From 03afed8bc296fa70186ba832c1126228bb992465 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Mon, 21 Nov 2011 12:32:24 -0800 Subject: freezer: clean up freeze_processes() failure path freeze_processes() failure path is rather messy. Freezing is canceled for workqueues and tasks which aren't frozen yet but frozen tasks are left alone and should be thawed by the caller and of course some callers (xen and kexec) didn't do it. This patch updates __thaw_task() to handle cancelation correctly and makes freeze_processes() and freeze_kernel_threads() call thaw_processes() on failure instead so that the system is fully thawed on failure. Unnecessary [suspend_]thaw_processes() calls are removed from kernel/power/hibernate.c, suspend.c and user.c. While at it, restructure error checking if clause in suspend_prepare() to be less weird. -v2: Srivatsa spotted missing removal of suspend_thaw_processes() in suspend_prepare() and error in commit message. Updated. Signed-off-by: Tejun Heo Acked-by: Srivatsa S. Bhat --- kernel/power/hibernate.c | 15 ++------------- 1 file changed, 2 insertions(+), 13 deletions(-) (limited to 'kernel/power/hibernate.c') 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; -- cgit v1.2.1 From 953a206393b1533ceb0e7d725cc5a8c8d7ed97dd Mon Sep 17 00:00:00 2001 From: "Srivatsa S. Bhat" Date: Tue, 22 Nov 2011 23:20:31 +0100 Subject: PM / Hibernate: Refactor and simplify hibernation_snapshot() code The goto statements in hibernation_snapshot() are a bit complex. Refactor the code to remove some of them, thereby simplifying the implementation. Signed-off-by: Srivatsa S. Bhat Signed-off-by: Rafael J. Wysocki --- kernel/power/hibernate.c | 22 +++++++++------------- 1 file changed, 9 insertions(+), 13 deletions(-) (limited to 'kernel/power/hibernate.c') diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c index a6b0503574ee..ebf62c3bc9f7 100644 --- a/kernel/power/hibernate.c +++ b/kernel/power/hibernate.c @@ -333,7 +333,7 @@ static int create_image(int platform_mode) */ int hibernation_snapshot(int platform_mode) { - pm_message_t msg = PMSG_RECOVER; + pm_message_t msg; int error; error = platform_begin(platform_mode); @@ -362,26 +362,26 @@ int hibernation_snapshot(int platform_mode) error = dpm_prepare(PMSG_FREEZE); if (error) { - dpm_complete(msg); + dpm_complete(PMSG_RECOVER); goto Cleanup; } suspend_console(); pm_restrict_gfp_mask(); + error = dpm_suspend(PMSG_FREEZE); - if (error) - goto Recover_platform; - if (hibernation_test(TEST_DEVICES)) - goto Recover_platform; + if (error || hibernation_test(TEST_DEVICES)) + platform_recover(platform_mode); + else + error = create_image(platform_mode); - error = create_image(platform_mode); /* - * Control returns here (1) after the image has been created or the + * In the case that we call create_image() above, the control + * returns here (1) after the image has been created or the * image creation has failed and (2) after a successful restore. */ - Resume_devices: /* We may need to release the preallocated image pages here. */ if (error || !in_suspend) swsusp_free(); @@ -399,10 +399,6 @@ int hibernation_snapshot(int platform_mode) platform_end(platform_mode); return error; - Recover_platform: - platform_recover(platform_mode); - goto Resume_devices; - Cleanup: swsusp_free(); goto Close; -- cgit v1.2.1 From 0118521cc7acb3ccbc1a01d6144ac32be9d56a4c Mon Sep 17 00:00:00 2001 From: "Srivatsa S. Bhat" Date: Thu, 1 Dec 2011 22:32:43 +0100 Subject: PM / Hibernate: Enable usermodehelpers in software_resume() error path In the software_resume() function defined in kernel/power/hibernate.c, if the call to create_basic_memory_bitmaps() fails, the usermodehelpers are not enabled (which had been disabled in the previous step). Fix it. Signed-off-by: Srivatsa S. Bhat Signed-off-by: Rafael J. Wysocki --- kernel/power/hibernate.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'kernel/power/hibernate.c') diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c index ebf62c3bc9f7..1fcf9de4506d 100644 --- a/kernel/power/hibernate.c +++ b/kernel/power/hibernate.c @@ -807,8 +807,10 @@ static int software_resume(void) goto close_finish; error = create_basic_memory_bitmaps(); - if (error) + if (error) { + usermodehelper_enable(); goto close_finish; + } pr_debug("PM: Preparing processes for restore.\n"); error = prepare_processes(); -- cgit v1.2.1 From 97819a26224f019e73d88bb2fd4eb5a614860461 Mon Sep 17 00:00:00 2001 From: "Srivatsa S. Bhat" Date: Thu, 1 Dec 2011 22:33:10 +0100 Subject: PM / Hibernate: Thaw processes in SNAPSHOT_CREATE_IMAGE ioctl test path Commit 2aede851ddf08666f68ffc17be446420e9d2a056 (PM / Hibernate: Freeze kernel threads after preallocating memory) moved the freezing of kernel threads to hibernation_snapshot() function. So now, if the call to hibernation_snapshot() returns early due to a successful hibernation test, the caller has to thaw processes to ensure that the system gets back to its original state. But in SNAPSHOT_CREATE_IMAGE hibernation ioctl, the caller does not thaw processes in case hibernation_snapshot() returned due to a successful freezer test. Fix this issue. But note we still send the value of 'in_suspend' (which is now 0) to userspace, because we are not in an error path per-se, and moreover, the value of in_suspend correctly depicts the situation here. Signed-off-by: Srivatsa S. Bhat Signed-off-by: Rafael J. Wysocki --- kernel/power/hibernate.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'kernel/power/hibernate.c') diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c index 1fcf9de4506d..c10cb0f916e2 100644 --- a/kernel/power/hibernate.c +++ b/kernel/power/hibernate.c @@ -55,7 +55,7 @@ enum { static int hibernation_mode = HIBERNATION_SHUTDOWN; -static bool freezer_test_done; +bool freezer_test_done; static const struct platform_hibernation_ops *hibernation_ops; -- cgit v1.2.1 From 48580ab8729865c81e148d59159fbe2aa7865511 Mon Sep 17 00:00:00 2001 From: "Srivatsa S. Bhat" Date: Thu, 1 Dec 2011 22:33:20 +0100 Subject: PM / Hibernate: Remove deprecated hibernation test modes The hibernation test modes 'test' and 'testproc' are deprecated, because the 'pm_test' framework offers much more fine-grained control for debugging suspend and hibernation related problems. So, remove the deprecated 'test' and 'testproc' hibernation test modes. Suggested-by: Rafael J. Wysocki Signed-off-by: Srivatsa S. Bhat Signed-off-by: Rafael J. Wysocki --- kernel/power/hibernate.c | 33 ++++----------------------------- 1 file changed, 4 insertions(+), 29 deletions(-) (limited to 'kernel/power/hibernate.c') diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c index c10cb0f916e2..5314a94a92c1 100644 --- a/kernel/power/hibernate.c +++ b/kernel/power/hibernate.c @@ -43,8 +43,6 @@ int in_suspend __nosavedata; enum { HIBERNATION_INVALID, HIBERNATION_PLATFORM, - HIBERNATION_TEST, - HIBERNATION_TESTPROC, HIBERNATION_SHUTDOWN, HIBERNATION_REBOOT, /* keep last */ @@ -96,15 +94,6 @@ static void hibernation_debug_sleep(void) mdelay(5000); } -static int hibernation_testmode(int mode) -{ - if (hibernation_mode == mode) { - hibernation_debug_sleep(); - return 1; - } - return 0; -} - static int hibernation_test(int level) { if (pm_test_level == level) { @@ -114,7 +103,6 @@ static int hibernation_test(int level) return 0; } #else /* !CONFIG_PM_DEBUG */ -static int hibernation_testmode(int mode) { return 0; } static int hibernation_test(int level) { return 0; } #endif /* !CONFIG_PM_DEBUG */ @@ -278,8 +266,7 @@ static int create_image(int platform_mode) goto Platform_finish; error = disable_nonboot_cpus(); - if (error || hibernation_test(TEST_CPUS) - || hibernation_testmode(HIBERNATION_TEST)) + if (error || hibernation_test(TEST_CPUS)) goto Enable_cpus; local_irq_disable(); @@ -349,8 +336,7 @@ int hibernation_snapshot(int platform_mode) if (error) goto Cleanup; - if (hibernation_test(TEST_FREEZER) || - hibernation_testmode(HIBERNATION_TESTPROC)) { + if (hibernation_test(TEST_FREEZER)) { /* * Indicate to the caller that we are returning due to a @@ -586,9 +572,6 @@ int hibernation_platform_enter(void) static void power_down(void) { switch (hibernation_mode) { - case HIBERNATION_TEST: - case HIBERNATION_TESTPROC: - break; case HIBERNATION_REBOOT: kernel_restart(NULL); break; @@ -853,8 +836,6 @@ static const char * const hibernation_modes[] = { [HIBERNATION_PLATFORM] = "platform", [HIBERNATION_SHUTDOWN] = "shutdown", [HIBERNATION_REBOOT] = "reboot", - [HIBERNATION_TEST] = "test", - [HIBERNATION_TESTPROC] = "testproc", }; /* @@ -863,17 +844,15 @@ static const char * const hibernation_modes[] = { * Hibernation can be handled in several ways. There are a few different ways * to put the system into the sleep state: using the platform driver (e.g. ACPI * or other hibernation_ops), powering it off or rebooting it (for testing - * mostly), or using one of the two available test modes. + * mostly). * * The sysfs file /sys/power/disk provides an interface for selecting the * hibernation mode to use. Reading from this file causes the available modes - * to be printed. There are 5 modes that can be supported: + * to be printed. There are 3 modes that can be supported: * * 'platform' * 'shutdown' * 'reboot' - * 'test' - * 'testproc' * * If a platform hibernation driver is in use, 'platform' will be supported * and will be used by default. Otherwise, 'shutdown' will be used by default. @@ -897,8 +876,6 @@ static ssize_t disk_show(struct kobject *kobj, struct kobj_attribute *attr, switch (i) { case HIBERNATION_SHUTDOWN: case HIBERNATION_REBOOT: - case HIBERNATION_TEST: - case HIBERNATION_TESTPROC: break; case HIBERNATION_PLATFORM: if (hibernation_ops) @@ -939,8 +916,6 @@ static ssize_t disk_store(struct kobject *kobj, struct kobj_attribute *attr, switch (mode) { case HIBERNATION_SHUTDOWN: case HIBERNATION_REBOOT: - case HIBERNATION_TEST: - case HIBERNATION_TESTPROC: hibernation_mode = mode; break; case HIBERNATION_PLATFORM: -- cgit v1.2.1 From bcda53faf5814c0c6025a0bd47108adfcbe9f199 Mon Sep 17 00:00:00 2001 From: "Srivatsa S. Bhat" Date: Wed, 7 Dec 2011 22:29:54 +0100 Subject: PM / Sleep: Replace mutex_[un]lock(&pm_mutex) with [un]lock_system_sleep() Using [un]lock_system_sleep() is safer than directly using mutex_[un]lock() on 'pm_mutex', since the latter could lead to freezing failures. Hence convert all the present users of mutex_[un]lock(&pm_mutex) to use these safe APIs instead. Suggested-by: Tejun Heo Signed-off-by: Srivatsa S. Bhat Reviewed-by: Simon Horman Signed-off-by: Rafael J. Wysocki --- kernel/power/hibernate.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) (limited to 'kernel/power/hibernate.c') diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c index 605149a6d219..6d6d28870335 100644 --- a/kernel/power/hibernate.c +++ b/kernel/power/hibernate.c @@ -69,14 +69,14 @@ void hibernation_set_ops(const struct platform_hibernation_ops *ops) WARN_ON(1); return; } - mutex_lock(&pm_mutex); + lock_system_sleep(); hibernation_ops = ops; if (ops) hibernation_mode = HIBERNATION_PLATFORM; else if (hibernation_mode == HIBERNATION_PLATFORM) hibernation_mode = HIBERNATION_SHUTDOWN; - mutex_unlock(&pm_mutex); + unlock_system_sleep(); } static bool entering_platform_hibernation; @@ -597,7 +597,7 @@ int hibernate(void) { int error; - mutex_lock(&pm_mutex); + lock_system_sleep(); /* The snapshot device should not be opened while we're running */ if (!atomic_add_unless(&snapshot_device_available, -1, 0)) { error = -EBUSY; @@ -665,7 +665,7 @@ int hibernate(void) pm_restore_console(); atomic_inc(&snapshot_device_available); Unlock: - mutex_unlock(&pm_mutex); + unlock_system_sleep(); return error; } @@ -893,7 +893,7 @@ static ssize_t disk_store(struct kobject *kobj, struct kobj_attribute *attr, p = memchr(buf, '\n', n); len = p ? p - buf : n; - mutex_lock(&pm_mutex); + lock_system_sleep(); for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) { if (len == strlen(hibernation_modes[i]) && !strncmp(buf, hibernation_modes[i], len)) { @@ -919,7 +919,7 @@ static ssize_t disk_store(struct kobject *kobj, struct kobj_attribute *attr, if (!error) pr_debug("PM: Hibernation mode set to '%s'\n", hibernation_modes[mode]); - mutex_unlock(&pm_mutex); + unlock_system_sleep(); return error ? error : n; } @@ -946,9 +946,9 @@ static ssize_t resume_store(struct kobject *kobj, struct kobj_attribute *attr, if (maj != MAJOR(res) || min != MINOR(res)) goto out; - mutex_lock(&pm_mutex); + lock_system_sleep(); swsusp_resume_device = res; - mutex_unlock(&pm_mutex); + unlock_system_sleep(); printk(KERN_INFO "PM: Starting manual resume from disk\n"); noresume = 0; software_resume(); -- cgit v1.2.1