[PATCH] convert pm_sem to a mutex
Stephen Hemminger [Thu, 7 Dec 2006 04:34:35 +0000 (20:34 -0800)]
The power management semaphore is only used as mutex, so convert it.

[akpm@osdl.org: fix rotten bug]
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Acked-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

kernel/power/disk.c
kernel/power/main.c
kernel/power/power.h
kernel/power/user.c

index 53b3b57..08d9e7a 100644 (file)
@@ -213,10 +213,10 @@ static int software_resume(void)
 {
        int error;
 
-       down(&pm_sem);
+       mutex_lock(&pm_mutex);
        if (!swsusp_resume_device) {
                if (!strlen(resume_file)) {
-                       up(&pm_sem);
+                       mutex_unlock(&pm_mutex);
                        return -ENOENT;
                }
                swsusp_resume_device = name_to_dev_t(resume_file);
@@ -231,7 +231,7 @@ static int software_resume(void)
                 * FIXME: If noresume is specified, we need to find the partition
                 * and reset it back to normal swap space.
                 */
-               up(&pm_sem);
+               mutex_unlock(&pm_mutex);
                return 0;
        }
 
@@ -275,7 +275,7 @@ static int software_resume(void)
        unprepare_processes();
  Done:
        /* For success case, the suspend path will release the lock */
-       up(&pm_sem);
+       mutex_unlock(&pm_mutex);
        pr_debug("PM: Resume from disk failed.\n");
        return 0;
 }
@@ -336,7 +336,7 @@ static ssize_t disk_store(struct subsystem * s, const char * buf, size_t n)
        p = memchr(buf, '\n', n);
        len = p ? p - buf : n;
 
-       down(&pm_sem);
+       mutex_lock(&pm_mutex);
        for (i = PM_DISK_FIRMWARE; i < PM_DISK_MAX; i++) {
                if (!strncmp(buf, pm_disk_modes[i], len)) {
                        mode = i;
@@ -360,7 +360,7 @@ static ssize_t disk_store(struct subsystem * s, const char * buf, size_t n)
 
        pr_debug("PM: suspend-to-disk mode set to '%s'\n",
                 pm_disk_modes[mode]);
-       up(&pm_sem);
+       mutex_unlock(&pm_mutex);
        return error ? error : n;
 }
 
@@ -385,9 +385,9 @@ static ssize_t resume_store(struct subsystem *subsys, const char *buf, size_t n)
        if (maj != MAJOR(res) || min != MINOR(res))
                goto out;
 
-       down(&pm_sem);
+       mutex_lock(&pm_mutex);
        swsusp_resume_device = res;
-       up(&pm_sem);
+       mutex_unlock(&pm_mutex);
        printk("Attempting manual resume\n");
        noresume = 0;
        software_resume();
index 6096c71..751157b 100644 (file)
@@ -25,7 +25,7 @@
 /*This is just an arbitrary number */
 #define FREE_PAGE_NUMBER (100)
 
-DECLARE_MUTEX(pm_sem);
+DEFINE_MUTEX(pm_mutex);
 
 struct pm_ops *pm_ops;
 suspend_disk_method_t pm_disk_mode = PM_DISK_SHUTDOWN;
@@ -37,9 +37,9 @@ suspend_disk_method_t pm_disk_mode = PM_DISK_SHUTDOWN;
 
 void pm_set_ops(struct pm_ops * ops)
 {
-       down(&pm_sem);
+       mutex_lock(&pm_mutex);
        pm_ops = ops;
-       up(&pm_sem);
+       mutex_unlock(&pm_mutex);
 }
 
 
@@ -183,7 +183,7 @@ static int enter_state(suspend_state_t state)
 
        if (!valid_state(state))
                return -ENODEV;
-       if (down_trylock(&pm_sem))
+       if (!mutex_trylock(&pm_mutex))
                return -EBUSY;
 
        if (state == PM_SUSPEND_DISK) {
@@ -201,7 +201,7 @@ static int enter_state(suspend_state_t state)
        pr_debug("PM: Finishing wakeup.\n");
        suspend_finish(state);
  Unlock:
-       up(&pm_sem);
+       mutex_unlock(&pm_mutex);
        return error;
 }
 
index 3afa5db..eb461b8 100644 (file)
@@ -22,7 +22,9 @@ static inline int pm_suspend_disk(void)
        return -EPERM;
 }
 #endif
-extern struct semaphore pm_sem;
+
+extern struct mutex pm_mutex;
+
 #define power_attr(_name) \
 static struct subsys_attribute _name##_attr = {        \
        .attr   = {                             \
index 26c6694..905dc26 100644 (file)
@@ -79,10 +79,10 @@ static int snapshot_release(struct inode *inode, struct file *filp)
        free_all_swap_pages(data->swap, data->bitmap);
        free_bitmap(data->bitmap);
        if (data->frozen) {
-               down(&pm_sem);
+               mutex_lock(&pm_mutex);
                thaw_processes();
                enable_nonboot_cpus();
-               up(&pm_sem);
+               mutex_unlock(&pm_mutex);
        }
        atomic_inc(&device_available);
        return 0;
@@ -144,7 +144,7 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp,
        case SNAPSHOT_FREEZE:
                if (data->frozen)
                        break;
-               down(&pm_sem);
+               mutex_lock(&pm_mutex);
                error = disable_nonboot_cpus();
                if (!error) {
                        error = freeze_processes();
@@ -154,7 +154,7 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp,
                                error = -EBUSY;
                        }
                }
-               up(&pm_sem);
+               mutex_unlock(&pm_mutex);
                if (!error)
                        data->frozen = 1;
                break;
@@ -162,10 +162,10 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp,
        case SNAPSHOT_UNFREEZE:
                if (!data->frozen)
                        break;
-               down(&pm_sem);
+               mutex_lock(&pm_mutex);
                thaw_processes();
                enable_nonboot_cpus();
-               up(&pm_sem);
+               mutex_unlock(&pm_mutex);
                data->frozen = 0;
                break;
 
@@ -174,7 +174,7 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp,
                        error = -EPERM;
                        break;
                }
-               down(&pm_sem);
+               mutex_lock(&pm_mutex);
                /* Free memory before shutting down devices. */
                error = swsusp_shrink_memory();
                if (!error) {
@@ -187,7 +187,7 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp,
                        }
                        resume_console();
                }
-               up(&pm_sem);
+               mutex_unlock(&pm_mutex);
                if (!error)
                        error = put_user(in_suspend, (unsigned int __user *)arg);
                if (!error)
@@ -201,7 +201,7 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp,
                        error = -EPERM;
                        break;
                }
-               down(&pm_sem);
+               mutex_lock(&pm_mutex);
                pm_prepare_console();
                suspend_console();
                error = device_suspend(PMSG_PRETHAW);
@@ -211,7 +211,7 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp,
                }
                resume_console();
                pm_restore_console();
-               up(&pm_sem);
+               mutex_unlock(&pm_mutex);
                break;
 
        case SNAPSHOT_FREE:
@@ -286,7 +286,7 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp,
                        break;
                }
 
-               if (down_trylock(&pm_sem)) {
+               if (!mutex_trylock(&pm_mutex)) {
                        error = -EBUSY;
                        break;
                }
@@ -314,7 +314,7 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp,
                        pm_ops->finish(PM_SUSPEND_MEM);
 
 OutS3:
-               up(&pm_sem);
+               mutex_unlock(&pm_mutex);
                break;
 
        case SNAPSHOT_PMOPS: