* [PATCH] tty: replace mutex_lock() with tty_write_lock()
@ 2013-11-21 19:12 Andreas Platschek
2013-11-22 8:09 ` walter harms
2013-11-22 8:25 ` Dan Carpenter
0 siblings, 2 replies; 5+ messages in thread
From: Andreas Platschek @ 2013-11-21 19:12 UTC (permalink / raw)
To: gregkh; +Cc: jslaby, linux-kernel, kernel-janitors, Andreas Platschek
Use tty_write_lock()/tty_write_unlock() consistently.
This takes care of the following sparse warning:
drivers/tty/tty_io.c:1169:17: warning: context imbalance in 'tty_write_message' - unexpected unlock
Signed-off-by: Andreas Platschek <andi.platschek@gmail.com>
---
drivers/tty/tty_io.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c
index 3a1a01a..13dca92 100644
--- a/drivers/tty/tty_io.c
+++ b/drivers/tty/tty_io.c
@@ -1165,7 +1165,7 @@ out:
void tty_write_message(struct tty_struct *tty, char *msg)
{
if (tty) {
- mutex_lock(&tty->atomic_write_lock);
+ tty_write_lock(tty,0);
tty_lock(tty);
if (tty->ops->write && !test_bit(TTY_CLOSING, &tty->flags)) {
tty_unlock(tty);
--
1.7.10.4
^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: [PATCH] tty: replace mutex_lock() with tty_write_lock()
2013-11-21 19:12 [PATCH] tty: replace mutex_lock() with tty_write_lock() Andreas Platschek
@ 2013-11-22 8:09 ` walter harms
2013-11-22 8:22 ` Andreas Platschek
2013-11-22 8:29 ` Dan Carpenter
2013-11-22 8:25 ` Dan Carpenter
1 sibling, 2 replies; 5+ messages in thread
From: walter harms @ 2013-11-22 8:09 UTC (permalink / raw)
To: Andreas Platschek; +Cc: gregkh, jslaby, linux-kernel, kernel-janitors
Am 21.11.2013 20:12, schrieb Andreas Platschek:
> Use tty_write_lock()/tty_write_unlock() consistently.
>
> This takes care of the following sparse warning:
> drivers/tty/tty_io.c:1169:17: warning: context imbalance in 'tty_write_message' - unexpected unlock
>
> Signed-off-by: Andreas Platschek <andi.platschek@gmail.com>
> ---
> drivers/tty/tty_io.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c
> index 3a1a01a..13dca92 100644
> --- a/drivers/tty/tty_io.c
> +++ b/drivers/tty/tty_io.c
> @@ -1165,7 +1165,7 @@ out:
> void tty_write_message(struct tty_struct *tty, char *msg)
> {
> if (tty) {
> - mutex_lock(&tty->atomic_write_lock);
> + tty_write_lock(tty,0);
> tty_lock(tty);
> if (tty->ops->write && !test_bit(TTY_CLOSING, &tty->flags)) {
> tty_unlock(tty);
i am not an expert on this but you may need to replace that tty_unlock() with tty_write_unlock().
re,
wh
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH] tty: replace mutex_lock() with tty_write_lock()
2013-11-22 8:09 ` walter harms
@ 2013-11-22 8:22 ` Andreas Platschek
2013-11-22 8:29 ` Dan Carpenter
1 sibling, 0 replies; 5+ messages in thread
From: Andreas Platschek @ 2013-11-22 8:22 UTC (permalink / raw)
To: wharms; +Cc: gregkh, jslaby, linux-kernel, kernel-janitors
Hi,
On 11/22/2013 09:09 AM, walter harms wrote:
>
> Am 21.11.2013 20:12, schrieb Andreas Platschek:
>> Use tty_write_lock()/tty_write_unlock() consistently.
>>
>> This takes care of the following sparse warning:
>> drivers/tty/tty_io.c:1169:17: warning: context imbalance in 'tty_write_message' - unexpected unlock
>>
>> Signed-off-by: Andreas Platschek <andi.platschek@gmail.com>
>> ---
>> drivers/tty/tty_io.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c
>> index 3a1a01a..13dca92 100644
>> --- a/drivers/tty/tty_io.c
>> +++ b/drivers/tty/tty_io.c
>> @@ -1165,7 +1165,7 @@ out:
>> void tty_write_message(struct tty_struct *tty, char *msg)
>> {
>> if (tty) {
>> - mutex_lock(&tty->atomic_write_lock);
>> + tty_write_lock(tty,0);
>> tty_lock(tty);
>> if (tty->ops->write && !test_bit(TTY_CLOSING, &tty->flags)) {
>> tty_unlock(tty);
> i am not an expert on this but you may need to replace that tty_unlock() with tty_write_unlock()
The tty_unlock() you see in the patch belongs to the tty_lock() right
after the tty_write_lock(), the tty_write_unlock() is already in place
without my patch.
tty_lock()/tty_unlock() and tty_write_lock()/tty_write_unlock() are
operating on different mutexes, both are needed here.
thx!
Andi
>
> re,
> wh
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH] tty: replace mutex_lock() with tty_write_lock()
2013-11-21 19:12 [PATCH] tty: replace mutex_lock() with tty_write_lock() Andreas Platschek
2013-11-22 8:09 ` walter harms
@ 2013-11-22 8:25 ` Dan Carpenter
1 sibling, 0 replies; 5+ messages in thread
From: Dan Carpenter @ 2013-11-22 8:25 UTC (permalink / raw)
To: Andreas Platschek; +Cc: gregkh, jslaby, linux-kernel, kernel-janitors
On Thu, Nov 21, 2013 at 08:12:12PM +0100, Andreas Platschek wrote:
> Use tty_write_lock()/tty_write_unlock() consistently.
>
> This takes care of the following sparse warning:
> drivers/tty/tty_io.c:1169:17: warning: context imbalance in 'tty_write_message' - unexpected unlock
>
I don't think we can do this. mutex_lock() always succeeds and
tty_write_lock() can fail.
I think we just have to live with the error message.
regards,
dan carpenter
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH] tty: replace mutex_lock() with tty_write_lock()
2013-11-22 8:09 ` walter harms
2013-11-22 8:22 ` Andreas Platschek
@ 2013-11-22 8:29 ` Dan Carpenter
1 sibling, 0 replies; 5+ messages in thread
From: Dan Carpenter @ 2013-11-22 8:29 UTC (permalink / raw)
To: walter harms
Cc: Andreas Platschek, gregkh, jslaby, linux-kernel, kernel-janitors
On Fri, Nov 22, 2013 at 09:09:15AM +0100, walter harms wrote:
>
>
> Am 21.11.2013 20:12, schrieb Andreas Platschek:
> > Use tty_write_lock()/tty_write_unlock() consistently.
> >
> > This takes care of the following sparse warning:
> > drivers/tty/tty_io.c:1169:17: warning: context imbalance in 'tty_write_message' - unexpected unlock
> >
> > Signed-off-by: Andreas Platschek <andi.platschek@gmail.com>
> > ---
> > drivers/tty/tty_io.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c
> > index 3a1a01a..13dca92 100644
> > --- a/drivers/tty/tty_io.c
> > +++ b/drivers/tty/tty_io.c
> > @@ -1165,7 +1165,7 @@ out:
> > void tty_write_message(struct tty_struct *tty, char *msg)
> > {
> > if (tty) {
> > - mutex_lock(&tty->atomic_write_lock);
> > + tty_write_lock(tty,0);
> > tty_lock(tty);
> > if (tty->ops->write && !test_bit(TTY_CLOSING, &tty->flags)) {
> > tty_unlock(tty);
>
> i am not an expert on this but you may need to replace that tty_unlock() with tty_write_unlock().
No. The original code is correct.
regards,
dan carpenter
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2013-11-22 8:29 UTC | newest]
Thread overview: 5+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2013-11-21 19:12 [PATCH] tty: replace mutex_lock() with tty_write_lock() Andreas Platschek
2013-11-22 8:09 ` walter harms
2013-11-22 8:22 ` Andreas Platschek
2013-11-22 8:29 ` Dan Carpenter
2013-11-22 8:25 ` Dan Carpenter
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox