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author | Chris Mason <chris.mason@oracle.com> | 2008-04-18 14:29:50 (GMT) |
---|---|---|
committer | Chris Mason <chris.mason@oracle.com> | 2008-09-25 15:04:02 (GMT) |
commit | 7b13b7b119c932a5eca486db4113f4c1fe3b97a8 (patch) | |
tree | cf4432c69f660f0c22c1b6415c0d907ba6d44c8a | |
parent | 7ae9c09d8f001eb19ee2ba219dc5c3d4f6d60614 (diff) | |
download | linux-fsl-qoriq-7b13b7b119c932a5eca486db4113f4c1fe3b97a8.tar.xz |
Btrfs: Don't drop extent_map cache during releasepage on the btree inode
The btree inode should only have a single extent_map in the cache,
it doesn't make sense to ever drop it.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
-rw-r--r-- | fs/btrfs/disk-io.c | 23 | ||||
-rw-r--r-- | fs/btrfs/extent_io.c | 38 | ||||
-rw-r--r-- | fs/btrfs/extent_io.h | 3 |
3 files changed, 44 insertions, 20 deletions
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 76ee7a4..2de2b00 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -76,13 +76,12 @@ struct extent_map *btree_get_extent(struct inode *inode, struct page *page, struct extent_map *em; int ret; -again: spin_lock(&em_tree->lock); em = lookup_extent_mapping(em_tree, start, len); spin_unlock(&em_tree->lock); - if (em) { + if (em) goto out; - } + em = alloc_extent_map(GFP_NOFS); if (!em) { em = ERR_PTR(-ENOMEM); @@ -95,15 +94,21 @@ again: spin_lock(&em_tree->lock); ret = add_extent_mapping(em_tree, em); - spin_unlock(&em_tree->lock); - if (ret == -EEXIST) { free_extent_map(em); - em = NULL; - goto again; + em = lookup_extent_mapping(em_tree, start, len); + if (em) + ret = 0; + else + ret = -EIO; } else if (ret) { - em = ERR_PTR(ret); + free_extent_map(em); + em = NULL; } + spin_unlock(&em_tree->lock); + + if (ret) + em = ERR_PTR(ret); out: return em; } @@ -496,7 +501,7 @@ static int btree_releasepage(struct page *page, gfp_t gfp_flags) } tree = &BTRFS_I(page->mapping->host)->io_tree; map = &BTRFS_I(page->mapping->host)->extent_tree; - ret = try_release_extent_mapping(map, tree, page, gfp_flags); + ret = try_release_extent_state(map, tree, page, gfp_flags); if (ret == 1) { invalidate_extent_lru(tree, page_offset(page), PAGE_CACHE_SIZE); ClearPagePrivate(page); diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index a984a7b..81f8b4f 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -2464,6 +2464,31 @@ err: EXPORT_SYMBOL(extent_prepare_write); /* + * a helper for releasepage, this tests for areas of the page that + * are locked or under IO and drops the related state bits if it is safe + * to drop the page. + */ +int try_release_extent_state(struct extent_map_tree *map, + struct extent_io_tree *tree, struct page *page, + gfp_t mask) +{ + u64 start = (u64)page->index << PAGE_CACHE_SHIFT; + u64 end = start + PAGE_CACHE_SIZE - 1; + int ret = 1; + + if (test_range_bit(tree, start, end, EXTENT_IOBITS, 0)) + ret = 0; + else { + if ((mask & GFP_NOFS) == GFP_NOFS) + mask = GFP_NOFS; + clear_extent_bit(tree, start, end, EXTENT_UPTODATE, + 1, 1, mask); + } + return ret; +} +EXPORT_SYMBOL(try_release_extent_state); + +/* * a helper for releasepage. As long as there are no locked extents * in the range corresponding to the page, both state records and extent * map records are removed @@ -2475,8 +2500,7 @@ int try_release_extent_mapping(struct extent_map_tree *map, struct extent_map *em; u64 start = (u64)page->index << PAGE_CACHE_SHIFT; u64 end = start + PAGE_CACHE_SIZE - 1; - u64 orig_start = start; - int ret = 1; + if ((mask & __GFP_WAIT) && page->mapping->host->i_size > 16 * 1024 * 1024) { u64 len; @@ -2507,15 +2531,7 @@ int try_release_extent_mapping(struct extent_map_tree *map, free_extent_map(em); } } - if (test_range_bit(tree, orig_start, end, EXTENT_IOBITS, 0)) - ret = 0; - else { - if ((mask & GFP_NOFS) == GFP_NOFS) - mask = GFP_NOFS; - clear_extent_bit(tree, orig_start, end, EXTENT_UPTODATE, - 1, 1, mask); - } - return ret; + return try_release_extent_state(map, tree, page, mask); } EXPORT_SYMBOL(try_release_extent_mapping); diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h index 232300d..e483461 100644 --- a/fs/btrfs/extent_io.h +++ b/fs/btrfs/extent_io.h @@ -110,6 +110,9 @@ void extent_io_tree_empty_lru(struct extent_io_tree *tree); int try_release_extent_mapping(struct extent_map_tree *map, struct extent_io_tree *tree, struct page *page, gfp_t mask); +int try_release_extent_state(struct extent_map_tree *map, + struct extent_io_tree *tree, struct page *page, + gfp_t mask); int lock_extent(struct extent_io_tree *tree, u64 start, u64 end, gfp_t mask); int unlock_extent(struct extent_io_tree *tree, u64 start, u64 end, gfp_t mask); int extent_read_full_page(struct extent_io_tree *tree, struct page *page, |