diff options
-rw-r--r-- | fs/btrfs/free-space-cache.c | 63 | ||||
-rw-r--r-- | fs/btrfs/free-space-cache.h | 17 | ||||
-rw-r--r-- | fs/btrfs/inode-map.c | 13 |
3 files changed, 79 insertions, 14 deletions
diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c index 3283da419200..669809d5214e 100644 --- a/fs/btrfs/free-space-cache.c +++ b/fs/btrfs/free-space-cache.c @@ -752,6 +752,14 @@ static int __load_free_space_cache(struct btrfs_root *root, struct inode *inode, goto free_cache; } + /* + * Sync discard ensures that the free space cache is always + * trimmed. So when reading this in, the state should reflect + * that. + */ + if (btrfs_test_opt(fs_info, DISCARD_SYNC)) + e->trim_state = BTRFS_TRIM_STATE_TRIMMED; + if (!e->bytes) { kmem_cache_free(btrfs_free_space_cachep, e); goto free_cache; @@ -2161,6 +2169,22 @@ out: return ret; } +/* + * Free space merging rules: + * 1) Merge trimmed areas together + * 2) Let untrimmed areas coalesce with trimmed areas + * 3) Always pull neighboring regions from bitmaps + * + * The above rules are for when we merge free space based on btrfs_trim_state. + * Rules 2 and 3 are subtle because they are suboptimal, but are done for the + * same reason: to promote larger extent regions which makes life easier for + * find_free_extent(). Rule 2 enables coalescing based on the common path + * being returning free space from btrfs_finish_extent_commit(). So when free + * space is trimmed, it will prevent aggregating trimmed new region and + * untrimmed regions in the rb_tree. Rule 3 is purely to obtain larger extents + * and provide find_free_extent() with the largest extents possible hoping for + * the reuse path. + */ static bool try_merge_free_space(struct btrfs_free_space_ctl *ctl, struct btrfs_free_space *info, bool update_stat) { @@ -2169,6 +2193,7 @@ static bool try_merge_free_space(struct btrfs_free_space_ctl *ctl, bool merged = false; u64 offset = info->offset; u64 bytes = info->bytes; + const bool is_trimmed = btrfs_free_space_trimmed(info); /* * first we want to see if there is free space adjacent to the range we @@ -2182,7 +2207,9 @@ static bool try_merge_free_space(struct btrfs_free_space_ctl *ctl, else left_info = tree_search_offset(ctl, offset - 1, 0, 0); - if (right_info && !right_info->bitmap) { + /* See try_merge_free_space() comment. */ + if (right_info && !right_info->bitmap && + (!is_trimmed || btrfs_free_space_trimmed(right_info))) { if (update_stat) unlink_free_space(ctl, right_info); else @@ -2192,8 +2219,10 @@ static bool try_merge_free_space(struct btrfs_free_space_ctl *ctl, merged = true; } + /* See try_merge_free_space() comment. */ if (left_info && !left_info->bitmap && - left_info->offset + left_info->bytes == offset) { + left_info->offset + left_info->bytes == offset && + (!is_trimmed || btrfs_free_space_trimmed(left_info))) { if (update_stat) unlink_free_space(ctl, left_info); else @@ -2229,6 +2258,10 @@ static bool steal_from_bitmap_to_end(struct btrfs_free_space_ctl *ctl, bytes = (j - i) * ctl->unit; info->bytes += bytes; + /* See try_merge_free_space() comment. */ + if (!btrfs_free_space_trimmed(bitmap)) + info->trim_state = BTRFS_TRIM_STATE_UNTRIMMED; + if (update_stat) bitmap_clear_bits(ctl, bitmap, end, bytes); else @@ -2282,6 +2315,10 @@ static bool steal_from_bitmap_to_front(struct btrfs_free_space_ctl *ctl, info->offset -= bytes; info->bytes += bytes; + /* See try_merge_free_space() comment. */ + if (!btrfs_free_space_trimmed(bitmap)) + info->trim_state = BTRFS_TRIM_STATE_UNTRIMMED; + if (update_stat) bitmap_clear_bits(ctl, bitmap, info->offset, bytes); else @@ -2331,7 +2368,8 @@ static void steal_from_bitmap(struct btrfs_free_space_ctl *ctl, int __btrfs_add_free_space(struct btrfs_fs_info *fs_info, struct btrfs_free_space_ctl *ctl, - u64 offset, u64 bytes) + u64 offset, u64 bytes, + enum btrfs_trim_state trim_state) { struct btrfs_free_space *info; int ret = 0; @@ -2342,6 +2380,7 @@ int __btrfs_add_free_space(struct btrfs_fs_info *fs_info, info->offset = offset; info->bytes = bytes; + info->trim_state = trim_state; RB_CLEAR_NODE(&info->offset_index); spin_lock(&ctl->tree_lock); @@ -2387,9 +2426,14 @@ out: int btrfs_add_free_space(struct btrfs_block_group *block_group, u64 bytenr, u64 size) { + enum btrfs_trim_state trim_state = BTRFS_TRIM_STATE_UNTRIMMED; + + if (btrfs_test_opt(block_group->fs_info, DISCARD_SYNC)) + trim_state = BTRFS_TRIM_STATE_TRIMMED; + return __btrfs_add_free_space(block_group->fs_info, block_group->free_space_ctl, - bytenr, size); + bytenr, size, trim_state); } int btrfs_remove_free_space(struct btrfs_block_group *block_group, @@ -2464,8 +2508,10 @@ again: } spin_unlock(&ctl->tree_lock); - ret = btrfs_add_free_space(block_group, offset + bytes, - old_end - (offset + bytes)); + ret = __btrfs_add_free_space(block_group->fs_info, ctl, + offset + bytes, + old_end - (offset + bytes), + info->trim_state); WARN_ON(ret); goto out; } @@ -2634,6 +2680,7 @@ u64 btrfs_find_space_for_alloc(struct btrfs_block_group *block_group, u64 ret = 0; u64 align_gap = 0; u64 align_gap_len = 0; + enum btrfs_trim_state align_gap_trim_state = BTRFS_TRIM_STATE_UNTRIMMED; spin_lock(&ctl->tree_lock); entry = find_free_space(ctl, &offset, &bytes_search, @@ -2650,6 +2697,7 @@ u64 btrfs_find_space_for_alloc(struct btrfs_block_group *block_group, unlink_free_space(ctl, entry); align_gap_len = offset - entry->offset; align_gap = entry->offset; + align_gap_trim_state = entry->trim_state; entry->offset = offset + bytes; WARN_ON(entry->bytes < bytes + align_gap_len); @@ -2665,7 +2713,8 @@ out: if (align_gap_len) __btrfs_add_free_space(block_group->fs_info, ctl, - align_gap, align_gap_len); + align_gap, align_gap_len, + align_gap_trim_state); return ret; } diff --git a/fs/btrfs/free-space-cache.h b/fs/btrfs/free-space-cache.h index ba9a23241101..66c073f854dc 100644 --- a/fs/btrfs/free-space-cache.h +++ b/fs/btrfs/free-space-cache.h @@ -6,6 +6,14 @@ #ifndef BTRFS_FREE_SPACE_CACHE_H #define BTRFS_FREE_SPACE_CACHE_H +/* + * This is the trim state of an extent or bitmap. + */ +enum btrfs_trim_state { + BTRFS_TRIM_STATE_UNTRIMMED, + BTRFS_TRIM_STATE_TRIMMED, +}; + struct btrfs_free_space { struct rb_node offset_index; u64 offset; @@ -13,8 +21,14 @@ struct btrfs_free_space { u64 max_extent_size; unsigned long *bitmap; struct list_head list; + enum btrfs_trim_state trim_state; }; +static inline bool btrfs_free_space_trimmed(struct btrfs_free_space *info) +{ + return (info->trim_state == BTRFS_TRIM_STATE_TRIMMED); +} + struct btrfs_free_space_ctl { spinlock_t tree_lock; struct rb_root free_space_offset; @@ -83,7 +97,8 @@ int btrfs_write_out_ino_cache(struct btrfs_root *root, void btrfs_init_free_space_ctl(struct btrfs_block_group *block_group); int __btrfs_add_free_space(struct btrfs_fs_info *fs_info, struct btrfs_free_space_ctl *ctl, - u64 bytenr, u64 size); + u64 bytenr, u64 size, + enum btrfs_trim_state trim_state); int btrfs_add_free_space(struct btrfs_block_group *block_group, u64 bytenr, u64 size); int btrfs_remove_free_space(struct btrfs_block_group *block_group, diff --git a/fs/btrfs/inode-map.c b/fs/btrfs/inode-map.c index 37345fb6191d..d5c9c69d8263 100644 --- a/fs/btrfs/inode-map.c +++ b/fs/btrfs/inode-map.c @@ -107,7 +107,7 @@ again: if (last != (u64)-1 && last + 1 != key.objectid) { __btrfs_add_free_space(fs_info, ctl, last + 1, - key.objectid - last - 1); + key.objectid - last - 1, 0); wake_up(&root->ino_cache_wait); } @@ -118,7 +118,7 @@ next: if (last < root->highest_objectid - 1) { __btrfs_add_free_space(fs_info, ctl, last + 1, - root->highest_objectid - last - 1); + root->highest_objectid - last - 1, 0); } spin_lock(&root->ino_cache_lock); @@ -175,7 +175,8 @@ static void start_caching(struct btrfs_root *root) ret = btrfs_find_free_objectid(root, &objectid); if (!ret && objectid <= BTRFS_LAST_FREE_OBJECTID) { __btrfs_add_free_space(fs_info, ctl, objectid, - BTRFS_LAST_FREE_OBJECTID - objectid + 1); + BTRFS_LAST_FREE_OBJECTID - objectid + 1, + 0); wake_up(&root->ino_cache_wait); } @@ -221,7 +222,7 @@ void btrfs_return_ino(struct btrfs_root *root, u64 objectid) return; again: if (root->ino_cache_state == BTRFS_CACHE_FINISHED) { - __btrfs_add_free_space(fs_info, pinned, objectid, 1); + __btrfs_add_free_space(fs_info, pinned, objectid, 1, 0); } else { down_write(&fs_info->commit_root_sem); spin_lock(&root->ino_cache_lock); @@ -234,7 +235,7 @@ again: start_caching(root); - __btrfs_add_free_space(fs_info, pinned, objectid, 1); + __btrfs_add_free_space(fs_info, pinned, objectid, 1, 0); up_write(&fs_info->commit_root_sem); } @@ -281,7 +282,7 @@ void btrfs_unpin_free_ino(struct btrfs_root *root) spin_unlock(rbroot_lock); if (count) __btrfs_add_free_space(root->fs_info, ctl, - info->offset, count); + info->offset, count, 0); kmem_cache_free(btrfs_free_space_cachep, info); } } |