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/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();