From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out30-124.freemail.mail.aliyun.com (out30-124.freemail.mail.aliyun.com [115.124.30.124]) (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 93280337118 for ; Tue, 21 Oct 2025 13:01:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=115.124.30.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761051706; cv=none; b=SXyXDm7IhwsKf716x76uGoE01Oe2+bO++j6zWUnlJ747TQRbgxqj8vmtgt1L0VxPkRmlD9xTQ3tNQCkJs8SQsm6MvayyECFO8chQOUIvlKrMZbt4ciPed/eKEySc/JNOnu+EtmauRP2xzarL8wDHbh6yvz0ts3BeyBKFs5fnM14= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761051706; c=relaxed/simple; bh=Ks8XgcKXndycUbTm+Uu8wrGFfOzPcCjYJzyE9/UppCM=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=CLjL/tDL81Nn2412tC/dIewxX4rQ3dp877L54+sJn836tofK6SAvQD/weI3Mcj//RDLu3lGCj1WHJujhGF+D4FV1/ETMCXOYokXwn23Q85H4W8a8IJUw5KLbwcs7EOpaXm4+FVliD9GHFa0KIrz+3uMHmbgg4mYCqd7X8t5lFHc= 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=f6cd+2xw; arc=none smtp.client-ip=115.124.30.124 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="f6cd+2xw" DKIM-Signature:v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1761051700; h=Message-ID:Date:MIME-Version:Subject:To:From:Content-Type; bh=HMOIo9bj01WGBspEBVjROmQ/WIesyC/CiLx2+1Px6os=; b=f6cd+2xwsXVPbNBOvwP6vVi2Fh28Qu3ogj031tAn3CO1qqbwpOekVPJKINGg7fP8p2HFLu6FSgbJv4qnsO3S17WgQ9PYM+aGNUyNMBfDzKVQs0xNKW2+C9RpntRyzRcnLare3AaUqE9qf9000PAFg2RgM7ak+nZxR+6GBEGhPiA= Received: from 30.180.79.37(mailfrom:hsiangkao@linux.alibaba.com fp:SMTPD_---0WqjB-52_1761051698 cluster:ay36) by smtp.aliyun-inc.com; Tue, 21 Oct 2025 21:01:39 +0800 Message-ID: <96569039-1d93-45bc-a0e0-631b71bbb41f@linux.alibaba.com> Date: Tue, 21 Oct 2025 21:01:38 +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 RFC v7 5/7] erofs: support unencoded inodes for page cache share To: Hongbo Li , brauner@kernel.org Cc: linux-erofs@lists.ozlabs.org, linux-kernel@vger.kernel.org, Chao Yu , Hongzhen Luo References: <20251021104815.70662-1-lihongbo22@huawei.com> <20251021104815.70662-6-lihongbo22@huawei.com> From: Gao Xiang In-Reply-To: <20251021104815.70662-6-lihongbo22@huawei.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 2025/10/21 18:48, Hongbo Li wrote: > From: Hongzhen Luo > > 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% | > +-------------------+------------------+-------------+---------------+ > > Signed-off-by: Hongzhen Luo > [hongbo: forward port, minor fixes and cleanup] > Signed-off-by: Hongbo Li > --- > fs/erofs/data.c | 81 ++++++++++++++++++++++++++++++++++++++----- > fs/erofs/inode.c | 5 +++ > fs/erofs/internal.h | 4 +++ > fs/erofs/ishare.c | 83 +++++++++++++++++++++++++++++++++++++++++++++ > fs/erofs/ishare.h | 18 ++++++++++ > fs/erofs/super.c | 7 ++++ > 6 files changed, 190 insertions(+), 8 deletions(-) > > diff --git a/fs/erofs/data.c b/fs/erofs/data.c > index 8ca29962a3dd..438d43c959aa 100644 > --- a/fs/erofs/data.c > +++ b/fs/erofs/data.c > @@ -5,6 +5,7 @@ > * Copyright (C) 2021, Alibaba Cloud > */ > #include "internal.h" > +#include "ishare.h" > #include > #include > > @@ -266,25 +267,55 @@ void erofs_onlinefolio_end(struct folio *folio, int err, bool dirty) > folio_end_read(folio, !(v & BIT(EROFS_ONLINEFOLIO_EIO))); > } > > +struct erofs_iomap { > + void *base; > + struct inode *realinode; > +}; > + > static int erofs_iomap_begin(struct inode *inode, loff_t offset, loff_t length, > unsigned int flags, struct iomap *iomap, struct iomap *srcmap) > { > int ret; > - struct super_block *sb = inode->i_sb; > + struct super_block *sb; > struct erofs_map_blocks map; > struct erofs_map_dev mdev; > + struct inode *realinode = inode; > + struct erofs_iomap *erofs_iomap; > + bool is_ishare = erofs_is_ishare_inode(inode); > + > + if (is_ishare) { > + if (!iomap->private) { I tend to pass in `iomap->private` and allocate on disk as I mentioned in https://lore.kernel.org/r/20250829235627.4053234-14-joannelkoong@gmail.com to avoid unnecessary kzalloc. Thanks, Gao Xiang > + erofs_iomap = kzalloc(sizeof(*erofs_iomap), > + GFP_KERNEL); > + if (!erofs_iomap) > + return -ENOMEM; > + erofs_iomap->realinode = erofs_ishare_iget(inode); > + if (!erofs_iomap->realinode) { > + kfree(erofs_iomap); > + return -EINVAL; > + } > + iomap->private = erofs_iomap; > + } > + erofs_iomap = iomap->private; > + realinode = erofs_iomap->realinode; > + } > > + sb = realinode->i_sb; > 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; > > iomap->offset = map.m_la; > iomap->length = map.m_llen; > iomap->flags = 0; > - iomap->private = NULL; > iomap->addr = IOMAP_NULL_ADDR; > + > + if (is_ishare) > + erofs_iomap->base = NULL; > + else > + iomap->private = NULL; > if (!(map.m_flags & EROFS_MAP_MAPPED)) { > iomap->type = IOMAP_HOLE; > return 0; > @@ -318,7 +349,10 @@ static int erofs_iomap_begin(struct inode *inode, loff_t offset, loff_t length, > if (IS_ERR(ptr)) > return PTR_ERR(ptr); > iomap->inline_data = ptr; > - iomap->private = buf.base; > + if (is_ishare) > + erofs_iomap->base = buf.base; > + else > + iomap->private = buf.base; > } else { > iomap->type = IOMAP_MAPPED; > } > @@ -328,7 +362,17 @@ static int erofs_iomap_begin(struct inode *inode, loff_t offset, loff_t length, > static int erofs_iomap_end(struct inode *inode, loff_t pos, loff_t length, > ssize_t written, unsigned int flags, struct iomap *iomap) > { > - void *ptr = iomap->private; > + struct erofs_iomap *erofs_iomap; > + bool is_ishare; > + void *ptr; > + > + is_ishare = erofs_is_ishare_inode(inode); > + if (is_ishare) { > + erofs_iomap = iomap->private; > + ptr = erofs_iomap->base; > + } else { > + ptr = iomap->private; > + } > > if (ptr) { > struct erofs_buf buf = { > @@ -341,6 +385,12 @@ static int erofs_iomap_end(struct inode *inode, loff_t pos, loff_t length, > } else { > DBG_BUGON(iomap->type == IOMAP_INLINE); > } > + > + if (is_ishare) { > + erofs_ishare_iput(erofs_iomap->realinode); > + kfree(erofs_iomap); > + iomap->private = NULL; > + } > return written; > } > > @@ -369,17 +419,32 @@ int erofs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, > */ > static int erofs_read_folio(struct file *file, struct folio *folio) > { > + struct erofs_read_ctx rdctx = { > + .file = file, > + .inode = folio_inode(folio), > + }; > + int ret; > + > + erofs_read_begin(&rdctx); > + ret = iomap_read_folio(folio, &erofs_iomap_ops); > + erofs_read_end(&rdctx); > trace_erofs_read_folio(folio, true); > > - return iomap_read_folio(folio, &erofs_iomap_ops); > + return ret; > } > > static void erofs_readahead(struct readahead_control *rac) > { > + struct erofs_read_ctx rdctx = { > + .file = rac->file, > + .inode = rac->mapping->host, > + }; > + > + erofs_read_begin(&rdctx); > + iomap_readahead(rac, &erofs_iomap_ops); > + erofs_read_end(&rdctx); > trace_erofs_readahead(rac->mapping->host, readahead_index(rac), > readahead_count(rac), true); > - > - return iomap_readahead(rac, &erofs_iomap_ops); > } > > static sector_t erofs_bmap(struct address_space *mapping, sector_t block) > diff --git a/fs/erofs/inode.c b/fs/erofs/inode.c > index cb780c095d28..fe45e6c18f8e 100644 > --- a/fs/erofs/inode.c > +++ b/fs/erofs/inode.c > @@ -5,6 +5,7 @@ > * Copyright (C) 2021, Alibaba Cloud > */ > #include "xattr.h" > +#include "ishare.h" > #include > #include > > @@ -215,6 +216,10 @@ static int erofs_fill_inode(struct inode *inode) > case S_IFREG: > inode->i_op = &erofs_generic_iops; > inode->i_fop = &erofs_file_fops; > +#ifdef CONFIG_EROFS_FS_INODE_SHARE > + if (erofs_ishare_fill_inode(inode)) > + inode->i_fop = &erofs_ishare_fops; > +#endif > break; > case S_IFDIR: > inode->i_op = &erofs_dir_iops; > diff --git a/fs/erofs/internal.h b/fs/erofs/internal.h > index 158bda6ba784..9ce6e5753978 100644 > --- a/fs/erofs/internal.h > +++ b/fs/erofs/internal.h > @@ -322,11 +322,15 @@ struct erofs_inode { > spinlock_t lock; > /* all backing inodes */ > struct list_head backing_head; > + /* processing list */ > + struct list_head processing_head; > }; > > struct { > struct inode *ishare; > struct list_head backing_link; > + struct list_head processing_link; > + atomic_t processing_count; > }; > }; > #endif > diff --git a/fs/erofs/ishare.c b/fs/erofs/ishare.c > index 910b732bf8e7..73432b13bf75 100644 > --- a/fs/erofs/ishare.c > +++ b/fs/erofs/ishare.c > @@ -72,6 +72,7 @@ static int erofs_ishare_iget5_set(struct inode *inode, void *data) > > vi->fingerprint = data; > INIT_LIST_HEAD(&vi->backing_head); > + INIT_LIST_HEAD(&vi->processing_head); > spin_lock_init(&vi->lock); > return 0; > } > @@ -124,7 +125,9 @@ bool erofs_ishare_fill_inode(struct inode *inode) > } > > INIT_LIST_HEAD(&vi->backing_link); > + INIT_LIST_HEAD(&vi->processing_link); > vi->ishare = idedup; > + > spin_lock(&EROFS_I(idedup)->lock); > list_add(&vi->backing_link, &EROFS_I(idedup)->backing_head); > spin_unlock(&EROFS_I(idedup)->lock); > @@ -234,3 +237,83 @@ const struct file_operations erofs_ishare_fops = { > .get_unmapped_area = thp_get_unmapped_area, > .splice_read = filemap_splice_read, > }; > + > +void erofs_read_begin(struct erofs_read_ctx *rdctx) > +{ > + struct erofs_inode *vi, *vi_dedup; > + > + if (!rdctx->file || !erofs_is_ishare_inode(rdctx->inode)) > + return; > + > + vi = rdctx->file->private_data; > + vi_dedup = EROFS_I(file_inode(rdctx->file)); > + > + spin_lock(&vi_dedup->lock); > + if (!list_empty(&vi->processing_link)) { > + atomic_inc(&vi->processing_count); > + } else { > + list_add(&vi->processing_link, > + &vi_dedup->processing_head); > + atomic_set(&vi->processing_count, 1); > + } > + spin_unlock(&vi_dedup->lock); > +} > + > +void erofs_read_end(struct erofs_read_ctx *rdctx) > +{ > + struct erofs_inode *vi, *vi_dedup; > + > + if (!rdctx->file || !erofs_is_ishare_inode(rdctx->inode)) > + return; > + > + vi = rdctx->file->private_data; > + vi_dedup = EROFS_I(file_inode(rdctx->file)); > + > + spin_lock(&vi_dedup->lock); > + if (atomic_dec_and_test(&vi->processing_count)) > + list_del_init(&vi->processing_link); > + spin_unlock(&vi_dedup->lock); > +} > + > +/* > + * erofs_ishare_iget - find the backing inode. > + */ > +struct inode *erofs_ishare_iget(struct inode *inode) > +{ > + struct erofs_inode *vi, *vi_dedup; > + struct inode *realinode; > + > + if (!erofs_is_ishare_inode(inode)) > + return igrab(inode); > + > + vi_dedup = EROFS_I(inode); > + spin_lock(&vi_dedup->lock); > + /* try processing inodes first */ > + if (!list_empty(&vi_dedup->processing_head)) { > + list_for_each_entry(vi, &vi_dedup->processing_head, > + processing_link) { > + realinode = igrab(&vi->vfs_inode); > + if (realinode) { > + spin_unlock(&vi_dedup->lock); > + return realinode; > + } > + } > + } > + > + /* fall back to all backing inodes */ > + DBG_BUGON(list_empty(&vi_dedup->backing_head)); > + list_for_each_entry(vi, &vi_dedup->backing_head, backing_link) { > + realinode = igrab(&vi->vfs_inode); > + if (realinode) > + break; > + } > + spin_unlock(&vi_dedup->lock); > + > + DBG_BUGON(!realinode); > + return realinode; > +} > + > +void erofs_ishare_iput(struct inode *realinode) > +{ > + iput(realinode); > +} > diff --git a/fs/erofs/ishare.h b/fs/erofs/ishare.h > index 54f2251c8179..b85fa240507b 100644 > --- a/fs/erofs/ishare.h > +++ b/fs/erofs/ishare.h > @@ -9,6 +9,11 @@ > #include > #include "internal.h" > > +struct erofs_read_ctx { > + struct file *file; /* may be NULL */ > + struct inode *inode; > +}; > + > #ifdef CONFIG_EROFS_FS_INODE_SHARE > > int erofs_ishare_init(struct super_block *sb); > @@ -16,6 +21,13 @@ void erofs_ishare_exit(struct super_block *sb); > bool erofs_ishare_fill_inode(struct inode *inode); > void erofs_ishare_free_inode(struct inode *inode); > > +/* read/readahead */ > +void erofs_read_begin(struct erofs_read_ctx *rdctx); > +void erofs_read_end(struct erofs_read_ctx *rdctx); > + > +struct inode *erofs_ishare_iget(struct inode *inode); > +void erofs_ishare_iput(struct inode *realinode); > + > #else > > static inline int erofs_ishare_init(struct super_block *sb) { return 0; } > @@ -23,6 +35,12 @@ static inline void erofs_ishare_exit(struct super_block *sb) {} > static inline bool erofs_ishare_fill_inode(struct inode *inode) { return false; } > static inline void erofs_ishare_free_inode(struct inode *inode) {} > > +static inline void erofs_read_begin(struct erofs_read_ctx *rdctx) {} > +static inline void erofs_read_end(struct erofs_read_ctx *rdctx) {} > + > +static inline struct inode *erofs_ishare_iget(struct inode *inode) { return inode; } > +static inline void erofs_ishare_iput(struct inode *realinode) {} > + > #endif // CONFIG_EROFS_FS_INODE_SHARE > > #endif > diff --git a/fs/erofs/super.c b/fs/erofs/super.c > index f067633c0072..cba3da383558 100644 > --- a/fs/erofs/super.c > +++ b/fs/erofs/super.c > @@ -97,6 +97,7 @@ static void erofs_free_inode(struct inode *inode) > erofs_free_dedup_inode(vi); > return; > } > + erofs_ishare_free_inode(inode); > if (inode->i_op == &erofs_fast_symlink_iops) > kfree(inode->i_link); > kfree(vi->xattr_shared_xattrs); > @@ -762,6 +763,10 @@ static int erofs_fc_fill_super(struct super_block *sb, struct fs_context *fc) > if (err) > return err; > > + err = erofs_ishare_init(sb); > + if (err) > + return err; > + > sbi->dir_ra_bytes = EROFS_DIR_RA_BYTES; > erofs_info(sb, "mounted with root inode @ nid %llu.", sbi->root_nid); > return 0; > @@ -911,6 +916,7 @@ static void erofs_kill_sb(struct super_block *sb) > kill_anon_super(sb); > else > kill_block_super(sb); > + > erofs_drop_internal_inodes(sbi); > fs_put_dax(sbi->dif0.dax_dev, NULL); > erofs_fscache_unregister_fs(sb); > @@ -922,6 +928,7 @@ static void erofs_put_super(struct super_block *sb) > { > struct erofs_sb_info *const sbi = EROFS_SB(sb); > > + erofs_ishare_exit(sb); > erofs_unregister_sysfs(sb); > erofs_shrinker_unregister(sb); > erofs_xattr_prefixes_cleanup(sb);