X-Git-Url: https://git.kernel.dk/?a=blobdiff_plain;f=lib%2Frand.c;h=a79fb9c17c321a94e8e4bcfe030193003c80d93f;hb=3e260a46ea9a8de224c3d0a29a608da3440f284a;hp=3b2d67ad6e9ebc4a242b24c162f94aa667a11743;hpb=2615cc4b28e7d0e436a625dff92e6a71ccc6c49b;p=fio.git

diff --git a/lib/rand.c b/lib/rand.c
index 3b2d67ad..a79fb9c1 100644
--- a/lib/rand.c
+++ b/lib/rand.c
@@ -33,11 +33,10 @@
 
 */
 
+#include <string.h>
 #include "rand.h"
 #include "../hash.h"
 
-struct frand_state __fio_rand_state;
-
 static inline int __seed(unsigned int x, unsigned int m)
 {
 	return (x < m) ? x + m : x;
@@ -79,13 +78,56 @@ void __fill_random_buf(void *buf, unsigned int len, unsigned long seed)
 	}
 }
 
-unsigned long fill_random_buf(void *buf, unsigned int len)
+unsigned long fill_random_buf(struct frand_state *fs, void *buf,
+			      unsigned int len)
 {
-	unsigned long r = __rand(&__fio_rand_state);
+	unsigned long r = __rand(fs);
 
 	if (sizeof(int) != sizeof(long *))
-		r *= (unsigned long) __rand(&__fio_rand_state);
+		r *= (unsigned long) __rand(fs);
 
 	__fill_random_buf(buf, len, r);
 	return r;
 }
+
+unsigned long fill_random_buf_percentage(struct frand_state *fs, void *buf,
+					 unsigned int percentage,
+					 unsigned int segment, unsigned int len)
+{
+	unsigned long r = __rand(fs);
+	unsigned int this_len;
+
+	if (percentage == 100) {
+		memset(buf, 0, len);
+		return 0;
+	}
+
+	if (segment > len)
+		segment = len;
+
+	if (sizeof(int) != sizeof(long *))
+		r *= (unsigned long) __rand(fs);
+
+	while (len) {
+		/*
+		 * Fill random chunk
+		 */
+		this_len = (segment * (100 - percentage)) / 100;
+		if (this_len > len)
+			this_len = len;
+
+		__fill_random_buf(buf, this_len, r);
+
+		len -= this_len;
+		buf += this_len;
+
+		if (this_len > len)
+			this_len = len;
+
+		memset(buf, 0, this_len);
+		len -= this_len;
+		buf += this_len;
+	}
+
+	return r;
+}