X-Git-Url: https://git.kernel.dk/?a=blobdiff_plain;ds=sidebyside;f=lib%2Fzipf.c;h=321a4fb9645e8995e1145758ec75530aeea75a16;hb=HEAD;hp=8b581fafff6e9e0dd8b1423d7e7d0b9e5e2d94de;hpb=8348daf915d4b2c3ec95a16ad803e9e42eb2bfda;p=fio.git

diff --git a/lib/zipf.c b/lib/zipf.c
index 8b581faf..14d7928f 100644
--- a/lib/zipf.c
+++ b/lib/zipf.c
@@ -1,12 +1,5 @@
 #include <math.h>
 #include <string.h>
-#include <inttypes.h>
-#include <stdio.h>
-#include <unistd.h>
-#include <sys/types.h>
-#include <fcntl.h>
-#include "ieee754.h"
-#include "../log.h"
 #include "zipf.h"
 #include "../minmax.h"
 #include "../hash.h"
@@ -15,7 +8,7 @@
 
 static void zipf_update(struct zipf_state *zs)
 {
-	unsigned long to_gen;
+	uint64_t to_gen;
 	unsigned int i;
 
 	/*
@@ -29,20 +22,22 @@ static void zipf_update(struct zipf_state *zs)
 		zs->zetan += pow(1.0 / (double) (i + 1), zs->theta);
 }
 
-static void shared_rand_init(struct zipf_state *zs, unsigned long nranges,
-			     unsigned int seed)
+static void shared_rand_init(struct zipf_state *zs, uint64_t nranges,
+			     double center, unsigned int seed)
 {
 	memset(zs, 0, sizeof(*zs));
 	zs->nranges = nranges;
 
 	init_rand_seed(&zs->rand, seed, 0);
 	zs->rand_off = __rand(&zs->rand);
+	if (center != -1)
+		zs->rand_off = nranges * center;
 }
 
-void zipf_init(struct zipf_state *zs, unsigned long nranges, double theta,
-	       unsigned int seed)
+void zipf_init(struct zipf_state *zs, uint64_t nranges, double theta,
+	       double center, unsigned int seed)
 {
-	shared_rand_init(zs, nranges, seed);
+	shared_rand_init(zs, nranges, center, seed);
 
 	zs->theta = theta;
 	zs->zeta2 = pow(1.0, zs->theta) + pow(0.5, zs->theta);
@@ -50,7 +45,7 @@ void zipf_init(struct zipf_state *zs, unsigned long nranges, double theta,
 	zipf_update(zs);
 }
 
-unsigned long long zipf_next(struct zipf_state *zs)
+uint64_t zipf_next(struct zipf_state *zs)
 {
 	double alpha, eta, rand_uni, rand_z;
 	unsigned long long n = zs->nranges;
@@ -69,28 +64,32 @@ unsigned long long zipf_next(struct zipf_state *zs)
 	else
 		val = 1 + (unsigned long long)(n * pow(eta*rand_uni - eta + 1.0, alpha));
 
+	val--;
+
 	if (!zs->disable_hash)
-		return (__hash_u64(val - 1) + zs->rand_off) % zs->nranges;
+		val = __hash_u64(val);
 
-	return (val - 1 + zs->rand_off) % zs->nranges;
+	return (val + zs->rand_off) % zs->nranges;
 }
 
-void pareto_init(struct zipf_state *zs, unsigned long nranges, double h,
-		 unsigned int seed)
+void pareto_init(struct zipf_state *zs, uint64_t nranges, double h,
+		 double center, unsigned int seed)
 {
-	shared_rand_init(zs, nranges, seed);
+	shared_rand_init(zs, nranges, center, seed);
 	zs->pareto_pow = log(h) / log(1.0 - h);
 }
 
-unsigned long long pareto_next(struct zipf_state *zs)
+uint64_t pareto_next(struct zipf_state *zs)
 {
 	double rand = (double) __rand(&zs->rand) / (double) FRAND32_MAX;
-	unsigned long long n = zs->nranges - 1;
+	unsigned long long n;
+
+	n = (zs->nranges - 1) * pow(rand, zs->pareto_pow);
 
 	if (!zs->disable_hash)
-		return (__hash_u64(n * pow(rand, zs->pareto_pow)) + zs->rand_off) % zs->nranges;
+		n = __hash_u64(n);
 
-	return (unsigned long long) (n * pow(rand, zs->pareto_pow) + zs->rand_off) % zs->nranges;
+	return (n + zs->rand_off)  % zs->nranges;
 }
 
 void zipf_disable_hash(struct zipf_state *zs)