percpu_ida: Make percpu_ida_alloc + callers accept task state bitmask

This patch changes percpu_ida_alloc() + callers to accept task state
bitmask for prepare_to_wait() for code like target/iscsi that needs
it for interruptible sleep, that is provided in a subsequent patch.

It now expects TASK_UNINTERRUPTIBLE when the caller is able to sleep
waiting for a new tag, or TASK_RUNNING when the caller cannot sleep,
and is forced to return a negative value when no tags are available.

v2 changes:
  - Include blk-mq + tcm_fc + vhost/scsi + target/iscsi changes
  - Drop signal_pending_state() call
v3 changes:
  - Only call prepare_to_wait() + finish_wait() when != TASK_RUNNING
    (PeterZ)

Reported-by: Linus Torvalds <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Jens Axboe <[email protected]>
Signed-off-by: Kent Overstreet <[email protected]>
Cc: <[email protected]> #3.12+
Signed-off-by: Nicholas Bellinger <[email protected]>
This commit is contained in:
Kent Overstreet 2014-01-19 08:26:37 +00:00 • committed by Nicholas Bellinger
commit 6f6b5d1ec5
6 changed files with 23 additions and 14 deletions

View file

@ -36,7 +36,8 @@ static unsigned int __blk_mq_get_tag(struct blk_mq_tags *tags, gfp_t gfp)
{
int tag;
tag = percpu_ida_alloc(&tags->free_tags, gfp);
tag = percpu_ida_alloc(&tags->free_tags, (gfp & __GFP_WAIT) ?
TASK_UNINTERRUPTIBLE : TASK_RUNNING);
if (tag < 0)
return BLK_MQ_TAG_FAIL;
return tag + tags->nr_reserved_tags;
@ -52,7 +53,8 @@ static unsigned int __blk_mq_get_reserved_tag(struct blk_mq_tags *tags,
return BLK_MQ_TAG_FAIL;
}
tag = percpu_ida_alloc(&tags->reserved_tags, gfp);
tag = percpu_ida_alloc(&tags->reserved_tags, (gfp & __GFP_WAIT) ?
TASK_UNINTERRUPTIBLE : TASK_RUNNING);
if (tag < 0)
return BLK_MQ_TAG_FAIL;
return tag;