Merge branch 'perf/core' into perf/uprobes

Merge in latest upstream (and the latest perf development tree),
to prepare for tooling changes, and also to pick up v3.4 MM
changes that the uprobes code needs to take care of.

Signed-off-by: Ingo Molnar <mingo@kernel.org>

9 files changed, 180 insertions, 162 deletions

diff --git a/kernel/power/Makefile b/kernel/power/Makefile
index 07e0e28ffba7..66d808ec5252 100644
--- a/kernel/power/Makefile
+++ b/kernel/power/Makefile
@@ -1,7 +1,8 @@
 
 ccflags-$(CONFIG_PM_DEBUG)	:= -DDEBUG
 
-obj-$(CONFIG_PM)		+= main.o qos.o
+obj-y				+= qos.o
+obj-$(CONFIG_PM)		+= main.o
 obj-$(CONFIG_VT_CONSOLE_SLEEP)	+= console.o
 obj-$(CONFIG_FREEZER)		+= process.o
 obj-$(CONFIG_SUSPEND)		+= suspend.o
diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c
index 6d6d28870335..e09dfbfeecee 100644
--- a/kernel/power/hibernate.c
+++ b/kernel/power/hibernate.c
@@ -16,7 +16,6 @@
 #include <linux/string.h>
 #include <linux/device.h>
 #include <linux/async.h>
-#include <linux/kmod.h>
 #include <linux/delay.h>
 #include <linux/fs.h>
 #include <linux/mount.h>
@@ -245,8 +244,8 @@ void swsusp_show_speed(struct timeval *start, struct timeval *stop,
  * create_image - Create a hibernation image.
  * @platform_mode: Whether or not to use the platform driver.
  *
- * Execute device drivers' .freeze_noirq() callbacks, create a hibernation image
- * and execute the drivers' .thaw_noirq() callbacks.
+ * Execute device drivers' "late" and "noirq" freeze callbacks, create a
+ * hibernation image and run the drivers' "noirq" and "early" thaw callbacks.
  *
  * Control reappears in this routine after the subsequent restore.
  */
@@ -254,7 +253,7 @@ static int create_image(int platform_mode)
 {
 	int error;
 
-	error = dpm_suspend_noirq(PMSG_FREEZE);
+	error = dpm_suspend_end(PMSG_FREEZE);
 	if (error) {
 		printk(KERN_ERR "PM: Some devices failed to power down, "
 			"aborting hibernation\n");
@@ -306,7 +305,7 @@ static int create_image(int platform_mode)
  Platform_finish:
 	platform_finish(platform_mode);
 
-	dpm_resume_noirq(in_suspend ?
+	dpm_resume_start(in_suspend ?
 		(error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE);
 
 	return error;
@@ -343,13 +342,13 @@ int hibernation_snapshot(int platform_mode)
 		 * successful freezer test.
 		 */
 		freezer_test_done = true;
-		goto Cleanup;
+		goto Thaw;
 	}
 
 	error = dpm_prepare(PMSG_FREEZE);
 	if (error) {
 		dpm_complete(PMSG_RECOVER);
-		goto Cleanup;
+		goto Thaw;
 	}
 
 	suspend_console();
@@ -385,6 +384,8 @@ int hibernation_snapshot(int platform_mode)
 	platform_end(platform_mode);
 	return error;
 
+ Thaw:
+	thaw_kernel_threads();
  Cleanup:
 	swsusp_free();
 	goto Close;
@@ -394,16 +395,16 @@ int hibernation_snapshot(int platform_mode)
  * resume_target_kernel - Restore system state from a hibernation image.
  * @platform_mode: Whether or not to use the platform driver.
  *
- * Execute device drivers' .freeze_noirq() callbacks, restore the contents of
- * highmem that have not been restored yet from the image and run the low-level
- * code that will restore the remaining contents of memory and switch to the
- * just restored target kernel.
+ * Execute device drivers' "noirq" and "late" freeze callbacks, restore the
+ * contents of highmem that have not been restored yet from the image and run
+ * the low-level code that will restore the remaining contents of memory and
+ * switch to the just restored target kernel.
  */
 static int resume_target_kernel(bool platform_mode)
 {
 	int error;
 
-	error = dpm_suspend_noirq(PMSG_QUIESCE);
+	error = dpm_suspend_end(PMSG_QUIESCE);
 	if (error) {
 		printk(KERN_ERR "PM: Some devices failed to power down, "
 			"aborting resume\n");
@@ -460,7 +461,7 @@ static int resume_target_kernel(bool platform_mode)
  Cleanup:
 	platform_restore_cleanup(platform_mode);
 
-	dpm_resume_noirq(PMSG_RECOVER);
+	dpm_resume_start(PMSG_RECOVER);
 
 	return error;
 }
@@ -518,7 +519,7 @@ int hibernation_platform_enter(void)
 		goto Resume_devices;
 	}
 
-	error = dpm_suspend_noirq(PMSG_HIBERNATE);
+	error = dpm_suspend_end(PMSG_HIBERNATE);
 	if (error)
 		goto Resume_devices;
 
@@ -549,7 +550,7 @@ int hibernation_platform_enter(void)
  Platform_finish:
 	hibernation_ops->finish();
 
-	dpm_resume_noirq(PMSG_RESTORE);
+	dpm_resume_start(PMSG_RESTORE);
 
  Resume_devices:
 	entering_platform_hibernation = false;
@@ -609,10 +610,6 @@ int hibernate(void)
 	if (error)
 		goto Exit;
 
-	error = usermodehelper_disable();
-	if (error)
-		goto Exit;
-
 	/* Allocate memory management structures */
 	error = create_basic_memory_bitmaps();
 	if (error)
@@ -624,15 +621,11 @@ int hibernate(void)
 
 	error = freeze_processes();
 	if (error)
-		goto Finish;
+		goto Free_bitmaps;
 
 	error = hibernation_snapshot(hibernation_mode == HIBERNATION_PLATFORM);
-	if (error)
-		goto Thaw;
-	if (freezer_test_done) {
-		freezer_test_done = false;
+	if (error || freezer_test_done)
 		goto Thaw;
-	}
 
 	if (in_suspend) {
 		unsigned int flags = 0;
@@ -657,9 +650,12 @@ int hibernate(void)
 
  Thaw:
 	thaw_processes();
- Finish:
+
+	/* Don't bother checking whether freezer_test_done is true */
+	freezer_test_done = false;
+
+ Free_bitmaps:
 	free_basic_memory_bitmaps();
-	usermodehelper_enable();
  Exit:
 	pm_notifier_call_chain(PM_POST_HIBERNATION);
 	pm_restore_console();
@@ -774,15 +770,9 @@ static int software_resume(void)
 	if (error)
 		goto close_finish;
 
-	error = usermodehelper_disable();
-	if (error)
-		goto close_finish;
-
 	error = create_basic_memory_bitmaps();
-	if (error) {
-		usermodehelper_enable();
+	if (error)
 		goto close_finish;
-	}
 
 	pr_debug("PM: Preparing processes for restore.\n");
 	error = freeze_processes();
@@ -803,7 +793,6 @@ static int software_resume(void)
 	thaw_processes();
  Done:
 	free_basic_memory_bitmaps();
-	usermodehelper_enable();
  Finish:
 	pm_notifier_call_chain(PM_POST_RESTORE);
 	pm_restore_console();
diff --git a/kernel/power/main.c b/kernel/power/main.c
index 9824b41e5a18..1c12581f1c62 100644
--- a/kernel/power/main.c
+++ b/kernel/power/main.c
@@ -165,16 +165,20 @@ static int suspend_stats_show(struct seq_file *s, void *unused)
 	last_errno %= REC_FAILED_NUM;
 	last_step = suspend_stats.last_failed_step + REC_FAILED_NUM - 1;
 	last_step %= REC_FAILED_NUM;
-	seq_printf(s, "%s: %d\n%s: %d\n%s: %d\n%s: %d\n"
-			"%s: %d\n%s: %d\n%s: %d\n%s: %d\n",
+	seq_printf(s, "%s: %d\n%s: %d\n%s: %d\n%s: %d\n%s: %d\n"
+			"%s: %d\n%s: %d\n%s: %d\n%s: %d\n%s: %d\n",
 			"success", suspend_stats.success,
 			"fail", suspend_stats.fail,
 			"failed_freeze", suspend_stats.failed_freeze,
 			"failed_prepare", suspend_stats.failed_prepare,
 			"failed_suspend", suspend_stats.failed_suspend,
+			"failed_suspend_late",
+				suspend_stats.failed_suspend_late,
 			"failed_suspend_noirq",
 				suspend_stats.failed_suspend_noirq,
 			"failed_resume", suspend_stats.failed_resume,
+			"failed_resume_early",
+				suspend_stats.failed_resume_early,
 			"failed_resume_noirq",
 				suspend_stats.failed_resume_noirq);
 	seq_printf(s,	"failures:\n  last_failed_dev:\t%-s\n",
@@ -287,16 +291,10 @@ static ssize_t state_store(struct kobject *kobj, struct kobj_attribute *attr,
 
 #ifdef CONFIG_SUSPEND
 	for (s = &pm_states[state]; state < PM_SUSPEND_MAX; s++, state++) {
-		if (*s && len == strlen(*s) && !strncmp(buf, *s, len))
+		if (*s && len == strlen(*s) && !strncmp(buf, *s, len)) {
+			error = pm_suspend(state);
 			break;
-	}
-	if (state < PM_SUSPEND_MAX && *s) {
-		error = enter_state(state);
-		if (error) {
-			suspend_stats.fail++;
-			dpm_save_failed_errno(error);
-		} else
-			suspend_stats.success++;
+		}
 	}
 #endif
 
diff --git a/kernel/power/power.h b/kernel/power/power.h
index 21724eee5206..98f3622d7407 100644
--- a/kernel/power/power.h
+++ b/kernel/power/power.h
@@ -177,13 +177,11 @@ extern const char *const pm_states[];
 
 extern bool valid_state(suspend_state_t state);
 extern int suspend_devices_and_enter(suspend_state_t state);
-extern int enter_state(suspend_state_t state);
 #else /* !CONFIG_SUSPEND */
 static inline int suspend_devices_and_enter(suspend_state_t state)
 {
 	return -ENOSYS;
 }
-static inline int enter_state(suspend_state_t state) { return -ENOSYS; }
 static inline bool valid_state(suspend_state_t state) { return false; }
 #endif /* !CONFIG_SUSPEND */
 
@@ -234,16 +232,14 @@ static inline int suspend_freeze_processes(void)
 	int error;
 
 	error = freeze_processes();
-
 	/*
 	 * freeze_processes() automatically thaws every task if freezing
 	 * fails. So we need not do anything extra upon error.
 	 */
 	if (error)
-		goto Finish;
+		return error;
 
 	error = freeze_kernel_threads();
-
 	/*
 	 * freeze_kernel_threads() thaws only kernel threads upon freezing
 	 * failure. So we have to thaw the userspace tasks ourselves.
@@ -251,7 +247,6 @@ static inline int suspend_freeze_processes(void)
 	if (error)
 		thaw_processes();
 
- Finish:
 	return error;
 }
 
diff --git a/kernel/power/process.c b/kernel/power/process.c
index 7e426459e60a..19db29f67558 100644
--- a/kernel/power/process.c
+++ b/kernel/power/process.c
@@ -16,6 +16,7 @@
 #include <linux/freezer.h>
 #include <linux/delay.h>
 #include <linux/workqueue.h>
+#include <linux/kmod.h>
 
 /* 
  * Timeout for stopping processes
@@ -53,11 +54,9 @@ static int try_to_freeze_tasks(bool user_only)
 			 * It is "frozen enough".  If the task does wake
 			 * up, it will immediately call try_to_freeze.
 			 *
-			 * Because freeze_task() goes through p's
-			 * scheduler lock after setting TIF_FREEZE, it's
-			 * guaranteed that either we see TASK_RUNNING or
-			 * try_to_stop() after schedule() in ptrace/signal
-			 * stop sees TIF_FREEZE.
+			 * Because freeze_task() goes through p's scheduler lock, it's
+			 * guaranteed that TASK_STOPPED/TRACED -> TASK_RUNNING
+			 * transition can't race with task state testing here.
 			 */
 			if (!task_is_stopped_or_traced(p) &&
 			    !freezer_should_skip(p))
@@ -98,13 +97,15 @@ static int try_to_freeze_tasks(bool user_only)
 		       elapsed_csecs / 100, elapsed_csecs % 100,
 		       todo - wq_busy, wq_busy);
 
-		read_lock(&tasklist_lock);
-		do_each_thread(g, p) {
-			if (!wakeup && !freezer_should_skip(p) &&
-			    p != current && freezing(p) && !frozen(p))
-				sched_show_task(p);
-		} while_each_thread(g, p);
-		read_unlock(&tasklist_lock);
+		if (!wakeup) {
+			read_lock(&tasklist_lock);
+			do_each_thread(g, p) {
+				if (p != current && !freezer_should_skip(p)
+				    && freezing(p) && !frozen(p))
+					sched_show_task(p);
+			} while_each_thread(g, p);
+			read_unlock(&tasklist_lock);
+		}
 	} else {
 		printk("(elapsed %d.%02d seconds) ", elapsed_csecs / 100,
 			elapsed_csecs % 100);
@@ -122,6 +123,10 @@ int freeze_processes(void)
 {
 	int error;
 
+	error = __usermodehelper_disable(UMH_FREEZING);
+	if (error)
+		return error;
+
 	if (!pm_freezing)
 		atomic_inc(&system_freezing_cnt);
 
@@ -130,6 +135,7 @@ int freeze_processes(void)
 	error = try_to_freeze_tasks(true);
 	if (!error) {
 		printk("done.");
+		__usermodehelper_set_disable_depth(UMH_DISABLED);
 		oom_killer_disable();
 	}
 	printk("\n");
@@ -187,6 +193,8 @@ void thaw_processes(void)
 	} while_each_thread(g, p);
 	read_unlock(&tasklist_lock);
 
+	usermodehelper_enable();
+
 	schedule();
 	printk("done.\n");
 }
diff --git a/kernel/power/qos.c b/kernel/power/qos.c
index 995e3bd3417b..6a031e684026 100644
--- a/kernel/power/qos.c
+++ b/kernel/power/qos.c
@@ -230,6 +230,21 @@ int pm_qos_request_active(struct pm_qos_request *req)
 EXPORT_SYMBOL_GPL(pm_qos_request_active);
 
 /**
+ * pm_qos_work_fn - the timeout handler of pm_qos_update_request_timeout
+ * @work: work struct for the delayed work (timeout)
+ *
+ * This cancels the timeout request by falling back to the default at timeout.
+ */
+static void pm_qos_work_fn(struct work_struct *work)
+{
+	struct pm_qos_request *req = container_of(to_delayed_work(work),
+						  struct pm_qos_request,
+						  work);
+
+	pm_qos_update_request(req, PM_QOS_DEFAULT_VALUE);
+}
+
+/**
  * pm_qos_add_request - inserts new qos request into the list
  * @req: pointer to a preallocated handle
  * @pm_qos_class: identifies which list of qos request to use
@@ -253,6 +268,7 @@ void pm_qos_add_request(struct pm_qos_request *req,
 		return;
 	}
 	req->pm_qos_class = pm_qos_class;
+	INIT_DELAYED_WORK(&req->work, pm_qos_work_fn);
 	pm_qos_update_target(pm_qos_array[pm_qos_class]->constraints,
 			     &req->node, PM_QOS_ADD_REQ, value);
 }
@@ -279,6 +295,9 @@ void pm_qos_update_request(struct pm_qos_request *req,
 		return;
 	}
 
+	if (delayed_work_pending(&req->work))
+		cancel_delayed_work_sync(&req->work);
+
 	if (new_value != req->node.prio)
 		pm_qos_update_target(
 			pm_qos_array[req->pm_qos_class]->constraints,
@@ -287,6 +306,34 @@ void pm_qos_update_request(struct pm_qos_request *req,
 EXPORT_SYMBOL_GPL(pm_qos_update_request);
 
 /**
+ * pm_qos_update_request_timeout - modifies an existing qos request temporarily.
+ * @req : handle to list element holding a pm_qos request to use
+ * @new_value: defines the temporal qos request
+ * @timeout_us: the effective duration of this qos request in usecs.
+ *
+ * After timeout_us, this qos request is cancelled automatically.
+ */
+void pm_qos_update_request_timeout(struct pm_qos_request *req, s32 new_value,
+				   unsigned long timeout_us)
+{
+	if (!req)
+		return;
+	if (WARN(!pm_qos_request_active(req),
+		 "%s called for unknown object.", __func__))
+		return;
+
+	if (delayed_work_pending(&req->work))
+		cancel_delayed_work_sync(&req->work);
+
+	if (new_value != req->node.prio)
+		pm_qos_update_target(
+			pm_qos_array[req->pm_qos_class]->constraints,
+			&req->node, PM_QOS_UPDATE_REQ, new_value);
+
+	schedule_delayed_work(&req->work, usecs_to_jiffies(timeout_us));
+}
+
+/**
  * pm_qos_remove_request - modifies an existing qos request
  * @req: handle to request list element
  *
@@ -305,6 +352,9 @@ void pm_qos_remove_request(struct pm_qos_request *req)
 		return;
 	}
 
+	if (delayed_work_pending(&req->work))
+		cancel_delayed_work_sync(&req->work);
+
 	pm_qos_update_target(pm_qos_array[req->pm_qos_class]->constraints,
 			     &req->node, PM_QOS_REMOVE_REQ,
 			     PM_QOS_DEFAULT_VALUE);
@@ -469,21 +519,18 @@ static ssize_t pm_qos_power_write(struct file *filp, const char __user *buf,
 static int __init pm_qos_power_init(void)
 {
 	int ret = 0;
+	int i;
 
-	ret = register_pm_qos_misc(&cpu_dma_pm_qos);
-	if (ret < 0) {
-		printk(KERN_ERR "pm_qos_param: cpu_dma_latency setup failed\n");
-		return ret;
-	}
-	ret = register_pm_qos_misc(&network_lat_pm_qos);
-	if (ret < 0) {
-		printk(KERN_ERR "pm_qos_param: network_latency setup failed\n");
-		return ret;
+	BUILD_BUG_ON(ARRAY_SIZE(pm_qos_array) != PM_QOS_NUM_CLASSES);
+
+	for (i = 1; i < PM_QOS_NUM_CLASSES; i++) {
+		ret = register_pm_qos_misc(pm_qos_array[i]);
+		if (ret < 0) {
+			printk(KERN_ERR "pm_qos_param: %s setup failed\n",
+			       pm_qos_array[i]->name);
+			return ret;
+		}
 	}
-	ret = register_pm_qos_misc(&network_throughput_pm_qos);
-	if (ret < 0)
-		printk(KERN_ERR
-			"pm_qos_param: network_throughput setup failed\n");
 
 	return ret;
 }
diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c
index 6a768e537001..0de28576807d 100644
--- a/kernel/power/snapshot.c
+++ b/kernel/power/snapshot.c
@@ -711,9 +711,10 @@ static void mark_nosave_pages(struct memory_bitmap *bm)
 	list_for_each_entry(region, &nosave_regions, list) {
 		unsigned long pfn;
 
-		pr_debug("PM: Marking nosave pages: %016lx - %016lx\n",
-				region->start_pfn << PAGE_SHIFT,
-				region->end_pfn << PAGE_SHIFT);
+		pr_debug("PM: Marking nosave pages: [mem %#010llx-%#010llx]\n",
+			 (unsigned long long) region->start_pfn << PAGE_SHIFT,
+			 ((unsigned long long) region->end_pfn << PAGE_SHIFT)
+				- 1);
 
 		for (pfn = region->start_pfn; pfn < region->end_pfn; pfn++)
 			if (pfn_valid(pfn)) {
@@ -1000,20 +1001,20 @@ static void copy_data_page(unsigned long dst_pfn, unsigned long src_pfn)
 	s_page = pfn_to_page(src_pfn);
 	d_page = pfn_to_page(dst_pfn);
 	if (PageHighMem(s_page)) {
-		src = kmap_atomic(s_page, KM_USER0);
-		dst = kmap_atomic(d_page, KM_USER1);
+		src = kmap_atomic(s_page);
+		dst = kmap_atomic(d_page);
 		do_copy_page(dst, src);
-		kunmap_atomic(dst, KM_USER1);
-		kunmap_atomic(src, KM_USER0);
+		kunmap_atomic(dst);
+		kunmap_atomic(src);
 	} else {
 		if (PageHighMem(d_page)) {
 			/* Page pointed to by src may contain some kernel
 			 * data modified by kmap_atomic()
 			 */
 			safe_copy_page(buffer, s_page);
-			dst = kmap_atomic(d_page, KM_USER0);
+			dst = kmap_atomic(d_page);
 			copy_page(dst, buffer);
-			kunmap_atomic(dst, KM_USER0);
+			kunmap_atomic(dst);
 		} else {
 			safe_copy_page(page_address(d_page), s_page);
 		}
@@ -1728,9 +1729,9 @@ int snapshot_read_next(struct snapshot_handle *handle)
 			 */
 			void *kaddr;
 
-			kaddr = kmap_atomic(page, KM_USER0);
+			kaddr = kmap_atomic(page);
 			copy_page(buffer, kaddr);
-			kunmap_atomic(kaddr, KM_USER0);
+			kunmap_atomic(kaddr);
 			handle->buffer = buffer;
 		} else {
 			handle->buffer = page_address(page);
@@ -2014,9 +2015,9 @@ static void copy_last_highmem_page(void)
 	if (last_highmem_page) {
 		void *dst;
 
-		dst = kmap_atomic(last_highmem_page, KM_USER0);
+		dst = kmap_atomic(last_highmem_page);
 		copy_page(dst, buffer);
-		kunmap_atomic(dst, KM_USER0);
+		kunmap_atomic(dst);
 		last_highmem_page = NULL;
 	}
 }
@@ -2309,13 +2310,13 @@ swap_two_pages_data(struct page *p1, struct page *p2, void *buf)
 {
 	void *kaddr1, *kaddr2;
 
-	kaddr1 = kmap_atomic(p1, KM_USER0);
-	kaddr2 = kmap_atomic(p2, KM_USER1);
+	kaddr1 = kmap_atomic(p1);
+	kaddr2 = kmap_atomic(p2);
 	copy_page(buf, kaddr1);
 	copy_page(kaddr1, kaddr2);
 	copy_page(kaddr2, buf);
-	kunmap_atomic(kaddr2, KM_USER1);
-	kunmap_atomic(kaddr1, KM_USER0);
+	kunmap_atomic(kaddr2);
+	kunmap_atomic(kaddr1);
 }
 
 /**
diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c
index 4fd51beed879..396d262b8fd0 100644
--- a/kernel/power/suspend.c
+++ b/kernel/power/suspend.c
@@ -12,7 +12,6 @@
 #include <linux/delay.h>
 #include <linux/errno.h>
 #include <linux/init.h>
-#include <linux/kmod.h>
 #include <linux/console.h>
 #include <linux/cpu.h>
 #include <linux/syscalls.h>
@@ -37,8 +36,8 @@ const char *const pm_states[PM_SUSPEND_MAX] = {
 static const struct platform_suspend_ops *suspend_ops;
 
 /**
- *	suspend_set_ops - Set the global suspend method table.
- *	@ops:	Pointer to ops structure.
+ * suspend_set_ops - Set the global suspend method table.
+ * @ops: Suspend operations to use.
  */
 void suspend_set_ops(const struct platform_suspend_ops *ops)
 {
@@ -58,11 +57,11 @@ bool valid_state(suspend_state_t state)
 }
 
 /**
- * suspend_valid_only_mem - generic memory-only valid callback
+ * suspend_valid_only_mem - Generic memory-only valid callback.
  *
- * Platform drivers that implement mem suspend only and only need
- * to check for that in their .valid callback can use this instead
- * of rolling their own .valid callback.
+ * Platform drivers that implement mem suspend only and only need to check for
+ * that in their .valid() callback can use this instead of rolling their own
+ * .valid() callback.
  */
 int suspend_valid_only_mem(suspend_state_t state)
 {
@@ -83,10 +82,11 @@ static int suspend_test(int level)
 }
 
 /**
- *	suspend_prepare - Do prep work before entering low-power state.
+ * suspend_prepare - Prepare for entering system sleep state.
  *
- *	This is common code that is called for each state that we're entering.
- *	Run suspend notifiers, allocate a console and stop all processes.
+ * Common code run for every system sleep state that can be entered (except for
+ * hibernation).  Run suspend notifiers, allocate the "suspend" console and
+ * freeze processes.
  */
 static int suspend_prepare(void)
 {
@@ -101,17 +101,12 @@ static int suspend_prepare(void)
 	if (error)
 		goto Finish;
 
-	error = usermodehelper_disable();
-	if (error)
-		goto Finish;
-
 	error = suspend_freeze_processes();
 	if (!error)
 		return 0;
 
 	suspend_stats.failed_freeze++;
 	dpm_save_failed_step(SUSPEND_FREEZE);
-	usermodehelper_enable();
  Finish:
 	pm_notifier_call_chain(PM_POST_SUSPEND);
 	pm_restore_console();
@@ -131,9 +126,9 @@ void __attribute__ ((weak)) arch_suspend_enable_irqs(void)
 }
 
 /**
- * suspend_enter - enter the desired system sleep state.
- * @state: State to enter
- * @wakeup: Returns information that suspend should not be entered again.
+ * suspend_enter - Make the system enter the given sleep state.
+ * @state: System sleep state to enter.
+ * @wakeup: Returns information that the sleep state should not be re-entered.
  *
  * This function should be called after devices have been suspended.
  */
@@ -147,7 +142,7 @@ static int suspend_enter(suspend_state_t state, bool *wakeup)
 			goto Platform_finish;
 	}
 
-	error = dpm_suspend_noirq(PMSG_SUSPEND);
+	error = dpm_suspend_end(PMSG_SUSPEND);
 	if (error) {
 		printk(KERN_ERR "PM: Some devices failed to power down\n");
 		goto Platform_finish;
@@ -189,7 +184,7 @@ static int suspend_enter(suspend_state_t state, bool *wakeup)
 	if (suspend_ops->wake)
 		suspend_ops->wake();
 
-	dpm_resume_noirq(PMSG_RESUME);
+	dpm_resume_start(PMSG_RESUME);
 
  Platform_finish:
 	if (suspend_ops->finish)
@@ -199,9 +194,8 @@ static int suspend_enter(suspend_state_t state, bool *wakeup)
 }
 
 /**
- *	suspend_devices_and_enter - suspend devices and enter the desired system
- *				    sleep state.
- *	@state:		  state to enter
+ * suspend_devices_and_enter - Suspend devices and enter system sleep state.
+ * @state: System sleep state to enter.
  */
 int suspend_devices_and_enter(suspend_state_t state)
 {
@@ -251,30 +245,27 @@ int suspend_devices_and_enter(suspend_state_t state)
 }
 
 /**
- *	suspend_finish - Do final work before exiting suspend sequence.
+ * suspend_finish - Clean up before finishing the suspend sequence.
  *
- *	Call platform code to clean up, restart processes, and free the
- *	console that we've allocated. This is not called for suspend-to-disk.
+ * Call platform code to clean up, restart processes, and free the console that
+ * we've allocated. This routine is not called for hibernation.
  */
 static void suspend_finish(void)
 {
 	suspend_thaw_processes();
-	usermodehelper_enable();
 	pm_notifier_call_chain(PM_POST_SUSPEND);
 	pm_restore_console();
 }
 
 /**
- *	enter_state - Do common work of entering low-power state.
- *	@state:		pm_state structure for state we're entering.
+ * enter_state - Do common work needed to enter system sleep state.
+ * @state: System sleep state to enter.
  *
- *	Make sure we're the only ones trying to enter a sleep state. Fail
- *	if someone has beat us to it, since we don't want anything weird to
- *	happen when we wake up.
- *	Then, do the setup for suspend, enter the state, and cleaup (after
- *	we've woken up).
+ * Make sure that no one else is trying to put the system into a sleep state.
+ * Fail if that's not the case.  Otherwise, prepare for system suspend, make the
+ * system enter the given sleep state and clean up after wakeup.
  */
-int enter_state(suspend_state_t state)
+static int enter_state(suspend_state_t state)
 {
 	int error;
 
@@ -310,24 +301,26 @@ int enter_state(suspend_state_t state)
 }
 
 /**
- *	pm_suspend - Externally visible function for suspending system.
- *	@state:		Enumerated value of state to enter.
+ * pm_suspend - Externally visible function for suspending the system.
+ * @state: System sleep state to enter.
  *
- *	Determine whether or not value is within range, get state
- *	structure, and enter (above).
+ * Check if the value of @state represents one of the supported states,
+ * execute enter_state() and update system suspend statistics.
  */
 int pm_suspend(suspend_state_t state)
 {
-	int ret;
-	if (state > PM_SUSPEND_ON && state < PM_SUSPEND_MAX) {
-		ret = enter_state(state);
-		if (ret) {
-			suspend_stats.fail++;
-			dpm_save_failed_errno(ret);
-		} else
-			suspend_stats.success++;
-		return ret;
+	int error;
+
+	if (state <= PM_SUSPEND_ON || state >= PM_SUSPEND_MAX)
+		return -EINVAL;
+
+	error = enter_state(state);
+	if (error) {
+		suspend_stats.fail++;
+		dpm_save_failed_errno(error);
+	} else {
+		suspend_stats.success++;
 	}
-	return -EINVAL;
+	return error;
 }
 EXPORT_SYMBOL(pm_suspend);
diff --git a/kernel/power/user.c b/kernel/power/user.c
index 3e100075b13c..91b0fd021a95 100644
--- a/kernel/power/user.c
+++ b/kernel/power/user.c
@@ -12,7 +12,6 @@
 #include <linux/suspend.h>
 #include <linux/syscalls.h>
 #include <linux/reboot.h>
-#include <linux/kmod.h>
 #include <linux/string.h>
 #include <linux/device.h>
 #include <linux/miscdevice.h>
@@ -222,14 +221,8 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd,
 		sys_sync();
 		printk("done.\n");
 
-		error = usermodehelper_disable();
-		if (error)
-			break;
-
 		error = freeze_processes();
-		if (error)
-			usermodehelper_enable();
-		else
+		if (!error)
 			data->frozen = 1;
 		break;
 
@@ -238,7 +231,6 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd,
 			break;
 		pm_restore_gfp_mask();
 		thaw_processes();
-		usermodehelper_enable();
 		data->frozen = 0;
 		break;
 
@@ -249,16 +241,10 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd,
 		}
 		pm_restore_gfp_mask();
 		error = hibernation_snapshot(data->platform_support);
-		if (error) {
-			thaw_kernel_threads();
-		} else {
+		if (!error) {
 			error = put_user(in_suspend, (int __user *)arg);
-			if (!error && !freezer_test_done)
-				data->ready = 1;
-			if (freezer_test_done) {
-				freezer_test_done = false;
-				thaw_kernel_threads();
-			}
+			data->ready = !freezer_test_done && !error;
+			freezer_test_done = false;
 		}
 		break;