On Sat, Sep 13, 2014 at 11:07 AM, Ming Lei <ming....@canonical.com> wrote: > Hi, > > As recent discussion, especially suggested by Christoph, this patchset > implements per-distpatch_queue flush machinery, so that: > > - current init_request and exit_request callbacks can > cover flush request too, then the buggy copying way of > initializing flush request's pdu can be fixed > > - flushing performance gets improved in case of multi hw-queue > > About 70% throughput improvement is observed in sync write > over multi dispatch-queue virtio-blk, see details in commit log > of patch 10/10. > > This patchset can be pulled from below tree too: > > git://kernel.ubuntu.com/ming/linux.git v3.17-block-dev_v3 > > V3: > - don't return failure code from blk_alloc_flush_queue() to > avoid freeing invalid buffer in case of allocation failure > - remove blk_init_flush() and blk_exit_flush() > - remove unnecessary WARN_ON() from blk_alloc_flush_queue()
Looks there are still two problems in V3: - blk_free_flush_queue() should be called only for legacy queue after the patch 10's conversion - pdu copy should be removed from blk_mq_clone_flush_request() I will post V4 once these two problems are fixed. Thanks, > > V2: > - refactor blk_mq_init_hw_queues() and its pair, also it is a fix > on failure path, so that conversion to per-queue flush becomes simple. > - allocate/initialize flush queue in blk_mq_init_hw_queues() > - add sync write tests on virtio-blk which is backed by SSD image > > V1: > - commit log typo fix > - introduce blk_alloc_flush_queue() and its pair earlier, so > that patch 5 and 8 become easier for review > > block/blk-core.c | 12 ++-- > block/blk-flush.c | 129 +++++++++++++++++++++++++------------- > block/blk-mq.c | 160 > ++++++++++++++++++++++++++++++------------------ > block/blk-mq.h | 1 - > block/blk-sysfs.c | 4 +- > block/blk.h | 35 ++++++++++- > include/linux/blk-mq.h | 2 + > include/linux/blkdev.h | 10 +-- > 8 files changed, 230 insertions(+), 123 deletions(-) > > > > Thanks, > -- > Ming Lei > > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/