On 02/03/2018 05:21 AM, Ming Lei wrote: > Hi All, > > This patchset supports global tags which was started by Hannes originally: > > https://marc.info/?l=linux-block&m=149132580511346&w=2 > > Also inroduce 'force_blk_mq' to 'struct scsi_host_template', so that > driver can avoid to support two IO paths(legacy and blk-mq), especially > recent discusion mentioned that SCSI_MQ will be enabled at default soon. > > https://marc.info/?l=linux-scsi&m=151727684915589&w=2 > > With the above two changes, it should be easier to convert SCSI drivers' > reply queue into blk-mq's hctx, then the automatic irq affinity issue can > be solved easily, please see detailed descrption in commit log. > > Also drivers may require to complete request on the submission CPU > for avoiding hard/soft deadlock, which can be done easily with blk_mq > too. > > https://marc.info/?t=151601851400001&r=1&w=2 > > The final patch uses the introduced 'force_blk_mq' to fix virtio_scsi > so that IO hang issue can be avoided inside legacy IO path, this issue is > a bit generic, at least HPSA/virtio-scsi are found broken with v4.15+. > > Thanks > Ming > > Ming Lei (5): > blk-mq: tags: define several fields of tags as pointer > blk-mq: introduce BLK_MQ_F_GLOBAL_TAGS > block: null_blk: introduce module parameter of 'g_global_tags' > scsi: introduce force_blk_mq > scsi: virtio_scsi: fix IO hang by irq vector automatic affinity > > block/bfq-iosched.c | 4 +-- > block/blk-mq-debugfs.c | 11 ++++---- > block/blk-mq-sched.c | 2 +- > block/blk-mq-tag.c | 67 +++++++++++++++++++++++++++++----------------- > block/blk-mq-tag.h | 15 ++++++++--- > block/blk-mq.c | 31 ++++++++++++++++----- > block/blk-mq.h | 3 ++- > block/kyber-iosched.c | 2 +- > drivers/block/null_blk.c | 6 +++++ > drivers/scsi/hosts.c | 1 + > drivers/scsi/virtio_scsi.c | 59 +++------------------------------------- > include/linux/blk-mq.h | 2 ++ > include/scsi/scsi_host.h | 3 +++ > 13 files changed, 105 insertions(+), 101 deletions(-) > Thanks Ming for picking this up. I'll give it a shot and see how it behaves on other hardware. Cheers, Hannes -- Dr. Hannes Reinecke Teamlead Storage & Networking hare@xxxxxxx +49 911 74053 688 SUSE LINUX GmbH, Maxfeldstr. 5, 90409 Nürnberg GF: F. Imendörffer, J. Smithard, J. Guild, D. Upmanyu, G. Norton HRB 21284 (AG Nürnberg)
