[PATCH 4.4 46/65] gfs2: Revert "Fix loop in gfs2_rbm_find"

Greg Kroah-Hartman
2019-02-04T10:42:18Z

From: Andreas Gruenbacher <agruenba@redhat.com>

commit e74c98ca2d6ae4376cc15fa2a22483430909d96b upstream.

This reverts commit 2d29f6b96d8f80322ed2dd895bca590491c38d34.

It turns out that the fix can lead to a ~20 percent performance regression
in initial writes to the page cache according to iozone. Let's revert this
for now to have more time for a proper fix.

Cc: stable@vger.kernel.org # v3.13+
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
fs/gfs2/rgrp.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/fs/gfs2/rgrp.c
+++ b/fs/gfs2/rgrp.c
@@ -1720,9 +1720,9 @@ static int gfs2_rbm_find(struct gfs2_rbm
goto next_iter;
}
if (ret == -E2BIG) {
- n += rbm->bii - initial_bii;
rbm->bii = 0;
rbm->offset = 0;
+ n += (rbm->bii - initial_bii);
goto res_covered_end_of_rgrp;
}
return ret;