workspace/ksysguard/gui/setscheduler.c

   1 #include <stdio.h>
   2 #include <stdlib.h>
   3 #include <sched.h>
   4
   5 int main(int argc, char **argv)
   6 {
   7         if(argc != 4) {
   8                 fprintf(stderr, "Usage: %s PID SCHEDULER PRIORITY\n", argv[0]);
   9                 fprintf(stderr, "Sets the CPU Scheduler and priority for the given PID.\n  See man sched_setscheduler for more information\n\n");
  10                 fprintf(stderr, "SCHEDULER is one of:\n");
  11                 fprintf(stderr, "               0       Other\n");
  12                 fprintf(stderr, "               1       FIFO\n");
  13                 fprintf(stderr, "               2       RoundRobin\n");
  14 #ifdef SCHED_BATCH
  15                 fprintf(stderr, "               3       Batch\n");
  16 #endif
  17                 exit(EXIT_FAILURE);
  18         }
  19         int pid = atoi(argv[1]);
  20         int priorityClass = atoi(argv[2]);
  21         int priority = atoi(argv[3]);
  22         printf("Setting scheduler for %d to %d %d\n", pid, priorityClass, priority);
  23
  24         struct sched_param params;
  25         params.sched_priority = priority;
  26         int result;
  27         switch(priorityClass) {
  28                 case 0:
  29                         result = sched_setscheduler( pid, SCHED_OTHER, &params);
  30                         break;
  31                 case 1:
  32                         result = sched_setscheduler( pid, SCHED_FIFO, &params);
  33                         break;
  34                 case 2:
  35                         result = sched_setscheduler( pid, SCHED_RR, &params);;
  36                         break;
  37 #ifdef SCHED_BATCH
  38                 case 3:
  39                         result = sched_setscheduler( pid, SCHED_BATCH, &params);
  40                         break;
  41 #endif
  42                 default:
  43                         fprintf(stderr, "Invalid Priority class\n");
  44                         exit(EXIT_FAILURE);
  45         }
  46         if(result != 0) {
  47                 perror("Failure setting scheduler");
  48         }
  49
  50         return result;
  51 }