block: enable bio caching use for passthru IO
authorJens Axboe <axboe@kernel.dk>
Fri, 5 Aug 2022 22:43:09 +0000 (16:43 -0600)
committerJens Axboe <axboe@kernel.dk>
Mon, 22 Aug 2022 16:07:56 +0000 (10:07 -0600)
commit8af870aa5b84729d7a39f84226be6f84e4943d8f
tree846be7067a3243a20cfadb8182109176baef9699
parentf5d632d15e9e0a037339601680d82bb840f85d10
block: enable bio caching use for passthru IO

bdev based polled O_DIRECT is currently quite a bit faster than
passthru on the same device, and one of the reaons is that we're not
able to use the bio caching for passthru IO.

If REQ_POLLED is set on the request, use the fs bio set for grabbing a
bio from the caches, if available. This saves 5-6% of CPU over head
for polled passthru IO.

Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
block/blk-map.c