renegade-project/linux-next
2
0
Fork 0
mirror of https://github.com/edk2-porting/linux-next.git synced 2024-12-22 20:23:57 +08:00
Code

um: Allow PM with suspend-to-idle

Browse Source 
In order to be able to experiment with suspend in UML, add the
minimal work to be able to suspend (s2idle) an instance of UML,
and be able to wake it back up from that state with the USR1
signal sent to the main UML process.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Acked-By: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
This commit is contained in:
Johannes Berg 2020-12-02 20:58:06 +01:00 committed by Richard Weinberger
parent 2701c1bd91
commit 92dcd3d318
5 changed files with 46 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
arch/um/Kconfig
View File

@ -192,3 +192,8 @@ config UML_TIME_TRAVEL_SUPPORT
endmenu
source "arch/um/drivers/Kconfig"
config ARCH_SUSPEND_POSSIBLE
def_bool y
source "kernel/power/Kconfig"

2
arch/um/include/shared/kern_util.h
View File

@ -39,6 +39,8 @@ extern int is_syscall(unsigned long addr);
extern void timer_handler(int sig, struct siginfo *unused_si, struct uml_pt_regs *regs);
extern void uml_pm_wake(void);
extern int start_uml(void);
extern void paging_init(void);

1
arch/um/include/shared/os.h
View File

@ -241,6 +241,7 @@ extern int set_signals(int enable);
extern int set_signals_trace(int enable);
extern int os_is_signal_stack(void);
extern void deliver_alarm(void);
extern void register_pm_wake_signal(void);
/* util.c */
extern void stack_protections(unsigned long address);

25
arch/um/kernel/um_arch.c
View File

@ -13,6 +13,7 @@
#include <linux/sched.h>
#include <linux/sched/task.h>
#include <linux/kmsg_dump.h>
#include <linux/suspend.h>
#include <asm/processor.h>
#include <asm/sections.h>
@ -377,3 +378,27 @@ void *text_poke(void *addr, const void *opcode, size_t len)
void text_poke_sync(void)
{
}
#ifdef CONFIG_PM_SLEEP
void uml_pm_wake(void)
{
pm_system_wakeup();
}
static int init_pm_wake_signal(void)
{
/*
* In external time-travel mode we can't use signals to wake up
* since that would mess with the scheduling. We'll have to do
* some additional work to support wakeup on virtio devices or
* similar, perhaps implementing a fake RTC controller that can
* trigger wakeup (and request the appropriate scheduling from
* the external scheduler when going to suspend.)
*/
if (time_travel_mode != TT_MODE_EXTERNAL)
register_pm_wake_signal();
return 0;
}
late_initcall(init_pm_wake_signal);
#endif

14
arch/um/os-Linux/signal.c
View File

@ -136,6 +136,16 @@ void set_sigstack(void *sig_stack, int size)
panic("enabling signal stack failed, errno = %d\n", errno);
}
static void sigusr1_handler(int sig, struct siginfo *unused_si, mcontext_t *mc)
{
uml_pm_wake();
}
void register_pm_wake_signal(void)
{
set_handler(SIGUSR1);
}
static void (*handlers[_NSIG])(int sig, struct siginfo *si, mcontext_t *mc) = {
[SIGSEGV] = sig_handler,
[SIGBUS] = sig_handler,
@ -145,7 +155,9 @@ static void (*handlers[_NSIG])(int sig, struct siginfo *si, mcontext_t *mc) = {
[SIGIO] = sig_handler,
[SIGWINCH] = sig_handler,
[SIGALRM] = timer_alarm_handler
[SIGALRM] = timer_alarm_handler,
[SIGUSR1] = sigusr1_handler,
};
static void hard_handler(int sig, siginfo_t *si, void *p)