From f577eb30afdc68233f25d4d82b04102129262365 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Thu, 23 Mar 2006 02:59:59 -0800 Subject: [PATCH] swsusp: low level interface Introduce the low level interface that can be used for handling the snapshot of the system memory by the in-kernel swap-writing/reading code of swsusp and the userland interface code (to be introduced shortly). Also change the way in which swsusp records the allocated swap pages and, consequently, simplifies the in-kernel swap-writing/reading code (this is necessary for the userland interface too). To this end, it introduces two helper functions in mm/swapfile.c, so that the swsusp code does not refer directly to the swap internals. Signed-off-by: Rafael J. Wysocki Acked-by: Pavel Machek Signed-off-by: Adrian Bunk Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/power/disk.c | 12 ++++-------- 1 file changed, 4 insertions(+), 8 deletions(-) (limited to 'kernel/power/disk.c') diff --git a/kernel/power/disk.c b/kernel/power/disk.c index 0b43847dc98..4eb464b7134 100644 --- a/kernel/power/disk.c +++ b/kernel/power/disk.c @@ -26,9 +26,9 @@ extern suspend_disk_method_t pm_disk_mode; extern int swsusp_shrink_memory(void); extern int swsusp_suspend(void); -extern int swsusp_write(struct pbe *pblist, unsigned int nr_pages); +extern int swsusp_write(void); extern int swsusp_check(void); -extern int swsusp_read(struct pbe **pblist_ptr); +extern int swsusp_read(void); extern void swsusp_close(void); extern int swsusp_resume(void); @@ -70,10 +70,6 @@ static void power_down(suspend_disk_method_t mode) while(1); } - -static int in_suspend __nosavedata = 0; - - static inline void platform_finish(void) { if (pm_disk_mode == PM_DISK_PLATFORM) { @@ -145,7 +141,7 @@ int pm_suspend_disk(void) if (in_suspend) { device_resume(); pr_debug("PM: writing image.\n"); - error = swsusp_write(pagedir_nosave, nr_copy_pages); + error = swsusp_write(); if (!error) power_down(pm_disk_mode); else { @@ -216,7 +212,7 @@ static int software_resume(void) pr_debug("PM: Reading swsusp image.\n"); - if ((error = swsusp_read(&pagedir_nosave))) { + if ((error = swsusp_read())) { swsusp_free(); goto Thaw; } -- cgit v1.2.3-70-g09d2 From 74c7e2efbe37378026f00ad9e7253796d7b2fc99 Mon Sep 17 00:00:00 2001 From: Randy Dunlap Date: Thu, 23 Mar 2006 03:00:01 -0800 Subject: [PATCH] kernel/power: move externs to header files Move externs from C source files to header files. Signed-off-by: Randy Dunlap Cc: "Rafael J. Wysocki" Cc: Pavel Machek Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/pm.h | 3 ++- kernel/power/disk.c | 11 ----------- kernel/power/power.h | 6 +++++- 3 files changed, 7 insertions(+), 13 deletions(-) (limited to 'kernel/power/disk.c') diff --git a/include/linux/pm.h b/include/linux/pm.h index 5be87ba3b7a..6df2585c016 100644 --- a/include/linux/pm.h +++ b/include/linux/pm.h @@ -188,6 +188,8 @@ extern void device_power_up(void); extern void device_resume(void); #ifdef CONFIG_PM +extern suspend_disk_method_t pm_disk_mode; + extern int device_suspend(pm_message_t state); #define device_set_wakeup_enable(dev,val) \ @@ -215,7 +217,6 @@ static inline int dpm_runtime_suspend(struct device * dev, pm_message_t state) static inline void dpm_runtime_resume(struct device * dev) { - } #endif diff --git a/kernel/power/disk.c b/kernel/power/disk.c index 4eb464b7134..4bd68f482f2 100644 --- a/kernel/power/disk.c +++ b/kernel/power/disk.c @@ -22,17 +22,6 @@ #include "power.h" -extern suspend_disk_method_t pm_disk_mode; - -extern int swsusp_shrink_memory(void); -extern int swsusp_suspend(void); -extern int swsusp_write(void); -extern int swsusp_check(void); -extern int swsusp_read(void); -extern void swsusp_close(void); -extern int swsusp_resume(void); - - static int noresume = 0; char resume_file[256] = CONFIG_PM_STD_PARTITION; dev_t swsusp_resume_device; diff --git a/kernel/power/power.h b/kernel/power/power.h index 089c84bed89..5d1abffbb9c 100644 --- a/kernel/power/power.h +++ b/kernel/power/power.h @@ -48,7 +48,6 @@ extern asmlinkage int swsusp_arch_suspend(void); extern asmlinkage int swsusp_arch_resume(void); extern unsigned int count_data_pages(void); -extern void swsusp_free(void); struct snapshot_handle { loff_t offset; @@ -91,6 +90,11 @@ extern struct bitmap_page *alloc_bitmap(unsigned int nr_bits); extern unsigned long alloc_swap_page(int swap, struct bitmap_page *bitmap); extern void free_all_swap_pages(int swap, struct bitmap_page *bitmap); +extern int swsusp_check(void); extern int swsusp_shrink_memory(void); +extern void swsusp_free(void); extern int swsusp_suspend(void); extern int swsusp_resume(void); +extern int swsusp_read(void); +extern int swsusp_write(void); +extern void swsusp_close(void); -- cgit v1.2.3-70-g09d2 From 02aaeb9b952f30b1ad6284d5d45be02030f679db Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Thu, 23 Mar 2006 03:00:04 -0800 Subject: [PATCH] swsusp: freeze user space processes first Allow swsusp to freeze processes successfully under heavy load by freezing userspace processes before kernel threads. [Thanks to Nigel Cunningham for suggesting the way to go.] Signed-off-by: Rafael J. Wysocki Acked-by: Pavel Machek Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/power/disk.c | 1 - kernel/power/process.c | 61 +++++++++++++++++++++++++++++++++++++------------- kernel/power/user.c | 1 - 3 files changed, 46 insertions(+), 17 deletions(-) (limited to 'kernel/power/disk.c') diff --git a/kernel/power/disk.c b/kernel/power/disk.c index 4bd68f482f2..81d4d982f3f 100644 --- a/kernel/power/disk.c +++ b/kernel/power/disk.c @@ -72,7 +72,6 @@ static int prepare_processes(void) int error; pm_prepare_console(); - sys_sync(); disable_nonboot_cpus(); if (freeze_processes()) { diff --git a/kernel/power/process.c b/kernel/power/process.c index 02a1b3a9fa9..8ac7c35fad7 100644 --- a/kernel/power/process.c +++ b/kernel/power/process.c @@ -12,11 +12,12 @@ #include #include #include +#include /* * Timeout for stopping processes */ -#define TIMEOUT (6 * HZ) +#define TIMEOUT (20 * HZ) static inline int freezeable(struct task_struct * p) @@ -54,38 +55,62 @@ void refrigerator(void) current->state = save; } +static inline void freeze_process(struct task_struct *p) +{ + unsigned long flags; + + if (!freezing(p)) { + freeze(p); + spin_lock_irqsave(&p->sighand->siglock, flags); + signal_wake_up(p, 0); + spin_unlock_irqrestore(&p->sighand->siglock, flags); + } +} + /* 0 = success, else # of processes that we failed to stop */ int freeze_processes(void) { - int todo; + int todo, nr_user, user_frozen; unsigned long start_time; struct task_struct *g, *p; unsigned long flags; printk( "Stopping tasks: " ); start_time = jiffies; + user_frozen = 0; do { - todo = 0; + nr_user = todo = 0; read_lock(&tasklist_lock); do_each_thread(g, p) { if (!freezeable(p)) continue; if (frozen(p)) continue; - - freeze(p); - spin_lock_irqsave(&p->sighand->siglock, flags); - signal_wake_up(p, 0); - spin_unlock_irqrestore(&p->sighand->siglock, flags); - todo++; + if (p->mm && !(p->flags & PF_BORROWED_MM)) { + /* The task is a user-space one. + * Freeze it unless there's a vfork completion + * pending + */ + if (!p->vfork_done) + freeze_process(p); + nr_user++; + } else { + /* Freeze only if the user space is frozen */ + if (user_frozen) + freeze_process(p); + todo++; + } } while_each_thread(g, p); read_unlock(&tasklist_lock); + todo += nr_user; + if (!user_frozen && !nr_user) { + sys_sync(); + start_time = jiffies; + } + user_frozen = !nr_user; yield(); /* Yield is okay here */ - if (todo && time_after(jiffies, start_time + TIMEOUT)) { - printk( "\n" ); - printk(KERN_ERR " stopping tasks timed out (%d tasks remaining)\n", todo ); + if (todo && time_after(jiffies, start_time + TIMEOUT)) break; - } } while(todo); /* This does not unfreeze processes that are already frozen @@ -94,8 +119,14 @@ int freeze_processes(void) * but it cleans up leftover PF_FREEZE requests. */ if (todo) { + printk( "\n" ); + printk(KERN_ERR " stopping tasks timed out " + "after %d seconds (%d tasks remaining):\n", + TIMEOUT / HZ, todo); read_lock(&tasklist_lock); - do_each_thread(g, p) + do_each_thread(g, p) { + if (freezeable(p) && !frozen(p)) + printk(KERN_ERR " %s\n", p->comm); if (freezing(p)) { pr_debug(" clean up: %s\n", p->comm); p->flags &= ~PF_FREEZE; @@ -103,7 +134,7 @@ int freeze_processes(void) recalc_sigpending_tsk(p); spin_unlock_irqrestore(&p->sighand->siglock, flags); } - while_each_thread(g, p); + } while_each_thread(g, p); read_unlock(&tasklist_lock); return todo; } diff --git a/kernel/power/user.c b/kernel/power/user.c index 8cabc405ca1..a97406b86ef 100644 --- a/kernel/power/user.c +++ b/kernel/power/user.c @@ -138,7 +138,6 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp, case SNAPSHOT_FREEZE: if (data->frozen) break; - sys_sync(); down(&pm_sem); pm_prepare_console(); disable_nonboot_cpus(); -- cgit v1.2.3-70-g09d2