freezer: introduce freezer-friendly waiting macros

Introduce freezer-friendly wrappers around wait_event_interruptible() and
wait_event_interruptible_timeout(), originally defined in <linux/wait.h>, to
be used in freezable kernel threads.  Make some of the freezable kernel
threads use them.

This is necessary for the freezer to stop sending signals to kernel threads,
which is implemented in the next patch.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: Nigel Cunningham <nigel@nigel.suspend2.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Rafael J. Wysocki 2007-10-18 03:04:45 -07:00 committed by Linus Torvalds
parent 2e1318956c
commit e42837bcd3
7 changed files with 45 additions and 13 deletions

View File

@ -448,9 +448,8 @@ static int gameport_thread(void *nothing)
set_freezable();
do {
gameport_handle_event();
wait_event_interruptible(gameport_wait,
wait_event_freezable(gameport_wait,
kthread_should_stop() || !list_empty(&gameport_event_list));
try_to_freeze();
} while (!kthread_should_stop());
printk(KERN_DEBUG "gameport: kgameportd exiting\n");

View File

@ -387,9 +387,8 @@ static int serio_thread(void *nothing)
set_freezable();
do {
serio_handle_event();
wait_event_interruptible(serio_wait,
wait_event_freezable(serio_wait,
kthread_should_stop() || !list_empty(&serio_event_list));
try_to_freeze();
} while (!kthread_should_stop());
printk(KERN_DEBUG "serio: kseriod exiting\n");

View File

@ -333,10 +333,9 @@ static int ucb1400_ts_thread(void *_ucb)
timeout = msecs_to_jiffies(10);
}
wait_event_interruptible_timeout(ucb->ts_wait,
wait_event_freezable_timeout(ucb->ts_wait,
ucb->irq_pending || ucb->ts_restart || kthread_should_stop(),
timeout);
try_to_freeze();
}
/* Send the "pen off" if we are stopping with the pen still active */

View File

@ -527,7 +527,8 @@ static int dvb_frontend_thread(void *data)
up(&fepriv->sem); /* is locked when we enter the thread... */
restart:
timeout = wait_event_interruptible_timeout(fepriv->wait_queue,
dvb_frontend_should_wakeup(fe) || kthread_should_stop(),
dvb_frontend_should_wakeup(fe) || kthread_should_stop()
|| freezing(current),
fepriv->delay);
if (kthread_should_stop() || dvb_frontend_is_exiting(fe)) {

View File

@ -2870,10 +2870,9 @@ static int hub_thread(void *__unused)
set_freezable();
do {
hub_events();
wait_event_interruptible(khubd_wait,
wait_event_freezable(khubd_wait,
!list_empty(&hub_event_list) ||
kthread_should_stop());
try_to_freeze();
} while (!kthread_should_stop() || !list_empty(&hub_event_list));
pr_debug("%s: khubd exiting\n", usbcore_name);

View File

@ -907,12 +907,9 @@ static int usb_stor_scan_thread(void * __us)
if (delay_use > 0) {
printk(KERN_DEBUG "usb-storage: waiting for device "
"to settle before scanning\n");
retry:
wait_event_interruptible_timeout(us->delay_wait,
wait_event_freezable_timeout(us->delay_wait,
test_bit(US_FLIDX_DISCONNECTING, &us->flags),
delay_use * HZ);
if (try_to_freeze())
goto retry;
}
/* If the device is still connected, perform the scanning */

View File

@ -4,6 +4,7 @@
#define FREEZER_H_INCLUDED
#include <linux/sched.h>
#include <linux/wait.h>
#ifdef CONFIG_PM_SLEEP
/*
@ -126,6 +127,36 @@ static inline void set_freezable(void)
current->flags &= ~PF_NOFREEZE;
}
/*
* Freezer-friendly wrappers around wait_event_interruptible() and
* wait_event_interruptible_timeout(), originally defined in <linux/wait.h>
*/
#define wait_event_freezable(wq, condition) \
({ \
int __retval; \
do { \
__retval = wait_event_interruptible(wq, \
(condition) || freezing(current)); \
if (__retval && !freezing(current)) \
break; \
else if (!(condition)) \
__retval = -ERESTARTSYS; \
} while (try_to_freeze()); \
__retval; \
})
#define wait_event_freezable_timeout(wq, condition, timeout) \
({ \
long __retval = timeout; \
do { \
__retval = wait_event_interruptible_timeout(wq, \
(condition) || freezing(current), \
__retval); \
} while (try_to_freeze()); \
__retval; \
})
#else /* !CONFIG_PM_SLEEP */
static inline int frozen(struct task_struct *p) { return 0; }
static inline int freezing(struct task_struct *p) { return 0; }
@ -143,6 +174,13 @@ static inline void freezer_do_not_count(void) {}
static inline void freezer_count(void) {}
static inline int freezer_should_skip(struct task_struct *p) { return 0; }
static inline void set_freezable(void) {}
#define wait_event_freezable(wq, condition) \
wait_event_interruptible(wq, condition)
#define wait_event_freezable_timeout(wq, condition, timeout) \
wait_event_interruptible_timeout(wq, condition, timeout)
#endif /* !CONFIG_PM_SLEEP */
#endif /* FREEZER_H_INCLUDED */