Program canping extended to provide option for selection of real-time priorities.

diff --git a/src/canping.c b/src/canping.c
index 10c605e770a446e75152f3d8420c2295f6d5d745..eb829b3d8f816c999a319c0979d95c7c90c61ff5 100644 (file)
--- a/src/canping.c
+++ b/src/canping.c
@@ -20,6 +20,16 @@
 
 //#define DEBUG 1
 //#define DEBUG 2
+#define WITH_RTPRIO
+
+#ifdef WITH_RTPRIO
+#include <sched.h>
+
+int sched_policy = SCHED_OTHER;
+int sched_rtprio;
+
+#endif
+
 
 #ifndef DEBUG
 #define dbg(level, fmt, arg...) do {} while (0)
@@ -445,6 +455,28 @@ void start_slaves(int slaves, int first_id)
        }
 }
 
+#ifdef WITH_RTPRIO
+int set_sched_policy_and_prio(int policy, int rtprio)
+{
+       struct sched_param scheduling_parameters;
+       int maxprio=sched_get_priority_max(policy);
+       int minprio=sched_get_priority_min(policy);
+
+       if((rtprio < minprio) || (rtprio > maxprio)) {
+               fprintf(stderr, "The priority for requested policy is out of <%d, %d> range\n",
+                               minprio, maxprio);
+               return -1;
+       }
+
+       scheduling_parameters.sched_priority = rtprio;
+
+       if (0 != pthread_setschedparam(pthread_self(), policy, &scheduling_parameters)) {
+               perror("pthread_setschedparam error");
+       }
+       return 0;
+}
+#endif
+
 void print_help(void)
 {
        printf("Usage: canping -m <master threads> [other options]\n"
@@ -461,6 +493,10 @@ void print_help(void)
               "  -w ms         wait ms miliseconds between sending pings\n"
               "  -y            synchronize threads before start (doesn't test race conditions\n"
               "                between open and read/write)\n"
+#ifdef WITH_RTPRIO
+              "  -r            run at realtime priority\n"
+              "  -R P:prio     run at realtime priority prio, policy RR or FF\n"
+#endif
               "\n"
               "Example: canping -m 10 -vv\n"
                );
@@ -471,7 +507,7 @@ int parse_options(int argc, char *argv[])
        int c;
        
        opterr = 0;
-       while ((c = getopt (argc, argv, "c:d:hi:l:m:os:t:vw:y")) != -1)
+       while ((c = getopt (argc, argv, "c:d:hi:l:m:os:t:vw:yrR:")) != -1)
                switch (c)
                {
                case 'c':
@@ -513,6 +549,28 @@ int parse_options(int argc, char *argv[])
                case 'y':
                        option_synch_start = 1;
                        break;
+#ifdef WITH_RTPRIO
+               case 'r':
+                       sched_policy = SCHED_FIFO;
+                       sched_rtprio = (sched_get_priority_min(SCHED_FIFO) +
+                                       sched_get_priority_max(SCHED_FIFO)) / 2;
+                       break;
+               case 'R':
+                       if(!isalpha(*optarg)) {
+                               sched_policy = SCHED_FIFO;
+                       } else if(!strncmp(optarg,"FF:",3)) {
+                               sched_policy = SCHED_FIFO;
+                               optarg += 3;
+                       } else if(!strncmp(optarg,"RR:",3)) {
+                               sched_policy = SCHED_RR;
+                               optarg += 3;
+                       } else {
+                               fprintf (stderr, "Unknown policy %s\n", optarg);
+                               exit(EXIT_BAD_PARAM);
+                       }
+                       sched_rtprio = atoi(optarg);
+                       break;
+#endif
                case '?':
                        if (isprint (optopt))
                                fprintf (stderr, "Unknown option `-%c'.\n", optopt);
@@ -606,6 +664,13 @@ int main(int argc, char *argv[])
 {
        parse_options(argc, argv);
 
+#ifdef WITH_RTPRIO
+       if(sched_policy != SCHED_OTHER)
+               if(set_sched_policy_and_prio(sched_policy, sched_rtprio) <0)
+                       exit(EXIT_BAD_PARAM);
+#endif
+
+
        thread_list_init_head(&master_threads);
        thread_list_init_head(&slave_threads);