PM / Core: Introduce struct syscore_ops for core subsystems PM
Some subsystems need to carry out suspend/resume and shutdown
operations with one CPU on-line and interrupts disabled. The only
way to register such operations is to define a sysdev class and
a sysdev specifically for this purpose which is cumbersome and
inefficient. Moreover, the arguments taken by sysdev suspend,
resume and shutdown callbacks are practically never necessary.
For this reason, introduce a simpler interface allowing subsystems
to register operations to be executed very late during system suspend
and shutdown and very early during resume in the form of
strcut syscore_ops objects.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c
index 1832bd2..aeabd26 100644
--- a/kernel/power/hibernate.c
+++ b/kernel/power/hibernate.c
@@ -23,6 +23,7 @@
#include <linux/cpu.h>
#include <linux/freezer.h>
#include <linux/gfp.h>
+#include <linux/syscore_ops.h>
#include <scsi/scsi_scan.h>
#include <asm/suspend.h>
@@ -272,6 +273,8 @@
local_irq_disable();
error = sysdev_suspend(PMSG_FREEZE);
+ if (!error)
+ error = syscore_suspend();
if (error) {
printk(KERN_ERR "PM: Some system devices failed to power down, "
"aborting hibernation\n");
@@ -295,6 +298,7 @@
}
Power_up:
+ syscore_resume();
sysdev_resume();
/* NOTE: dpm_resume_noirq() is just a resume() for devices
* that suspended with irqs off ... no overall powerup.
@@ -403,6 +407,8 @@
local_irq_disable();
error = sysdev_suspend(PMSG_QUIESCE);
+ if (!error)
+ error = syscore_suspend();
if (error)
goto Enable_irqs;
@@ -429,6 +435,7 @@
restore_processor_state();
touch_softlockup_watchdog();
+ syscore_resume();
sysdev_resume();
Enable_irqs:
@@ -516,6 +523,7 @@
local_irq_disable();
sysdev_suspend(PMSG_HIBERNATE);
+ syscore_suspend();
if (pm_wakeup_pending()) {
error = -EAGAIN;
goto Power_up;
@@ -526,6 +534,7 @@
while (1);
Power_up:
+ syscore_resume();
sysdev_resume();
local_irq_enable();
enable_nonboot_cpus();
diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c
index de6f86b..2814c32 100644
--- a/kernel/power/suspend.c
+++ b/kernel/power/suspend.c
@@ -22,6 +22,7 @@
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/suspend.h>
+#include <linux/syscore_ops.h>
#include <trace/events/power.h>
#include "power.h"
@@ -163,11 +164,14 @@
BUG_ON(!irqs_disabled());
error = sysdev_suspend(PMSG_SUSPEND);
+ if (!error)
+ error = syscore_suspend();
if (!error) {
if (!(suspend_test(TEST_CORE) || pm_wakeup_pending())) {
error = suspend_ops->enter(state);
events_check_enabled = false;
}
+ syscore_resume();
sysdev_resume();
}
diff --git a/kernel/sys.c b/kernel/sys.c
index 18da702..1ad48b3 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -37,6 +37,7 @@
#include <linux/ptrace.h>
#include <linux/fs_struct.h>
#include <linux/gfp.h>
+#include <linux/syscore_ops.h>
#include <linux/compat.h>
#include <linux/syscalls.h>
@@ -298,6 +299,7 @@
system_state = SYSTEM_RESTART;
device_shutdown();
sysdev_shutdown();
+ syscore_shutdown();
}
/**
@@ -336,6 +338,7 @@
{
kernel_shutdown_prepare(SYSTEM_HALT);
sysdev_shutdown();
+ syscore_shutdown();
printk(KERN_EMERG "System halted.\n");
kmsg_dump(KMSG_DUMP_HALT);
machine_halt();
@@ -355,6 +358,7 @@
pm_power_off_prepare();
disable_nonboot_cpus();
sysdev_shutdown();
+ syscore_shutdown();
printk(KERN_EMERG "Power down.\n");
kmsg_dump(KMSG_DUMP_POWEROFF);
machine_power_off();