jbd2: revert must-not-fail allocation loops back to GFP_NOFAIL
This basically reverts 47def82672b3 (jbd2: Remove __GFP_NOFAIL from jbd2
layer). The deprecation of __GFP_NOFAIL was a bad choice because it led
to open coding the endless loop around the allocator rather than
removing the dependency on the non failing allocation. So the
deprecation was a clear failure and the reality tells us that
__GFP_NOFAIL is not even close to go away.
It is still true that __GFP_NOFAIL allocations are generally discouraged
and new uses should be evaluated and an alternative (pre-allocations or
reservations) should be considered but it doesn't make any sense to lie
the allocator about the requirements. Allocator can take steps to help
making a progress if it knows the requirements.
Signed-off-by: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Acked-by: David Rientjes <rientjes@google.com>
diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c
index b96bd80..0bc333b 100644
--- a/fs/jbd2/journal.c
+++ b/fs/jbd2/journal.c
@@ -371,16 +371,7 @@
*/
J_ASSERT_BH(bh_in, buffer_jbddirty(bh_in));
-retry_alloc:
- new_bh = alloc_buffer_head(GFP_NOFS);
- if (!new_bh) {
- /*
- * Failure is not an option, but __GFP_NOFAIL is going
- * away; so we retry ourselves here.
- */
- congestion_wait(BLK_RW_ASYNC, HZ/50);
- goto retry_alloc;
- }
+ new_bh = alloc_buffer_head(GFP_NOFS|__GFP_NOFAIL);
/* keep subsequent assertions sane */
atomic_set(&new_bh->b_count, 1);