X-Git-Url: https://git.kernel.dk/?a=blobdiff_plain;f=lib%2Frand.h;h=bff4a35167cbbfc95dc9258c54b5bbec3f1400e4;hb=b765bec0be97ef05e5af6cfbf4e0a2c8b7596a03;hp=a95bd28b49041991abb8a1713ad80c9ef086742a;hpb=592bf4581264dcb7959359a93bbddd46d12794ab;p=fio.git

diff --git a/lib/rand.h b/lib/rand.h
index a95bd28b..bff4a351 100644
--- a/lib/rand.h
+++ b/lib/rand.h
@@ -2,6 +2,8 @@
 #define FIO_RAND_H
 
 #include <inttypes.h>
+#include <assert.h>
+#include "types.h"
 #include "../arch/arch.h"
 
 #define FRAND32_MAX	(-1U)
@@ -23,10 +25,6 @@ struct frand_state {
 	};
 };
 
-struct frand64_state {
-	uint64_t s1, s2, s3, s4, s5;
-};
-
 static inline uint64_t rand_max(struct frand_state *state)
 {
 	if (state->use64)
@@ -117,8 +115,21 @@ static inline double __rand_0_1(struct frand_state *state)
 	}
 }
 
-extern void init_rand(struct frand_state *, int);
-extern void init_rand_seed(struct frand_state *, unsigned int seed, int);
+/*
+ * Generate a random value between 'start' and 'end', both inclusive
+ */
+static inline int rand32_between(struct frand_state *state, int start, int end)
+{
+	uint32_t r;
+
+	assert(!state->use64);
+
+	r = __rand32(&state->state32);
+	return start + (int) ((double)end * (r / (FRAND32_MAX + 1.0)));
+}
+
+extern void init_rand(struct frand_state *, bool);
+extern void init_rand_seed(struct frand_state *, unsigned int seed, bool);
 extern void __fill_random_buf(void *buf, unsigned int len, unsigned long seed);
 extern unsigned long fill_random_buf(struct frand_state *, void *buf, unsigned int len);
 extern void __fill_random_buf_percentage(unsigned long, void *, unsigned int, unsigned int, unsigned int, char *, unsigned int);