From: Michael Holzheu <holzheu at linux.vnet.ibm.com> This patch is a suggestion to solve the issue reported by Ursula Braun: https://lists.linux-foundation.org/pipermail/linux-pm/2009-March/020443.html On s390 we have device drivers that don't belong to a Linux bus. Therefore we can't use the PM device callbacks (dev_pm_ops). The only way to get informed that we hibernate or resume is the pm_notifier_call_chain. Unfortunately some of our drivers need a frozen userspace to do their hibernate actions and the current notifiers are called before userspace is frozen. Another point is that we want our console driver to suspend as late as possible so that we can see all the hibernate progress messages on the console. This patch introduces the following new events for the pm_notifier: * PM_HIBERNATION_PREPARE_FROZEN: Going to hibernate. Processes are frozen. * PM_POST_HIBERNATION_FROZEN: Hibernation finished. Processes are frozen. * PM_RESTORE_PREPARE_FROZEN: Going to restore a saved image. Processes are frozen. * PM_POST_RESTORE_FROZEN: Restore failed. Processes are frozen. Signed-off-by: Michael Holzheu <holzheu at linux.vnet.ibm.com> --- include/linux/notifier.h | 8 ++++++++ kernel/power/disk.c | 34 +++++++++++++++++++++------------- 2 files changed, 29 insertions(+), 13 deletions(-) Index: git-linux-2.6-defconfig/include/linux/notifier.h =================================================================== --- git-linux-2.6-defconfig.orig/include/linux/notifier.h +++ git-linux-2.6-defconfig/include/linux/notifier.h @@ -245,6 +245,14 @@ static inline int notifier_to_errno(int #define PM_POST_SUSPEND 0x0004 /* Suspend finished */ #define PM_RESTORE_PREPARE 0x0005 /* Going to restore a saved image */ #define PM_POST_RESTORE 0x0006 /* Restore failed */ +#define PM_HIBERNATION_PREPARE_FROZEN 0x0007 /* Going to hibernate. Processes + * are frozen. */ +#define PM_POST_HIBERNATION_FROZEN 0x0008 /* Hibernation finished. + * Processes are frozen. */ +#define PM_RESTORE_PREPARE_FROZEN 0x0009 /* Going to restore a saved + * image. Processes are frozen.*/ +#define PM_POST_RESTORE_FROZEN 0x0010 /* Restore failed. Processes are + * frozen. */ /* Console keyboard events. * Note: KBD_KEYCODE is always sent before KBD_UNBOUND_KEYCODE, KBD_UNICODE and Index: git-linux-2.6-defconfig/kernel/power/disk.c =================================================================== --- git-linux-2.6-defconfig.orig/kernel/power/disk.c +++ git-linux-2.6-defconfig/kernel/power/disk.c @@ -309,15 +309,21 @@ int hibernation_snapshot(int platform_mo suspend_console(); error = device_suspend(PMSG_FREEZE); - if (error) - goto Recover_platform; - - if (hibernation_test(TEST_DEVICES)) - goto Recover_platform; + if (error) { + platform_recover(platform_mode); + goto Resume_devices; + } + error = pm_notifier_call_chain(PM_HIBERNATION_PREPARE_FROZEN); + if (error || hibernation_test(TEST_DEVICES)) { + pm_notifier_call_chain(PM_POST_HIBERNATION_FROZEN); + platform_recover(platform_mode); + goto Resume_devices; + } error = create_image(platform_mode); /* Control returns here after successful restore */ + pm_notifier_call_chain(PM_POST_HIBERNATION_FROZEN); Resume_devices: device_resume(in_suspend ? (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE); @@ -325,10 +331,6 @@ int hibernation_snapshot(int platform_mo Close: platform_end(platform_mode); return error; - - Recover_platform: - platform_recover(platform_mode); - goto Resume_devices; } /** @@ -424,10 +426,16 @@ int hibernation_restore(int platform_mod pm_prepare_console(); suspend_console(); error = device_suspend(PMSG_QUIESCE); - if (!error) { - error = resume_target_kernel(platform_mode); - device_resume(PMSG_RECOVER); - } + if (error) + goto Resume_console; + error = pm_notifier_call_chain(PM_RESTORE_PREPARE_FROZEN); + if (error) + goto Notifier_call_chain; + error = resume_target_kernel(platform_mode); + device_resume(PMSG_RECOVER); + Notifier_call_chain: + pm_notifier_call_chain(PM_POST_RESTORE_FROZEN); + Resume_console: resume_console(); pm_restore_console(); return error; _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
