From 92dcd3d31843fbe1a95d880dc912e1f6beac6632 Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Wed, 2 Dec 2020 20:58:06 +0100 Subject: um: Allow PM with suspend-to-idle 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 Acked-By: Anton Ivanov Signed-off-by: Richard Weinberger --- arch/um/os-Linux/signal.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) (limited to 'arch/um/os-Linux/signal.c') diff --git a/arch/um/os-Linux/signal.c b/arch/um/os-Linux/signal.c index b58bc68cbe64..0a2ea84033b4 100644 --- a/arch/um/os-Linux/signal.c +++ b/arch/um/os-Linux/signal.c @@ -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) -- cgit v1.2.3