tools: Fix overflow bug in oping

Sometimes the receiver thread got the SDU before the writer thread has
set the sent time when testing over the local. The sent time is now
written before actually sending to avoid this.

1 files changed, 10 insertions, 9 deletions

diff --git a/src/tools/oping/oping_client.c b/src/tools/oping/oping_client.c
index ee2d9df..99c11a6 100644
--- a/src/tools/oping/oping_client.c
+++ b/src/tools/oping/oping_client.c
@@ -86,7 +86,7 @@ void * reader(void * o)
 
                 ++client.rcvd;
 
-                clock_gettime(CLOCK_REALTIME, &now);
+                clock_gettime(CLOCK_MONOTONIC, &now);
 
                 pthread_mutex_lock(&client.lock);
                 ms = ts_diff_us(&client.times[ntohl(msg->id)], &now)
@@ -105,7 +105,7 @@ void * reader(void * o)
                         client.rtt_max = ms;
 
                 d = (ms - client.rtt_avg);
-                client.rtt_avg += d  / (float) client.rcvd;
+                client.rtt_avg += d / client.rcvd;
                 client.rtt_m2 += d * (ms - client.rtt_avg);
         }
 
@@ -140,18 +140,19 @@ void * writer(void * o)
                 nanosleep(&wait, NULL);
                 msg->type = htonl(ECHO_REQUEST);
                 msg->id = htonl(client.sent);
+
+                clock_gettime(CLOCK_MONOTONIC, &now);
+
+                pthread_mutex_lock(&client.lock);
+                client.times[client.sent++] = now;
+                pthread_mutex_unlock(&client.lock);
+
                 if (flow_write(*fdp, buf, client.size) == -1) {
                         printf("Failed to send SDU.\n");
                         flow_dealloc(*fdp);
                         free(buf);
                         return (void *) -1;
                 }
-
-                clock_gettime(CLOCK_REALTIME, &now);
-
-                pthread_mutex_lock(&client.lock);
-                client.times[client.sent++] = now;
-                pthread_mutex_unlock(&client.lock);
         }
 
         pthread_cleanup_pop(true);
@@ -252,7 +253,7 @@ int client_main(void)
                        client.rtt_max);
                 if (client.rcvd > 1)
                         printf("%.3f ms\n",
-                               sqrt(client.rtt_m2 / (float) (client.rcvd - 1)));
+                               sqrt(client.rtt_m2 / (client.rcvd - 1)));
                 else
                         printf("NaN ms\n");
         }