From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out30-99.freemail.mail.aliyun.com (out30-99.freemail.mail.aliyun.com [115.124.30.99]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 23E492DCF61; Wed, 14 Jan 2026 14:56:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=115.124.30.99 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768402621; cv=none; b=Klt0ApaqnpBWk5BGAJ7o9eMyu2L9ocpacRvDRfOSDEFCbmndzss2IIjdNeos8QZwP2Lig3giUSSmbqjvGQ619sRXAU7S9oOkJZOUQvdOiwphEiGuVn3X8+yh88w+El1zwOzIOmFiEQPg18QSNa3li2aSo1jPv5lMrYQTme2g09U= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768402621; c=relaxed/simple; bh=2drGeW3rb/glmM47EtWUS4WA1UF6n3Ks9yUbhmLB21A=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=UXRW8EcA7vlq8RcPD2EQe1RlgwV641k88q6m2tXsULVEBKxho2EPAQybekYpSg2OPlgobnjxZ/Ph705pAi0WGOXWQeeck7xB52+1Ux0YYIddHG3iVBP5gKFDxq1gKjrP0GqXxSjSAzWk+SOKIYvTNC8ldzlUvmfjSXGneqtpmcc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com; spf=pass smtp.mailfrom=linux.alibaba.com; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b=ZF2n5HHl; arc=none smtp.client-ip=115.124.30.99 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b="ZF2n5HHl" DKIM-Signature:v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1768402617; h=Message-ID:Date:MIME-Version:Subject:To:From:Content-Type; bh=tKEiYyztp7rnSuLNkwLOusLX/k6l5Kw33OzxJI4VSF0=; b=ZF2n5HHlmXu8jo66pugRCSYjLvLGz11mR8vTBo+AeT7f7KjwLmwywbUp+WViRoZwh6HnxD2FNMYtwBz8yZkQwVbw5eYuKyZH9CmlI1l5fXS2Oqsw+wt6lkPUw1R1GIcuky+02U/kXqXNVYZH3hkca/umifbK/M6UAdECC9noLFQ= Received: from 30.180.182.138(mailfrom:hsiangkao@linux.alibaba.com fp:SMTPD_---0Wx2jw0M_1768402294 cluster:ay36) by smtp.aliyun-inc.com; Wed, 14 Jan 2026 22:51:34 +0800 Message-ID: <2d33cc2f-8188-4e62-b0be-bf985237bf24@linux.alibaba.com> Date: Wed, 14 Jan 2026 22:51:33 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v14 08/10] erofs: support unencoded inodes for page cache share To: Hongbo Li Cc: djwong@kernel.org, amir73il@gmail.com, hch@lst.de, linux-fsdevel@vger.kernel.org, linux-erofs@lists.ozlabs.org, linux-kernel@vger.kernel.org, Chao Yu , Christian Brauner References: <20260109102856.598531-1-lihongbo22@huawei.com> <20260109102856.598531-9-lihongbo22@huawei.com> From: Gao Xiang In-Reply-To: <20260109102856.598531-9-lihongbo22@huawei.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 2026/1/9 18:28, Hongbo Li wrote: > This patch adds inode page cache sharing functionality for unencoded > files. > > I conducted experiments in the container environment. Below is the > memory usage for reading all files in two different minor versions > of container images: > > +-------------------+------------------+-------------+---------------+ > | Image | Page Cache Share | Memory (MB) | Memory | > | | | | Reduction (%) | > +-------------------+------------------+-------------+---------------+ > | | No | 241 | - | > | redis +------------------+-------------+---------------+ > | 7.2.4 & 7.2.5 | Yes | 163 | 33% | > +-------------------+------------------+-------------+---------------+ > | | No | 872 | - | > | postgres +------------------+-------------+---------------+ > | 16.1 & 16.2 | Yes | 630 | 28% | > +-------------------+------------------+-------------+---------------+ > | | No | 2771 | - | > | tensorflow +------------------+-------------+---------------+ > | 2.11.0 & 2.11.1 | Yes | 2340 | 16% | > +-------------------+------------------+-------------+---------------+ > | | No | 926 | - | > | mysql +------------------+-------------+---------------+ > | 8.0.11 & 8.0.12 | Yes | 735 | 21% | > +-------------------+------------------+-------------+---------------+ > | | No | 390 | - | > | nginx +------------------+-------------+---------------+ > | 7.2.4 & 7.2.5 | Yes | 219 | 44% | > +-------------------+------------------+-------------+---------------+ > | tomcat | No | 924 | - | > | 10.1.25 & 10.1.26 +------------------+-------------+---------------+ > | | Yes | 474 | 49% | > +-------------------+------------------+-------------+---------------+ > > Additionally, the table below shows the runtime memory usage of the > container: > > +-------------------+------------------+-------------+---------------+ > | Image | Page Cache Share | Memory (MB) | Memory | > | | | | Reduction (%) | > +-------------------+------------------+-------------+---------------+ > | | No | 35 | - | > | redis +------------------+-------------+---------------+ > | 7.2.4 & 7.2.5 | Yes | 28 | 20% | > +-------------------+------------------+-------------+---------------+ > | | No | 149 | - | > | postgres +------------------+-------------+---------------+ > | 16.1 & 16.2 | Yes | 95 | 37% | > +-------------------+------------------+-------------+---------------+ > | | No | 1028 | - | > | tensorflow +------------------+-------------+---------------+ > | 2.11.0 & 2.11.1 | Yes | 930 | 10% | > +-------------------+------------------+-------------+---------------+ > | | No | 155 | - | > | mysql +------------------+-------------+---------------+ > | 8.0.11 & 8.0.12 | Yes | 132 | 15% | > +-------------------+------------------+-------------+---------------+ > | | No | 25 | - | > | nginx +------------------+-------------+---------------+ > | 7.2.4 & 7.2.5 | Yes | 20 | 20% | > +-------------------+------------------+-------------+---------------+ > | tomcat | No | 186 | - | > | 10.1.25 & 10.1.26 +------------------+-------------+---------------+ > | | Yes | 98 | 48% | > +-------------------+------------------+-------------+---------------+ > > Co-developed-by: Hongzhen Luo > Signed-off-by: Hongzhen Luo > Signed-off-by: Hongbo Li > --- > fs/erofs/data.c | 32 +++++++++++++++++++++++--------- > fs/erofs/fileio.c | 25 ++++++++++++++++--------- > fs/erofs/inode.c | 2 ++ > fs/erofs/internal.h | 6 ++++++ > fs/erofs/ishare.c | 34 ++++++++++++++++++++++++++++++++++ > fs/erofs/zdata.c | 2 +- > include/trace/events/erofs.h | 10 +++++----- > 7 files changed, 87 insertions(+), 24 deletions(-) > > diff --git a/fs/erofs/data.c b/fs/erofs/data.c > index 71e23d91123d..7bbd94781170 100644 > --- a/fs/erofs/data.c > +++ b/fs/erofs/data.c > @@ -269,6 +269,7 @@ void erofs_onlinefolio_end(struct folio *folio, int err, bool dirty) > struct erofs_iomap_iter_ctx { > struct page *page; > void *base; > + struct inode *realinode; > }; > > static int erofs_iomap_begin(struct inode *inode, loff_t offset, loff_t length, > @@ -276,14 +277,15 @@ static int erofs_iomap_begin(struct inode *inode, loff_t offset, loff_t length, > { > struct iomap_iter *iter = container_of(iomap, struct iomap_iter, iomap); > struct erofs_iomap_iter_ctx *ctx = iter->private; > - struct super_block *sb = inode->i_sb; > + struct inode *realinode = ctx ? ctx->realinode : inode; > + struct super_block *sb = realinode->i_sb; > struct erofs_map_blocks map; > struct erofs_map_dev mdev; > int ret; > > map.m_la = offset; > map.m_llen = length; > - ret = erofs_map_blocks(inode, &map); > + ret = erofs_map_blocks(realinode, &map); > if (ret < 0) > return ret; > > @@ -296,7 +298,7 @@ static int erofs_iomap_begin(struct inode *inode, loff_t offset, loff_t length, > return 0; > } > > - if (!(map.m_flags & EROFS_MAP_META) || !erofs_inode_in_metabox(inode)) { > + if (!(map.m_flags & EROFS_MAP_META) || !erofs_inode_in_metabox(realinode)) { > mdev = (struct erofs_map_dev) { > .m_deviceid = map.m_deviceid, > .m_pa = map.m_pa, > @@ -322,7 +324,7 @@ static int erofs_iomap_begin(struct inode *inode, loff_t offset, loff_t length, > void *ptr; > > ptr = erofs_read_metabuf(&buf, sb, map.m_pa, > - erofs_inode_in_metabox(inode)); > + erofs_inode_in_metabox(realinode)); > if (IS_ERR(ptr)) > return PTR_ERR(ptr); > iomap->inline_data = ptr; > @@ -383,11 +385,16 @@ static int erofs_read_folio(struct file *file, struct folio *folio) > .ops = &iomap_bio_read_ops, > .cur_folio = folio, > }; > - struct erofs_iomap_iter_ctx iter_ctx = {}; > + bool need_iput; > + struct erofs_iomap_iter_ctx iter_ctx = { > + .realinode = erofs_real_inode(folio_inode(folio), &need_iput), > + }; > > - trace_erofs_read_folio(folio, true); > + trace_erofs_read_folio(iter_ctx.realinode, folio, true); > > iomap_read_folio(&erofs_iomap_ops, &read_ctx, &iter_ctx); > + if (need_iput) > + iput(iter_ctx.realinode); > return 0; > } > > @@ -397,12 +404,17 @@ static void erofs_readahead(struct readahead_control *rac) > .ops = &iomap_bio_read_ops, > .rac = rac, > }; > - struct erofs_iomap_iter_ctx iter_ctx = {}; > + bool need_iput; > + struct erofs_iomap_iter_ctx iter_ctx = { > + .realinode = erofs_real_inode(rac->mapping->host, &need_iput), > + }; > > - trace_erofs_readahead(rac->mapping->host, readahead_index(rac), > + trace_erofs_readahead(iter_ctx.realinode, readahead_index(rac), > readahead_count(rac), true); Is it possible to add a commit to update the tracepoints to add the new realinode first? Also please fix the indentation in that commit together. > > iomap_readahead(&erofs_iomap_ops, &read_ctx, &iter_ctx); > + if (need_iput) > + iput(iter_ctx.realinode); > } > > static sector_t erofs_bmap(struct address_space *mapping, sector_t block) > @@ -423,7 +435,9 @@ static ssize_t erofs_file_read_iter(struct kiocb *iocb, struct iov_iter *to) > return dax_iomap_rw(iocb, to, &erofs_iomap_ops); > #endif > if ((iocb->ki_flags & IOCB_DIRECT) && inode->i_sb->s_bdev) { > - struct erofs_iomap_iter_ctx iter_ctx = {}; > + struct erofs_iomap_iter_ctx iter_ctx = { > + .realinode = inode, > + }; > > return iomap_dio_rw(iocb, to, &erofs_iomap_ops, > NULL, 0, &iter_ctx, 0); > diff --git a/fs/erofs/fileio.c b/fs/erofs/fileio.c > index 932e8b353ba1..c1d0081609dc 100644 > --- a/fs/erofs/fileio.c > +++ b/fs/erofs/fileio.c > @@ -88,9 +88,9 @@ void erofs_fileio_submit_bio(struct bio *bio) > bio)); > } > > -static int erofs_fileio_scan_folio(struct erofs_fileio *io, struct folio *folio) > +static int erofs_fileio_scan_folio(struct erofs_fileio *io, > + struct inode *inode, struct folio *folio) > { > - struct inode *inode = folio_inode(folio); > struct erofs_map_blocks *map = &io->map; > unsigned int cur = 0, end = folio_size(folio), len, attached = 0; > loff_t pos = folio_pos(folio), ofs; > @@ -158,31 +158,38 @@ static int erofs_fileio_scan_folio(struct erofs_fileio *io, struct folio *folio) > > static int erofs_fileio_read_folio(struct file *file, struct folio *folio) > { > + bool need_iput; > + struct inode *realinode = erofs_real_inode(folio_inode(folio), &need_iput); > struct erofs_fileio io = {}; > int err; > > - trace_erofs_read_folio(folio, true); > - err = erofs_fileio_scan_folio(&io, folio); > + trace_erofs_read_folio(realinode, folio, true); > + err = erofs_fileio_scan_folio(&io, realinode, folio); > erofs_fileio_rq_submit(io.rq); > + if (need_iput) > + iput(realinode); > return err; > } > > static void erofs_fileio_readahead(struct readahead_control *rac) > { > - struct inode *inode = rac->mapping->host; > + bool need_iput; > + struct inode *realinode = erofs_real_inode(rac->mapping->host, &need_iput); > struct erofs_fileio io = {}; > struct folio *folio; > int err; > > - trace_erofs_readahead(inode, readahead_index(rac), > + trace_erofs_readahead(realinode, readahead_index(rac), > readahead_count(rac), true); > while ((folio = readahead_folio(rac))) { > - err = erofs_fileio_scan_folio(&io, folio); > + err = erofs_fileio_scan_folio(&io, realinode, folio); > if (err && err != -EINTR) > - erofs_err(inode->i_sb, "readahead error at folio %lu @ nid %llu", > - folio->index, EROFS_I(inode)->nid); > + erofs_err(realinode->i_sb, "readahead error at folio %lu @ nid %llu", > + folio->index, EROFS_I(realinode)->nid); > } > erofs_fileio_rq_submit(io.rq); > + if (need_iput) > + iput(realinode); > } > > const struct address_space_operations erofs_fileio_aops = { > diff --git a/fs/erofs/inode.c b/fs/erofs/inode.c > index bce98c845a18..52179b706b5b 100644 > --- a/fs/erofs/inode.c > +++ b/fs/erofs/inode.c > @@ -215,6 +215,8 @@ static int erofs_fill_inode(struct inode *inode) > case S_IFREG: > inode->i_op = &erofs_generic_iops; > inode->i_fop = &erofs_file_fops; > + if (erofs_ishare_fill_inode(inode)) > + inode->i_fop = &erofs_ishare_fops; inode->i_fop = erofs_ishare_fill_inode(inode) ? &erofs_ishare_fops : &erofs_file_fops; Otherwise it looks good to me. Thanks, Gao Xiang