diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /kernel/power/process.c |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'kernel/power/process.c')
-rw-r--r-- | kernel/power/process.c | 121 |
1 files changed, 121 insertions, 0 deletions
diff --git a/kernel/power/process.c b/kernel/power/process.c new file mode 100644 index 000000000000..78d92dc6a1ed --- /dev/null +++ b/kernel/power/process.c | |||
@@ -0,0 +1,121 @@ | |||
1 | /* | ||
2 | * drivers/power/process.c - Functions for starting/stopping processes on | ||
3 | * suspend transitions. | ||
4 | * | ||
5 | * Originally from swsusp. | ||
6 | */ | ||
7 | |||
8 | |||
9 | #undef DEBUG | ||
10 | |||
11 | #include <linux/smp_lock.h> | ||
12 | #include <linux/interrupt.h> | ||
13 | #include <linux/suspend.h> | ||
14 | #include <linux/module.h> | ||
15 | |||
16 | /* | ||
17 | * Timeout for stopping processes | ||
18 | */ | ||
19 | #define TIMEOUT (6 * HZ) | ||
20 | |||
21 | |||
22 | static inline int freezeable(struct task_struct * p) | ||
23 | { | ||
24 | if ((p == current) || | ||
25 | (p->flags & PF_NOFREEZE) || | ||
26 | (p->exit_state == EXIT_ZOMBIE) || | ||
27 | (p->exit_state == EXIT_DEAD) || | ||
28 | (p->state == TASK_STOPPED) || | ||
29 | (p->state == TASK_TRACED)) | ||
30 | return 0; | ||
31 | return 1; | ||
32 | } | ||
33 | |||
34 | /* Refrigerator is place where frozen processes are stored :-). */ | ||
35 | void refrigerator(unsigned long flag) | ||
36 | { | ||
37 | /* Hmm, should we be allowed to suspend when there are realtime | ||
38 | processes around? */ | ||
39 | long save; | ||
40 | save = current->state; | ||
41 | current->state = TASK_UNINTERRUPTIBLE; | ||
42 | pr_debug("%s entered refrigerator\n", current->comm); | ||
43 | printk("="); | ||
44 | current->flags &= ~PF_FREEZE; | ||
45 | |||
46 | spin_lock_irq(¤t->sighand->siglock); | ||
47 | recalc_sigpending(); /* We sent fake signal, clean it up */ | ||
48 | spin_unlock_irq(¤t->sighand->siglock); | ||
49 | |||
50 | current->flags |= PF_FROZEN; | ||
51 | while (current->flags & PF_FROZEN) | ||
52 | schedule(); | ||
53 | pr_debug("%s left refrigerator\n", current->comm); | ||
54 | current->state = save; | ||
55 | } | ||
56 | |||
57 | /* 0 = success, else # of processes that we failed to stop */ | ||
58 | int freeze_processes(void) | ||
59 | { | ||
60 | int todo; | ||
61 | unsigned long start_time; | ||
62 | struct task_struct *g, *p; | ||
63 | |||
64 | printk( "Stopping tasks: " ); | ||
65 | start_time = jiffies; | ||
66 | do { | ||
67 | todo = 0; | ||
68 | read_lock(&tasklist_lock); | ||
69 | do_each_thread(g, p) { | ||
70 | unsigned long flags; | ||
71 | if (!freezeable(p)) | ||
72 | continue; | ||
73 | if ((p->flags & PF_FROZEN) || | ||
74 | (p->state == TASK_TRACED) || | ||
75 | (p->state == TASK_STOPPED)) | ||
76 | continue; | ||
77 | |||
78 | /* FIXME: smp problem here: we may not access other process' flags | ||
79 | without locking */ | ||
80 | p->flags |= PF_FREEZE; | ||
81 | spin_lock_irqsave(&p->sighand->siglock, flags); | ||
82 | signal_wake_up(p, 0); | ||
83 | spin_unlock_irqrestore(&p->sighand->siglock, flags); | ||
84 | todo++; | ||
85 | } while_each_thread(g, p); | ||
86 | read_unlock(&tasklist_lock); | ||
87 | yield(); /* Yield is okay here */ | ||
88 | if (time_after(jiffies, start_time + TIMEOUT)) { | ||
89 | printk( "\n" ); | ||
90 | printk(KERN_ERR " stopping tasks failed (%d tasks remaining)\n", todo ); | ||
91 | return todo; | ||
92 | } | ||
93 | } while(todo); | ||
94 | |||
95 | printk( "|\n" ); | ||
96 | BUG_ON(in_atomic()); | ||
97 | return 0; | ||
98 | } | ||
99 | |||
100 | void thaw_processes(void) | ||
101 | { | ||
102 | struct task_struct *g, *p; | ||
103 | |||
104 | printk( "Restarting tasks..." ); | ||
105 | read_lock(&tasklist_lock); | ||
106 | do_each_thread(g, p) { | ||
107 | if (!freezeable(p)) | ||
108 | continue; | ||
109 | if (p->flags & PF_FROZEN) { | ||
110 | p->flags &= ~PF_FROZEN; | ||
111 | wake_up_process(p); | ||
112 | } else | ||
113 | printk(KERN_INFO " Strange, %s not stopped\n", p->comm ); | ||
114 | } while_each_thread(g, p); | ||
115 | |||
116 | read_unlock(&tasklist_lock); | ||
117 | schedule(); | ||
118 | printk( " done\n" ); | ||
119 | } | ||
120 | |||
121 | EXPORT_SYMBOL(refrigerator); | ||