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author | Tejun Heo <tj@kernel.org> | 2008-10-15 22:01:38 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2008-10-16 11:21:31 -0700 |
commit | a25d644fc0e232f242d1f3baa63c149c42536ff0 (patch) | |
tree | c5013caca7978d862f8ea1996c5933495fd7334a /include/linux/wait.h | |
parent | c80cfb0406c01bb5da91bfe30f5cb1fd96831138 (diff) | |
download | linux-3.10-a25d644fc0e232f242d1f3baa63c149c42536ff0.tar.gz linux-3.10-a25d644fc0e232f242d1f3baa63c149c42536ff0.tar.bz2 linux-3.10-a25d644fc0e232f242d1f3baa63c149c42536ff0.zip |
wait: kill is_sync_wait()
is_sync_wait() is used to distinguish between sync and async waits.
Basically sync waits are the ones initialized with init_waitqueue_entry()
and async ones with init_waitqueue_func_entry(). The sync/async
distinction is used only in prepare_to_wait[_exclusive]() and its only
function is to skip setting the current task state if the wait is async.
This has a few problems.
* No one uses it. None of func_entry users use prepare_to_wait()
functions, so the code path never gets executed.
* The distinction is bogus. Maybe back when func_entry is used only
by aio but it's now also used by epoll and in future possibly by 9p
and poll/select.
* Taking @state as argument and ignoring it silenly depending on how
@wait is initialized is just a bad error-prone API.
* It prevents func_entry waits from using wait->private for no good
reason.
This patch kills is_sync_wait() and the associated code paths from
prepare_to_wait[_exclusive](). As there was no user of these code paths,
this patch doesn't cause any behavior difference.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include/linux/wait.h')
-rw-r--r-- | include/linux/wait.h | 9 |
1 files changed, 0 insertions, 9 deletions
diff --git a/include/linux/wait.h b/include/linux/wait.h index 0081147a9fe..ef609f842fa 100644 --- a/include/linux/wait.h +++ b/include/linux/wait.h @@ -108,15 +108,6 @@ static inline int waitqueue_active(wait_queue_head_t *q) return !list_empty(&q->task_list); } -/* - * Used to distinguish between sync and async io wait context: - * sync i/o typically specifies a NULL wait queue entry or a wait - * queue entry bound to a task (current task) to wake up. - * aio specifies a wait queue entry with an async notification - * callback routine, not associated with any task. - */ -#define is_sync_wait(wait) (!(wait) || ((wait)->private)) - extern void add_wait_queue(wait_queue_head_t *q, wait_queue_t *wait); extern void add_wait_queue_exclusive(wait_queue_head_t *q, wait_queue_t *wait); extern void remove_wait_queue(wait_queue_head_t *q, wait_queue_t *wait); |