[PATCH] swsusp: Untangle thaw_processes

Move the loop from thaw_processes() to a separate function and call it
independently for kernel threads and user space processes so that the order
of thawing tasks is clearly visible.

Drop thaw_kernel_threads() which is never used.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Nigel Cunningham <nigel@suspend2.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Rafael J. Wysocki 2006-12-06 20:34:37 -08:00 committed by Linus Torvalds
parent a6d7098060
commit a9b6f562f1
2 changed files with 28 additions and 27 deletions

View File

@ -1,8 +1,5 @@
/* Freezer declarations */
#define FREEZER_KERNEL_THREADS 0
#define FREEZER_ALL_THREADS 1
#ifdef CONFIG_PM
/*
* Check if a process has been frozen
@ -60,8 +57,7 @@ static inline void frozen_process(struct task_struct *p)
extern void refrigerator(void);
extern int freeze_processes(void);
#define thaw_processes() do { thaw_some_processes(FREEZER_ALL_THREADS); } while(0)
#define thaw_kernel_threads() do { thaw_some_processes(FREEZER_KERNEL_THREADS); } while(0)
extern void thaw_processes(void);
static inline int try_to_freeze(void)
{

View File

@ -20,6 +20,8 @@
*/
#define TIMEOUT (20 * HZ)
#define FREEZER_KERNEL_THREADS 0
#define FREEZER_USER_SPACE 1
static inline int freezeable(struct task_struct * p)
{
@ -79,6 +81,11 @@ static void cancel_freezing(struct task_struct *p)
}
}
static inline int is_user_space(struct task_struct *p)
{
return p->mm && !(p->flags & PF_BORROWED_MM);
}
/* 0 = success, else # of processes that we failed to stop */
int freeze_processes(void)
{
@ -103,10 +110,9 @@ int freeze_processes(void)
cancel_freezing(p);
continue;
}
if (p->mm && !(p->flags & PF_BORROWED_MM)) {
/* The task is a user-space one.
* Freeze it unless there's a vfork completion
* pending
if (is_user_space(p)) {
/* Freeze the task unless there is a vfork
* completion pending
*/
if (!p->vfork_done)
freeze_process(p);
@ -155,31 +161,30 @@ int freeze_processes(void)
return 0;
}
void thaw_some_processes(int all)
static void thaw_tasks(int thaw_user_space)
{
struct task_struct *g, *p;
int pass = 0; /* Pass 0 = Kernel space, 1 = Userspace */
printk("Restarting tasks... ");
read_lock(&tasklist_lock);
do {
do_each_thread(g, p) {
/*
* is_user = 0 if kernel thread or borrowed mm,
* 1 otherwise.
*/
int is_user = !!(p->mm && !(p->flags & PF_BORROWED_MM));
if (!freezeable(p) || (is_user != pass))
continue;
if (!thaw_process(p))
printk(KERN_INFO
"Strange, %s not stopped\n", p->comm);
} while_each_thread(g, p);
do_each_thread(g, p) {
if (!freezeable(p))
continue;
pass++;
} while (pass < 2 && all);
if (is_user_space(p) == !thaw_user_space)
continue;
if (!thaw_process(p))
printk(KERN_WARNING " Strange, %s not stopped\n",
p->comm );
} while_each_thread(g, p);
read_unlock(&tasklist_lock);
}
void thaw_processes(void)
{
printk("Restarting tasks ... ");
thaw_tasks(FREEZER_KERNEL_THREADS);
thaw_tasks(FREEZER_USER_SPACE);
schedule();
printk("done.\n");
}