[WIP PATCHSET 0/4] WIP branch for bfq-mq

[Paolo Valente]

Hi,

I have finally pushed here [1] the current WIP branch of bfq for
blk-mq, which I have tentatively named bfq-mq.

This branch *IS NOT* meant for merging into mainline and contain code
that mau easily violate code style, and not only, in many
places. Commits implement the following main steps:
1) Add the last version of bfq for blk
2) Clone bfq source files into identical bfq-mq source files
3) Modify bfq-mq files to get a working version of bfq for blk-mq
(cgroups support not yet functional)

In my intentions, the main goals of this branch are:

1) Show, as soon as I could, the changes I made to let bfq-mq comply
with blk-mq-sched framework. I though this could be particularly
useful for Jens, being BFQ identical to CFQ in terms of hook
interfaces and io-context handling, and almost identical in terms
request-merging.

2) Enable people to test this first version bfq-mq. Code is purposely
overfull of log messages and invariant checks that halt the system on
failure (lock assertions, BUG_ONs, ...).

To make it easier to revise commits, I'm sending the patches that
transform bfq into bfq-mq (last four patches in the branch [1]). They
work on two files, bfq-mq-iosched.c and bfq-mq.h, which, at the
beginning, are just copies of bfq-iosched.c and bfq.h.

Thanks,
Paolo

[1] https://github.com/Algodev-github/bfq-mq

Paolo Valente (4):
  blk-mq: pass bio to blk_mq_sched_get_rq_priv
  Move thinktime from bic to bfqq
  Embed bfq-ioc.c and add locking on request queue
  Modify interface and operation to comply with blk-mq-sched

 block/bfq-cgroup.c       |   4 -
 block/bfq-mq-iosched.c   | 852 +++++++++++++++++++++++++++++------------------
 block/bfq-mq.h           |  65 ++--
 block/blk-mq-sched.c     |   8 +-
 block/blk-mq-sched.h     |   5 +-
 include/linux/elevator.h |   2 +-
 6 files changed, 567 insertions(+), 369 deletions(-)

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2.10.0