NTFS: Improve scalability by changing the driver global spin lock in
fs/ntfs/aops.c::ntfs_end_buffer_async_read() to a bit spin lock
in the first buffer head of a page.
Signed-off-by: Anton Altaparmakov <aia21@cantab.net>
diff --git a/fs/ntfs/aops.c b/fs/ntfs/aops.c
index 52e1aff..950b686 100644
--- a/fs/ntfs/aops.c
+++ b/fs/ntfs/aops.c
@@ -55,9 +55,8 @@
*/
static void ntfs_end_buffer_async_read(struct buffer_head *bh, int uptodate)
{
- static DEFINE_SPINLOCK(page_uptodate_lock);
unsigned long flags;
- struct buffer_head *tmp;
+ struct buffer_head *first, *tmp;
struct page *page;
ntfs_inode *ni;
int page_uptodate = 1;
@@ -89,11 +88,13 @@
}
} else {
clear_buffer_uptodate(bh);
+ SetPageError(page);
ntfs_error(ni->vol->sb, "Buffer I/O error, logical block %llu.",
(unsigned long long)bh->b_blocknr);
- SetPageError(page);
}
- spin_lock_irqsave(&page_uptodate_lock, flags);
+ first = page_buffers(page);
+ local_irq_save(flags);
+ bit_spin_lock(BH_Uptodate_Lock, &first->b_state);
clear_buffer_async_read(bh);
unlock_buffer(bh);
tmp = bh;
@@ -108,7 +109,8 @@
}
tmp = tmp->b_this_page;
} while (tmp != bh);
- spin_unlock_irqrestore(&page_uptodate_lock, flags);
+ bit_spin_unlock(BH_Uptodate_Lock, &first->b_state);
+ local_irq_restore(flags);
/*
* If none of the buffers had errors then we can set the page uptodate,
* but we first have to perform the post read mst fixups, if the
@@ -141,7 +143,8 @@
unlock_page(page);
return;
still_busy:
- spin_unlock_irqrestore(&page_uptodate_lock, flags);
+ bit_spin_unlock(BH_Uptodate_Lock, &first->b_state);
+ local_irq_restore(flags);
return;
}