Merge pull request #7048 from smlng/enh/ps/schedstats

schedstats: revert to 32Bit, and enhance output of schedstats

core/include/sched.h

@@ -179,7 +179,7 @@ NORETURN void sched_task_exit(void);
  *  Scheduler statistics
  */
 typedef struct {
-    uint64_t laststart;      /**< Time stamp of the last time this thread was
+    uint32_t laststart;      /**< Time stamp of the last time this thread was
                                   scheduled to run */
     unsigned int schedules;  /**< How often the thread was scheduled to run */
     uint64_t runtime_ticks;  /**< The total runtime of this thread in ticks */

core/sched.c

@@ -101,7 +101,7 @@ int __attribute__((used)) sched_run(void)
     }
 
 #ifdef MODULE_SCHEDSTATISTICS
-    uint64_t now = _xtimer_now64();
+    uint32_t now = xtimer_now().ticks32;
 #endif
 
     if (active_thread) {

sys/ps/ps.c

@@ -61,10 +61,10 @@ void ps(void)
 #endif
             "%-9sQ | pri "
 #ifdef DEVELHELP
-           "| stack ( used) | base       | current     "
+           "| stack  ( used) | base addr  | current     "
 #endif
 #ifdef MODULE_SCHEDSTATISTICS
-           "| runtime | switches"
+           "| runtime  | switches"
 #endif
            "\n",
 #ifdef DEVELHELP
@@ -77,13 +77,23 @@ void ps(void)
     void *isr_start = thread_arch_isr_stack_start();
     void *isr_sp = thread_arch_isr_stack_pointer();
     printf("\t  - | isr_stack            | -        - |"
-           "   - | %5i (%5i) | %10p | %10p\n", ISR_STACKSIZE, isr_usage, isr_start, isr_sp);
+           "   - | %6i (%5i) | %10p | %10p\n", ISR_STACKSIZE, isr_usage, isr_start, isr_sp);
     overall_stacksz += ISR_STACKSIZE;
     if (isr_usage > 0) {
         overall_used += isr_usage;
     }
 #endif
 
+#ifdef MODULE_SCHEDSTATISTICS
+    uint64_t rt_sum = 0;
+    for (kernel_pid_t i = KERNEL_PID_FIRST; i <= KERNEL_PID_LAST; i++) {
+        thread_t *p = (thread_t *)sched_threads[i];
+        if (p != NULL) {
+            rt_sum += sched_pidlist[i].runtime_ticks;
+        }
+    }
+#endif /* MODULE_SCHEDSTATISTICS */
+
     for (kernel_pid_t i = KERNEL_PID_FIRST; i <= KERNEL_PID_LAST; i++) {
         thread_t *p = (thread_t *)sched_threads[i];
 
@@ -98,9 +108,11 @@ void ps(void)
             overall_used += stacksz;
 #endif
 #ifdef MODULE_SCHEDSTATISTICS
-            double runtime_ticks = sched_pidlist[i].runtime_ticks /
-                                   (double) _xtimer_now64() * 100;
-            int switches = sched_pidlist[i].schedules;
+            /* multiply with 100 for percentage and to avoid floats/doubles */
+            uint64_t runtime_ticks = sched_pidlist[i].runtime_ticks * 100;
+            unsigned runtime_major = runtime_ticks / rt_sum;
+            unsigned runtime_minor = ((runtime_ticks % rt_sum) * 1000) / rt_sum;
+            unsigned switches = sched_pidlist[i].schedules;
 #endif
             printf("\t%3" PRIkernel_pid
 #ifdef DEVELHELP
@@ -108,10 +120,10 @@ void ps(void)
 #endif
                    " | %-8s %.1s | %3i"
 #ifdef DEVELHELP
-                   " | %5i (%5i) | %10p | %10p "
+                   " | %6i (%5i) | %10p | %10p "
 #endif
 #ifdef MODULE_SCHEDSTATISTICS
-                   " | %6.3f%% |  %8d"
+                   " | %2d.%03d%% |  %8u"
 #endif
                    "\n",
                    p->pid,
@@ -123,14 +135,14 @@ void ps(void)
                    , p->stack_size, stacksz, (void *)p->stack_start, (void *)p->sp
 #endif
 #ifdef MODULE_SCHEDSTATISTICS
-                   , runtime_ticks, switches
+                   , runtime_major, runtime_minor, switches
 #endif
                   );
         }
     }
 
 #ifdef DEVELHELP
-    printf("\t%5s %-21s|%13s%6s %5i (%5i)\n", "|", "SUM", "|", "|",
+    printf("\t%5s %-21s|%13s%6s %6i (%5i)\n", "|", "SUM", "|", "|",
            overall_stacksz, overall_used);
 #   ifdef MODULE_TLSF
     puts("\nHeap usage:");

tests/ps_schedstatistics/main.c

 /*
  * Copyright (C) 2017 OTA keys S.A.
+ *               2017 HAW Hamburg
  *
  * This file is subject to the terms and conditions of the GNU Lesser
  * General Public License v2.1. See the file LICENSE in the top level
@@ -14,6 +15,7 @@
  * @brief ps schedstatistics test app
  *
  * @author Vincent Dupont <vincent@otakeys.com>
+ * @author Sebastian Meiling <s@mlng.net>
  *
  * @}
  */
@@ -25,23 +27,26 @@
 #include <thread.h>
 #include <xtimer.h>
 
-#define NB_THREADS 5
+#define NB_THREADS  (5U)
 
 static char stacks[NB_THREADS][THREAD_STACKSIZE_DEFAULT];
 static kernel_pid_t pids[NB_THREADS];
 
 static void *_thread_fn(void *arg)
 {
-    int next = (int)arg < NB_THREADS - 1 ? (int)arg + 1 : 0;
-    msg_t msg;
+    int next = ((int)arg + 1) % NB_THREADS;
 
     printf("Creating thread #%d, next=%d\n", (int)arg, next);
 
     while (1) {
-        msg_receive(&msg);
-        xtimer_usleep(XTIMER_BACKOFF - 1);
-        xtimer_usleep(2 * XTIMER_BACKOFF);
-        msg_send(&msg, pids[next]);
+        msg_t m1, m2;
+        msg_receive(&m1);
+        /* generate differents loads per thead */
+        for (int i = 0; i < (10 * (next + 1)); ++i) {
+            _xtimer_now64();
+        }
+        xtimer_usleep(XTIMER_BACKOFF * 3);
+        msg_send(&m2, pids[next]);
     }
 
     return NULL;
@@ -49,13 +54,14 @@ static void *_thread_fn(void *arg)
 
 int main(void)
 {
-    for (int i = 0; i < NB_THREADS; i++) {
+    for (unsigned i = 0; i < NB_THREADS; ++i) {
         pids[i] = thread_create(stacks[i], sizeof(stacks[i]),
-                                THREAD_PRIORITY_MAIN + 1,
+                                THREAD_PRIORITY_MAIN - 1,
                                 THREAD_CREATE_STACKTEST,
                                 _thread_fn, (void *)i, "thread");
     }
-
+    /* sleep for a second, so that `ps` shows some % on idle at the beginning */
+    xtimer_sleep(1);
 
     msg_t msg;
     msg_send(&msg, pids[0]);