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dm mpath: simplify __must_push_back

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Remove micro-optimization that infers device is between presuspend and
resume (was done purely to avoid call to dm_noflush_suspending, which
isn't expensive anyway).

Remove flags argument since they are no longer checked.

And remove must_push_back_bio() since it was simply a call to
__must_push_back().

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
This commit is contained in:
Mike Snitzer 2020-05-26 16:06:56 -04:00
parent 27d49ac1dd
commit a862e4e215
1 changed files with 5 additions and 23 deletions
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28
drivers/md/dm-mpath.c
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@ -457,33 +457,15 @@ do { \
/*
* Check whether bios must be queued in the device-mapper core rather
* than here in the target.
*
* If MPATHF_QUEUE_IF_NO_PATH and MPATHF_SAVED_QUEUE_IF_NO_PATH hold
* the same value then we are not between multipath_presuspend()
* and multipath_resume() calls and we have no need to check
* for the DMF_NOFLUSH_SUSPENDING flag.
*/
static bool __must_push_back(struct multipath *m, unsigned long flags)
static bool __must_push_back(struct multipath *m)
{
return ((test_bit(MPATHF_QUEUE_IF_NO_PATH, &flags) !=
test_bit(MPATHF_SAVED_QUEUE_IF_NO_PATH, &flags)) &&
dm_noflush_suspending(m->ti));
return dm_noflush_suspending(m->ti);
}
/*
* Following functions use READ_ONCE to get atomic access to
* all m->flags to avoid taking spinlock
*/
static bool must_push_back_rq(struct multipath *m)
{
unsigned long flags = READ_ONCE(m->flags);
return test_bit(MPATHF_QUEUE_IF_NO_PATH, &flags) || __must_push_back(m, flags);
}
static bool must_push_back_bio(struct multipath *m)
{
unsigned long flags = READ_ONCE(m->flags);
return __must_push_back(m, flags);
return test_bit(MPATHF_QUEUE_IF_NO_PATH, &m->flags) || __must_push_back(m);
}
/*
@ -620,7 +602,7 @@ static int __multipath_map_bio(struct multipath *m, struct bio *bio,
return DM_MAPIO_SUBMITTED;
if (!pgpath) {
if (must_push_back_bio(m))
if (__must_push_back(m))
return DM_MAPIO_REQUEUE;
dm_report_EIO(m);
return DM_MAPIO_KILL;
@ -1642,7 +1624,7 @@ static int multipath_end_io_bio(struct dm_target *ti, struct bio *clone,
if (atomic_read(&m->nr_valid_paths) == 0 &&
!test_bit(MPATHF_QUEUE_IF_NO_PATH, &m->flags)) {
if (must_push_back_bio(m)) {
if (__must_push_back(m)) {
r = DM_ENDIO_REQUEUE;
} else {
dm_report_EIO(m);