On 26/11/2019 09:14, Hannes Reinecke wrote:
Hi all,
here now is an updated version of the v2 patchset from John Garry,
including the suggestions and reviews from the mailing list.
John, apologies for hijacking your work :-)
No worries as long as we can keep moving this forward.
The main diffence is that I've changed the bitmaps to be allocated
separately in all cases, and just set the pointer to the shared bitmap
for the hostwide tags case.
Yeah, I was considering this also.
I've also modified smartpqi and hpsa to take advantage of host_tags.
I did audit the iterators, and I _think_ they do the correct thing even
in the shared bitmap case. But then I might have overlooked things,
so feedback and reviews are welcome.
The one thing I'm not happy with is the debugfs interface; for shared
bitmaps all will be displaying essentially the same information, which
could be moved to a top-level directory. But that would change the
layout and I'm not sure if that buys us anything.
I was having a look at this. I'd say we need to still show which bits
are set per hctx.
Maybe we can do something like this:
a. In hctx_tags_bitmaphow() or other relevant functions, copy shared
sbitmap map into temp sbitmap map (maybe even the per-hctx sbitmap)
b. iterate over to unset bits not relevant to hctx in temp sbitmap map
c. then do sbitmap_show
Locking may be a bit tricky.
Thanks,
John
Differences to v2:
- Drop embedded tag bitmaps
- Do not share scheduling tags
- Add patches for hpsa and smartpqi
Differences to v1:
- Use a shared sbitmap, and not a separate shared tags (a big change!)
- Drop request.shared_tag
- Add RB tags
Hannes Reinecke (4):
blk-mq: Use a pointer for sbitmap
scsi: Add template flag 'host_tagset'
smartpqi: enable host tagset
hpsa: switch to using blk-mq
John Garry (3):
blk-mq: Remove some unused function arguments
blk-mq: Facilitate a shared sbitmap per tagset
scsi: hisi_sas: Switch v3 hw to MQ
Ming Lei (1):
blk-mq: rename BLK_MQ_F_TAG_SHARED as BLK_MQ_F_TAG_QUEUE_SHARED
block/bfq-iosched.c | 4 +-
block/blk-mq-debugfs.c | 10 ++--
block/blk-mq-sched.c | 8 ++-
block/blk-mq-tag.c | 104 ++++++++++++++++++++++-----------
block/blk-mq-tag.h | 18 +++---
block/blk-mq.c | 80 ++++++++++++++++---------
block/blk-mq.h | 9 ++-
block/kyber-iosched.c | 4 +-
drivers/scsi/hisi_sas/hisi_sas.h | 3 +-
drivers/scsi/hisi_sas/hisi_sas_main.c | 36 ++++++------
drivers/scsi/hisi_sas/hisi_sas_v3_hw.c | 86 +++++++++++----------------
drivers/scsi/hpsa.c | 44 +++-----------
drivers/scsi/hpsa.h | 1 -
drivers/scsi/scsi_lib.c | 2 +
drivers/scsi/smartpqi/smartpqi_init.c | 38 ++++++++----
include/linux/blk-mq.h | 9 ++-
include/scsi/scsi_host.h | 3 +
17 files changed, 260 insertions(+), 199 deletions(-)
