From: Jens Axboe <axboe@kernel.dk>
Date: Tue, 12 Jun 2018 17:37:16 +0000 (-0600)
Subject: rand: ensure that rand_between() can reach max value
X-Git-Tag: fio-3.8~32
X-Git-Url: https://git.kernel.dk/?p=fio.git;a=commitdiff_plain;h=c6fc6d2ab2c2fb905ea859f051ad66a54c607916

rand: ensure that rand_between() can reach max value

We need to add 1, otherwise the maximum generated value will
be end -1. The API is both inclusive.

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

diff --git a/lib/rand.h b/lib/rand.h
index 4f10fb3c..3554f698 100644
--- a/lib/rand.h
+++ b/lib/rand.h
@@ -141,9 +141,9 @@ static inline uint64_t rand_between(struct frand_state *state, uint64_t start,
 				    uint64_t end)
 {
 	if (state->use64)
-		return start + rand64_upto(state, end - start);
+		return start + rand64_upto(state, 1 + end - start);
 	else
-		return start + rand32_upto(state, end - start);
+		return start + rand32_upto(state, 1 + end - start);
 }
 
 extern void init_rand(struct frand_state *, bool);