Commit a857b530 authored by Rafael J. Wysocki's avatar Rafael J. Wysocki
Browse files

Merge back material related to system sleep for 6.19

parents f384497a 46fc75a2

Documentation/ABI/testing/sysfs-power

+16 −0
Original line number Diff line number Diff line
@@ -454,3 +454,19 @@ Description: 
		disables it.  Reads from the file return the current value.

		The default is "1" if the build-time "SUSPEND_SKIP_SYNC" config

		flag is unset, or "0" otherwise.



What:           /sys/power/hibernate_compression_threads

Date:           October 2025

Contact:        <luoxueqin@kylinos.cn>

Description:

                Controls the number of threads used for compression

                and decompression of hibernation images.



                The value can be adjusted at runtime to balance

                performance and CPU utilization.



                The change takes effect on the next hibernation or

                resume operation.



                Minimum value: 1

                Default value: 3

Documentation/admin-guide/kernel-parameters.txt

+10 −0
Original line number Diff line number Diff line
@@ -1907,6 +1907,16 @@ 
			/sys/power/pm_test). Only available when CONFIG_PM_DEBUG

			is set. Default value is 5.



	hibernate_compression_threads=

			[HIBERNATION]

			Set the number of threads used for compressing or decompressing

			hibernation images.



			Format: <integer>

			Default: 3

			Minimum: 1

			Example: hibernate_compression_threads=4



	highmem=nn[KMG]	[KNL,BOOT,EARLY] forces the highmem zone to have an exact

			size of <nn>. This works even on boxes that have no

			highmem otherwise. This also works to reduce highmem

Documentation/power/index.rst

+1 −0
Original line number Diff line number Diff line
@@ -19,6 +19,7 @@ Power Management 
    power_supply_class

    runtime_pm

    s2ram

    shutdown-debugging

    suspend-and-cpuhotplug

    suspend-and-interrupts

    swsusp-and-swap-files

Documentation/power/shutdown-debugging.rst

0 → 100644
+53 −0
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.. SPDX-License-Identifier: GPL-2.0



Debugging Kernel Shutdown Hangs with pstore

+++++++++++++++++++++++++++++++++++++++++++



Overview

========

If the system hangs while shutting down, the kernel logs may need to be

retrieved to debug the issue.



On systems that have a UART available, it is best to configure the kernel to use

this UART for kernel console output.



If a UART isn't available, the ``pstore`` subsystem provides a mechanism to

persist this data across a system reset, allowing it to be retrieved on the next

boot.



Kernel Configuration

====================

To enable ``pstore`` and enable saving kernel ring buffer logs, set the

following kernel configuration options:



* ``CONFIG_PSTORE=y``

* ``CONFIG_PSTORE_CONSOLE=y``



Additionally, enable a backend to store the data. Depending upon your platform

some potential options include:



* ``CONFIG_EFI_VARS_PSTORE=y``

* ``CONFIG_PSTORE_RAM=y``

* ``CONFIG_CHROMEOS_PSTORE=y``

* ``CONFIG_PSTORE_BLK=y``



Kernel Command-line Parameters

==============================

Add these parameters to your kernel command line:



* ``printk.always_kmsg_dump=Y``

	* Forces the kernel to dump the entire message buffer to pstore during

		shutdown

* ``efi_pstore.pstore_disable=N``

	* For EFI-based systems, ensures the EFI backend is active



Userspace Interaction and Log Retrieval

=======================================

On the next boot after a hang, pstore logs will be available in the pstore

filesystem (``/sys/fs/pstore``) and can be retrieved by userspace.



On systemd systems, the ``systemd-pstore`` service will help do the following:



#. Locate pstore data in ``/sys/fs/pstore``

#. Read and save it to ``/var/lib/systemd/pstore``

#. Clear pstore data for the next event

drivers/base/power/generic_ops.c

+25 −60
Original line number Diff line number Diff line
@@ -8,6 +8,13 @@ 
#include <linux/pm_runtime.h>

#include <linux/export.h>



#define CALL_PM_OP(dev, op) \

({ \

	struct device *_dev = (dev); \

	const struct dev_pm_ops *pm = _dev->driver ? _dev->driver->pm : NULL; \

	pm && pm->op ? pm->op(_dev) : 0; \

})



#ifdef CONFIG_PM

/**

 * pm_generic_runtime_suspend - Generic runtime suspend callback for subsystems.
@@ -19,12 +26,7 @@ 
 */

int pm_generic_runtime_suspend(struct device *dev)

{

	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;

	int ret;



	ret = pm && pm->runtime_suspend ? pm->runtime_suspend(dev) : 0;



	return ret;

	return CALL_PM_OP(dev, runtime_suspend);

}

EXPORT_SYMBOL_GPL(pm_generic_runtime_suspend);
@@ -38,12 +40,7 @@ EXPORT_SYMBOL_GPL(pm_generic_runtime_suspend); 
 */

int pm_generic_runtime_resume(struct device *dev)

{

	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;

	int ret;



	ret = pm && pm->runtime_resume ? pm->runtime_resume(dev) : 0;



	return ret;

	return CALL_PM_OP(dev, runtime_resume);

}

EXPORT_SYMBOL_GPL(pm_generic_runtime_resume);

#endif /* CONFIG_PM */
@@ -72,9 +69,7 @@ int pm_generic_prepare(struct device *dev) 
 */

int pm_generic_suspend_noirq(struct device *dev)

{

	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;



	return pm && pm->suspend_noirq ? pm->suspend_noirq(dev) : 0;

	return CALL_PM_OP(dev, suspend_noirq);

}

EXPORT_SYMBOL_GPL(pm_generic_suspend_noirq);
@@ -84,9 +79,7 @@ EXPORT_SYMBOL_GPL(pm_generic_suspend_noirq); 
 */

int pm_generic_suspend_late(struct device *dev)

{

	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;



	return pm && pm->suspend_late ? pm->suspend_late(dev) : 0;

	return CALL_PM_OP(dev, suspend_late);

}

EXPORT_SYMBOL_GPL(pm_generic_suspend_late);
@@ -96,9 +89,7 @@ EXPORT_SYMBOL_GPL(pm_generic_suspend_late); 
 */

int pm_generic_suspend(struct device *dev)

{

	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;



	return pm && pm->suspend ? pm->suspend(dev) : 0;

	return CALL_PM_OP(dev, suspend);

}

EXPORT_SYMBOL_GPL(pm_generic_suspend);
@@ -108,9 +99,7 @@ EXPORT_SYMBOL_GPL(pm_generic_suspend); 
 */

int pm_generic_freeze_noirq(struct device *dev)

{

	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;



	return pm && pm->freeze_noirq ? pm->freeze_noirq(dev) : 0;

	return CALL_PM_OP(dev, freeze_noirq);

}

EXPORT_SYMBOL_GPL(pm_generic_freeze_noirq);
@@ -120,9 +109,7 @@ EXPORT_SYMBOL_GPL(pm_generic_freeze_noirq); 
 */

int pm_generic_freeze(struct device *dev)

{

	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;



	return pm && pm->freeze ? pm->freeze(dev) : 0;

	return CALL_PM_OP(dev, freeze);

}

EXPORT_SYMBOL_GPL(pm_generic_freeze);
@@ -132,9 +119,7 @@ EXPORT_SYMBOL_GPL(pm_generic_freeze); 
 */

int pm_generic_poweroff_noirq(struct device *dev)

{

	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;



	return pm && pm->poweroff_noirq ? pm->poweroff_noirq(dev) : 0;

	return CALL_PM_OP(dev, poweroff_noirq);

}

EXPORT_SYMBOL_GPL(pm_generic_poweroff_noirq);
@@ -144,9 +129,7 @@ EXPORT_SYMBOL_GPL(pm_generic_poweroff_noirq); 
 */

int pm_generic_poweroff_late(struct device *dev)

{

	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;



	return pm && pm->poweroff_late ? pm->poweroff_late(dev) : 0;

	return CALL_PM_OP(dev, poweroff_late);

}

EXPORT_SYMBOL_GPL(pm_generic_poweroff_late);
@@ -156,9 +139,7 @@ EXPORT_SYMBOL_GPL(pm_generic_poweroff_late); 
 */

int pm_generic_poweroff(struct device *dev)

{

	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;



	return pm && pm->poweroff ? pm->poweroff(dev) : 0;

	return CALL_PM_OP(dev, poweroff);

}

EXPORT_SYMBOL_GPL(pm_generic_poweroff);
@@ -168,9 +149,7 @@ EXPORT_SYMBOL_GPL(pm_generic_poweroff); 
 */

int pm_generic_thaw_noirq(struct device *dev)

{

	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;



	return pm && pm->thaw_noirq ? pm->thaw_noirq(dev) : 0;

	return CALL_PM_OP(dev, thaw_noirq);

}

EXPORT_SYMBOL_GPL(pm_generic_thaw_noirq);
@@ -180,9 +159,7 @@ EXPORT_SYMBOL_GPL(pm_generic_thaw_noirq); 
 */

int pm_generic_thaw(struct device *dev)

{

	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;



	return pm && pm->thaw ? pm->thaw(dev) : 0;

	return CALL_PM_OP(dev, thaw);

}

EXPORT_SYMBOL_GPL(pm_generic_thaw);
@@ -192,9 +169,7 @@ EXPORT_SYMBOL_GPL(pm_generic_thaw); 
 */

int pm_generic_resume_noirq(struct device *dev)

{

	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;



	return pm && pm->resume_noirq ? pm->resume_noirq(dev) : 0;

	return CALL_PM_OP(dev, resume_noirq);

}

EXPORT_SYMBOL_GPL(pm_generic_resume_noirq);
@@ -204,9 +179,7 @@ EXPORT_SYMBOL_GPL(pm_generic_resume_noirq); 
 */

int pm_generic_resume_early(struct device *dev)

{

	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;



	return pm && pm->resume_early ? pm->resume_early(dev) : 0;

	return CALL_PM_OP(dev, resume_early);

}

EXPORT_SYMBOL_GPL(pm_generic_resume_early);
@@ -216,9 +189,7 @@ EXPORT_SYMBOL_GPL(pm_generic_resume_early); 
 */

int pm_generic_resume(struct device *dev)

{

	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;



	return pm && pm->resume ? pm->resume(dev) : 0;

	return CALL_PM_OP(dev, resume);

}

EXPORT_SYMBOL_GPL(pm_generic_resume);
@@ -228,9 +199,7 @@ EXPORT_SYMBOL_GPL(pm_generic_resume); 
 */

int pm_generic_restore_noirq(struct device *dev)

{

	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;



	return pm && pm->restore_noirq ? pm->restore_noirq(dev) : 0;

	return CALL_PM_OP(dev, restore_noirq);

}

EXPORT_SYMBOL_GPL(pm_generic_restore_noirq);
@@ -240,9 +209,7 @@ EXPORT_SYMBOL_GPL(pm_generic_restore_noirq); 
 */

int pm_generic_restore_early(struct device *dev)

{

	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;



	return pm && pm->restore_early ? pm->restore_early(dev) : 0;

	return CALL_PM_OP(dev, restore_early);

}

EXPORT_SYMBOL_GPL(pm_generic_restore_early);
@@ -252,9 +219,7 @@ EXPORT_SYMBOL_GPL(pm_generic_restore_early); 
 */

int pm_generic_restore(struct device *dev)

{

	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;



	return pm && pm->restore ? pm->restore(dev) : 0;

	return CALL_PM_OP(dev, restore);

}

EXPORT_SYMBOL_GPL(pm_generic_restore);