diff options
Diffstat (limited to 'kernel/power/process.c')
| -rw-r--r-- | kernel/power/process.c | 119 |
1 files changed, 3 insertions, 116 deletions
diff --git a/kernel/power/process.c b/kernel/power/process.c index 278946aecaf..ca634019497 100644 --- a/kernel/power/process.c +++ b/kernel/power/process.c | |||
| @@ -28,121 +28,6 @@ static inline int freezeable(struct task_struct * p) | |||
| 28 | return 1; | 28 | return 1; |
| 29 | } | 29 | } |
| 30 | 30 | ||
| 31 | /* | ||
| 32 | * freezing is complete, mark current process as frozen | ||
| 33 | */ | ||
| 34 | static inline void frozen_process(void) | ||
| 35 | { | ||
| 36 | if (!unlikely(current->flags & PF_NOFREEZE)) { | ||
| 37 | current->flags |= PF_FROZEN; | ||
| 38 | wmb(); | ||
| 39 | } | ||
| 40 | clear_freeze_flag(current); | ||
| 41 | } | ||
| 42 | |||
| 43 | /* Refrigerator is place where frozen processes are stored :-). */ | ||
| 44 | void refrigerator(void) | ||
| 45 | { | ||
| 46 | /* Hmm, should we be allowed to suspend when there are realtime | ||
| 47 | processes around? */ | ||
| 48 | long save; | ||
| 49 | |||
| 50 | task_lock(current); | ||
| 51 | if (freezing(current)) { | ||
| 52 | frozen_process(); | ||
| 53 | task_unlock(current); | ||
| 54 | } else { | ||
| 55 | task_unlock(current); | ||
| 56 | return; | ||
| 57 | } | ||
| 58 | save = current->state; | ||
| 59 | pr_debug("%s entered refrigerator\n", current->comm); | ||
| 60 | |||
| 61 | spin_lock_irq(¤t->sighand->siglock); | ||
| 62 | recalc_sigpending(); /* We sent fake signal, clean it up */ | ||
| 63 | spin_unlock_irq(¤t->sighand->siglock); | ||
| 64 | |||
| 65 | for (;;) { | ||
| 66 | set_current_state(TASK_UNINTERRUPTIBLE); | ||
| 67 | if (!frozen(current)) | ||
| 68 | break; | ||
| 69 | schedule(); | ||
| 70 | } | ||
| 71 | pr_debug("%s left refrigerator\n", current->comm); | ||
| 72 | __set_current_state(save); | ||
| 73 | } | ||
| 74 | |||
| 75 | static void fake_signal_wake_up(struct task_struct *p) | ||
| 76 | { | ||
| 77 | unsigned long flags; | ||
| 78 | |||
| 79 | spin_lock_irqsave(&p->sighand->siglock, flags); | ||
| 80 | signal_wake_up(p, 0); | ||
| 81 | spin_unlock_irqrestore(&p->sighand->siglock, flags); | ||
| 82 | } | ||
| 83 | |||
| 84 | static inline bool should_send_signal(struct task_struct *p) | ||
| 85 | { | ||
| 86 | return !(p->flags & PF_FREEZER_NOSIG); | ||
| 87 | } | ||
| 88 | |||
| 89 | /** | ||
| 90 | * freeze_task - send a freeze request to given task | ||
| 91 | * @p: task to send the request to | ||
| 92 | * @sig_only: if set, the request will only be sent if the task has the | ||
| 93 | * PF_FREEZER_NOSIG flag unset | ||
| 94 | * Return value: 'false', if @sig_only is set and the task has | ||
| 95 | * PF_FREEZER_NOSIG set or the task is frozen, 'true', otherwise | ||
| 96 | * | ||
| 97 | * The freeze request is sent by setting the tasks's TIF_FREEZE flag and | ||
| 98 | * either sending a fake signal to it or waking it up, depending on whether | ||
| 99 | * or not it has PF_FREEZER_NOSIG set. If @sig_only is set and the task | ||
| 100 | * has PF_FREEZER_NOSIG set (ie. it is a typical kernel thread), its | ||
| 101 | * TIF_FREEZE flag will not be set. | ||
| 102 | */ | ||
| 103 | static bool freeze_task(struct task_struct *p, bool sig_only) | ||
| 104 | { | ||
| 105 | /* | ||
| 106 | * We first check if the task is freezing and next if it has already | ||
| 107 | * been frozen to avoid the race with frozen_process() which first marks | ||
| 108 | * the task as frozen and next clears its TIF_FREEZE. | ||
| 109 | */ | ||
| 110 | if (!freezing(p)) { | ||
| 111 | rmb(); | ||
| 112 | if (frozen(p)) | ||
| 113 | return false; | ||
| 114 | |||
| 115 | if (!sig_only || should_send_signal(p)) | ||
| 116 | set_freeze_flag(p); | ||
| 117 | else | ||
| 118 | return false; | ||
| 119 | } | ||
| 120 | |||
| 121 | if (should_send_signal(p)) { | ||
| 122 | if (!signal_pending(p)) | ||
| 123 | fake_signal_wake_up(p); | ||
| 124 | } else if (sig_only) { | ||
| 125 | return false; | ||
| 126 | } else { | ||
| 127 | wake_up_state(p, TASK_INTERRUPTIBLE); | ||
| 128 | } | ||
| 129 | |||
| 130 | return true; | ||
| 131 | } | ||
| 132 | |||
| 133 | static void cancel_freezing(struct task_struct *p) | ||
| 134 | { | ||
| 135 | unsigned long flags; | ||
| 136 | |||
| 137 | if (freezing(p)) { | ||
| 138 | pr_debug(" clean up: %s\n", p->comm); | ||
| 139 | clear_freeze_flag(p); | ||
| 140 | spin_lock_irqsave(&p->sighand->siglock, flags); | ||
| 141 | recalc_sigpending_and_wake(p); | ||
| 142 | spin_unlock_irqrestore(&p->sighand->siglock, flags); | ||
| 143 | } | ||
| 144 | } | ||
| 145 | |||
| 146 | static int try_to_freeze_tasks(bool sig_only) | 31 | static int try_to_freeze_tasks(bool sig_only) |
| 147 | { | 32 | { |
| 148 | struct task_struct *g, *p; | 33 | struct task_struct *g, *p; |
| @@ -250,6 +135,9 @@ static void thaw_tasks(bool nosig_only) | |||
| 250 | if (nosig_only && should_send_signal(p)) | 135 | if (nosig_only && should_send_signal(p)) |
| 251 | continue; | 136 | continue; |
| 252 | 137 | ||
| 138 | if (cgroup_frozen(p)) | ||
| 139 | continue; | ||
| 140 | |||
| 253 | thaw_process(p); | 141 | thaw_process(p); |
| 254 | } while_each_thread(g, p); | 142 | } while_each_thread(g, p); |
| 255 | read_unlock(&tasklist_lock); | 143 | read_unlock(&tasklist_lock); |
| @@ -264,4 +152,3 @@ void thaw_processes(void) | |||
| 264 | printk("done.\n"); | 152 | printk("done.\n"); |
| 265 | } | 153 | } |
| 266 | 154 | ||
| 267 | EXPORT_SYMBOL(refrigerator); | ||
