diff --git a/include/linux/freezer.h b/include/linux/freezer.h index ba4f512d2938..93f411a52872 100644 --- a/include/linux/freezer.h +++ b/include/linux/freezer.h @@ -61,7 +61,6 @@ static inline bool try_to_freeze(void) } extern bool freeze_task(struct task_struct *p, bool sig_only); -extern void cancel_freezing(struct task_struct *p); #ifdef CONFIG_CGROUP_FREEZER extern int cgroup_freezing_or_frozen(struct task_struct *task); diff --git a/kernel/freezer.c b/kernel/freezer.c index b8b562124ba9..11e32d419dec 100644 --- a/kernel/freezer.c +++ b/kernel/freezer.c @@ -129,21 +129,6 @@ out_unlock: return ret; } -void cancel_freezing(struct task_struct *p) -{ - unsigned long flags; - - spin_lock_irqsave(&freezer_lock, flags); - if (freezing(p)) { - pr_debug(" clean up: %s\n", p->comm); - clear_freeze_flag(p); - spin_lock(&p->sighand->siglock); - recalc_sigpending_and_wake(p); - spin_unlock(&p->sighand->siglock); - } - spin_unlock_irqrestore(&freezer_lock, flags); -} - void __thaw_task(struct task_struct *p) { unsigned long flags; @@ -153,10 +138,18 @@ void __thaw_task(struct task_struct *p) * be visible to @p as waking up implies wmb. Waking up inside * freezer_lock also prevents wakeups from leaking outside * refrigerator. + * + * If !FROZEN, @p hasn't reached refrigerator, recalc sigpending to + * avoid leaving dangling TIF_SIGPENDING behind. */ spin_lock_irqsave(&freezer_lock, flags); clear_freeze_flag(p); - if (frozen(p)) + if (frozen(p)) { wake_up_process(p); + } else { + spin_lock(&p->sighand->siglock); + recalc_sigpending_and_wake(p); + spin_unlock(&p->sighand->siglock); + } spin_unlock_irqrestore(&freezer_lock, flags); } diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c index 196c01268ebd..ba2319ffc860 100644 --- a/kernel/power/hibernate.c +++ b/kernel/power/hibernate.c @@ -607,17 +607,6 @@ static void power_down(void) while(1); } -static int prepare_processes(void) -{ - int error = 0; - - if (freeze_processes()) { - error = -EBUSY; - thaw_processes(); - } - return error; -} - /** * hibernate - Carry out system hibernation, including saving the image. */ @@ -650,7 +639,7 @@ int hibernate(void) sys_sync(); printk("done.\n"); - error = prepare_processes(); + error = freeze_processes(); if (error) goto Finish; @@ -811,7 +800,7 @@ static int software_resume(void) goto close_finish; pr_debug("PM: Preparing processes for restore.\n"); - error = prepare_processes(); + error = freeze_processes(); if (error) { swsusp_close(FMODE_READ); goto Done; diff --git a/kernel/power/process.c b/kernel/power/process.c index e59676f5811d..ce643838a00c 100644 --- a/kernel/power/process.c +++ b/kernel/power/process.c @@ -91,11 +91,6 @@ static int try_to_freeze_tasks(bool sig_only) elapsed_csecs = elapsed_csecs64; if (todo) { - /* This does not unfreeze processes that are already frozen - * (we have slightly ugly calling convention in that respect, - * and caller must call thaw_processes() if something fails), - * but it cleans up leftover PF_FREEZE requests. - */ printk("\n"); printk(KERN_ERR "Freezing of tasks %s after %d.%02d seconds " "(%d tasks refusing to freeze, wq_busy=%d):\n", @@ -103,14 +98,11 @@ static int try_to_freeze_tasks(bool sig_only) elapsed_csecs / 100, elapsed_csecs % 100, todo - wq_busy, wq_busy); - thaw_workqueues(); - read_lock(&tasklist_lock); do_each_thread(g, p) { if (!wakeup && !freezer_should_skip(p) && freezing(p) && !frozen(p)) sched_show_task(p); - cancel_freezing(p); } while_each_thread(g, p); read_unlock(&tasklist_lock); } else { @@ -123,6 +115,8 @@ static int try_to_freeze_tasks(bool sig_only) /** * freeze_processes - Signal user space processes to enter the refrigerator. + * + * On success, returns 0. On failure, -errno and system is fully thawed. */ int freeze_processes(void) { @@ -137,11 +131,15 @@ int freeze_processes(void) printk("\n"); BUG_ON(in_atomic()); + if (error) + thaw_processes(); return error; } /** * freeze_kernel_threads - Make freezable kernel threads go to the refrigerator. + * + * On success, returns 0. On failure, -errno and system is fully thawed. */ int freeze_kernel_threads(void) { @@ -155,6 +153,8 @@ int freeze_kernel_threads(void) printk("\n"); BUG_ON(in_atomic()); + if (error) + thaw_processes(); return error; } diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c index 4953dc054c53..d336b27d1104 100644 --- a/kernel/power/suspend.c +++ b/kernel/power/suspend.c @@ -106,13 +106,11 @@ static int suspend_prepare(void) goto Finish; error = suspend_freeze_processes(); - if (error) { - suspend_stats.failed_freeze++; - dpm_save_failed_step(SUSPEND_FREEZE); - } else + if (!error) return 0; - suspend_thaw_processes(); + suspend_stats.failed_freeze++; + dpm_save_failed_step(SUSPEND_FREEZE); usermodehelper_enable(); Finish: pm_notifier_call_chain(PM_POST_SUSPEND); diff --git a/kernel/power/user.c b/kernel/power/user.c index 6d8f535c2b88..7cc3f5bc5c24 100644 --- a/kernel/power/user.c +++ b/kernel/power/user.c @@ -257,10 +257,8 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd, break; error = freeze_processes(); - if (error) { - thaw_processes(); + if (error) usermodehelper_enable(); - } if (!error) data->frozen = 1; break;