[PATCH] blkparse: don't print an error on failure to find request

This can happen if we lose or have out-of-order events when
passing the data through a pipe.

diff --git a/blkparse.c b/blkparse.c
index 74f44dca223ec436ee3a6844906ed166ba370b42..f4aecebed3665046c5a22334b3fefaf43e7b3ffa 100644 (file)
--- a/blkparse.c
+++ b/blkparse.c
@@ -360,15 +360,15 @@ static void log_track_merge(struct blk_io_trace *t)
        if ((t->action & BLK_TC_ACT(BLK_TC_FS)) == 0)
                return;
 
+       /*
+        * this can happen if we lose events, so don't print an error
+        */
        iot = __find_track(t->device, t->sector - (t->bytes >> 10));
-       if (!iot) {
-               fprintf(stderr, "Trying to merge on non-existing request\n");
-               return;
+       if (iot) {
+               rb_erase(&iot->rb_node, &rb_track_root);
+               iot->sector -= t->bytes >> 10;
+               track_rb_insert(iot);
        }
-
-       rb_erase(&iot->rb_node, &rb_track_root);
-       iot->sector -= t->bytes >> 10;
-       track_rb_insert(iot);
 }
 
 static void log_track_getrq(struct blk_io_trace *t)
@@ -422,11 +422,12 @@ static unsigned long long log_track_issue(struct blk_io_trace *t)
        if ((t->action & BLK_TC_ACT(BLK_TC_FS)) == 0)
                return -1;
 
+       /*
+        * this can happen if we lose events, so don't print an error
+        */
        iot = __find_track(t->device, t->sector);
-       if (!iot) {
-               fprintf(stderr, "Trying to issue on non-existing request\n");
+       if (!iot)
                return -1;
-       }
 
        iot->dispatch_time = t->time;
        elapsed = iot->dispatch_time - iot->queue_time;
@@ -456,10 +457,8 @@ static unsigned long long log_track_complete(struct blk_io_trace *t)
                return -1;
 
        iot = __find_track(t->device, t->sector);
-       if (!iot) {
-               fprintf(stderr, "Trying to dispatch on non-existing request\n");
+       if (!iot)
                return -1;
-       }
 
        iot->completion_time = t->time;
        elapsed = iot->completion_time - iot->dispatch_time;