diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index 49bc792108b9..16384231db82 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -2145,6 +2145,8 @@ struct btrfs_ioctl_defrag_range_args { #define BTRFS_MOUNT_CHECK_INTEGRITY_INCLUDING_EXTENT_DATA (1 << 21) #define BTRFS_MOUNT_PANIC_ON_FATAL_ERROR (1 << 22) #define BTRFS_MOUNT_RESCAN_UUID_TREE (1 << 23) +#define BTRFS_MOUNT_FRAGMENT_DATA (1 << 24) +#define BTRFS_MOUNT_FRAGMENT_METADATA (1 << 25) #define BTRFS_DEFAULT_COMMIT_INTERVAL (30) #define BTRFS_DEFAULT_MAX_INLINE (8192) @@ -2169,6 +2171,18 @@ struct btrfs_ioctl_defrag_range_args { btrfs_clear_opt(root->fs_info->mount_opt, opt); \ } +#ifdef CONFIG_BTRFS_DEBUG +static inline int +btrfs_should_fragment_free_space(struct btrfs_root *root, + struct btrfs_block_group_cache *block_group) +{ + return (btrfs_test_opt(root, FRAGMENT_METADATA) && + block_group->flags & BTRFS_BLOCK_GROUP_METADATA) || + (btrfs_test_opt(root, FRAGMENT_DATA) && + block_group->flags & BTRFS_BLOCK_GROUP_DATA); +} +#endif + /* * Requests for changes that need to be done during transaction commit. * diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index 2df4bc77f5b4..0e32abf53b5b 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -332,6 +332,27 @@ static void put_caching_control(struct btrfs_caching_control *ctl) kfree(ctl); } +#ifdef CONFIG_BTRFS_DEBUG +static void fragment_free_space(struct btrfs_root *root, + struct btrfs_block_group_cache *block_group) +{ + u64 start = block_group->key.objectid; + u64 len = block_group->key.offset; + u64 chunk = block_group->flags & BTRFS_BLOCK_GROUP_METADATA ? + root->nodesize : root->sectorsize; + u64 step = chunk << 1; + + while (len > chunk) { + btrfs_remove_free_space(block_group, start, chunk); + start += step; + if (len < step) + len = 0; + else + len -= step; + } +} +#endif + /* * this is only called by cache_block_group, since we could have freed extents * we need to check the pinned_extents for any extents that can't be used yet @@ -388,6 +409,7 @@ static noinline void caching_thread(struct btrfs_work *work) u64 last = 0; u32 nritems; int ret = -ENOMEM; + bool wakeup = true; caching_ctl = container_of(work, struct btrfs_caching_control, work); block_group = caching_ctl->block_group; @@ -400,6 +422,15 @@ static noinline void caching_thread(struct btrfs_work *work) last = max_t(u64, block_group->key.objectid, BTRFS_SUPER_INFO_OFFSET); +#ifdef CONFIG_BTRFS_DEBUG + /* + * If we're fragmenting we don't want to make anybody think we can + * allocate from this block group until we've had a chance to fragment + * the free space. + */ + if (btrfs_should_fragment_free_space(extent_root, block_group)) + wakeup = false; +#endif /* * We don't want to deadlock with somebody trying to allocate a new * extent for the extent root while also trying to search the extent @@ -441,7 +472,8 @@ next: if (need_resched() || rwsem_is_contended(&fs_info->commit_root_sem)) { - caching_ctl->progress = last; + if (wakeup) + caching_ctl->progress = last; btrfs_release_path(path); up_read(&fs_info->commit_root_sem); mutex_unlock(&caching_ctl->mutex); @@ -464,7 +496,8 @@ next: key.offset = 0; key.type = BTRFS_EXTENT_ITEM_KEY; - caching_ctl->progress = last; + if (wakeup) + caching_ctl->progress = last; btrfs_release_path(path); goto next; } @@ -491,7 +524,8 @@ next: if (total_found > (1024 * 1024 * 2)) { total_found = 0; - wake_up(&caching_ctl->wait); + if (wakeup) + wake_up(&caching_ctl->wait); } } path->slots[0]++; @@ -501,13 +535,27 @@ next: total_found += add_new_free_space(block_group, fs_info, last, block_group->key.objectid + block_group->key.offset); - caching_ctl->progress = (u64)-1; - spin_lock(&block_group->lock); block_group->caching_ctl = NULL; block_group->cached = BTRFS_CACHE_FINISHED; spin_unlock(&block_group->lock); +#ifdef CONFIG_BTRFS_DEBUG + if (btrfs_should_fragment_free_space(extent_root, block_group)) { + u64 bytes_used; + + spin_lock(&block_group->space_info->lock); + spin_lock(&block_group->lock); + bytes_used = block_group->key.offset - + btrfs_block_group_used(&block_group->item); + block_group->space_info->bytes_used += bytes_used >> 1; + spin_unlock(&block_group->lock); + spin_unlock(&block_group->space_info->lock); + fragment_free_space(extent_root, block_group); + } +#endif + + caching_ctl->progress = (u64)-1; err: btrfs_free_path(path); up_read(&fs_info->commit_root_sem); @@ -607,6 +655,22 @@ static int cache_block_group(struct btrfs_block_group_cache *cache, } } spin_unlock(&cache->lock); +#ifdef CONFIG_BTRFS_DEBUG + if (ret == 1 && + btrfs_should_fragment_free_space(fs_info->extent_root, + cache)) { + u64 bytes_used; + + spin_lock(&cache->space_info->lock); + spin_lock(&cache->lock); + bytes_used = cache->key.offset - + btrfs_block_group_used(&cache->item); + cache->space_info->bytes_used += bytes_used >> 1; + spin_unlock(&cache->lock); + spin_unlock(&cache->space_info->lock); + fragment_free_space(fs_info->extent_root, cache); + } +#endif mutex_unlock(&caching_ctl->mutex); wake_up(&caching_ctl->wait); @@ -9624,6 +9688,14 @@ int btrfs_make_block_group(struct btrfs_trans_handle *trans, free_excluded_extents(root, cache); +#ifdef CONFIG_BTRFS_DEBUG + if (btrfs_should_fragment_free_space(root, cache)) { + u64 new_bytes_used = size - bytes_used; + + bytes_used += new_bytes_used >> 1; + fragment_free_space(root, cache); + } +#endif /* * Call to ensure the corresponding space_info object is created and * assigned to our block group, but don't update its counters just yet. diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c index 5a9431dda07f..c0eb84ecb78f 100644 --- a/fs/btrfs/free-space-cache.c +++ b/fs/btrfs/free-space-cache.c @@ -1951,12 +1951,19 @@ static bool use_bitmap(struct btrfs_free_space_ctl *ctl, struct btrfs_free_space *info) { struct btrfs_block_group_cache *block_group = ctl->private; + bool forced = false; + +#ifdef CONFIG_BTRFS_DEBUG + if (btrfs_should_fragment_free_space(block_group->fs_info->extent_root, + block_group)) + forced = true; +#endif /* * If we are below the extents threshold then we can add this as an * extent, and don't have to deal with the bitmap */ - if (ctl->free_extents < ctl->extents_thresh) { + if (!forced && ctl->free_extents < ctl->extents_thresh) { /* * If this block group has some small extents we don't want to * use up all of our free slots in the cache with them, we want diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c index b23d49daa1a2..24154e422945 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -303,6 +303,9 @@ enum { Opt_commit_interval, Opt_barrier, Opt_nodefrag, Opt_nodiscard, Opt_noenospc_debug, Opt_noflushoncommit, Opt_acl, Opt_datacow, Opt_datasum, Opt_treelog, Opt_noinode_cache, +#ifdef CONFIG_BTRFS_DEBUG + Opt_fragment_data, Opt_fragment_metadata, Opt_fragment_all, +#endif Opt_err, }; @@ -355,6 +358,11 @@ static match_table_t tokens = { {Opt_rescan_uuid_tree, "rescan_uuid_tree"}, {Opt_fatal_errors, "fatal_errors=%s"}, {Opt_commit_interval, "commit=%d"}, +#ifdef CONFIG_BTRFS_DEBUG + {Opt_fragment_data, "fragment=data"}, + {Opt_fragment_metadata, "fragment=metadata"}, + {Opt_fragment_all, "fragment=all"}, +#endif {Opt_err, NULL}, }; @@ -721,6 +729,22 @@ int btrfs_parse_options(struct btrfs_root *root, char *options) info->commit_interval = BTRFS_DEFAULT_COMMIT_INTERVAL; } break; +#ifdef CONFIG_BTRFS_DEBUG + case Opt_fragment_all: + btrfs_info(root->fs_info, "fragmenting all space"); + btrfs_set_opt(info->mount_opt, FRAGMENT_DATA); + btrfs_set_opt(info->mount_opt, FRAGMENT_METADATA); + break; + case Opt_fragment_metadata: + btrfs_info(root->fs_info, "fragmenting metadata"); + btrfs_set_opt(info->mount_opt, + FRAGMENT_METADATA); + break; + case Opt_fragment_data: + btrfs_info(root->fs_info, "fragmenting data"); + btrfs_set_opt(info->mount_opt, FRAGMENT_DATA); + break; +#endif case Opt_err: btrfs_info(root->fs_info, "unrecognized mount option '%s'", p); ret = -EINVAL; @@ -1172,6 +1196,12 @@ static int btrfs_show_options(struct seq_file *seq, struct dentry *dentry) seq_puts(seq, ",fatal_errors=panic"); if (info->commit_interval != BTRFS_DEFAULT_COMMIT_INTERVAL) seq_printf(seq, ",commit=%d", info->commit_interval); +#ifdef CONFIG_BTRFS_DEBUG + if (btrfs_test_opt(root, FRAGMENT_DATA)) + seq_puts(seq, ",fragment=data"); + if (btrfs_test_opt(root, FRAGMENT_METADATA)) + seq_puts(seq, ",fragment=metadata"); +#endif seq_printf(seq, ",subvolid=%llu", BTRFS_I(d_inode(dentry))->root->root_key.objectid); seq_puts(seq, ",subvol="); diff --git a/fs/btrfs/tests/free-space-tests.c b/fs/btrfs/tests/free-space-tests.c index 2299bfde39ee..c8c3d70c31ff 100644 --- a/fs/btrfs/tests/free-space-tests.c +++ b/fs/btrfs/tests/free-space-tests.c @@ -19,6 +19,7 @@ #include #include "btrfs-tests.h" #include "../ctree.h" +#include "../disk-io.h" #include "../free-space-cache.h" #define BITS_PER_BITMAP (PAGE_CACHE_SIZE * 8) @@ -35,6 +36,12 @@ static struct btrfs_block_group_cache *init_test_block_group(void) kfree(cache); return NULL; } + cache->fs_info = btrfs_alloc_dummy_fs_info(); + if (!cache->fs_info) { + kfree(cache->free_space_ctl); + kfree(cache); + return NULL; + } cache->key.objectid = 0; cache->key.offset = 1024 * 1024 * 1024; @@ -879,7 +886,8 @@ test_steal_space_from_bitmap_to_extent(struct btrfs_block_group_cache *cache) int btrfs_test_free_space_cache(void) { struct btrfs_block_group_cache *cache; - int ret; + struct btrfs_root *root = NULL; + int ret = -ENOMEM; test_msg("Running btrfs free space cache tests\n"); @@ -889,6 +897,17 @@ int btrfs_test_free_space_cache(void) return 0; } + root = btrfs_alloc_dummy_root(); + if (!root) + goto out; + + root->fs_info = btrfs_alloc_dummy_fs_info(); + if (!root->fs_info) + goto out; + + root->fs_info->extent_root = root; + cache->fs_info = root->fs_info; + ret = test_extents(cache); if (ret) goto out; @@ -904,6 +923,7 @@ out: __btrfs_remove_free_space_cache(cache->free_space_ctl); kfree(cache->free_space_ctl); kfree(cache); + btrfs_free_dummy_root(root); test_msg("Free space cache tests finished\n"); return ret; }