From 701a813fe5c271bd8ac5a90c3541ee0fbdc95fcd Mon Sep 17 00:00:00 2001 From: Filipe Manana Date: Mon, 18 Aug 2025 22:40:16 -0400 Subject: [PATCH 1/2] btrfs: send: add and use helper to rename current inode when processing refs ANBZ: #27255 [ Upstream commit ec666c84deba56f714505b53556a97565f72db86 ] Extract the logic to rename the current inode at process_recorded_refs() into a helper function and use it, therefore removing duplicated logic and making it easier for an upcoming patch by avoiding yet more duplicated logic. Signed-off-by: Filipe Manana Reviewed-by: David Sterba Signed-off-by: David Sterba Stable-dep-of: 005b0a0c24e1 ("btrfs: send: use fallocate for hole punching with send stream v2") Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman Signed-off-by: Chu Guangqing --- fs/btrfs/send.c | 23 +++++++++++++++-------- 1 file changed, 15 insertions(+), 8 deletions(-) diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c index e2ead36e5be4..6cfc77f6d972 100644 --- a/fs/btrfs/send.c +++ b/fs/btrfs/send.c @@ -4166,6 +4166,19 @@ static int refresh_ref_path(struct send_ctx *sctx, struct recorded_ref *ref) return ret; } +static int rename_current_inode(struct send_ctx *sctx, + struct fs_path *current_path, + struct fs_path *new_path) +{ + int ret; + + ret = send_rename(sctx, current_path, new_path); + if (ret < 0) + return ret; + + return fs_path_copy(current_path, new_path); +} + /* * This does all the move/link/unlink/rmdir magic. */ @@ -4451,13 +4464,10 @@ static int process_recorded_refs(struct send_ctx *sctx, int *pending_move) * it depending on the inode mode. */ if (is_orphan && can_rename) { - ret = send_rename(sctx, valid_path, cur->full_path); + ret = rename_current_inode(sctx, valid_path, cur->full_path); if (ret < 0) goto out; is_orphan = 0; - ret = fs_path_copy(valid_path, cur->full_path); - if (ret < 0) - goto out; } else if (can_rename) { if (S_ISDIR(sctx->cur_inode_mode)) { /* @@ -4465,10 +4475,7 @@ static int process_recorded_refs(struct send_ctx *sctx, int *pending_move) * dirs, we always have one new and one deleted * ref. The deleted ref is ignored later. */ - ret = send_rename(sctx, valid_path, - cur->full_path); - if (!ret) - ret = fs_path_copy(valid_path, + ret = rename_current_inode(sctx, valid_path, cur->full_path); if (ret < 0) goto out; -- Gitee From 3ab61d8f7b3b81d0e9ff30d106c5f2120f896ab5 Mon Sep 17 00:00:00 2001 From: Filipe Manana Date: Mon, 18 Aug 2025 22:40:17 -0400 Subject: [PATCH 2/2] btrfs: send: keep the current inode's path cached ANBZ: #27255 [ Upstream commit fc746acb7aa9aeaa2cb5dcba449323319ba5c8eb ] Whenever we need to send a command for the current inode, like sending writes, xattr updates, truncates, utimes, etc, we compute the inode's path each time, which implies doing some memory allocations and traversing the inode hierarchy to extract the name of the inode and each ancestor directory, and that implies doing lookups in the subvolume tree amongst other operations. Most of the time, by far, the current inode's path doesn't change while we are processing it (like if we need to issue 100 write commands, the path remains the same and it's pointless to compute it 100 times). To avoid this keep the current inode's path cached in the send context and invalidate it or update it whenever it's needed (after unlinks or renames). A performance test, and its results, is mentioned in the next patch in the series (subject: "btrfs: send: avoid path allocation for the current inode when issuing commands"). Signed-off-by: Filipe Manana Reviewed-by: David Sterba Signed-off-by: David Sterba Stable-dep-of: 005b0a0c24e1 ("btrfs: send: use fallocate for hole punching with send stream v2") Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman Signed-off-by: Chu Guangqing --- fs/btrfs/send.c | 53 ++++++++++++++++++++++++++++++++++++++++++++----- 1 file changed, 48 insertions(+), 5 deletions(-) diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c index 6cfc77f6d972..11cd5ebde2b2 100644 --- a/fs/btrfs/send.c +++ b/fs/btrfs/send.c @@ -179,6 +179,7 @@ struct send_ctx { u64 cur_inode_rdev; u64 cur_inode_last_extent; u64 cur_inode_next_write_offset; + struct fs_path cur_inode_path; bool cur_inode_new; bool cur_inode_new_gen; bool cur_inode_deleted; @@ -436,6 +437,14 @@ static void fs_path_reset(struct fs_path *p) } } +static void init_path(struct fs_path *p) +{ + p->reversed = 0; + p->buf = p->inline_buf; + p->buf_len = FS_PATH_INLINE_SIZE; + fs_path_reset(p); +} + static struct fs_path *fs_path_alloc(void) { struct fs_path *p; @@ -443,10 +452,7 @@ static struct fs_path *fs_path_alloc(void) p = kmalloc(sizeof(*p), GFP_KERNEL); if (!p) return NULL; - p->reversed = 0; - p->buf = p->inline_buf; - p->buf_len = FS_PATH_INLINE_SIZE; - fs_path_reset(p); + init_path(p); return p; } @@ -624,6 +630,14 @@ static void fs_path_unreverse(struct fs_path *p) p->reversed = 0; } +static inline bool is_current_inode_path(const struct send_ctx *sctx, + const struct fs_path *path) +{ + const struct fs_path *cur = &sctx->cur_inode_path; + + return (strncmp(path->start, cur->start, fs_path_len(cur)) == 0); +} + static struct btrfs_path *alloc_path_for_send(void) { struct btrfs_path *path; @@ -2450,6 +2464,14 @@ static int get_cur_path(struct send_ctx *sctx, u64 ino, u64 gen, u64 parent_inode = 0; u64 parent_gen = 0; int stop = 0; + const bool is_cur_inode = (ino == sctx->cur_ino && gen == sctx->cur_inode_gen); + + if (is_cur_inode && fs_path_len(&sctx->cur_inode_path) > 0) { + if (dest != &sctx->cur_inode_path) + return fs_path_copy(dest, &sctx->cur_inode_path); + + return 0; + } name = fs_path_alloc(); if (!name) { @@ -2501,8 +2523,12 @@ static int get_cur_path(struct send_ctx *sctx, u64 ino, u64 gen, out: fs_path_free(name); - if (!ret) + if (!ret) { fs_path_unreverse(dest); + if (is_cur_inode && dest != &sctx->cur_inode_path) + ret = fs_path_copy(&sctx->cur_inode_path, dest); + } + return ret; } @@ -3113,6 +3139,11 @@ static int orphanize_inode(struct send_ctx *sctx, u64 ino, u64 gen, goto out; ret = send_rename(sctx, path, orphan); + if (ret < 0) + goto out; + + if (ino == sctx->cur_ino && gen == sctx->cur_inode_gen) + ret = fs_path_copy(&sctx->cur_inode_path, orphan); out: fs_path_free(orphan); @@ -4176,6 +4207,10 @@ static int rename_current_inode(struct send_ctx *sctx, if (ret < 0) return ret; + ret = fs_path_copy(&sctx->cur_inode_path, new_path); + if (ret < 0) + return ret; + return fs_path_copy(current_path, new_path); } @@ -4369,6 +4404,7 @@ static int process_recorded_refs(struct send_ctx *sctx, int *pending_move) if (ret > 0) { orphanized_ancestor = true; fs_path_reset(valid_path); + fs_path_reset(&sctx->cur_inode_path); ret = get_cur_path(sctx, sctx->cur_ino, sctx->cur_inode_gen, valid_path); @@ -4568,6 +4604,8 @@ static int process_recorded_refs(struct send_ctx *sctx, int *pending_move) ret = send_unlink(sctx, cur->full_path); if (ret < 0) goto out; + if (is_current_inode_path(sctx, cur->full_path)) + fs_path_reset(&sctx->cur_inode_path); } ret = dup_ref(cur, &check_dirs); if (ret < 0) @@ -6911,6 +6949,7 @@ static int changed_inode(struct send_ctx *sctx, sctx->cur_inode_last_extent = (u64)-1; sctx->cur_inode_next_write_offset = 0; sctx->ignore_cur_inode = false; + fs_path_reset(&sctx->cur_inode_path); /* * Set send_progress to current inode. This will tell all get_cur_xxx @@ -8201,6 +8240,7 @@ long btrfs_ioctl_send(struct inode *inode, struct btrfs_ioctl_send_args *arg) goto out; } + init_path(&sctx->cur_inode_path); INIT_LIST_HEAD(&sctx->new_refs); INIT_LIST_HEAD(&sctx->deleted_refs); @@ -8486,6 +8526,9 @@ long btrfs_ioctl_send(struct inode *inode, struct btrfs_ioctl_send_args *arg) btrfs_lru_cache_clear(&sctx->dir_created_cache); btrfs_lru_cache_clear(&sctx->dir_utimes_cache); + if (sctx->cur_inode_path.buf != sctx->cur_inode_path.inline_buf) + kfree(sctx->cur_inode_path.buf); + kfree(sctx); } -- Gitee