user/sven/linux.git/kernel/power/power.h, branch ipvs/droutbytes

kexec jump: save/restore device state

2008-07-26T19:00:04Z

This patch implements devices state save/restore before after kexec. This patch together with features in kexec_jump patch can be used for following: - A simple hibernation implementation without ACPI support. You can kexec a hibernating kernel, save the memory image of original system and shutdown the system. When resuming, you restore the memory image of original system via ordinary kexec load then jump back. - Kernel/system debug through making system snapshot. You can make system snapshot, jump back, do some thing and make another system snapshot. - Cooperative multi-kernel/system. With kexec jump, you can switch between several kernels/systems quickly without boot process except the first time. This appears like swap a whole kernel/system out/in. - A general method to call program in physical mode (paging turning off). This can be used to invoke BIOS code under Linux. The following user-space tools can be used with kexec jump: - kexec-tools needs to be patched to support kexec jump. The patches and the precompiled kexec can be download from the following URL: source: http://khibernation.sourceforge.net/download/release_v10/kexec-tools/kexec-tools-src_git_kh10.tar.bz2 patches: http://khibernation.sourceforge.net/download/release_v10/kexec-tools/kexec-tools-patches_git_kh10.tar.bz2 binary: http://khibernation.sourceforge.net/download/release_v10/kexec-tools/kexec_git_kh10 - makedumpfile with patches are used as memory image saving tool, it can exclude free pages from original kernel memory image file. The patches and the precompiled makedumpfile can be download from the following URL: source: http://khibernation.sourceforge.net/download/release_v10/makedumpfile/makedumpfile-src_cvs_kh10.tar.bz2 patches: http://khibernation.sourceforge.net/download/release_v10/makedumpfile/makedumpfile-patches_cvs_kh10.tar.bz2 binary: http://khibernation.sourceforge.net/download/release_v10/makedumpfile/makedumpfile_cvs_kh10 - An initramfs image can be used as the root file system of kexeced kernel. An initramfs image built with "BuildRoot" can be downloaded from the following URL: initramfs image: http://khibernation.sourceforge.net/download/release_v10/initramfs/rootfs_cvs_kh10.gz All user space tools above are included in the initramfs image. Usage example of simple hibernation: 1. Compile and install patched kernel with following options selected: CONFIG_X86_32=y CONFIG_RELOCATABLE=y CONFIG_KEXEC=y CONFIG_CRASH_DUMP=y CONFIG_PM=y CONFIG_HIBERNATION=y CONFIG_KEXEC_JUMP=y 2. Build an initramfs image contains kexec-tool and makedumpfile, or download the pre-built initramfs image, called rootfs.gz in following text. 3. Prepare a partition to save memory image of original kernel, called hibernating partition in following text. 4. Boot kernel compiled in step 1 (kernel A). 5. In the kernel A, load kernel compiled in step 1 (kernel B) with /sbin/kexec. The shell command line can be as follow: /sbin/kexec --load-preserve-context /boot/bzImage --mem-min=0x100000 --mem-max=0xffffff --initrd=rootfs.gz 6. Boot the kernel B with following shell command line: /sbin/kexec -e 7. The kernel B will boot as normal kexec. In kernel B the memory image of kernel A can be saved into hibernating partition as follow: jump_back_entry=`cat /proc/cmdline | tr ' ' '\n' | grep kexec_jump_back_entry | cut -d '='` echo $jump_back_entry > kexec_jump_back_entry cp /proc/vmcore dump.elf Then you can shutdown the machine as normal. 8. Boot kernel compiled in step 1 (kernel C). Use the rootfs.gz as root file system. 9. In kernel C, load the memory image of kernel A as follow: /sbin/kexec -l --args-none --entry=`cat kexec_jump_back_entry` dump.elf 10. Jump back to the kernel A as follow: /sbin/kexec -e Then, kernel A is resumed. Implementation point: To support jumping between two kernels, before jumping to (executing) the new kernel and jumping back to the original kernel, the devices are put into quiescent state, and the state of devices and CPU is saved. After jumping back from kexeced kernel and jumping to the new kernel, the state of devices and CPU are restored accordingly. The devices/CPU state save/restore code of software suspend is called to implement corresponding function. Known issues: - Because the segment number supported by sys_kexec_load is limited, hibernation image with many segments may not be load. This is planned to be eliminated by adding a new flag to sys_kexec_load to make a image can be loaded with multiple sys_kexec_load invoking. Now, only the i386 architecture is supported. Signed-off-by: Huang Ying Acked-by: Vivek Goyal Cc: "Eric W. Biederman" Cc: Pavel Machek Cc: Nigel Cunningham Cc: "Rafael J. Wysocki" Cc: Ingo Molnar Cc: Thomas Gleixner Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Suspend: Add config option to disable the freezer if architecture wants that

2008-02-01T23:30:58Z

This patch makes the freezer optional for suspend to allow the system to work (or not work) like the original PMU suspend. Signed-off-by: Johannes Berg Acked-by: Pavel Machek Signed-off-by: Rafael J. Wysocki Signed-off-by: Len Brown

Hibernation: Move low level resume to disk.c

2008-02-01T23:30:54Z

Move the low level restore code to kernel/power/disk.c , since the corresponding low level hibernation code is already there. Make restore fail if device_power_down(PMSG_PRETHAW) returns an error. Signed-off-by: Rafael J. Wysocki Acked-by: Pavel Machek Signed-off-by: Len Brown

PM: Convert PM notifiers to out-of-line code

2008-02-01T23:30:54Z

This patch (as1008b) converts the PM notifier routines from inline calls to out-of-line code. It also prevents pm_chain_head from being created when CONFIG_PM_SLEEP isn't enabled, and EXPORTs the notifier registration and unregistration routines. Signed-off-by: Alan Stern Signed-off-by: Rafael J. Wysocki Signed-off-by: Len Brown

Hibernation: New testing facility (rev. 2)

2008-02-01T23:30:54Z

Make it possible to test the hibernation core code with the help of the /sys/power/pm_test attribute introduced for suspend testing in the previous patch. Writing an appropriate string to this file causes the hibernation code to work in one of the test modes defined as follows: freezer - test the freezing of processes devices - test the freezing of processes and suspending of devices platform - test the freezing of processes, suspending of devices and platform global control methods(*) processors - test the freezing of processes, suspending of devices, platform global control methods(*) and the disabling of nonboot CPUs core - test the freezing of processes, suspending of devices, platform global control methods(*), the disabling of nonboot CPUs and suspending of platform/system devices (*) - the platform global control methods are only available on ACPI systems and are only tested if the hibernation mode is set to "platform" Then, if a hibernation is started by normal means, the hibernation core will perform its normal operations up to the point indicated by given test level. Next, it will wait for 5 seconds and carry out the resume operations needed to transition the system back to the fully functional state. Signed-off-by: Rafael J. Wysocki Acked-by: Pavel Machek Signed-off-by: Len Brown

Suspend: Testing facility (rev. 2)

2008-02-01T23:30:54Z

Introduce sysfs attribute /sys/power/pm_test allowing one to test the suspend core code. Namely, writing one of the strings: freezer devices platform processors core to this file causes the suspend code to work in one of the test modes defined as follows: freezer - test the freezing of processes devices - test the freezing of processes and suspending of devices platform - test the freezing of processes, suspending of devices and platform global control methods(*) processors - test the freezing of processes, suspending of devices, platform global control methods and the disabling of nonboot CPUs core - test the freezing of processes, suspending of devices, platform global control methods, the disabling of nonboot CPUs and suspending of platform/system devices (*) These are ACPI global control methods on ACPI systems Then, if a suspend is started by normal means, the suspend core will perform its normal operations up to the point indicated by given test level. Next, it will wait for 5 seconds and carry out the resume operations needed to transition the system back to the fully functional state. Writing "none" to /sys/power/pm_test turns the testing off. When open for reading, /sys/power/pm_test contains a space-separated list of all available tests (including "none" that represents the normal functionality) in which the current test level is indicated by square brackets. Signed-off-by: Rafael J. Wysocki Acked-by: Pavel Machek Signed-off-by: Len Brown

Hibernation: Move function prototypes to header

2008-02-01T23:30:53Z

This patch moves the prototypes of count_highmem_pages() and restore_highmem() to kernel/power/power.h Signed-off-by: Adrian Bunk Acked-by: Pavel Machek Signed-off-by: Rafael J. Wysocki Signed-off-by: Len Brown

Hibernation: Introduce exportable suspend ioctls header (rev. 2)

2008-02-01T23:30:53Z

Move the definitions of hibernation ioctls to a separate header file in include/linux, which can be exported to the user space. Signed-off-by: Rafael J. Wysocki Acked-by: Pavel Machek Signed-off-by: Len Brown

Hibernation: Correct definitions of some ioctls (rev. 2)

2008-02-01T23:30:53Z

Three ioctl numbers belonging to the hibernation userland interface, SNAPSHOT_ATOMIC_SNAPSHOT, SNAPSHOT_AVAIL_SWAP, SNAPSHOT_GET_SWAP_PAGE, are defined in a wrong way (eg. not portable). Provide new ioctl numbers for these ioctls and mark the existing ones as deprecated. Signed-off-by: Rafael J. Wysocki Acked-by: Pavel Machek Signed-off-by: Len Brown

Hibernation: Mark SNAPSHOT_SET_SWAP_FILE ioctl as deprecated (rev. 2)

2008-02-01T23:30:53Z

Mark the SNAPSHOT_SET_SWAP_FILE ioctl belonging to the hibernation userland interface as deprecated. Signed-off-by: Rafael J. Wysocki Acked-by: Pavel Machek Signed-off-by: Len Brown