From e284281285c5f3249bdbf42b55a63e4bb8406933 Mon Sep 17 00:00:00 2001
From: Michal Sojka <sojkam1@fel.cvut.cz>
Date: Tue, 10 Nov 2009 13:31:06 +0100
Subject: [PATCH] fwp-timing: Added histogram and statistics

---
 fwp/tests/timing/fwp-timing.c | 91 ++++++++++++++++++++++++++++++++++-
 1 file changed, 89 insertions(+), 2 deletions(-)

diff --git a/fwp/tests/timing/fwp-timing.c b/fwp/tests/timing/fwp-timing.c
index a594ef3..c0c1b5b 100644
--- a/fwp/tests/timing/fwp-timing.c
+++ b/fwp/tests/timing/fwp-timing.c
@@ -25,10 +25,58 @@
 
 bool opt_verbose = false;
 
+#define HIST_MAX_US 1000000
+#define HIST_RES_US 10
+
+struct histogram {
+	unsigned cnt[(HIST_MAX_US+1)/HIST_RES_US];
+	unsigned max;
+};
+
+/* static void hist_init(struct histogram *h) */
+/* { */
+/* 	memset(h, 0, sizeof(*h)); */
+/* } */
+
+static void hist_add(struct histogram *h, int us)
+{
+	assert(us > 0);
+	if (us > HIST_MAX_US)
+		us = HIST_MAX_US;
+	__sync_fetch_and_add(&h->cnt[us/HIST_RES_US], 1);
+
+	unsigned max;
+	do {
+		max = h->max;
+	} while (us > max && ! __sync_bool_compare_and_swap(&h->max, max, us));
+		
+}
+
+static unsigned hist_get_percentile(struct histogram *h, unsigned p)
+{
+	uint64_t sum = 0, psum;
+	int i;
+	for (i=0; i<(HIST_MAX_US+1)/HIST_RES_US; i++)
+		sum += h->cnt[i];
+
+	psum = sum * p / 100;
+	sum = 0;
+	for (i=0; i<(HIST_MAX_US+1)/HIST_RES_US; i++) {
+		sum += h->cnt[i];
+		if (sum >= psum)
+			break;
+	}
+	return i*HIST_RES_US;
+}
+
 struct stats {
-	
+	uint32_t sent;
+	uint32_t received;
+	uint32_t lost;
 } stats;
 
+struct histogram hist;
+
 void set_rt_prio(int priority)
 {
 	int maxpri, minpri;
@@ -275,6 +323,14 @@ static inline double tsdiff2d(struct timespec *x,
 	return ts2d(&r);
 }
 
+static inline int tsdiff2us(struct timespec *x,
+			      struct timespec *y)
+{
+	struct timespec r;
+	timespec_subtract(&r, x, y);
+	return r.tv_sec*1000000 + r.tv_nsec/1000;
+}
+
 struct msg {
 	int cnt;
 	struct timespec ts;
@@ -302,8 +358,13 @@ void *receiver(void *arg)
 		ret = frsh_receive_sync(epdst, msg, rp->budget, &mlen, NULL);
 		clock_gettime(CLOCK_MONOTONIC, &tsr);
 		tss = msg->ts;
-		if (msg->cnt != last_cnt+1)
+		if (msg->cnt != last_cnt+1) {
 			printf("%3d: packet(s) lost!\n", rp->id);
+			__sync_fetch_and_add(&stats.lost, msg->cnt - last_cnt+1);
+		} else {
+			hist_add(&hist, tsdiff2us(&tsr, &tss));
+			__sync_fetch_and_add(&stats.received, 1);
+		}
 		if (opt_verbose)
 			printf("%3d: %10d: %10.3lf ms\n",
 			       rp->id, msg->cnt, tsdiff2d(&tsr, &tss)*1000);
@@ -359,6 +420,7 @@ void *sender(void *arg)
 			ret = frsh_send_sync(epsrc, msg, p->budget);
 			clock_gettime(CLOCK_MONOTONIC, &next_period);
 		}
+		__sync_fetch_and_add(&stats.sent, 1);
 		next_period.tv_sec  += (p->period_ms/1000);
 		next_period.tv_nsec += (p->period_ms%1000) * 1000000;
 		if (next_period.tv_nsec >= 1000000000) {
@@ -375,6 +437,19 @@ void *sender(void *arg)
 	return NULL;
 }
 
+void print_stat(bool full)
+{
+	printf("Sent: %5d  Received: %5d  Lost: %5d Max: %6.3f ms",
+	       stats.sent, stats.received, stats.lost, hist.max/1000.0);
+	if (full) {
+		printf("  Max: %6.3f ms  90%%: %6.3f ms",
+		       hist_get_percentile(&hist, 100)/1000.0,
+		       hist_get_percentile(&hist, 90)/1000.0);
+	}
+	printf("\r");
+	fflush(stdout);
+}
+
 int main(int argc, char *argv[])
 {
 	int ret;
@@ -411,8 +486,20 @@ int main(int argc, char *argv[])
 		}
 	} while(ret == 0);
 
+	while (!exit_flag) {
+		int v;
+		print_stat(false);
+		sem_getvalue(&finished, &v);
+		if (v == num)
+			break;
+		usleep(100000);
+	}
+
 	while (num--)
 		sem_wait(&finished);
+
+	print_stat(true);
+	printf("\n");
 	
 	return 0;
 }
-- 
2.39.2