From: Jens Axboe <axboe@kernel.dk>
Date: Fri, 3 Aug 2018 20:35:57 +0000 (-0600)
Subject: iolog: fix potential div-by-zero
X-Git-Tag: fio-3.9~48
X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;ds=sidebyside;h=fe3b769cf49456c7b7dc593ae3a1ebc6af27a1ab;p=fio.git

iolog: fix potential div-by-zero

Signed-off-by: Jens Axboe <axboe@kernel.dk>
---

diff --git a/iolog.c b/iolog.c
index b0122bed..07692fb2 100644
--- a/iolog.c
+++ b/iolog.c
@@ -370,15 +370,21 @@ static bool read_iolog2(struct thread_data *td)
 			struct timespec now;
 			uint64_t elapsed;
 			uint64_t for_1s;
+
 			fio_gettime(&now, NULL);
 			elapsed = ntime_since(&td->io_log_highmark_time, &now);
-			for_1s = (td->io_log_highmark - td->io_log_current) * 1000000000 / elapsed;
-			items_to_fetch = for_1s - td->io_log_current;
+			if (elapsed) {
+				for_1s = (td->io_log_highmark - td->io_log_current) * 1000000000 / elapsed;
+				items_to_fetch = for_1s - td->io_log_current;
+			} else
+				items_to_fetch = 0;
 			if (items_to_fetch < 0)
 				items_to_fetch = 0;
+
 			td->io_log_highmark = td->io_log_current + items_to_fetch;
 			td->io_log_checkmark = (td->io_log_highmark + 1) / 2;
 			fio_gettime(&td->io_log_highmark_time, NULL);
+
 			if (items_to_fetch == 0)
 				return true;
 		}