From nobody Sat Feb 7 06:55:54 2026 Received: from canpmsgout01.his.huawei.com (canpmsgout01.his.huawei.com [113.46.200.216]) (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 CFA7631B111; Wed, 31 Dec 2025 09:14:12 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=113.46.200.216 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767172455; cv=none; b=fua37b49f2qTWpe6TnQrVFyS/RqoPyXXKHY4BJMQd2mb3M5AzV9hkM2GzSazOsUJzt5pak8Lqk3OKuO7S941fJed8IdDbP21fh/ghsgks3+4Muvppd8KxNPRQ+tjaYso1VJ6nIIGzPQ1wF2YUDD+qsyOt36tGM1RnykUlcBYP48= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767172455; c=relaxed/simple; bh=FDdlPmjWR956Laimcxh6D73LlWAcNyLae7aOSKhM9go=; h=From:To:CC:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=snOgjSI4/JV7i5cay+4fX2U5vtUbwRweJfesxLNZXa2/+k8G44RjeauvMLF94W8YXaS3mP1LsUzklMfHp/y/OZMje2rlALn2bH6pidkYleLZ15jYnkwvwAThb3CCWGmyP5Z3GyLmBdsHe0l06bTjEBbul6uHQx0YaEBgUO0lSF8= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com; spf=pass smtp.mailfrom=huawei.com; dkim=pass (1024-bit key) header.d=huawei.com header.i=@huawei.com header.b=YtLVKg9Q; arc=none smtp.client-ip=113.46.200.216 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huawei.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=huawei.com header.i=@huawei.com header.b="YtLVKg9Q" dkim-signature: v=1; a=rsa-sha256; d=huawei.com; s=dkim; c=relaxed/relaxed; q=dns/txt; h=From; bh=blCE/MmPqYfBuawXGsDKLTcGDcPKVdlLgTzlVCH0Olo=; b=YtLVKg9Q5uIyIYzsa3dZkLnOI6NofGHL8T43zgDBlYC8BXKDd01gO099H4/FvHdwjUmmsLE+z XhO1DAUrO9tQoNCfpPJFh7wqSecMCulnK7h/HeKetdiPq8FRb+97ag3O99rR6S+oAy3aBbmpatH 61tOpQjsPtVdscbTkYqGW6c= Received: from mail.maildlp.com (unknown [172.19.162.223]) by canpmsgout01.his.huawei.com (SkyGuard) with ESMTPS id 4dh42V1bPpz1T4FV; Wed, 31 Dec 2025 17:11:30 +0800 (CST) Received: from kwepemr500015.china.huawei.com (unknown [7.202.195.162]) by mail.maildlp.com (Postfix) with ESMTPS id 099FD4056E; Wed, 31 Dec 2025 17:14:02 +0800 (CST) Received: from huawei.com (10.67.174.162) by kwepemr500015.china.huawei.com (7.202.195.162) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.11; Wed, 31 Dec 2025 17:14:01 +0800 From: Hongbo Li To: , , CC: , , , , , , Subject: [PATCH v12 08/10] erofs: support unencoded inodes for page cache share Date: Wed, 31 Dec 2025 09:01:16 +0000 Message-ID: <20251231090118.541061-9-lihongbo22@huawei.com> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20251231090118.541061-1-lihongbo22@huawei.com> References: <20251231090118.541061-1-lihongbo22@huawei.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-ClientProxiedBy: kwepems500002.china.huawei.com (7.221.188.17) To kwepemr500015.china.huawei.com (7.202.195.162) Content-Type: text/plain; charset="utf-8" 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 Reviewed-by: Gao Xiang --- fs/erofs/data.c | 30 +++++++++++++++++++++++------- fs/erofs/inode.c | 4 ++++ fs/erofs/internal.h | 6 ++++++ fs/erofs/ishare.c | 32 ++++++++++++++++++++++++++++++++ 4 files changed, 65 insertions(+), 7 deletions(-) diff --git a/fs/erofs/data.c b/fs/erofs/data.c index 71e23d91123d..5fc8e3ce0d9e 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; }; =20 static int erofs_iomap_begin(struct inode *inode, loff_t offset, loff_t le= ngth, @@ -276,14 +277,15 @@ static int erofs_iomap_begin(struct inode *inode, lof= f_t offset, loff_t length, { struct iomap_iter *iter =3D container_of(iomap, struct iomap_iter, iomap); struct erofs_iomap_iter_ctx *ctx =3D iter->private; - struct super_block *sb =3D inode->i_sb; + struct inode *realinode =3D ctx ? ctx->realinode : inode; + struct super_block *sb =3D realinode->i_sb; struct erofs_map_blocks map; struct erofs_map_dev mdev; int ret; =20 map.m_la =3D offset; map.m_llen =3D length; - ret =3D erofs_map_blocks(inode, &map); + ret =3D erofs_map_blocks(realinode, &map); if (ret < 0) return ret; =20 @@ -296,7 +298,7 @@ static int erofs_iomap_begin(struct inode *inode, loff_= t offset, loff_t length, return 0; } =20 - 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 =3D (struct erofs_map_dev) { .m_deviceid =3D map.m_deviceid, .m_pa =3D map.m_pa, @@ -322,7 +324,7 @@ static int erofs_iomap_begin(struct inode *inode, loff_= t offset, loff_t length, void *ptr; =20 ptr =3D 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 =3D ptr; @@ -379,30 +381,42 @@ int erofs_fiemap(struct inode *inode, struct fiemap_e= xtent_info *fieinfo, */ static int erofs_read_folio(struct file *file, struct folio *folio) { + struct inode *inode =3D folio_inode(folio); struct iomap_read_folio_ctx read_ctx =3D { .ops =3D &iomap_bio_read_ops, .cur_folio =3D folio, }; - struct erofs_iomap_iter_ctx iter_ctx =3D {}; + bool need_iput; + struct erofs_iomap_iter_ctx iter_ctx =3D { + .realinode =3D erofs_real_inode(inode, &need_iput), + }; =20 trace_erofs_read_folio(folio, true); =20 iomap_read_folio(&erofs_iomap_ops, &read_ctx, &iter_ctx); + if (need_iput) + iput(iter_ctx.realinode); return 0; } =20 static void erofs_readahead(struct readahead_control *rac) { + struct inode *inode =3D rac->mapping->host; struct iomap_read_folio_ctx read_ctx =3D { .ops =3D &iomap_bio_read_ops, .rac =3D rac, }; - struct erofs_iomap_iter_ctx iter_ctx =3D {}; + bool need_iput; + struct erofs_iomap_iter_ctx iter_ctx =3D { + .realinode =3D erofs_real_inode(inode, &need_iput), + }; =20 trace_erofs_readahead(rac->mapping->host, readahead_index(rac), readahead_count(rac), true); =20 iomap_readahead(&erofs_iomap_ops, &read_ctx, &iter_ctx); + if (need_iput) + iput(iter_ctx.realinode); } =20 static sector_t erofs_bmap(struct address_space *mapping, sector_t block) @@ -423,7 +437,9 @@ 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 =3D {}; + struct erofs_iomap_iter_ctx iter_ctx =3D { + .realinode =3D inode, + }; =20 return iomap_dio_rw(iocb, to, &erofs_iomap_ops, NULL, 0, &iter_ctx, 0); diff --git a/fs/erofs/inode.c b/fs/erofs/inode.c index bce98c845a18..8116738fe432 100644 --- a/fs/erofs/inode.c +++ b/fs/erofs/inode.c @@ -215,6 +215,10 @@ static int erofs_fill_inode(struct inode *inode) case S_IFREG: inode->i_op =3D &erofs_generic_iops; inode->i_fop =3D &erofs_file_fops; +#ifdef CONFIG_EROFS_FS_PAGE_CACHE_SHARE + if (erofs_ishare_fill_inode(inode)) + inode->i_fop =3D &erofs_ishare_fops; +#endif break; case S_IFDIR: inode->i_op =3D &erofs_dir_iops; diff --git a/fs/erofs/internal.h b/fs/erofs/internal.h index 6ef1cdd9d651..b02defbcdbfe 100644 --- a/fs/erofs/internal.h +++ b/fs/erofs/internal.h @@ -565,11 +565,17 @@ int __init erofs_init_ishare(void); void erofs_exit_ishare(void); bool erofs_ishare_fill_inode(struct inode *inode); void erofs_ishare_free_inode(struct inode *inode); +struct inode *erofs_real_inode(struct inode *inode, bool *need_iput); #else static inline int erofs_init_ishare(void) { return 0; } static inline void erofs_exit_ishare(void) {} static inline bool erofs_ishare_fill_inode(struct inode *inode) { return f= alse; } static inline void erofs_ishare_free_inode(struct inode *inode) {} +static inline struct inode *erofs_real_inode(struct inode *inode, bool *ne= ed_iput) +{ + *need_iput =3D false; + return inode; +} #endif // CONFIG_EROFS_FS_PAGE_CACHE_SHARE =20 long erofs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg); diff --git a/fs/erofs/ishare.c b/fs/erofs/ishare.c index e93d379d4a3a..b91f0ce412c0 100644 --- a/fs/erofs/ishare.c +++ b/fs/erofs/ishare.c @@ -11,6 +11,12 @@ =20 static struct vfsmount *erofs_ishare_mnt; =20 +static inline bool erofs_is_ishare_inode(struct inode *inode) +{ + /* assumed FS_ONDEMAND is excluded with FS_PAGE_CACHE_SHARE feature */ + return inode->i_sb->s_type =3D=3D &erofs_anon_fs_type; +} + static int erofs_ishare_iget5_eq(struct inode *inode, void *data) { struct erofs_inode_fingerprint *fp1 =3D &EROFS_I(inode)->fingerprint; @@ -156,6 +162,32 @@ const struct file_operations erofs_ishare_fops =3D { .splice_read =3D filemap_splice_read, }; =20 +struct inode *erofs_real_inode(struct inode *inode, bool *need_iput) +{ + struct erofs_inode *vi, *vi_share; + struct inode *realinode; + + *need_iput =3D false; + if (!erofs_is_ishare_inode(inode)) + return inode; + + vi_share =3D EROFS_I(inode); + spin_lock(&vi_share->ishare_lock); + /* fetch any one as real inode */ + DBG_BUGON(list_empty(&vi_share->ishare_list)); + list_for_each_entry(vi, &vi_share->ishare_list, ishare_list) { + realinode =3D igrab(&vi->vfs_inode); + if (realinode) { + *need_iput =3D true; + break; + } + } + spin_unlock(&vi_share->ishare_lock); + + DBG_BUGON(!realinode); + return realinode; +} + int __init erofs_init_ishare(void) { erofs_ishare_mnt =3D kern_mount(&erofs_anon_fs_type); --=20 2.22.0