test/sysperf/upcall1.c

   1 /*
   2  * UPCALL1.C
   3  *
   4  *      Test upcall performance.  WARNING!  This test does not reflect
   5  *      reality... the test is effectively making two system calls for
   6  *      each upcall when under normal conditions no system calls should be
   7  *      necessary when handling an upcall.
   8  *
   9  * $DragonFly: src/test/sysperf/upcall1.c,v 1.3 2004/01/12 17:48:37 drhodus Exp $
  10  */
  11
  12 #include <sys/types.h>
  13 #include <sys/upcall.h>
  14 #include <sys/time.h>
  15 #include <stdio.h>
  16 #include "blib.h"
  17
  18 #define MAXCOUNT        10000000
  19
  20 struct upcall   upc;                    /* simple single-cpu upcall test */
  21
  22 extern void callused_wrapper(void *);   /* assembly */
  23 static void myfunc(void *data);
  24
  25 int count = MAXCOUNT;
  26 int id;
  27
  28 int
  29 main(int ac, char **av)
  30 {
  31         id = upc_register(&upc, callused_wrapper, myfunc, "blah");
  32         printf("Warning: extra system calls in test means performance\n");
  33         printf("does not reflect reality.  Divide times by 3 for raw\n");
  34         printf("per-upcall overhead (approximately)\n");
  35         printf("register upcall %d\n", id);
  36         printf("try to dispatch the upcall\n");
  37         upc_control(UPC_CONTROL_DISPATCH, id, NULL);
  38         stop_timing(MAXCOUNT, "Full-up upcall test");
  39         printf("final: %d %d (should be 0 0)\n", upc.upc_critoff, upc.upc_pending);
  40         return 0;
  41 }
  42
  43 static void
  44 myfunc(void *data)
  45 {
  46     /*
  47      * Dispatch a reentrant UPC.  It should not stack because we are in a
  48      * critical section, but the context code will catch it when it calls
  49      * UPC_CONTROL_NEXT.
  50      */
  51     if (--count > 0) {
  52         upc_control(UPC_CONTROL_DISPATCH, id, NULL);
  53     }
  54     if (count > MAXCOUNT - 3) {
  55         printf("UPCALL! (%s) upc: %d crit=%d pend=%d (should be 32 1) @sp %p\n",
  56                 data, upc.upc_magic, upc.upc_critoff, upc.upc_pending, &data);
  57         if (count == MAXCOUNT - 2) {
  58             printf("(sp should be same as before)\n");
  59             printf("doing a total of %d upcalls\n", MAXCOUNT);
  60             usleep(20000);
  61             start_timing();
  62         }
  63     }
  64 }
  65