Hi,
Please review the 2 patches in this series. I'm left on-the-fence
about whether there is any point re-enabling "dm-mq stacked on old
.request_fn device(s)" -- especially given the awkward details
documented in the 1/2 patch header.
I welcome any feedback on this, thanks!
BTW, I tested these changes using mptest:
git://github.com/snitm/mptest.git
with the following permutations ('runtest' script tweaked before each
permutation):
echo N > /sys/module/scsi_mod/parameters/use_blk_mq
echo N > /sys/module/dm_mod/parameters/use_blk_mq
echo Y > /sys/module/scsi_mod/parameters/use_blk_mq
echo Y > /sys/module/dm_mod/parameters/use_blk_mq
echo Y > /sys/module/scsi_mod/parameters/use_blk_mq
echo N > /sys/module/dm_mod/parameters/use_blk_mq
echo N > /sys/module/scsi_mod/parameters/use_blk_mq
echo Y > /sys/module/dm_mod/parameters/use_blk_mq
Mike Snitzer (2):
dm rq: avoid deadlock if dm-mq is stacked on old .request_fn device(s)
dm rq: eliminate historic blk-mq and .request_fn queue stacking restrictions
drivers/md/dm-mpath.c | 16 ++++++++++++++--
drivers/md/dm-rq.c | 13 +++++--------
drivers/md/dm-table.c | 31 +++----------------------------
drivers/md/dm-target.c | 4 ++--
drivers/md/dm.h | 1 -
include/linux/device-mapper.h | 3 ++-
6 files changed, 26 insertions(+), 42 deletions(-)
--
2.10.1
