[PATCH] invalidate_bdev() speedup
We can immediately bail from invalidate_bdev() if the blockdev has no
pagecache.
This solves the huge IPI storms which hald is causing on the big ia64
machines when it polls CDROM drives.
Acked-by: Jes Sorensen <jes@sgi.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/fs/buffer.c b/fs/buffer.c
index 3660dcb..71649ef 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -470,13 +470,18 @@
pass does the actual I/O. */
void invalidate_bdev(struct block_device *bdev, int destroy_dirty_buffers)
{
+ struct address_space *mapping = bdev->bd_inode->i_mapping;
+
+ if (mapping->nrpages == 0)
+ 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_inode_pages(bdev->bd_inode->i_mapping);
+ invalidate_inode_pages(mapping);
}
/*
