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 <[email protected]> Signed-off-by: Hongzhen Luo <[email protected]> Signed-off-by: Hongbo Li <[email protected]> --- fs/erofs/data.c | 32 +++++++++++++++++++++++--------- fs/erofs/fileio.c | 25 ++++++++++++++++--------- fs/erofs/inode.c | 3 ++- fs/erofs/internal.h | 6 ++++++ fs/erofs/ishare.c | 34 ++++++++++++++++++++++++++++++++++ 5 files changed, 81 insertions(+), 19 deletions(-) diff --git a/fs/erofs/data.c b/fs/erofs/data.c index ea198defb531..3a4eb0dececd 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; @@ -383,10 +385,15 @@ 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_inode(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; } @@ -396,11 +403,16 @@ 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); 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) @@ -421,7 +433,9 @@ 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 d07dc248d264..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_inode(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 202cbbb4eada..d33816cff813 100644 --- a/fs/erofs/inode.c +++ b/fs/erofs/inode.c @@ -213,7 +213,8 @@ static int erofs_fill_inode(struct inode *inode) switch (inode->i_mode & S_IFMT) { case S_IFREG: inode->i_op = &erofs_generic_iops; - inode->i_fop = &erofs_file_fops; + inode->i_fop = erofs_ishare_fill_inode(inode) ? + &erofs_ishare_fops : &erofs_file_fops; break; case S_IFDIR: inode->i_op = &erofs_dir_iops; diff --git a/fs/erofs/internal.h b/fs/erofs/internal.h index 15945e3308b8..d38e63e361c1 100644 --- a/fs/erofs/internal.h +++ b/fs/erofs/internal.h @@ -591,11 +591,17 @@ 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 false; } static inline void erofs_ishare_free_inode(struct inode *inode) {} +static inline struct inode *erofs_real_inode(struct inode *inode, bool *need_iput) +{ + *need_iput = false; + return inode; +} #endif 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 6b710c935afb..affa34ac5b2e 100644 --- a/fs/erofs/ishare.c +++ b/fs/erofs/ishare.c @@ -11,6 +11,12 @@ static struct vfsmount *erofs_ishare_mnt; +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 == &erofs_anon_fs_type; +} + static int erofs_ishare_iget5_eq(struct inode *inode, void *data) { struct erofs_inode_fingerprint *fp1 = &EROFS_I(inode)->fingerprint; @@ -38,6 +44,8 @@ bool erofs_ishare_fill_inode(struct inode *inode) struct inode *sharedinode; unsigned long hash; + if (erofs_inode_is_data_compressed(vi->datalayout)) + return false; if (erofs_xattr_fill_inode_fingerprint(&fp, inode, sbi->domain_id)) return false; hash = xxh32(fp.opaque, fp.size, 0); @@ -149,6 +157,32 @@ const struct file_operations erofs_ishare_fops = { .splice_read = filemap_splice_read, }; +struct inode *erofs_real_inode(struct inode *inode, bool *need_iput) +{ + struct erofs_inode *vi, *vi_share; + struct inode *realinode; + + *need_iput = false; + if (!erofs_is_ishare_inode(inode)) + return inode; + + vi_share = 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 = igrab(&vi->vfs_inode); + if (realinode) { + *need_iput = true; + break; + } + } + spin_unlock(&vi_share->ishare_lock); + + DBG_BUGON(!realinode); + return realinode; +} + int __init erofs_init_ishare(void) { erofs_ishare_mnt = kern_mount(&erofs_anon_fs_type); -- 2.22.0
