Changes since v1: - reintroduced original blk_poll() function that has been removed some time ago (Jens) - added fastpath calls to blk_mq_poll() in blk_poll() (Christoph, Jens) - incorporated code style fixes into md patch (Christoph) [1]: https://lore.kernel.org/linux-block/20200126044138.5066-1-andrzej.jakowski@xxxxxxxxxxxxxxx/T/#t --- IO polling is available on blk-mq devices. It is not possible to perform IO polling on stackable devices like MD. In this patch series we propose to reintroduce blk_poll() function. blk_poll() when called on stackable block device that supports polling will invoke its polling handler. Otherwise it will call blk_mq_poll() directly for fast accesses. This patch set also includes example implemetation of polling on MD RAID-0 volume. --- TODO: - introduce REQ_NOWAIT support for stackable devices in a separate patchset (Christoph) Andrzej Jakowski (1): block: reintroduce polling on bio level Artur Paszkiewicz (1): md: enable io polling block/blk-core.c | 28 ++++++++++++++++++++++++++++ block/blk-mq.c | 23 ++--------------------- block/blk-mq.h | 2 ++ drivers/md/md.c | 40 ++++++++++++++++++++++++++++++++++++---- include/linux/blkdev.h | 2 ++ 5 files changed, 70 insertions(+), 25 deletions(-) -- 2.20.1