freezer: introduce freezer-friendly waiting macros

e42837bc · Rafael J. Wysocki <[email protected]> · 2007-10-18 03:04:45 -07:00

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 <[email protected]>
Acked-by: Pavel Machek <[email protected]>
Cc: Nigel Cunningham <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

Commit: e42837bcd35b75bb59ae5d3e62f87be1aeeb05c3
Parents: 2e131895

Changes

7 files changed · +45 −13

File	Status	Add	Del	Content
drivers/input/gameport/gameport.c	modified	+1	−2	View file
drivers/input/serio/serio.c	modified	+1	−2	View file
drivers/input/touchscreen/ucb1400_ts.c	modified	+1	−2	View file
drivers/media/dvb/dvb-core/dvb_frontend.c	modified	+2	−1	View file
drivers/usb/core/hub.c	modified	+1	−2	View file
drivers/usb/storage/usb.c	modified	+1	−4	View file
include/linux/freezer.h	modified	+38	−0	View file

drivers/input/gameport/gameport.c

View file

diff --git a/drivers/input/gameport/gameport.c b/drivers/input/gameport/gameport.c
index 20896d5..ec1b6cf 100644
--- a/drivers/input/gameport/gameport.c
+++ b/drivers/input/gameport/gameport.c
@@ -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");

drivers/input/serio/serio.c

View file

diff --git a/drivers/input/serio/serio.c b/drivers/input/serio/serio.c
index b3bc15a..7f52938 100644
--- a/drivers/input/serio/serio.c
+++ b/drivers/input/serio/serio.c
@@ -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");

drivers/input/touchscreen/ucb1400_ts.c

View file

diff --git a/drivers/input/touchscreen/ucb1400_ts.c b/drivers/input/touchscreen/ucb1400_ts.c
index 86aed64..89373b0 100644
--- a/drivers/input/touchscreen/ucb1400_ts.c
+++ b/drivers/input/touchscreen/ucb1400_ts.c
@@ -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 */

drivers/media/dvb/dvb-core/dvb_frontend.c

View file

diff --git a/drivers/media/dvb/dvb-core/dvb_frontend.c b/drivers/media/dvb/dvb-core/dvb_frontend.c
index b203640..445f026 100644
--- a/drivers/media/dvb/dvb-core/dvb_frontend.c
+++ b/drivers/media/dvb/dvb-core/dvb_frontend.c
@@ -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)) {

drivers/usb/core/hub.c

View file

diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index 60a8f55..036c3de 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -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);

drivers/usb/storage/usb.c

View file

diff --git a/drivers/usb/storage/usb.c b/drivers/usb/storage/usb.c
index 3451e8d..ac6114e 100644
--- a/drivers/usb/storage/usb.c
+++ b/drivers/usb/storage/usb.c
@@ -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 */

include/linux/freezer.h

View file

diff --git a/include/linux/freezer.h b/include/linux/freezer.h
index efded00..0893499 100644
--- a/include/linux/freezer.h
+++ b/include/linux/freezer.h
@@ -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 */