[PATCH v2 4/8] kvm tools: Pause/resume guest using SIGUSR2

[Sasha Levin <levinsasha928@gmail.com>]

Make SIGUSR2 pause/resume a guest, this allows to easily test
pausing a guest.
Can be tested using cmdline 'kill -USR2 $(pidof kvm)'.

Signed-off-by: Sasha Levin <levinsasha928@gmail.com>
---
 tools/kvm/kvm-run.c |   15 +++++++++++++++
 1 files changed, 15 insertions(+), 0 deletions(-)

diff --git a/tools/kvm/kvm-run.c b/tools/kvm/kvm-run.c
index 761ac0d..49cc0aa 100644
--- a/tools/kvm/kvm-run.c
+++ b/tools/kvm/kvm-run.c
@@ -165,6 +165,20 @@ static void handle_sigusr1(int sig)
 	mb();
 }
 
+/* Pause/resume the guest using SIGUSR2 */
+static int is_paused;
+
+static void handle_sigusr2(int sig)
+{
+	if (is_paused)
+		kvm__continue();
+	else
+		kvm__pause();
+
+	is_paused = !is_paused;
+	pr_info("Guest %s\n", is_paused?"paused":"resumed");
+}
+
 static void handle_sigquit(int sig)
 {
 	int i;
@@ -422,6 +436,7 @@ int kvm_cmd_run(int argc, const char **argv, const char *prefix)
 	signal(SIGALRM, handle_sigalrm);
 	signal(SIGQUIT, handle_sigquit);
 	signal(SIGUSR1, handle_sigusr1);
+	signal(SIGUSR2, handle_sigusr2);
 
 	nr_online_cpus = sysconf(_SC_NPROCESSORS_ONLN);
 
-- 
1.7.5.rc3