Set SCHED_RR

uvrrpd.c

@@ -25,6 +25,11 @@
 #include <signal.h>
 #include <sys/file.h>
 #include <sys/mman.h>
+#ifdef _POSIX_PRIORITY_SCHEDULING
+  #include <sched.h>
+#else
+  #warning "no sched rt"
+#endif
 
 #include "uvrrpd.h"
 #include "vrrp.h"
@@ -128,6 +133,8 @@ int main(int argc, char *argv[])
 
 	/* lock procress's virtual address space into RAM */
 	mlockall(MCL_CURRENT | MCL_FUTURE);
+	/* set SCHED_RR */
+	uvrrpd_sched_set();
 
 	/* process */
 	set_bit(KEEP_GOING, &reg);
@@ -412,3 +419,40 @@ static void ctrlfile(int vrid, int *fd)
 		exit(EXIT_FAILURE);
 	}
 }
+
+/**
+ * uvrrpd_sched_set() - set SCHED_RR scheduler
+ */
+int uvrrpd_sched_set()
+{
+#ifdef _POSIX_PRIORITY_SCHEDULING
+	struct sched_param param;
+
+	param.sched_priority = sched_get_priority_max(SCHED_RR);
+	if (sched_setscheduler(0, SCHED_RR, &param) != 0) {
+		log_error("sched_setscheduler() - %m");
+		return -1;
+	}
+#else
+	nice(-20);
+#endif
+
+	return 0;
+}
+
+/**
+ * uvrrpd_sched_unset() - unset SCHED_RR scheduler
+ */
+int uvrrpd_sched_unset()
+{
+#ifdef _POSIX_PRIORITY_SCHEDULING
+	struct sched_param param;
+
+	param.sched_priority = sched_get_priority_max(SCHED_OTHER);
+	if (sched_setscheduler(0, SCHED_OTHER, &param) != 0) {
+		log_error("sched_setscheduler() - %m");
+		return -1;
+	}
+#endif
+	return 0;
+}

uvrrpd.h

@@ -42,4 +42,7 @@ enum uvrrpd_control {
 	UVRRPD_RELOAD = BIT_MASK(3),
 };
 
+int uvrrpd_sched_set(void);
+int uvrrpd_sched_unset(void);
+
 #endif /* _UVRRPD_ */

vrrp_exec.c

@@ -31,6 +31,7 @@
 
 #include "vrrp.h"
 #include "vrrp_exec.h"
+#include "uvrrpd.h"
 #include "common.h"
 #include "log.h"
 
@@ -137,6 +138,7 @@ int vrrp_exec(struct vrrp *vrrp, const struct vrrp_net *vnet, vrrp_state state)
 	sigaction(SIGQUIT, &sa_ignore, &sa_origquit);
 
 	/* fork */
+	uvrrpd_sched_unset(); /* remove SCHED_RR */
 	pid_t child = fork();
 	int status, savedErrno;
 
@@ -167,7 +169,8 @@ int vrrp_exec(struct vrrp *vrrp, const struct vrrp_net *vnet, vrrp_state state)
 
 	/* parent */
 	if (child > 0) {
-
+		
+		uvrrpd_sched_set(); /* restore SCHED_RR */
 		while (waitpid(child, &status, 0) == -1) {
 			if (errno != EINTR) {	/* Error other than EINTR */
 				log_error("vrid %d :: waitpid - %m", vrrp->vrid);