kernel/debug.c

   1 /* This file implements kernel debugging functionality that is not included
   2  * in the standard kernel. Available functionality includes timing of lock
   3  * functions and sanity checking of the scheduling queues.
   4  */
   5
   6 #include "kernel.h"
   7 #include "proc.h"
   8 #include "debug.h"
   9
  10 #include <minix/sysutil.h>
  11 #include <limits.h>
  12 #include <string.h>
  13
  14 #if DEBUG_SCHED_CHECK           /* only include code if enabled */
  15
  16 #define MAX_LOOP (NR_PROCS + NR_TASKS)
  17
  18 PUBLIC void
  19 check_runqueues_f(char *file, int line)
  20 {
  21   int q, l = 0;
  22   register struct proc *xp;
  23 #define MYPANIC(msg) {          \
  24         static char buf[100];   \
  25         strcpy(buf, file);      \
  26         strcat(buf, ": ");      \
  27         util_nstrcat(buf, line);\
  28         strcat(buf, ": ");      \
  29         strcat(buf, msg);       \
  30         minix_panic(buf, NO_NUM);       \
  31         }
  32
  33   for (xp = BEG_PROC_ADDR; xp < END_PROC_ADDR; ++xp) {
  34         xp->p_found = 0;
  35         if (l++ > MAX_LOOP) {  MYPANIC("check error"); }
  36   }
  37
  38   for (q=l=0; q < NR_SCHED_QUEUES; q++) {
  39     if (rdy_head[q] && !rdy_tail[q]) {
  40         kprintf("head but no tail in %d\n", q);
  41                  MYPANIC("scheduling error");
  42     }
  43     if (!rdy_head[q] && rdy_tail[q]) {
  44         kprintf("tail but no head in %d\n", q);
  45                  MYPANIC("scheduling error");
  46     }
  47     if (rdy_tail[q] && rdy_tail[q]->p_nextready != NIL_PROC) {
  48         kprintf("tail and tail->next not null in %d\n", q);
  49                  MYPANIC("scheduling error");
  50     }
  51     for(xp = rdy_head[q]; xp != NIL_PROC; xp = xp->p_nextready) {
  52         if (!xp->p_ready) {
  53                 kprintf("scheduling error: unready on runq %d proc %d\n",
  54                         q, xp->p_nr);
  55                 MYPANIC("found unready process on run queue");
  56         }
  57         if (xp->p_priority != q) {
  58                 kprintf("scheduling error: wrong priority q %d proc %d\n",
  59                         q, xp->p_nr);
  60                 MYPANIC("wrong priority");
  61         }
  62         if (xp->p_found) {
  63                 kprintf("scheduling error: double sched q %d proc %d\n",
  64                         q, xp->p_nr);
  65                 MYPANIC("proc more than once on scheduling queue");
  66         }
  67         xp->p_found = 1;
  68         if (xp->p_nextready == NIL_PROC && rdy_tail[q] != xp) {
  69                 kprintf("sched err: last element not tail q %d proc %d\n",
  70                         q, xp->p_nr);
  71                 MYPANIC("scheduling error");
  72         }
  73         if (l++ > MAX_LOOP) MYPANIC("loop in schedule queue?");
  74     }
  75   }
  76
  77   l = 0;
  78   for (xp = BEG_PROC_ADDR; xp < END_PROC_ADDR; ++xp) {
  79         if (! isemptyp(xp) && xp->p_ready && ! xp->p_found) {
  80                 kprintf("sched error: ready proc %d not on queue\n", xp->p_nr);
  81                 MYPANIC("ready proc not on scheduling queue");
  82                 if (l++ > MAX_LOOP) { MYPANIC("loop in debug.c?"); }
  83         }
  84   }
  85 }
  86
  87 #endif /* DEBUG_SCHED_CHECK */