X-Git-Url: https://git.kernel.dk/?a=blobdiff_plain;f=lib%2Frand.h;h=1676cf98ed567653cded97eaf00a1beabe808b58;hb=d5bb0a8902b787718e7027be85573773781f0898;hp=6be53072a64751c4ae864a439e33a374205e3c4b;hpb=56c77c10f79d7be492aa0fb137786978c3596682;p=fio.git

diff --git a/lib/rand.h b/lib/rand.h
index 6be53072..1676cf98 100644
--- a/lib/rand.h
+++ b/lib/rand.h
@@ -114,35 +114,38 @@ static inline double __rand_0_1(struct frand_state *state)
 	}
 }
 
-/*
- * Generate a random value between 'start' and 'end', both inclusive
- */
-static inline int rand32_between(struct frand_state *state, int start, int end)
+static inline uint32_t rand32_upto(struct frand_state *state, uint32_t end)
 {
 	uint32_t r;
 
 	assert(!state->use64);
 
 	r = __rand32(&state->state32);
-	return start + (int) ((double)end * (r / (FRAND32_MAX + 1.0)));
+	end++;
+	return (int) ((double)end * (r / (FRAND32_MAX + 1.0)));
 }
 
-static inline uint64_t rand64_between(struct frand_state *state, uint64_t start,
-				      uint64_t end)
+static inline uint64_t rand64_upto(struct frand_state *state, uint64_t end)
 {
 	uint64_t r;
 
+	assert(state->use64);
+
 	r = __rand64(&state->state64);
-	return start + (uint64_t) ((double)end * (r / (FRAND64_MAX + 1.0)));
+	end++;
+	return (uint64_t) ((double)end * (r / (FRAND64_MAX + 1.0)));
 }
 
+/*
+ * Generate a random value between 'start' and 'end', both inclusive
+ */
 static inline uint64_t rand_between(struct frand_state *state, uint64_t start,
 				    uint64_t end)
 {
 	if (state->use64)
-		return rand32_between(state, start, end);
+		return start + rand64_upto(state, end - start);
 	else
-		return rand64_between(state, start, end);
+		return start + rand32_upto(state, end - start);
 }
 
 extern void init_rand(struct frand_state *, bool);