[PATCH v3 2/2] blk-mq: Add a polling specific stats function

[Stephen Bates]

> You can, but it won't do much good since v3 is already applied. Any
> further changes must be incremental.

BTW getting a compile error from the Kyber code in for-4.12/block due to the fact we now return a signed from the bucket function…

batesste at ubuntu64-batesste:~/kernel/linux$ make -j 2 all
  CHK     include/config/kernel.release
  CHK     include/generated/uapi/linux/version.h
  CHK     include/generated/utsrelease.h
  CHK     include/generated/timeconst.h
  CHK     include/generated/bounds.h
  CHK     include/generated/asm-offsets.h
  CALL    scripts/checksyscalls.sh
  CHK     include/generated/compile.h
  CC      block/kyber-iosched.o
block/kyber-iosched.c: In function ‘kyber_queue_data_alloc’:
block/kyber-iosched.c:295:57: error: passing argument 2 of ‘blk_stat_alloc_callback’ from incompatible pointer type [-Werror=incompatible-pointer-types]
  kqd->cb = blk_stat_alloc_callback(kyber_stat_timer_fn, rq_sched_domain,
                                                         ^
In file included from block/blk-mq.h:4:0,
                 from block/blk.h:6,
                 from block/kyber-iosched.c:27:
block/blk-stat.h:138:1: note: expected ‘int (*)(const struct request *)’ but argument is of type ‘unsigned int (*)(const struct request *)’
 blk_stat_alloc_callback(void (*timer_fn)(struct blk_stat_callback *),
 ^
  CC      block/compat_ioctl.o
cc1: some warnings being treated as errors