From 993778306e7901a7286322f25c7c681dd47bede6 Mon Sep 17 00:00:00 2001 From: Ritesh Harjani Date: Wed, 20 May 2020 12:10:36 +0530 Subject: ext4: mballoc: use lock for checking free blocks while retrying Currently while doing block allocation grp->bb_free may be getting modified if discard is happening in parallel. For e.g. consider a case where there are lot of threads who have preallocated lot of blocks and there is a thread which is trying to discard all of this group's PA. Now it could happen that we see all of those group's bb_free is zero and fail the allocation while there is sufficient space if we free up all the PA. So this patch adds another flag "EXT4_MB_STRICT_CHECK" which will be set if we are unable to allocate any blocks in the first try (since we may not have considered blocks about to be discarded from PA lists). So during retry attempt to allocate blocks we will use ext4_lock_group() for checking if the group is good or not. Signed-off-by: Ritesh Harjani Link: https://lore.kernel.org/r/9cb740a117c958c36596f167b12af1beae9a68b7.1589955723.git.riteshh@linux.ibm.com Signed-off-by: Theodore Ts'o --- include/trace/events/ext4.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'include/trace') diff --git a/include/trace/events/ext4.h b/include/trace/events/ext4.h index 280475c1cecc..cc41d692ae8e 100644 --- a/include/trace/events/ext4.h +++ b/include/trace/events/ext4.h @@ -35,7 +35,8 @@ struct partial_cluster; { EXT4_MB_DELALLOC_RESERVED, "DELALLOC_RESV" }, \ { EXT4_MB_STREAM_ALLOC, "STREAM_ALLOC" }, \ { EXT4_MB_USE_ROOT_BLOCKS, "USE_ROOT_BLKS" }, \ - { EXT4_MB_USE_RESERVED, "USE_RESV" }) + { EXT4_MB_USE_RESERVED, "USE_RESV" }, \ + { EXT4_MB_STRICT_CHECK, "STRICT_CHECK" }) #define show_map_flags(flags) __print_flags(flags, "|", \ { EXT4_GET_BLOCKS_CREATE, "CREATE" }, \ -- cgit v1.2.3-59-g8ed1b