides 'backing_dev_info' in order to disable read-ahead. For - * squashfs, I/O is not deferred, it is done immediately in read_folio, - * which means the user would always have to wait their own I/O. So the effect - * of readahead is very weak for squashfs. squashfs_bdi_init will set - * sb->s_bdi->ra_pages and sb->s_bdi->io_pages to 0 and close readahead for - * squashfs. - */ - err = squashfs_bdi_init(sb); - if (err) { - errorf(fc, "squashfs init bdi failed"); - return err; - } - sb->s_fs_info = kzalloc(sizeof(*msblk), GFP_KERNEL); if (sb->s_fs_info == NULL) { ERROR("Failed to allocate squashfs_sb_info\n"); _ Patches currently in -mm which might be from hsinyi@chromium.org are revert-squashfs-provide-backing_dev_info-in-order-to-disable-read-ahead.patch squashfs-implement-readahead.patch