From 3d67f2d7c0fb28b0eb6a6aa100b190526a971ad9 Mon Sep 17 00:00:00 2001 From: Nick Piggin Date: Sun, 6 May 2007 14:49:05 -0700 Subject: fs: buffer don't PageUptodate without page locked __block_write_full_page is calling SetPageUptodate without the page locked. This is unusual, but not incorrect, as PG_writeback is still set. However the next patch will require that SetPageUptodate always be called with the page locked. Simply don't bother setting the page uptodate in this case (it is unusual that the write path does such a thing anyway). Instead just leave it to the read side to bring the page uptodate when it notices that all buffers are uptodate. Signed-off-by: Nick Piggin Cc: Hugh Dickins Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/buffer.c | 11 +---------- 1 file changed, 1 insertion(+), 10 deletions(-) (limited to 'fs/buffer.c') diff --git a/fs/buffer.c b/fs/buffer.c index 1d0852fa728..dcc5faa573b 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -1700,17 +1700,8 @@ done: * clean. Someone wrote them back by hand with * ll_rw_block/submit_bh. A rare case. */ - int uptodate = 1; - do { - if (!buffer_uptodate(bh)) { - uptodate = 0; - break; - } - bh = bh->b_this_page; - } while (bh != head); - if (uptodate) - SetPageUptodate(page); end_page_writeback(page); + /* * The page and buffer_heads can be released at any time from * here on. -- cgit From f98393a64ca1392130724c3acb4e3f325801d2b6 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Sun, 6 May 2007 14:49:54 -0700 Subject: mm: remove destroy_dirty_buffers from invalidate_bdev() Remove the destroy_dirty_buffers argument from invalidate_bdev(), it hasn't been used in 6 years (so akpm says). find * -name \*.[ch] | xargs grep -l invalidate_bdev | while read file; do quilt add $file; sed -ie 's/invalidate_bdev(\([^,]*\),[^)]*)/invalidate_bdev(\1)/g' $file; done Signed-off-by: Peter Zijlstra Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/buffer.c | 7 +------ 1 file changed, 1 insertion(+), 6 deletions(-) (limited to 'fs/buffer.c') diff --git a/fs/buffer.c b/fs/buffer.c index dcc5faa573b..630df3e6fe0 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -333,7 +333,7 @@ out: we think the disk contains more recent information than the buffercache. The update == 1 pass marks the buffers we need to update, the update == 2 pass does the actual I/O. */ -void invalidate_bdev(struct block_device *bdev, int destroy_dirty_buffers) +void invalidate_bdev(struct block_device *bdev) { struct address_space *mapping = bdev->bd_inode->i_mapping; @@ -341,11 +341,6 @@ void invalidate_bdev(struct block_device *bdev, int destroy_dirty_buffers) return; invalidate_bh_lrus(); - /* - * FIXME: what about destroy_dirty_buffers? - * We really want to use invalidate_inode_pages2() for - * that, but not until that's cleaned up. - */ invalidate_mapping_pages(mapping, 0, -1); } -- cgit From f9a14399aea13830d8af6798a53207bb0a900945 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Sun, 6 May 2007 14:49:55 -0700 Subject: mm: optimize kill_bdev() Remove duplicate work in kill_bdev(). It currently invalidates and then truncates the bdev's mapping. invalidate_mapping_pages() will opportunistically remove pages from the mapping. And truncate_inode_pages() will forcefully remove all pages. The only thing truncate doesn't do is flush the bh lrus. So do that explicitly. This avoids (very unlikely) but possible invalid lookup results if the same bdev is quickly re-issued. It also will prevent extreme kernel latencies which are observed when blockdevs which have a large amount of pagecache are unmounted, by avoiding invalidate_mapping_pages() on that path. invalidate_mapping_pages() has no cond_resched (it can be called under spinlock), whereas truncate_inode_pages() has one. [akpm@linux-foundation.org: restore nrpages==0 optimisation] Signed-off-by: Peter Zijlstra Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/buffer.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'fs/buffer.c') diff --git a/fs/buffer.c b/fs/buffer.c index 630df3e6fe0..80291aad6de 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -44,7 +44,6 @@ #include static int fsync_buffers_list(spinlock_t *lock, struct list_head *list); -static void invalidate_bh_lrus(void); #define BH_ENTRY(list) list_entry((list), struct buffer_head, b_assoc_buffers) @@ -1403,7 +1402,7 @@ static void invalidate_bh_lru(void *arg) put_cpu_var(bh_lrus); } -static void invalidate_bh_lrus(void) +void invalidate_bh_lrus(void) { on_each_cpu(invalidate_bh_lru, NULL, 1, 1); } -- cgit From 50953fe9e00ebbeffa032a565ab2f08312d51a87 Mon Sep 17 00:00:00 2001 From: Christoph Lameter Date: Sun, 6 May 2007 14:50:16 -0700 Subject: slab allocators: Remove SLAB_DEBUG_INITIAL flag I have never seen a use of SLAB_DEBUG_INITIAL. It is only supported by SLAB. I think its purpose was to have a callback after an object has been freed to verify that the state is the constructor state again? The callback is performed before each freeing of an object. I would think that it is much easier to check the object state manually before the free. That also places the check near the code object manipulation of the object. Also the SLAB_DEBUG_INITIAL callback is only performed if the kernel was compiled with SLAB debugging on. If there would be code in a constructor handling SLAB_DEBUG_INITIAL then it would have to be conditional on SLAB_DEBUG otherwise it would just be dead code. But there is no such code in the kernel. I think SLUB_DEBUG_INITIAL is too problematic to make real use of, difficult to understand and there are easier ways to accomplish the same effect (i.e. add debug code before kfree). There is a related flag SLAB_CTOR_VERIFY that is frequently checked to be clear in fs inode caches. Remove the pointless checks (they would even be pointless without removeal of SLAB_DEBUG_INITIAL) from the fs constructors. This is the last slab flag that SLUB did not support. Remove the check for unimplemented flags from SLUB. Signed-off-by: Christoph Lameter Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/buffer.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'fs/buffer.c') diff --git a/fs/buffer.c b/fs/buffer.c index 80291aad6de..7db24b9e544 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -2953,8 +2953,7 @@ EXPORT_SYMBOL(free_buffer_head); static void init_buffer_head(void *data, struct kmem_cache *cachep, unsigned long flags) { - if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) == - SLAB_CTOR_CONSTRUCTOR) { + if (flags & SLAB_CTOR_CONSTRUCTOR) { struct buffer_head * bh = (struct buffer_head *)data; memset(bh, 0, sizeof(*bh)); -- cgit