[PATCH] sync_inodes_sb() stack reduction

Reduce stack consumption in sync_inodes_sb() via read_page_state().

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index 71176e4dc76f65a8f7d394f02d2e81d248eca6ac..5f3ccf9890531a6a4f23cb7d7293def4155179eb 100644 (file)
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -433,18 +433,15 @@ restart:
  */
 void sync_inodes_sb(struct super_block *sb, int wait)
 {
-       struct page_state ps;
        struct writeback_control wbc = {
-               .bdi            = NULL,
                .sync_mode      = wait ? WB_SYNC_ALL : WB_SYNC_HOLD,
-               .older_than_this = NULL,
-               .nr_to_write    = 0,
        };
+       unsigned long nr_dirty = read_page_state(nr_dirty);
+       unsigned long nr_unstable = read_page_state(nr_unstable);
 
-       get_page_state(&ps);
-       wbc.nr_to_write = ps.nr_dirty + ps.nr_unstable +
+       wbc.nr_to_write = nr_dirty + nr_unstable +
                        (inodes_stat.nr_inodes - inodes_stat.nr_unused) +
-                       ps.nr_dirty + ps.nr_unstable;
+                       nr_dirty + nr_unstable;
        wbc.nr_to_write += wbc.nr_to_write / 2;         /* Bit more for luck */
        spin_lock(&inode_lock);
        sync_sb_inodes(sb, &wbc);