kernel/linux.git/include/linux/suspend.h, branch linux-2.6.28.y

suspend: fix section mismatch warning - register_nosave_region

2008-08-15T15:35:42+00:00

WARNING: vmlinux.o(.text+0xe684): Section mismatch in reference from the function register_nosave_region() to the function .init.text:__register_nosave_region() The function register_nosave_region() references the function __init __register_nosave_region(). This is often because register_nosave_region lacks a __init annotation or the annotation of __register_nosave_region is wrong. register_nosave_region calls __init function and is called only from __init functions Signed-off-by: Marcin Slusarz Acked-by: Rafael J. Wysocki Cc: Pavel Machek Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

kexec jump: save/restore device state

2008-07-26T19:00:04+00:00

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-related patches for 2.6.27

2008-06-12T21:25:09+00:00

ACPI PM: Add possibility to change suspend sequence There are some systems out there that don't work correctly with our current suspend/hibernation code ordering. Provide a workaround for these systems allowing them to pass 'acpi_sleep=old_ordering' in the kernel command line so that it will use the pre-ACPI 2.0 ("old") suspend code ordering. Unfortunately, this requires us to add a platform hook to the resuming of devices for recovering the platform in case one of the device drivers' .suspend() routines returns error code. Namely, ACPI 1.0 specifies that _PTS should be called before suspending devices, but _WAK still should be called before resuming them in order to undo the changes made by _PTS. However, if there is an error during suspending devices, they are automatically resumed without returning control to the PM core, so the _WAK has to be called from within device_resume() in that cases. The patch also reorders and refactors the ACPI suspend/hibernation code to avoid duplication as far as reasonably possible. Signed-off-by: Rafael J. Wysocki Acked-by: Pavel Machek Signed-off-by: Jesse Barnes

PM/gxfb: add hook to PM console layer that allows disabling of suspend VT switch

2008-04-28T15:58:36+00:00

Prior to suspend, we allocate and switch to a new VT; after suspend, we switch back to the original VT. This can be slow, and is completely unnecessary if the framebuffer we're using can restore video properly. This adds a hook that allows drivers to select whether or not to do this vt switch, and changes the gxfb driver to call this hook. It also adds a module param to gxfb to allow controlling of the vt switch (defaulting to no switch). (Note: I'm not convinced that console_sem is the best way to protect this, but we should probably have some form of locking..) [akpm@linux-foundation.org: build fix] Signed-off-by: Andres Salomon Cc: Jordan Crouse Cc: "Antonino A. Daplas" Cc: Pavel Machek Cc: "Rafael J. Wysocki" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Page allocator: clean up pcp draining functions

2008-02-05T17:44:17+00:00

- Add comments explaing how drain_pages() works. - Eliminate useless functions - Rename drain_all_local_pages to drain_all_pages(). It does drain all pages not only those of the local processor. - Eliminate useless interrupt off / on sequences. drain_pages() disables interrupts on its own. The execution thread is pinned to processor by the caller. So there is no need to disable interrupts. - Put drain_all_pages() declaration in gfp.h and remove the declarations from suspend.h and from mm/memory_hotplug.c - Make software suspend call drain_all_pages(). The draining of processor local pages is may not the right approach if software suspend wants to support SMP. If they call drain_all_pages then we can make drain_pages() static. [akpm@linux-foundation.org: fix build] Signed-off-by: Christoph Lameter Acked-by: Mel Gorman Cc: "Rafael J. Wysocki" Cc: Daniel Walker Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Hibernation: Introduce begin() and end() callbacks

2008-02-01T23:30:58+00:00

Introduce global hibernation callback .end() and rename global hibernation callback .start() to .begin(), in analogy with the recent modifications of the global suspend callbacks. Signed-off-by: Rafael J. Wysocki Signed-off-by: Len Brown

Suspend: Introduce begin() and end() callbacks

2008-02-01T23:30:56+00:00

On ACPI systems the target state set by acpi_pm_set_target() is reset by acpi_pm_finish(), but that need not be called if the suspend fails. All platforms that use the .set_target() global suspend callback are affected by analogous issues. For this reason, we need an additional global suspend callback that will reset the target state regardless of whether or not the suspend is successful. Also, it is reasonable to rename the .set_target() callback, since it will be used for a different purpose on ACPI systems (due to ACPI 1.0x code ordering requirements). Introduce the global suspend callback .end() to be executed at the end of the suspend sequence and rename the .set_target() global suspend callback to .begin(). Signed-off-by: Rafael J. Wysocki Signed-off-by: Len Brown

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

2008-02-01T23:30:54+00:00

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

x86: make __{save,restore}_processor_state static

2008-01-30T12:31:23+00:00

.. allowing to remove their declarations from a global include file (the symbols don't exist for anything but x86). Likewise for 64-bits' fix_processor_context(), just that that one was properly declared in an arch-specific header. Signed-off-by: Jan Beulich Signed-off-by: Ingo Molnar Signed-off-by: Thomas Gleixner

Hibernation: Check if ACPI is enabled during restore in the right place

2007-10-18T21:37:20+00:00

The following scenario leads to total confusion of the platform firmware on some boxes (eg. HPC nx6325): * Hibernate with ACPI enabled * Resume passing "acpi=off" to the boot kernel To prevent this from happening it's necessary to check if ACPI is enabled (and enable it if that's not the case) _right_ _after_ control has been transfered from the boot kernel to the image kernel, before device_power_up() is called (ie. with interrupts disabled). Enabling ACPI after calling device_power_up() turns out to be insufficient. For this reason, introduce new hibernation callback ->leave() that will be executed before device_power_up() by the restored image kernel. To make it work, it also is necessary to move swsusp_suspend() from swsusp.c to disk.c (it's name is changed to "create_image", which is more up to the point). Signed-off-by: Rafael J. Wysocki Acked-by: Pavel Machek Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds