* [PATCH -mm 1/2] Separate freezer from PM code (rev. 2)
2007-04-28 9:35 [PATCH -mm 0/2] Separate freezer from PM code (take 2) Rafael J. Wysocki
@ 2007-04-28 9:37 ` Rafael J. Wysocki
2007-04-28 20:47 ` Pavel Machek
2007-04-28 9:40 ` [PATCH -mm 2/2] Introduce freezer flags " Rafael J. Wysocki
1 sibling, 1 reply; 5+ messages in thread
From: Rafael J. Wysocki @ 2007-04-28 9:37 UTC (permalink / raw)
To: Andrew Morton
Cc: Gautham R Shenoy, Ingo Molnar, Oleg Nesterov, Pavel Machek,
Pekka Enberg, LKML
From: Rafael J. Wysocki <rjw@sisk.pl>
Now that the freezer is used by kprobes, it is no longer a PM-specific piece of
code. Move the freezer code out of kernel/power and introduce the
CONFIG_FREEZER option that will be chosen automatically if PM or KPROBES is
set.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
---
arch/arm/Kconfig | 2
arch/avr32/Kconfig | 2
arch/avr32/Kconfig.debug | 1
arch/blackfin/Kconfig | 2
arch/frv/Kconfig | 2
arch/i386/Kconfig | 3
arch/ia64/Kconfig | 3
arch/mips/Kconfig | 2
arch/powerpc/Kconfig | 3
arch/ppc/Kconfig | 2
arch/s390/Kconfig | 3
arch/sh/Kconfig | 2
arch/sparc64/Kconfig | 3
arch/x86_64/Kconfig | 3
include/linux/freezer.h | 2
kernel/Kconfig.freezer | 5
kernel/Makefile | 1
kernel/freezer.c | 236 +++++++++++++++++++++++++++++++++++++++++++++++
kernel/kprobes.c | 2
kernel/power/Kconfig | 1
kernel/power/Makefile | 2
kernel/power/process.c | 236 -----------------------------------------------
22 files changed, 279 insertions(+), 239 deletions(-)
Index: linux-2.6.21-rc7-mm2/arch/x86_64/Kconfig
===================================================================
--- linux-2.6.21-rc7-mm2.orig/arch/x86_64/Kconfig 2007-04-27 21:41:05.000000000 +0200
+++ linux-2.6.21-rc7-mm2/arch/x86_64/Kconfig 2007-04-27 23:20:43.000000000 +0200
@@ -703,6 +703,8 @@ config GENERIC_PENDING_IRQ
depends on GENERIC_HARDIRQS && SMP
default y
+source "kernel/Kconfig.freezer"
+
menu "Power management options"
source kernel/power/Kconfig
@@ -791,6 +793,7 @@ source "arch/x86_64/oprofile/Kconfig"
config KPROBES
bool "Kprobes (EXPERIMENTAL)"
depends on KALLSYMS && EXPERIMENTAL && MODULES
+ select FREEZER
help
Kprobes allows you to trap at almost any kernel address and
execute a callback function. register_kprobe() establishes
Index: linux-2.6.21-rc7-mm2/arch/avr32/Kconfig.debug
===================================================================
--- linux-2.6.21-rc7-mm2.orig/arch/avr32/Kconfig.debug 2007-04-27 21:41:05.000000000 +0200
+++ linux-2.6.21-rc7-mm2/arch/avr32/Kconfig.debug 2007-04-27 21:54:19.000000000 +0200
@@ -12,6 +12,7 @@ menu "Instrumentation Support"
config KPROBES
bool "Kprobes"
depends on DEBUG_KERNEL
+ select FREEZER
help
Kprobes allows you to trap at almost any kernel address and
execute a callback function. register_kprobe() establishes
Index: linux-2.6.21-rc7-mm2/arch/frv/Kconfig
===================================================================
--- linux-2.6.21-rc7-mm2.orig/arch/frv/Kconfig 2007-04-27 21:41:05.000000000 +0200
+++ linux-2.6.21-rc7-mm2/arch/frv/Kconfig 2007-04-27 23:13:27.000000000 +0200
@@ -364,6 +364,8 @@ source "drivers/pcmcia/Kconfig"
# sleep-deprived psychotic hacker types can say Y now, everyone else
# should probably wait a while.
+source "kernel/Kconfig.freezer"
+
menu "Power management options"
source kernel/power/Kconfig
endmenu
Index: linux-2.6.21-rc7-mm2/arch/i386/Kconfig
===================================================================
--- linux-2.6.21-rc7-mm2.orig/arch/i386/Kconfig 2007-04-27 21:41:05.000000000 +0200
+++ linux-2.6.21-rc7-mm2/arch/i386/Kconfig 2007-04-27 23:17:36.000000000 +0200
@@ -912,6 +912,8 @@ config ARCH_ENABLE_MEMORY_HOTPLUG
def_bool y
depends on HIGHMEM
+source "kernel/Kconfig.freezer"
+
menu "Power management options (ACPI, APM)"
depends on !X86_VOYAGER
@@ -1218,6 +1220,7 @@ source "arch/i386/oprofile/Kconfig"
config KPROBES
bool "Kprobes (EXPERIMENTAL)"
depends on KALLSYMS && EXPERIMENTAL && MODULES
+ select FREEZER
help
Kprobes allows you to trap at almost any kernel address and
execute a callback function. register_kprobe() establishes
Index: linux-2.6.21-rc7-mm2/arch/ia64/Kconfig
===================================================================
--- linux-2.6.21-rc7-mm2.orig/arch/ia64/Kconfig 2007-04-27 21:41:05.000000000 +0200
+++ linux-2.6.21-rc7-mm2/arch/ia64/Kconfig 2007-04-27 23:21:40.000000000 +0200
@@ -495,6 +495,8 @@ source "fs/Kconfig.binfmt"
endmenu
+source "kernel/Kconfig.freezer"
+
menu "Power management and ACPI"
source "kernel/power/Kconfig"
@@ -582,6 +584,7 @@ source "arch/ia64/oprofile/Kconfig"
config KPROBES
bool "Kprobes (EXPERIMENTAL)"
depends on KALLSYMS && EXPERIMENTAL && MODULES
+ select FREEZER
help
Kprobes allows you to trap at almost any kernel address and
execute a callback function. register_kprobe() establishes
Index: linux-2.6.21-rc7-mm2/arch/powerpc/Kconfig
===================================================================
--- linux-2.6.21-rc7-mm2.orig/arch/powerpc/Kconfig 2007-04-27 21:41:05.000000000 +0200
+++ linux-2.6.21-rc7-mm2/arch/powerpc/Kconfig 2007-04-27 23:15:12.000000000 +0200
@@ -552,6 +552,8 @@ config CMDLINE
some command-line options at build time by entering them here. In
most cases you will need to specify the root device here.
+source kernel/Kconfig.freezer
+
if !44x || BROKEN
source kernel/power/Kconfig
endif
@@ -865,6 +867,7 @@ source "arch/powerpc/oprofile/Kconfig"
config KPROBES
bool "Kprobes (EXPERIMENTAL)"
depends on !BOOKE && !4xx && KALLSYMS && EXPERIMENTAL && MODULES
+ select FREEZER
help
Kprobes allows you to trap at almost any kernel address and
execute a callback function. register_kprobe() establishes
Index: linux-2.6.21-rc7-mm2/arch/ppc/Kconfig
===================================================================
--- linux-2.6.21-rc7-mm2.orig/arch/ppc/Kconfig 2007-04-27 21:41:05.000000000 +0200
+++ linux-2.6.21-rc7-mm2/arch/ppc/Kconfig 2007-04-27 23:15:25.000000000 +0200
@@ -1153,6 +1153,8 @@ config PROC_HARDWARE
source "drivers/zorro/Kconfig"
+source "kernel/Kconfig.freezer"
+
if !44x || BROKEN
source kernel/power/Kconfig
endif
Index: linux-2.6.21-rc7-mm2/arch/s390/Kconfig
===================================================================
--- linux-2.6.21-rc7-mm2.orig/arch/s390/Kconfig 2007-04-27 21:41:05.000000000 +0200
+++ linux-2.6.21-rc7-mm2/arch/s390/Kconfig 2007-04-27 23:23:19.000000000 +0200
@@ -550,6 +550,8 @@ source "drivers/net/Kconfig"
source "fs/Kconfig"
+source "kernel/Kconfig.freezer"
+
menu "Instrumentation Support"
source "arch/s390/oprofile/Kconfig"
@@ -557,6 +559,7 @@ source "arch/s390/oprofile/Kconfig"
config KPROBES
bool "Kprobes (EXPERIMENTAL)"
depends on EXPERIMENTAL && MODULES
+ select FREEZER
help
Kprobes allows you to trap at almost any kernel address and
execute a callback function. register_kprobe() establishes
Index: linux-2.6.21-rc7-mm2/arch/sh/Kconfig
===================================================================
--- linux-2.6.21-rc7-mm2.orig/arch/sh/Kconfig 2007-04-27 21:41:05.000000000 +0200
+++ linux-2.6.21-rc7-mm2/arch/sh/Kconfig 2007-04-27 23:23:33.000000000 +0200
@@ -699,6 +699,8 @@ source "fs/Kconfig.binfmt"
endmenu
+source "kernel/Kconfig.freezer"
+
menu "Power management options (EXPERIMENTAL)"
depends on EXPERIMENTAL
Index: linux-2.6.21-rc7-mm2/arch/sparc64/Kconfig
===================================================================
--- linux-2.6.21-rc7-mm2.orig/arch/sparc64/Kconfig 2007-04-27 21:41:05.000000000 +0200
+++ linux-2.6.21-rc7-mm2/arch/sparc64/Kconfig 2007-04-27 23:23:44.000000000 +0200
@@ -420,6 +420,8 @@ source "drivers/fc4/Kconfig"
source "fs/Kconfig"
+source "kernel/Kconfig.freezer"
+
menu "Instrumentation Support"
depends on EXPERIMENTAL
@@ -428,6 +430,7 @@ source "arch/sparc64/oprofile/Kconfig"
config KPROBES
bool "Kprobes (EXPERIMENTAL)"
depends on KALLSYMS && EXPERIMENTAL && MODULES
+ select FREEZER
help
Kprobes allows you to trap at almost any kernel address and
execute a callback function. register_kprobe() establishes
Index: linux-2.6.21-rc7-mm2/kernel/Makefile
===================================================================
--- linux-2.6.21-rc7-mm2.orig/kernel/Makefile 2007-04-27 21:41:05.000000000 +0200
+++ linux-2.6.21-rc7-mm2/kernel/Makefile 2007-04-27 21:41:28.000000000 +0200
@@ -33,6 +33,7 @@ obj-$(CONFIG_MODULES) += module.o
obj-$(CONFIG_KALLSYMS) += kallsyms.o
obj-$(CONFIG_STACK_UNWIND) += unwind.o
obj-$(CONFIG_PM) += power/
+obj-$(CONFIG_FREEZER) += freezer.o
obj-$(CONFIG_BSD_PROCESS_ACCT) += acct.o
obj-$(CONFIG_KEXEC) += kexec.o
obj-$(CONFIG_COMPAT) += compat.o
Index: linux-2.6.21-rc7-mm2/kernel/power/Makefile
===================================================================
--- linux-2.6.21-rc7-mm2.orig/kernel/power/Makefile 2007-04-27 21:41:05.000000000 +0200
+++ linux-2.6.21-rc7-mm2/kernel/power/Makefile 2007-04-27 21:41:28.000000000 +0200
@@ -3,7 +3,7 @@ ifeq ($(CONFIG_PM_DEBUG),y)
EXTRA_CFLAGS += -DDEBUG
endif
-obj-y := main.o process.o console.o notify.o
+obj-y := main.o console.o notify.o
obj-$(CONFIG_PM_LEGACY) += pm.o
obj-$(CONFIG_SOFTWARE_SUSPEND) += swsusp.o disk.o snapshot.o swap.o user.o
Index: linux-2.6.21-rc7-mm2/kernel/kprobes.c
===================================================================
--- linux-2.6.21-rc7-mm2.orig/kernel/kprobes.c 2007-04-27 21:41:05.000000000 +0200
+++ linux-2.6.21-rc7-mm2/kernel/kprobes.c 2007-04-27 21:41:28.000000000 +0200
@@ -108,7 +108,7 @@ static int collect_garbage_slots(void);
static int __kprobes check_safety(void)
{
int ret = 0;
-#if defined(CONFIG_PREEMPT) && defined(CONFIG_PM)
+#ifdef CONFIG_PREEMPT
ret = freeze_processes();
if (ret == 0) {
struct task_struct *p, *q;
Index: linux-2.6.21-rc7-mm2/include/linux/freezer.h
===================================================================
--- linux-2.6.21-rc7-mm2.orig/include/linux/freezer.h 2007-04-27 21:41:27.000000000 +0200
+++ linux-2.6.21-rc7-mm2/include/linux/freezer.h 2007-04-27 23:20:23.000000000 +0200
@@ -2,7 +2,7 @@
#include <linux/sched.h>
-#ifdef CONFIG_PM
+#ifdef CONFIG_FREEZER
/*
* Check if a process has been frozen
*/
Index: linux-2.6.21-rc7-mm2/arch/arm/Kconfig
===================================================================
--- linux-2.6.21-rc7-mm2.orig/arch/arm/Kconfig 2007-04-27 21:41:05.000000000 +0200
+++ linux-2.6.21-rc7-mm2/arch/arm/Kconfig 2007-04-27 23:11:10.000000000 +0200
@@ -925,6 +925,8 @@ config ARTHUR
endmenu
+source "kernel/Kconfig.freezer"
+
menu "Power management options"
source "kernel/power/Kconfig"
Index: linux-2.6.21-rc7-mm2/arch/blackfin/Kconfig
===================================================================
--- linux-2.6.21-rc7-mm2.orig/arch/blackfin/Kconfig 2007-04-27 21:41:05.000000000 +0200
+++ linux-2.6.21-rc7-mm2/arch/blackfin/Kconfig 2007-04-27 23:13:09.000000000 +0200
@@ -816,6 +816,8 @@ source "fs/Kconfig.binfmt"
endmenu
+source "kernel/Kconfig.freezer"
+
menu "Power management options"
source "kernel/power/Kconfig"
Index: linux-2.6.21-rc7-mm2/arch/mips/Kconfig
===================================================================
--- linux-2.6.21-rc7-mm2.orig/arch/mips/Kconfig 2007-04-27 21:41:05.000000000 +0200
+++ linux-2.6.21-rc7-mm2/arch/mips/Kconfig 2007-04-27 23:22:37.000000000 +0200
@@ -2067,6 +2067,8 @@ source "drivers/pci/hotplug/Kconfig"
endmenu
+source "kernel/Kconfig.freezer"
+
menu "Executable file formats"
source "fs/Kconfig.binfmt"
Index: linux-2.6.21-rc7-mm2/kernel/freezer.c
===================================================================
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ linux-2.6.21-rc7-mm2/kernel/freezer.c 2007-04-27 23:20:23.000000000 +0200
@@ -0,0 +1,236 @@
+/*
+ * linux/kernel/freezer.c
+ *
+ * Generic mechanism for freezing and thawing tasks, originally from swsusp.
+ *
+ * Distributed under the GPLv2
+ */
+
+
+#undef DEBUG
+
+#include <linux/sched.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/syscalls.h>
+#include <linux/freezer.h>
+
+/*
+ * Timeout for stopping processes
+ */
+#define TIMEOUT (20 * HZ)
+
+#define FREEZER_KERNEL_THREADS 0
+#define FREEZER_USER_SPACE 1
+
+static inline int freezeable(struct task_struct * p)
+{
+ if ((p == current) ||
+ (p->flags & PF_NOFREEZE) ||
+ (p->exit_state != 0))
+ return 0;
+ return 1;
+}
+
+/*
+ * freezing is complete, mark current process as frozen
+ */
+static inline void frozen_process(void)
+{
+ if (!unlikely(current->flags & PF_NOFREEZE)) {
+ current->flags |= PF_FROZEN;
+ wmb();
+ }
+ clear_tsk_thread_flag(current, TIF_FREEZE);
+}
+
+/* Refrigerator is place where frozen processes are stored :-). */
+void refrigerator(void)
+{
+ /* Hmm, should we be allowed to suspend when there are realtime
+ processes around? */
+ long save;
+
+ task_lock(current);
+ if (freezing(current)) {
+ frozen_process();
+ task_unlock(current);
+ } else {
+ task_unlock(current);
+ return;
+ }
+ save = current->state;
+ pr_debug("%s entered refrigerator\n", current->comm);
+
+ spin_lock_irq(¤t->sighand->siglock);
+ recalc_sigpending(); /* We sent fake signal, clean it up */
+ spin_unlock_irq(¤t->sighand->siglock);
+
+ for (;;) {
+ set_current_state(TASK_UNINTERRUPTIBLE);
+ if (!frozen(current))
+ break;
+ schedule();
+ }
+ pr_debug("%s left refrigerator\n", current->comm);
+ current->state = save;
+}
+
+static inline void freeze_process(struct task_struct *p)
+{
+ unsigned long flags;
+
+ if (!freezing(p)) {
+ rmb();
+ if (!frozen(p)) {
+ if (p->state == TASK_STOPPED)
+ force_sig_specific(SIGSTOP, p);
+
+ freeze(p);
+ spin_lock_irqsave(&p->sighand->siglock, flags);
+ signal_wake_up(p, p->state == TASK_STOPPED);
+ spin_unlock_irqrestore(&p->sighand->siglock, flags);
+ }
+ }
+}
+
+static void cancel_freezing(struct task_struct *p)
+{
+ unsigned long flags;
+
+ if (freezing(p)) {
+ pr_debug(" clean up: %s\n", p->comm);
+ do_not_freeze(p);
+ spin_lock_irqsave(&p->sighand->siglock, flags);
+ recalc_sigpending_tsk(p);
+ spin_unlock_irqrestore(&p->sighand->siglock, flags);
+ }
+}
+
+static inline int is_user_space(struct task_struct *p)
+{
+ int ret;
+
+ task_lock(p);
+ ret = p->mm && !(p->flags & PF_BORROWED_MM);
+ task_unlock(p);
+ return ret;
+}
+
+static unsigned int try_to_freeze_tasks(int freeze_user_space)
+{
+ struct task_struct *g, *p;
+ unsigned long end_time;
+ unsigned int todo;
+
+ end_time = jiffies + TIMEOUT;
+ do {
+ todo = 0;
+ read_lock(&tasklist_lock);
+ do_each_thread(g, p) {
+ if (!freezeable(p))
+ continue;
+
+ if (frozen(p))
+ continue;
+
+ if (p->state == TASK_TRACED && frozen(p->parent)) {
+ cancel_freezing(p);
+ continue;
+ }
+ if (freeze_user_space && !is_user_space(p))
+ continue;
+
+ freeze_process(p);
+ if (!freezer_should_skip(p))
+ todo++;
+ } while_each_thread(g, p);
+ read_unlock(&tasklist_lock);
+ yield(); /* Yield is okay here */
+ if (todo && time_after(jiffies, end_time))
+ break;
+ } while (todo);
+
+ if (todo) {
+ /* This does not unfreeze processes that are already frozen
+ * (we have slightly ugly calling convention in that respect,
+ * and caller must call thaw_processes() if something fails),
+ * but it cleans up leftover PF_FREEZE requests.
+ */
+ printk("\n");
+ printk(KERN_ERR "Stopping %s timed out after %d seconds "
+ "(%d tasks refusing to freeze):\n",
+ freeze_user_space ? "user space processes" :
+ "kernel threads",
+ TIMEOUT / HZ, todo);
+ read_lock(&tasklist_lock);
+ do_each_thread(g, p) {
+ if (freeze_user_space && !is_user_space(p))
+ continue;
+
+ task_lock(p);
+ if (freezeable(p) && !frozen(p) &&
+ !freezer_should_skip(p))
+ printk(KERN_ERR " %s\n", p->comm);
+
+ cancel_freezing(p);
+ task_unlock(p);
+ } while_each_thread(g, p);
+ read_unlock(&tasklist_lock);
+ }
+
+ return todo;
+}
+
+/**
+ * freeze_processes - tell processes to enter the refrigerator
+ *
+ * Returns 0 on success, or the number of processes that didn't freeze,
+ * although they were told to.
+ */
+int freeze_processes(void)
+{
+ unsigned int nr_unfrozen;
+
+ printk("Stopping tasks ... ");
+ nr_unfrozen = try_to_freeze_tasks(FREEZER_USER_SPACE);
+ if (nr_unfrozen)
+ return nr_unfrozen;
+
+ sys_sync();
+ nr_unfrozen = try_to_freeze_tasks(FREEZER_KERNEL_THREADS);
+ if (nr_unfrozen)
+ return nr_unfrozen;
+
+ printk("done.\n");
+ BUG_ON(in_atomic());
+ return 0;
+}
+
+static void thaw_tasks(int thaw_user_space)
+{
+ struct task_struct *g, *p;
+
+ read_lock(&tasklist_lock);
+ do_each_thread(g, p) {
+ if (!freezeable(p))
+ continue;
+
+ if (is_user_space(p) == !thaw_user_space)
+ continue;
+
+ thaw_process(p);
+ } while_each_thread(g, p);
+ read_unlock(&tasklist_lock);
+}
+
+void thaw_processes(void)
+{
+ printk("Restarting tasks ... ");
+ thaw_tasks(FREEZER_KERNEL_THREADS);
+ thaw_tasks(FREEZER_USER_SPACE);
+ schedule();
+ printk("done.\n");
+}
+
+EXPORT_SYMBOL(refrigerator);
Index: linux-2.6.21-rc7-mm2/kernel/power/process.c
===================================================================
--- linux-2.6.21-rc7-mm2.orig/kernel/power/process.c 2007-04-27 21:41:27.000000000 +0200
+++ /dev/null 1970-01-01 00:00:00.000000000 +0000
@@ -1,236 +0,0 @@
-/*
- * drivers/power/process.c - Functions for starting/stopping processes on
- * suspend transitions.
- *
- * Originally from swsusp.
- */
-
-
-#undef DEBUG
-
-#include <linux/sched.h>
-#include <linux/interrupt.h>
-#include <linux/suspend.h>
-#include <linux/module.h>
-#include <linux/syscalls.h>
-#include <linux/freezer.h>
-
-/*
- * Timeout for stopping processes
- */
-#define TIMEOUT (20 * HZ)
-
-#define FREEZER_KERNEL_THREADS 0
-#define FREEZER_USER_SPACE 1
-
-static inline int freezeable(struct task_struct * p)
-{
- if ((p == current) ||
- (p->flags & PF_NOFREEZE) ||
- (p->exit_state != 0))
- return 0;
- return 1;
-}
-
-/*
- * freezing is complete, mark current process as frozen
- */
-static inline void frozen_process(void)
-{
- if (!unlikely(current->flags & PF_NOFREEZE)) {
- current->flags |= PF_FROZEN;
- wmb();
- }
- clear_tsk_thread_flag(current, TIF_FREEZE);
-}
-
-/* Refrigerator is place where frozen processes are stored :-). */
-void refrigerator(void)
-{
- /* Hmm, should we be allowed to suspend when there are realtime
- processes around? */
- long save;
-
- task_lock(current);
- if (freezing(current)) {
- frozen_process();
- task_unlock(current);
- } else {
- task_unlock(current);
- return;
- }
- save = current->state;
- pr_debug("%s entered refrigerator\n", current->comm);
-
- spin_lock_irq(¤t->sighand->siglock);
- recalc_sigpending(); /* We sent fake signal, clean it up */
- spin_unlock_irq(¤t->sighand->siglock);
-
- for (;;) {
- set_current_state(TASK_UNINTERRUPTIBLE);
- if (!frozen(current))
- break;
- schedule();
- }
- pr_debug("%s left refrigerator\n", current->comm);
- current->state = save;
-}
-
-static inline void freeze_process(struct task_struct *p)
-{
- unsigned long flags;
-
- if (!freezing(p)) {
- rmb();
- if (!frozen(p)) {
- if (p->state == TASK_STOPPED)
- force_sig_specific(SIGSTOP, p);
-
- freeze(p);
- spin_lock_irqsave(&p->sighand->siglock, flags);
- signal_wake_up(p, p->state == TASK_STOPPED);
- spin_unlock_irqrestore(&p->sighand->siglock, flags);
- }
- }
-}
-
-static void cancel_freezing(struct task_struct *p)
-{
- unsigned long flags;
-
- if (freezing(p)) {
- pr_debug(" clean up: %s\n", p->comm);
- do_not_freeze(p);
- spin_lock_irqsave(&p->sighand->siglock, flags);
- recalc_sigpending_tsk(p);
- spin_unlock_irqrestore(&p->sighand->siglock, flags);
- }
-}
-
-static inline int is_user_space(struct task_struct *p)
-{
- int ret;
-
- task_lock(p);
- ret = p->mm && !(p->flags & PF_BORROWED_MM);
- task_unlock(p);
- return ret;
-}
-
-static unsigned int try_to_freeze_tasks(int freeze_user_space)
-{
- struct task_struct *g, *p;
- unsigned long end_time;
- unsigned int todo;
-
- end_time = jiffies + TIMEOUT;
- do {
- todo = 0;
- read_lock(&tasklist_lock);
- do_each_thread(g, p) {
- if (!freezeable(p))
- continue;
-
- if (frozen(p))
- continue;
-
- if (p->state == TASK_TRACED && frozen(p->parent)) {
- cancel_freezing(p);
- continue;
- }
- if (freeze_user_space && !is_user_space(p))
- continue;
-
- freeze_process(p);
- if (!freezer_should_skip(p))
- todo++;
- } while_each_thread(g, p);
- read_unlock(&tasklist_lock);
- yield(); /* Yield is okay here */
- if (todo && time_after(jiffies, end_time))
- break;
- } while (todo);
-
- if (todo) {
- /* This does not unfreeze processes that are already frozen
- * (we have slightly ugly calling convention in that respect,
- * and caller must call thaw_processes() if something fails),
- * but it cleans up leftover PF_FREEZE requests.
- */
- printk("\n");
- printk(KERN_ERR "Stopping %s timed out after %d seconds "
- "(%d tasks refusing to freeze):\n",
- freeze_user_space ? "user space processes" :
- "kernel threads",
- TIMEOUT / HZ, todo);
- read_lock(&tasklist_lock);
- do_each_thread(g, p) {
- if (freeze_user_space && !is_user_space(p))
- continue;
-
- task_lock(p);
- if (freezeable(p) && !frozen(p) &&
- !freezer_should_skip(p))
- printk(KERN_ERR " %s\n", p->comm);
-
- cancel_freezing(p);
- task_unlock(p);
- } while_each_thread(g, p);
- read_unlock(&tasklist_lock);
- }
-
- return todo;
-}
-
-/**
- * freeze_processes - tell processes to enter the refrigerator
- *
- * Returns 0 on success, or the number of processes that didn't freeze,
- * although they were told to.
- */
-int freeze_processes(void)
-{
- unsigned int nr_unfrozen;
-
- printk("Stopping tasks ... ");
- nr_unfrozen = try_to_freeze_tasks(FREEZER_USER_SPACE);
- if (nr_unfrozen)
- return nr_unfrozen;
-
- sys_sync();
- nr_unfrozen = try_to_freeze_tasks(FREEZER_KERNEL_THREADS);
- if (nr_unfrozen)
- return nr_unfrozen;
-
- printk("done.\n");
- BUG_ON(in_atomic());
- return 0;
-}
-
-static void thaw_tasks(int thaw_user_space)
-{
- struct task_struct *g, *p;
-
- read_lock(&tasklist_lock);
- do_each_thread(g, p) {
- if (!freezeable(p))
- continue;
-
- if (is_user_space(p) == !thaw_user_space)
- continue;
-
- thaw_process(p);
- } while_each_thread(g, p);
- read_unlock(&tasklist_lock);
-}
-
-void thaw_processes(void)
-{
- printk("Restarting tasks ... ");
- thaw_tasks(FREEZER_KERNEL_THREADS);
- thaw_tasks(FREEZER_USER_SPACE);
- schedule();
- printk("done.\n");
-}
-
-EXPORT_SYMBOL(refrigerator);
Index: linux-2.6.21-rc7-mm2/arch/avr32/Kconfig
===================================================================
--- linux-2.6.21-rc7-mm2.orig/arch/avr32/Kconfig 2007-04-27 01:00:50.000000000 +0200
+++ linux-2.6.21-rc7-mm2/arch/avr32/Kconfig 2007-04-27 23:12:42.000000000 +0200
@@ -209,6 +209,8 @@ source "drivers/Kconfig"
source "fs/Kconfig"
+source "kernel/Kconfig.freezer"
+
source "arch/avr32/Kconfig.debug"
source "security/Kconfig"
Index: linux-2.6.21-rc7-mm2/kernel/power/Kconfig
===================================================================
--- linux-2.6.21-rc7-mm2.orig/kernel/power/Kconfig 2007-04-27 21:41:05.000000000 +0200
+++ linux-2.6.21-rc7-mm2/kernel/power/Kconfig 2007-04-27 21:42:52.000000000 +0200
@@ -1,6 +1,7 @@
config PM
bool "Power Management support"
depends on !IA64_HP_SIM
+ select FREEZER
---help---
"Power Management" means that parts of your computer are shut
off or put into a power conserving "sleep" mode if they are not
Index: linux-2.6.21-rc7-mm2/kernel/Kconfig.freezer
===================================================================
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ linux-2.6.21-rc7-mm2/kernel/Kconfig.freezer 2007-04-27 23:06:52.000000000 +0200
@@ -0,0 +1,5 @@
+# Tasks freezer configuration
+
+config FREEZER
+ bool
+ default n
^ permalink raw reply [flat|nested] 5+ messages in thread* [PATCH -mm 2/2] Introduce freezer flags (rev. 2)
2007-04-28 9:35 [PATCH -mm 0/2] Separate freezer from PM code (take 2) Rafael J. Wysocki
2007-04-28 9:37 ` [PATCH -mm 1/2] Separate freezer from PM code (rev. 2) Rafael J. Wysocki
@ 2007-04-28 9:40 ` Rafael J. Wysocki
2007-04-28 20:48 ` Pavel Machek
1 sibling, 1 reply; 5+ messages in thread
From: Rafael J. Wysocki @ 2007-04-28 9:40 UTC (permalink / raw)
To: Andrew Morton
Cc: Gautham R Shenoy, Ingo Molnar, Oleg Nesterov, Pavel Machek,
Pekka Enberg, LKML
From: Rafael J. Wysocki <rjw@sisk.pl>
Move all of the freezer-related flags to a separate field in task_struct and
introduce functions to operate them using set_bit() etc.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
---
Documentation/power/kernel_threads.txt | 2 -
Documentation/power/swsusp.txt | 4 +-
arch/i386/kernel/apm.c | 2 -
drivers/block/loop.c | 2 -
drivers/char/apm-emulation.c | 6 +--
drivers/ieee1394/ieee1394_core.c | 2 -
drivers/md/md.c | 2 -
drivers/mmc/card/queue.c | 3 +
drivers/mtd/mtd_blkdevs.c | 3 +
drivers/scsi/libsas/sas_scsi_host.c | 2 -
drivers/scsi/scsi_error.c | 2 -
drivers/usb/storage/usb.c | 2 -
include/asm-arm/thread_info.h | 2 -
include/asm-blackfin/thread_info.h | 2 -
include/asm-frv/thread_info.h | 2 -
include/asm-i386/thread_info.h | 2 -
include/asm-ia64/thread_info.h | 2 -
include/asm-mips/thread_info.h | 2 -
include/asm-powerpc/thread_info.h | 2 -
include/asm-sh/thread_info.h | 2 -
include/asm-x86_64/thread_info.h | 2 -
include/linux/freezer.h | 63 +++++++++++++++++++++++++++------
include/linux/sched.h | 8 ++--
kernel/fork.c | 5 ++
kernel/freezer.c | 10 ++---
kernel/kthread.c | 3 +
kernel/rcutorture.c | 4 +-
kernel/sched.c | 2 -
kernel/softirq.c | 2 -
kernel/softlockup.c | 2 -
kernel/workqueue.c | 2 -
31 files changed, 90 insertions(+), 61 deletions(-)
Index: linux-2.6.21-rc7-mm2/include/linux/sched.h
===================================================================
--- linux-2.6.21-rc7-mm2.orig/include/linux/sched.h 2007-04-27 23:20:23.000000000 +0200
+++ linux-2.6.21-rc7-mm2/include/linux/sched.h 2007-04-28 00:45:20.000000000 +0200
@@ -1006,7 +1006,10 @@ struct task_struct {
/* Deadlock detection and priority inheritance handling */
struct rt_mutex_waiter *pi_blocked_on;
#endif
-
+#ifdef CONFIG_FREEZER
+ /* Used by the process freezer, defined in freezer.h */
+ unsigned long freezer_flags;
+#endif
#ifdef CONFIG_DEBUG_MUTEXES
/* mutex deadlock detection */
struct mutex_waiter *blocked_on;
@@ -1189,8 +1192,6 @@ static inline void put_task_struct(struc
#define PF_MEMALLOC 0x00000800 /* Allocating memory */
#define PF_FLUSHER 0x00001000 /* responsible for disk writeback */
#define PF_USED_MATH 0x00002000 /* if unset the fpu must be initialized before use */
-#define PF_NOFREEZE 0x00008000 /* this thread should not be frozen */
-#define PF_FROZEN 0x00010000 /* frozen for system suspend */
#define PF_FSTRANS 0x00020000 /* inside a filesystem transaction */
#define PF_KSWAPD 0x00040000 /* I am kswapd */
#define PF_SWAPOFF 0x00080000 /* I am in swapoff */
@@ -1202,7 +1203,6 @@ static inline void put_task_struct(struc
#define PF_SPREAD_SLAB 0x02000000 /* Spread some slab caches over cpuset */
#define PF_MEMPOLICY 0x10000000 /* Non-default NUMA mempolicy */
#define PF_MUTEX_TESTER 0x20000000 /* Thread belongs to the rt mutex tester */
-#define PF_FREEZER_SKIP 0x40000000 /* Freezer should not count it as freezeable */
/*
* Only the _current_ task can read/write to tsk->flags, but other
Index: linux-2.6.21-rc7-mm2/include/asm-arm/thread_info.h
===================================================================
--- linux-2.6.21-rc7-mm2.orig/include/asm-arm/thread_info.h 2007-04-27 23:20:23.000000000 +0200
+++ linux-2.6.21-rc7-mm2/include/asm-arm/thread_info.h 2007-04-27 23:23:57.000000000 +0200
@@ -147,7 +147,6 @@ extern void iwmmxt_task_switch(struct th
#define TIF_POLLING_NRFLAG 16
#define TIF_USING_IWMMXT 17
#define TIF_MEMDIE 18
-#define TIF_FREEZE 19
#define _TIF_NOTIFY_RESUME (1 << TIF_NOTIFY_RESUME)
#define _TIF_SIGPENDING (1 << TIF_SIGPENDING)
@@ -155,7 +154,6 @@ extern void iwmmxt_task_switch(struct th
#define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE)
#define _TIF_POLLING_NRFLAG (1 << TIF_POLLING_NRFLAG)
#define _TIF_USING_IWMMXT (1 << TIF_USING_IWMMXT)
-#define _TIF_FREEZE (1 << TIF_FREEZE)
/*
* Change these and you break ASM code in entry-common.S
Index: linux-2.6.21-rc7-mm2/include/asm-blackfin/thread_info.h
===================================================================
--- linux-2.6.21-rc7-mm2.orig/include/asm-blackfin/thread_info.h 2007-04-27 23:20:23.000000000 +0200
+++ linux-2.6.21-rc7-mm2/include/asm-blackfin/thread_info.h 2007-04-27 23:23:57.000000000 +0200
@@ -125,7 +125,6 @@ static inline struct thread_info *curren
TIF_NEED_RESCHED */
#define TIF_MEMDIE 5
#define TIF_RESTORE_SIGMASK 6 /* restore signal mask in do_signal() */
-#define TIF_FREEZE 7 /* is freezing for suspend */
/* as above, but as bit values */
#define _TIF_SYSCALL_TRACE (1<<TIF_SYSCALL_TRACE)
@@ -134,7 +133,6 @@ static inline struct thread_info *curren
#define _TIF_NEED_RESCHED (1<<TIF_NEED_RESCHED)
#define _TIF_POLLING_NRFLAG (1<<TIF_POLLING_NRFLAG)
#define _TIF_RESTORE_SIGMASK (1<<TIF_RESTORE_SIGMASK)
-#define _TIF_FREEZE (1<<TIF_FREEZE)
#define _TIF_WORK_MASK 0x0000FFFE /* work to do on interrupt/exception return */
Index: linux-2.6.21-rc7-mm2/include/asm-frv/thread_info.h
===================================================================
--- linux-2.6.21-rc7-mm2.orig/include/asm-frv/thread_info.h 2007-04-27 23:20:23.000000000 +0200
+++ linux-2.6.21-rc7-mm2/include/asm-frv/thread_info.h 2007-04-27 23:23:57.000000000 +0200
@@ -116,7 +116,6 @@ register struct thread_info *__current_t
#define TIF_RESTORE_SIGMASK 6 /* restore signal mask in do_signal() */
#define TIF_POLLING_NRFLAG 16 /* true if poll_idle() is polling TIF_NEED_RESCHED */
#define TIF_MEMDIE 17 /* OOM killer killed process */
-#define TIF_FREEZE 18 /* freezing for suspend */
#define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE)
#define _TIF_NOTIFY_RESUME (1 << TIF_NOTIFY_RESUME)
@@ -126,7 +125,6 @@ register struct thread_info *__current_t
#define _TIF_IRET (1 << TIF_IRET)
#define _TIF_RESTORE_SIGMASK (1 << TIF_RESTORE_SIGMASK)
#define _TIF_POLLING_NRFLAG (1 << TIF_POLLING_NRFLAG)
-#define _TIF_FREEZE (1 << TIF_FREEZE)
#define _TIF_WORK_MASK 0x0000FFFE /* work to do on interrupt/exception return */
#define _TIF_ALLWORK_MASK 0x0000FFFF /* work to do on any return to u-space */
Index: linux-2.6.21-rc7-mm2/include/asm-i386/thread_info.h
===================================================================
--- linux-2.6.21-rc7-mm2.orig/include/asm-i386/thread_info.h 2007-04-27 23:20:23.000000000 +0200
+++ linux-2.6.21-rc7-mm2/include/asm-i386/thread_info.h 2007-04-27 23:23:57.000000000 +0200
@@ -136,7 +136,6 @@ static inline struct thread_info *curren
#define TIF_MEMDIE 16
#define TIF_DEBUG 17 /* uses debug registers */
#define TIF_IO_BITMAP 18 /* uses I/O bitmap */
-#define TIF_FREEZE 19 /* is freezing for suspend */
#define _TIF_SYSCALL_TRACE (1<<TIF_SYSCALL_TRACE)
#define _TIF_NOTIFY_RESUME (1<<TIF_NOTIFY_RESUME)
@@ -150,7 +149,6 @@ static inline struct thread_info *curren
#define _TIF_RESTORE_SIGMASK (1<<TIF_RESTORE_SIGMASK)
#define _TIF_DEBUG (1<<TIF_DEBUG)
#define _TIF_IO_BITMAP (1<<TIF_IO_BITMAP)
-#define _TIF_FREEZE (1<<TIF_FREEZE)
/* work to do on interrupt/exception return */
#define _TIF_WORK_MASK \
Index: linux-2.6.21-rc7-mm2/include/asm-ia64/thread_info.h
===================================================================
--- linux-2.6.21-rc7-mm2.orig/include/asm-ia64/thread_info.h 2007-04-27 23:20:23.000000000 +0200
+++ linux-2.6.21-rc7-mm2/include/asm-ia64/thread_info.h 2007-04-27 23:23:57.000000000 +0200
@@ -89,7 +89,6 @@ struct thread_info {
#define TIF_MEMDIE 17
#define TIF_MCA_INIT 18 /* this task is processing MCA or INIT */
#define TIF_DB_DISABLED 19 /* debug trap disabled for fsyscall */
-#define TIF_FREEZE 20 /* is freezing for suspend */
#define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE)
#define _TIF_SYSCALL_AUDIT (1 << TIF_SYSCALL_AUDIT)
@@ -101,7 +100,6 @@ struct thread_info {
#define _TIF_POLLING_NRFLAG (1 << TIF_POLLING_NRFLAG)
#define _TIF_MCA_INIT (1 << TIF_MCA_INIT)
#define _TIF_DB_DISABLED (1 << TIF_DB_DISABLED)
-#define _TIF_FREEZE (1 << TIF_FREEZE)
/* "work to do on user-return" bits */
#define TIF_ALLWORK_MASK (_TIF_NOTIFY_RESUME|_TIF_SIGPENDING|_TIF_NEED_RESCHED|_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT)
Index: linux-2.6.21-rc7-mm2/include/asm-mips/thread_info.h
===================================================================
--- linux-2.6.21-rc7-mm2.orig/include/asm-mips/thread_info.h 2007-04-27 23:20:23.000000000 +0200
+++ linux-2.6.21-rc7-mm2/include/asm-mips/thread_info.h 2007-04-27 23:23:57.000000000 +0200
@@ -118,7 +118,6 @@ register struct thread_info *__current_t
#define TIF_USEDFPU 16 /* FPU was used by this task this quantum (SMP) */
#define TIF_POLLING_NRFLAG 17 /* true if poll_idle() is polling TIF_NEED_RESCHED */
#define TIF_MEMDIE 18
-#define TIF_FREEZE 19
#define TIF_SYSCALL_TRACE 31 /* syscall trace active */
#define _TIF_SYSCALL_TRACE (1<<TIF_SYSCALL_TRACE)
@@ -130,7 +129,6 @@ register struct thread_info *__current_t
#define _TIF_RESTORE_SIGMASK (1<<TIF_RESTORE_SIGMASK)
#define _TIF_USEDFPU (1<<TIF_USEDFPU)
#define _TIF_POLLING_NRFLAG (1<<TIF_POLLING_NRFLAG)
-#define _TIF_FREEZE (1<<TIF_FREEZE)
/* work to do on interrupt/exception return */
#define _TIF_WORK_MASK (0x0000ffef & ~_TIF_SECCOMP)
Index: linux-2.6.21-rc7-mm2/include/asm-powerpc/thread_info.h
===================================================================
--- linux-2.6.21-rc7-mm2.orig/include/asm-powerpc/thread_info.h 2007-04-27 23:20:23.000000000 +0200
+++ linux-2.6.21-rc7-mm2/include/asm-powerpc/thread_info.h 2007-04-27 23:23:57.000000000 +0200
@@ -122,7 +122,6 @@ static inline struct thread_info *curren
#define TIF_RESTOREALL 12 /* Restore all regs (implies NOERROR) */
#define TIF_NOERROR 14 /* Force successful syscall return */
#define TIF_RESTORE_SIGMASK 15 /* Restore signal mask in do_signal */
-#define TIF_FREEZE 16 /* Freezing for suspend */
/* as above, but as bit values */
#define _TIF_SYSCALL_TRACE (1<<TIF_SYSCALL_TRACE)
@@ -139,7 +138,6 @@ static inline struct thread_info *curren
#define _TIF_RESTOREALL (1<<TIF_RESTOREALL)
#define _TIF_NOERROR (1<<TIF_NOERROR)
#define _TIF_RESTORE_SIGMASK (1<<TIF_RESTORE_SIGMASK)
-#define _TIF_FREEZE (1<<TIF_FREEZE)
#define _TIF_SYSCALL_T_OR_A (_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT|_TIF_SECCOMP)
#define _TIF_USER_WORK_MASK (_TIF_NOTIFY_RESUME | _TIF_SIGPENDING | \
Index: linux-2.6.21-rc7-mm2/include/asm-sh/thread_info.h
===================================================================
--- linux-2.6.21-rc7-mm2.orig/include/asm-sh/thread_info.h 2007-04-27 23:20:23.000000000 +0200
+++ linux-2.6.21-rc7-mm2/include/asm-sh/thread_info.h 2007-04-27 23:23:57.000000000 +0200
@@ -115,7 +115,6 @@ static inline struct thread_info *curren
#define TIF_USEDFPU 16 /* FPU was used by this task this quantum (SMP) */
#define TIF_POLLING_NRFLAG 17 /* true if poll_idle() is polling TIF_NEED_RESCHED */
#define TIF_MEMDIE 18
-#define TIF_FREEZE 19
#define _TIF_SYSCALL_TRACE (1<<TIF_SYSCALL_TRACE)
#define _TIF_NOTIFY_RESUME (1<<TIF_NOTIFY_RESUME)
@@ -125,7 +124,6 @@ static inline struct thread_info *curren
#define _TIF_SINGLESTEP (1<<TIF_SINGLESTEP)
#define _TIF_USEDFPU (1<<TIF_USEDFPU)
#define _TIF_POLLING_NRFLAG (1<<TIF_POLLING_NRFLAG)
-#define _TIF_FREEZE (1<<TIF_FREEZE)
#define _TIF_WORK_MASK 0x000000FE /* work to do on interrupt/exception return */
#define _TIF_ALLWORK_MASK 0x000000FF /* work to do on any return to u-space */
Index: linux-2.6.21-rc7-mm2/include/asm-x86_64/thread_info.h
===================================================================
--- linux-2.6.21-rc7-mm2.orig/include/asm-x86_64/thread_info.h 2007-04-27 23:20:23.000000000 +0200
+++ linux-2.6.21-rc7-mm2/include/asm-x86_64/thread_info.h 2007-04-27 23:23:57.000000000 +0200
@@ -122,7 +122,6 @@ static inline struct thread_info *stack_
#define TIF_MEMDIE 20
#define TIF_DEBUG 21 /* uses debug registers */
#define TIF_IO_BITMAP 22 /* uses I/O bitmap */
-#define TIF_FREEZE 23 /* is freezing for suspend */
#define _TIF_SYSCALL_TRACE (1<<TIF_SYSCALL_TRACE)
#define _TIF_NOTIFY_RESUME (1<<TIF_NOTIFY_RESUME)
@@ -138,7 +137,6 @@ static inline struct thread_info *stack_
#define _TIF_ABI_PENDING (1<<TIF_ABI_PENDING)
#define _TIF_DEBUG (1<<TIF_DEBUG)
#define _TIF_IO_BITMAP (1<<TIF_IO_BITMAP)
-#define _TIF_FREEZE (1<<TIF_FREEZE)
/* work to do on interrupt/exception return */
#define _TIF_WORK_MASK \
Index: linux-2.6.21-rc7-mm2/include/linux/freezer.h
===================================================================
--- linux-2.6.21-rc7-mm2.orig/include/linux/freezer.h 2007-04-27 23:20:23.000000000 +0200
+++ linux-2.6.21-rc7-mm2/include/linux/freezer.h 2007-04-28 00:45:13.000000000 +0200
@@ -3,12 +3,33 @@
#include <linux/sched.h>
#ifdef CONFIG_FREEZER
+
+/*
+ * Per task flags used by the freezer
+ *
+ * They should not be referred to directly outside of this file.
+ */
+#define TFF_NOFREEZE 0 /* task should not be frozen */
+#define TFF_FREEZE 8 /* task should go to the refrigerator ASAP */
+#define TFF_SKIP 9 /* do not count this task as freezable */
+#define TFF_FROZEN 10 /* task is frozen */
+
/*
* Check if a process has been frozen
*/
static inline int frozen(struct task_struct *p)
{
- return p->flags & PF_FROZEN;
+ return test_bit(TFF_FROZEN, &p->freezer_flags);
+}
+
+static inline void set_frozen_flag(struct task_struct *p)
+{
+ set_bit(TFF_FROZEN, &p->freezer_flags);
+}
+
+static inline void clear_frozen_flag(struct task_struct *p)
+{
+ clear_bit(TFF_FROZEN, &p->freezer_flags);
}
/*
@@ -16,7 +37,7 @@ static inline int frozen(struct task_str
*/
static inline int freezing(struct task_struct *p)
{
- return test_tsk_thread_flag(p, TIF_FREEZE);
+ return test_bit(TFF_FREEZE, &p->freezer_flags);
}
/*
@@ -24,15 +45,31 @@ static inline int freezing(struct task_s
*/
static inline void freeze(struct task_struct *p)
{
- set_tsk_thread_flag(p, TIF_FREEZE);
+ set_bit(TFF_FREEZE, &p->freezer_flags);
+}
+
+/*
+ * Cancel the previous 'freeze' request
+ */
+static inline void clear_freeze_flag(struct task_struct *p)
+{
+ clear_bit(TFF_FREEZE, &p->freezer_flags);
+}
+
+/*
+ * Check if the task wants to be exempted from freezing
+ */
+static inline int freezer_should_exempt(struct task_struct *p)
+{
+ return test_bit(TFF_NOFREEZE, &p->freezer_flags);
}
/*
- * Sometimes we may need to cancel the previous 'freeze' request
+ * Tell the freezer to exempt this task from freezing
*/
-static inline void do_not_freeze(struct task_struct *p)
+static inline void freezer_exempt(struct task_struct *p)
{
- clear_tsk_thread_flag(p, TIF_FREEZE);
+ set_bit(TFF_NOFREEZE, &p->freezer_flags);
}
/*
@@ -48,12 +85,12 @@ static inline int thaw_process(struct ta
{
task_lock(p);
if (frozen(p)) {
- p->flags &= ~PF_FROZEN;
+ clear_frozen_flag(p);
task_unlock(p);
wake_up_process(p);
return 1;
}
- clear_tsk_thread_flag(p, TIF_FREEZE);
+ clear_freeze_flag(p);
task_unlock(p);
return 0;
}
@@ -92,7 +129,7 @@ static inline int try_to_freeze(void)
static inline void freezer_do_not_count(void)
{
if (current->mm)
- current->flags |= PF_FREEZER_SKIP;
+ set_bit(TFF_SKIP, ¤t->freezer_flags);
}
/*
@@ -102,7 +139,7 @@ static inline void freezer_do_not_count(
static inline void freezer_count(void)
{
if (current->mm) {
- current->flags &= ~PF_FREEZER_SKIP;
+ clear_bit(TFF_SKIP, ¤t->freezer_flags);
try_to_freeze();
}
}
@@ -112,13 +149,17 @@ static inline void freezer_count(void)
*/
static inline int freezer_should_skip(struct task_struct *p)
{
- return !!(p->flags & PF_FREEZER_SKIP);
+ return test_bit(TFF_SKIP, ¤t->freezer_flags);
}
#else
static inline int frozen(struct task_struct *p) { return 0; }
+static inline void set_frozen_flag(struct task_struct *p) {}
+static inline void clear_frozen_flag(struct task_struct *p) {}
static inline int freezing(struct task_struct *p) { return 0; }
static inline void freeze(struct task_struct *p) { BUG(); }
+static inline int freezer_should_exempt(struct task_struct *p) { return 0; }
+static inline void freezer_exempt(struct task_struct *p) {}
static inline int thaw_process(struct task_struct *p) { return 1; }
static inline void refrigerator(void) {}
Index: linux-2.6.21-rc7-mm2/kernel/sched.c
===================================================================
--- linux-2.6.21-rc7-mm2.orig/kernel/sched.c 2007-04-27 23:20:23.000000000 +0200
+++ linux-2.6.21-rc7-mm2/kernel/sched.c 2007-04-27 23:23:57.000000000 +0200
@@ -5478,7 +5478,7 @@ migration_call(struct notifier_block *nf
p = kthread_create(migration_thread, hcpu, "migration/%d",cpu);
if (IS_ERR(p))
return NOTIFY_BAD;
- p->flags |= PF_NOFREEZE;
+ freezer_exempt(p);
kthread_bind(p, cpu);
/* Must be high prio: stop_machine expects to yield to it. */
rq = task_rq_lock(p, &flags);
Index: linux-2.6.21-rc7-mm2/arch/i386/kernel/apm.c
===================================================================
--- linux-2.6.21-rc7-mm2.orig/arch/i386/kernel/apm.c 2007-04-27 23:20:23.000000000 +0200
+++ linux-2.6.21-rc7-mm2/arch/i386/kernel/apm.c 2007-04-27 23:23:57.000000000 +0200
@@ -2313,7 +2313,7 @@ static int __init apm_init(void)
remove_proc_entry("apm", NULL);
return err;
}
- kapmd_task->flags |= PF_NOFREEZE;
+ freezer_exempt(kapmd_task);
wake_up_process(kapmd_task);
if (num_online_cpus() > 1 && !smp ) {
Index: linux-2.6.21-rc7-mm2/drivers/block/loop.c
===================================================================
--- linux-2.6.21-rc7-mm2.orig/drivers/block/loop.c 2007-04-27 23:20:23.000000000 +0200
+++ linux-2.6.21-rc7-mm2/drivers/block/loop.c 2007-04-27 23:23:57.000000000 +0200
@@ -582,7 +582,7 @@ static int loop_thread(void *data)
* hence, it mustn't be stopped at all
* because it could be indirectly used during suspension
*/
- current->flags |= PF_NOFREEZE;
+ freezer_exempt(current);
set_user_nice(current, -20);
Index: linux-2.6.21-rc7-mm2/drivers/char/apm-emulation.c
===================================================================
--- linux-2.6.21-rc7-mm2.orig/drivers/char/apm-emulation.c 2007-04-27 23:20:23.000000000 +0200
+++ linux-2.6.21-rc7-mm2/drivers/char/apm-emulation.c 2007-04-27 23:23:57.000000000 +0200
@@ -336,7 +336,7 @@ apm_ioctl(struct inode * inode, struct f
* threads.
*/
flags = current->flags;
- current->flags |= PF_NOFREEZE;
+ freezer_exempt(current);
wait_event(apm_suspend_waitqueue,
as->suspend_state == SUSPEND_DONE);
@@ -372,7 +372,7 @@ apm_ioctl(struct inode * inode, struct f
* threads.
*/
flags = current->flags;
- current->flags |= PF_NOFREEZE;
+ freezer_exempt(current);
wait_event_interruptible(apm_suspend_waitqueue,
as->suspend_state == SUSPEND_DONE);
@@ -601,7 +601,7 @@ static int __init apm_init(void)
kapmd_tsk = NULL;
return ret;
}
- kapmd_tsk->flags |= PF_NOFREEZE;
+ freezer_exempt(kapmd_tsk);
wake_up_process(kapmd_tsk);
#ifdef CONFIG_PROC_FS
Index: linux-2.6.21-rc7-mm2/drivers/ieee1394/ieee1394_core.c
===================================================================
--- linux-2.6.21-rc7-mm2.orig/drivers/ieee1394/ieee1394_core.c 2007-04-27 23:20:23.000000000 +0200
+++ linux-2.6.21-rc7-mm2/drivers/ieee1394/ieee1394_core.c 2007-04-27 23:23:57.000000000 +0200
@@ -1134,7 +1134,7 @@ static int hpsbpkt_thread(void *__hi)
struct list_head tmp;
int may_schedule;
- current->flags |= PF_NOFREEZE;
+ freezer_exempt(current);
while (!kthread_should_stop()) {
Index: linux-2.6.21-rc7-mm2/drivers/md/md.c
===================================================================
--- linux-2.6.21-rc7-mm2.orig/drivers/md/md.c 2007-04-27 23:20:23.000000000 +0200
+++ linux-2.6.21-rc7-mm2/drivers/md/md.c 2007-04-27 23:23:57.000000000 +0200
@@ -4541,7 +4541,7 @@ static int md_thread(void * arg)
* many dirty RAID5 blocks.
*/
- current->flags |= PF_NOFREEZE;
+ freezer_exempt(current);
while (!kthread_should_stop()) {
/* We need to wait INTERRUPTIBLE so that
Index: linux-2.6.21-rc7-mm2/drivers/mmc/card/queue.c
===================================================================
--- linux-2.6.21-rc7-mm2.orig/drivers/mmc/card/queue.c 2007-04-27 23:20:23.000000000 +0200
+++ linux-2.6.21-rc7-mm2/drivers/mmc/card/queue.c 2007-04-27 23:23:57.000000000 +0200
@@ -66,7 +66,8 @@ static int mmc_queue_thread(void *d)
* Set iothread to ensure that we aren't put to sleep by
* the process freezing. We handle suspension ourselves.
*/
- current->flags |= PF_MEMALLOC|PF_NOFREEZE;
+ current->flags |= PF_MEMALLOC;
+ freezer_exempt(current);
down(&mq->thread_sem);
do {
Index: linux-2.6.21-rc7-mm2/drivers/mtd/mtd_blkdevs.c
===================================================================
--- linux-2.6.21-rc7-mm2.orig/drivers/mtd/mtd_blkdevs.c 2007-04-27 23:20:23.000000000 +0200
+++ linux-2.6.21-rc7-mm2/drivers/mtd/mtd_blkdevs.c 2007-04-27 23:23:57.000000000 +0200
@@ -81,7 +81,8 @@ static int mtd_blktrans_thread(void *arg
struct request_queue *rq = tr->blkcore_priv->rq;
/* we might get involved when memory gets low, so use PF_MEMALLOC */
- current->flags |= PF_MEMALLOC | PF_NOFREEZE;
+ current->flags |= PF_MEMALLOC;
+ freezer_exempt(current);
spin_lock_irq(rq->queue_lock);
while (!kthread_should_stop()) {
Index: linux-2.6.21-rc7-mm2/drivers/scsi/libsas/sas_scsi_host.c
===================================================================
--- linux-2.6.21-rc7-mm2.orig/drivers/scsi/libsas/sas_scsi_host.c 2007-04-27 23:20:23.000000000 +0200
+++ linux-2.6.21-rc7-mm2/drivers/scsi/libsas/sas_scsi_host.c 2007-04-27 23:23:57.000000000 +0200
@@ -871,7 +871,7 @@ static int sas_queue_thread(void *_sas_h
struct sas_ha_struct *sas_ha = _sas_ha;
struct scsi_core *core = &sas_ha->core;
- current->flags |= PF_NOFREEZE;
+ freezer_exempt(current);
complete(&queue_th_comp);
Index: linux-2.6.21-rc7-mm2/drivers/scsi/scsi_error.c
===================================================================
--- linux-2.6.21-rc7-mm2.orig/drivers/scsi/scsi_error.c 2007-04-27 23:20:23.000000000 +0200
+++ linux-2.6.21-rc7-mm2/drivers/scsi/scsi_error.c 2007-04-27 23:23:57.000000000 +0200
@@ -1536,7 +1536,7 @@ int scsi_error_handler(void *data)
{
struct Scsi_Host *shost = data;
- current->flags |= PF_NOFREEZE;
+ freezer_exempt(current);
/*
* We use TASK_INTERRUPTIBLE so that the thread is not
Index: linux-2.6.21-rc7-mm2/drivers/usb/storage/usb.c
===================================================================
--- linux-2.6.21-rc7-mm2.orig/drivers/usb/storage/usb.c 2007-04-27 23:20:23.000000000 +0200
+++ linux-2.6.21-rc7-mm2/drivers/usb/storage/usb.c 2007-04-27 23:23:57.000000000 +0200
@@ -301,7 +301,7 @@ static int usb_stor_control_thread(void
struct us_data *us = (struct us_data *)__us;
struct Scsi_Host *host = us_to_host(us);
- current->flags |= PF_NOFREEZE;
+ freezer_exempt(current);
for(;;) {
try_to_freeze();
Index: linux-2.6.21-rc7-mm2/kernel/fork.c
===================================================================
--- linux-2.6.21-rc7-mm2.orig/kernel/fork.c 2007-04-27 23:20:23.000000000 +0200
+++ linux-2.6.21-rc7-mm2/kernel/fork.c 2007-04-27 23:23:57.000000000 +0200
@@ -921,11 +921,14 @@ static inline void copy_flags(unsigned l
{
unsigned long new_flags = p->flags;
- new_flags &= ~(PF_SUPERPRIV | PF_NOFREEZE);
+ new_flags &= ~PF_SUPERPRIV;
new_flags |= PF_FORKNOEXEC;
if (!(clone_flags & CLONE_PTRACE))
p->ptrace = 0;
p->flags = new_flags;
+#ifdef CONFIG_FREEZER
+ p->freezer_flags = 0;
+#endif
}
asmlinkage long sys_set_tid_address(int __user *tidptr)
Index: linux-2.6.21-rc7-mm2/kernel/rcutorture.c
===================================================================
--- linux-2.6.21-rc7-mm2.orig/kernel/rcutorture.c 2007-04-27 23:20:23.000000000 +0200
+++ linux-2.6.21-rc7-mm2/kernel/rcutorture.c 2007-04-27 23:23:57.000000000 +0200
@@ -559,7 +559,7 @@ rcu_torture_fakewriter(void *arg)
VERBOSE_PRINTK_STRING("rcu_torture_fakewriter task started");
set_user_nice(current, 19);
- current->flags |= PF_NOFREEZE;
+ freezer_exempt(current);
do {
schedule_timeout_uninterruptible(1 + rcu_random(&rand)%10);
@@ -590,7 +590,7 @@ rcu_torture_reader(void *arg)
VERBOSE_PRINTK_STRING("rcu_torture_reader task started");
set_user_nice(current, 19);
- current->flags |= PF_NOFREEZE;
+ freezer_exempt(current);
do {
idx = cur_ops->readlock();
Index: linux-2.6.21-rc7-mm2/kernel/softirq.c
===================================================================
--- linux-2.6.21-rc7-mm2.orig/kernel/softirq.c 2007-04-27 23:20:23.000000000 +0200
+++ linux-2.6.21-rc7-mm2/kernel/softirq.c 2007-04-27 23:23:57.000000000 +0200
@@ -490,7 +490,7 @@ void __init softirq_init(void)
static int ksoftirqd(void * __bind_cpu)
{
set_user_nice(current, 15);
- current->flags |= PF_NOFREEZE;
+ freezer_exempt(current);
set_current_state(TASK_INTERRUPTIBLE);
Index: linux-2.6.21-rc7-mm2/kernel/softlockup.c
===================================================================
--- linux-2.6.21-rc7-mm2.orig/kernel/softlockup.c 2007-04-27 23:20:23.000000000 +0200
+++ linux-2.6.21-rc7-mm2/kernel/softlockup.c 2007-04-27 23:23:57.000000000 +0200
@@ -117,7 +117,7 @@ static int watchdog(void * __bind_cpu)
struct sched_param param = { .sched_priority = MAX_RT_PRIO-1 };
sched_setscheduler(current, SCHED_FIFO, ¶m);
- current->flags |= PF_NOFREEZE;
+ freezer_exempt(current);
/* initialize timestamp */
touch_softlockup_watchdog();
Index: linux-2.6.21-rc7-mm2/kernel/workqueue.c
===================================================================
--- linux-2.6.21-rc7-mm2.orig/kernel/workqueue.c 2007-04-27 23:20:23.000000000 +0200
+++ linux-2.6.21-rc7-mm2/kernel/workqueue.c 2007-04-27 23:23:57.000000000 +0200
@@ -291,7 +291,7 @@ static int worker_thread(void *__cwq)
DEFINE_WAIT(wait);
if (!cwq->wq->freezeable)
- current->flags |= PF_NOFREEZE;
+ freezer_exempt(current);
for (;;) {
prepare_to_wait(&cwq->more_work, &wait, TASK_INTERRUPTIBLE);
Index: linux-2.6.21-rc7-mm2/kernel/freezer.c
===================================================================
--- linux-2.6.21-rc7-mm2.orig/kernel/freezer.c 2007-04-27 23:20:23.000000000 +0200
+++ linux-2.6.21-rc7-mm2/kernel/freezer.c 2007-04-27 23:54:02.000000000 +0200
@@ -26,7 +26,7 @@
static inline int freezeable(struct task_struct * p)
{
if ((p == current) ||
- (p->flags & PF_NOFREEZE) ||
+ freezer_should_exempt(p) ||
(p->exit_state != 0))
return 0;
return 1;
@@ -37,11 +37,11 @@ static inline int freezeable(struct task
*/
static inline void frozen_process(void)
{
- if (!unlikely(current->flags & PF_NOFREEZE)) {
- current->flags |= PF_FROZEN;
+ if (!unlikely(freezer_should_exempt(current))) {
+ set_frozen_flag(current);
wmb();
}
- clear_tsk_thread_flag(current, TIF_FREEZE);
+ clear_freeze_flag(current);
}
/* Refrigerator is place where frozen processes are stored :-). */
@@ -100,7 +100,7 @@ static void cancel_freezing(struct task_
if (freezing(p)) {
pr_debug(" clean up: %s\n", p->comm);
- do_not_freeze(p);
+ clear_freeze_flag(p);
spin_lock_irqsave(&p->sighand->siglock, flags);
recalc_sigpending_tsk(p);
spin_unlock_irqrestore(&p->sighand->siglock, flags);
Index: linux-2.6.21-rc7-mm2/Documentation/power/kernel_threads.txt
===================================================================
--- linux-2.6.21-rc7-mm2.orig/Documentation/power/kernel_threads.txt 2007-04-27 23:20:23.000000000 +0200
+++ linux-2.6.21-rc7-mm2/Documentation/power/kernel_threads.txt 2007-04-27 23:23:57.000000000 +0200
@@ -32,7 +32,7 @@ like this:
*/
daemonize("usb-storage");
- current->flags |= PF_NOFREEZE;
+ freezer_exempt(current);
from drivers/usb/storage/usb.c::usb_stor_control_thread()
Index: linux-2.6.21-rc7-mm2/Documentation/power/swsusp.txt
===================================================================
--- linux-2.6.21-rc7-mm2.orig/Documentation/power/swsusp.txt 2007-04-27 23:20:23.000000000 +0200
+++ linux-2.6.21-rc7-mm2/Documentation/power/swsusp.txt 2007-04-27 23:23:57.000000000 +0200
@@ -152,8 +152,8 @@ add:
try_to_freeze();
If the thread is needed for writing the image to storage, you should
-instead set the PF_NOFREEZE process flag when creating the thread (and
-be very careful).
+instead use freezer_exempt() to mark the thread as nonfreezable when creating
+it (and be very careful).
Q: What is the difference between "platform" and "shutdown"?
Index: linux-2.6.21-rc7-mm2/kernel/kthread.c
===================================================================
--- linux-2.6.21-rc7-mm2.orig/kernel/kthread.c 2007-04-27 23:20:23.000000000 +0200
+++ linux-2.6.21-rc7-mm2/kernel/kthread.c 2007-04-27 23:23:57.000000000 +0200
@@ -13,6 +13,7 @@
#include <linux/file.h>
#include <linux/module.h>
#include <linux/mutex.h>
+#include <linux/freezer.h>
#include <asm/semaphore.h>
static DEFINE_SPINLOCK(kthread_create_lock);
@@ -232,7 +233,7 @@ int kthreadd(void *unused)
/* Setup a clean context for our children to inherit. */
kthreadd_setup();
- current->flags |= PF_NOFREEZE;
+ freezer_exempt(current);
for (;;) {
set_current_state(TASK_INTERRUPTIBLE);
^ permalink raw reply [flat|nested] 5+ messages in thread