diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2009-10-14 09:20:41 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2009-10-14 15:14:31 -0700 |
| commit | 97ad5a034dcc164269d0b8a5cb3e827b33455c11 (patch) | |
| tree | a6bb960fbfeb3579212cd066138f7d159cf66760 | |
| parent | 8c53e46314562fe814b0afef6cfcbd2f562b017c (diff) | |
tty: use the new 'flush_delayed_work()' helper to do ldisc flush
This way all flush_to_ldisc work is always done through the workqueues,
and we thus have a single point of serialization. It also means that we
can avoid calling flush_to_ldisc() entirely if there was no delayed work
pending.
[ Side note: using workqueues and keventd as the single way to enter
flush_to_ldisc() still doesn't absolutely guarantee that we can't have
concurrency: keventd is multithreaded and has a thread per CPU, and
while the WORK_STRUCT_PENDING bit guarantees a single work only being
on the pending list once, the work might be both pending and _running_
at the same time. Workqueues are not simple. ]
This was also confirmed to fix bugzilla #14388, even without the earlier
locking fix and cleanup (commit c8e331419: "tty: Make flush_to_ldisc()
locking more robust"). So both commits fix the same bug differently,
and either would have worked on its own. But I'm committing them both
since they are cleanups independent of each other.
Reported-and-tested-by: Boyan <btanastasov@yahoo.co.uk>
Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | drivers/char/tty_buffer.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/char/tty_buffer.c b/drivers/char/tty_buffer.c index 0296612cc7d..66fa4e10d76 100644 --- a/drivers/char/tty_buffer.c +++ b/drivers/char/tty_buffer.c @@ -468,7 +468,7 @@ static void flush_to_ldisc(struct work_struct *work) */ void tty_flush_to_ldisc(struct tty_struct *tty) { - flush_to_ldisc(&tty->buf.work.work); + flush_delayed_work(&tty->buf.work); } /** |