From b9473439d3e84d9fc1a0a83faca69cc1b7566341 Mon Sep 17 00:00:00 2001 From: Chris Mason Date: Fri, 13 Mar 2009 11:00:37 -0400 Subject: Btrfs: leave btree locks spinning more often btrfs_mark_buffer dirty would set dirty bits in the extent_io tree for the buffers it was dirtying. This may require a kmalloc and it was not atomic. So, anyone who called btrfs_mark_buffer_dirty had to set any btree locks they were holding to blocking first. This commit changes dirty tracking for extent buffers to just use a flag in the extent buffer. Now that we have one and only one extent buffer per page, this can be safely done without losing dirty bits along the way. This also introduces a path->leave_spinning flag that callers of btrfs_search_slot can use to indicate they will properly deal with a path returned where all the locks are spinning instead of blocking. Many of the btree search callers now expect spinning paths, resulting in better btree concurrency overall. Signed-off-by: Chris Mason --- fs/btrfs/extent_io.c | 51 +++++++++------------------------------------------ 1 file changed, 9 insertions(+), 42 deletions(-) (limited to 'fs/btrfs/extent_io.c') diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index ebe6b29e6069..08085af089e2 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -3124,20 +3124,15 @@ void free_extent_buffer(struct extent_buffer *eb) int clear_extent_buffer_dirty(struct extent_io_tree *tree, struct extent_buffer *eb) { - int set; unsigned long i; unsigned long num_pages; struct page *page; - u64 start = eb->start; - u64 end = start + eb->len - 1; - - set = clear_extent_dirty(tree, start, end, GFP_NOFS); num_pages = num_extent_pages(eb->start, eb->len); for (i = 0; i < num_pages; i++) { page = extent_buffer_page(eb, i); - if (!set && !PageDirty(page)) + if (!PageDirty(page)) continue; lock_page(page); @@ -3146,22 +3141,6 @@ int clear_extent_buffer_dirty(struct extent_io_tree *tree, else set_page_private(page, EXTENT_PAGE_PRIVATE); - /* - * if we're on the last page or the first page and the - * block isn't aligned on a page boundary, do extra checks - * to make sure we don't clean page that is partially dirty - */ - if ((i == 0 && (eb->start & (PAGE_CACHE_SIZE - 1))) || - ((i == num_pages - 1) && - ((eb->start + eb->len) & (PAGE_CACHE_SIZE - 1)))) { - start = (u64)page->index << PAGE_CACHE_SHIFT; - end = start + PAGE_CACHE_SIZE - 1; - if (test_range_bit(tree, start, end, - EXTENT_DIRTY, 0)) { - unlock_page(page); - continue; - } - } clear_page_dirty_for_io(page); spin_lock_irq(&page->mapping->tree_lock); if (!PageDirty(page)) { @@ -3187,29 +3166,13 @@ int set_extent_buffer_dirty(struct extent_io_tree *tree, { unsigned long i; unsigned long num_pages; + int was_dirty = 0; + was_dirty = test_and_set_bit(EXTENT_BUFFER_DIRTY, &eb->bflags); num_pages = num_extent_pages(eb->start, eb->len); - for (i = 0; i < num_pages; i++) { - struct page *page = extent_buffer_page(eb, i); - /* writepage may need to do something special for the - * first page, we have to make sure page->private is - * properly set. releasepage may drop page->private - * on us if the page isn't already dirty. - */ - lock_page(page); - if (i == 0) { - set_page_extent_head(page, eb->len); - } else if (PagePrivate(page) && - page->private != EXTENT_PAGE_PRIVATE) { - set_page_extent_mapped(page); - } + for (i = 0; i < num_pages; i++) __set_page_dirty_nobuffers(extent_buffer_page(eb, i)); - set_extent_dirty(tree, page_offset(page), - page_offset(page) + PAGE_CACHE_SIZE - 1, - GFP_NOFS); - unlock_page(page); - } - return 0; + return was_dirty; } int clear_extent_buffer_uptodate(struct extent_io_tree *tree, @@ -3789,6 +3752,10 @@ int try_release_extent_buffer(struct extent_io_tree *tree, struct page *page) ret = 0; goto out; } + if (test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags)) { + ret = 0; + goto out; + } /* at this point we can safely release the extent buffer */ num_pages = num_extent_pages(eb->start, eb->len); for (i = 0; i < num_pages; i++) -- cgit v1.2.2 From 93dbfad7ac647d4f00354893fe93e8a55be114d5 Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Fri, 3 Apr 2009 10:33:45 -0400 Subject: Btrfs: fix __ucmpdi2 compile bug on 32 bit builds We get this on 32 builds: fs/built-in.o: In function `extent_fiemap': (.text+0x1019f2): undefined reference to `__ucmpdi2' Happens because of a switch statement with a 64 bit argument. Convert this to an if statement to fix this. Signed-off-by: Heiko Carstens Signed-off-by: Chris Mason --- fs/btrfs/extent_io.c | 16 +++++----------- 1 file changed, 5 insertions(+), 11 deletions(-) (limited to 'fs/btrfs/extent_io.c') diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index 08085af089e2..eb2bee8b7fbf 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -2884,25 +2884,19 @@ int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, disko = 0; flags = 0; - switch (em->block_start) { - case EXTENT_MAP_LAST_BYTE: + if (em->block_start == EXTENT_MAP_LAST_BYTE) { end = 1; flags |= FIEMAP_EXTENT_LAST; - break; - case EXTENT_MAP_HOLE: + } else if (em->block_start == EXTENT_MAP_HOLE) { flags |= FIEMAP_EXTENT_UNWRITTEN; - break; - case EXTENT_MAP_INLINE: + } else if (em->block_start == EXTENT_MAP_INLINE) { flags |= (FIEMAP_EXTENT_DATA_INLINE | FIEMAP_EXTENT_NOT_ALIGNED); - break; - case EXTENT_MAP_DELALLOC: + } else if (em->block_start == EXTENT_MAP_DELALLOC) { flags |= (FIEMAP_EXTENT_DELALLOC | FIEMAP_EXTENT_UNKNOWN); - break; - default: + } else { disko = em->block_start; - break; } if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) flags |= FIEMAP_EXTENT_ENCODED; -- cgit v1.2.2