Re: [PATCH libdrm 6/9] tests/random: extract test out of xf86drmRandom.c

On Sun, 2015-03-22 at 22:03 +0000, Emil Velikov wrote:

With follow up commits we can clear it up and wire to make check

Signed-off-by: Emil Velikov emil.l.velikov@gmail.com

tests/Makefile.am | 3 +- tests/random.c | 127 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ xf86drmRandom.c | 67 ++-------------------------- 3 files changed, 132 insertions(+), 65 deletions(-) create mode 100644 tests/random.c

diff --git a/tests/Makefile.am b/tests/Makefile.am index 392abf5..9b13b2e 100644 --- a/tests/Makefile.am +++ b/tests/Makefile.am @@ -29,7 +29,8 @@ LDADD = $(top_builddir)/libdrm.la

check_PROGRAMS = \ dristat \

• drmstat

• drmstat \
• random

if HAVE_NOUVEAU SUBDIRS += nouveau diff --git a/tests/random.c b/tests/random.c new file mode 100644 index 0000000..6dc8386 --- /dev/null +++ b/tests/random.c @@ -0,0 +1,127 @@ +/* xf86drmRandom.c -- "Minimal Standard" PRNG Implementation

• • Created: Mon Apr 19 08:28:13 1999 by faith@precisioninsight.com
• • Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
• • All Rights Reserved.
• • Permission is hereby granted, free of charge, to any person obtaining a
• • copy of this software and associated documentation files (the "Software"),
• • to deal in the Software without restriction, including without limitation
• • the rights to use, copy, modify, merge, publish, distribute, sublicense,
• • and/or sell copies of the Software, and to permit persons to whom the
• • Software is furnished to do so, subject to the following conditions:
• • The above copyright notice and this permission notice (including the next
• • paragraph) shall be included in all copies or substantial portions of the
• • Software.
• • THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
• • IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
• • FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
• • PRECISION INSIGHT AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
• • OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
• • ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
• • DEALINGS IN THE SOFTWARE.
• • Authors: Rickard E. (Rik) Faith faith@valinux.com
• • DESCRIPTION
• • This file contains a simple, straightforward implementation of the Park
• • & Miller "Minimal Standard" PRNG [PM88, PMS93], which is a Lehmer
• • multiplicative linear congruential generator (MLCG) with a period of
• • 2^31-1.
• • This implementation is intended to provide a reliable, portable PRNG
• • that is suitable for testing a hash table implementation and for
• • implementing skip lists.
• • FUTURE ENHANCEMENTS
• • If initial seeds are not selected randomly, two instances of the PRNG
• • can be correlated. [Knuth81, pp. 32-33] describes a shuffling technique
• • that can eliminate this problem.
• • If PRNGs are used for simulation, the period of the current
• • implementation may be too short. [LE88] discusses methods of combining
• • MLCGs to produce much longer periods, and suggests some alternative
• • values for A and M. [LE90 and Sch92] also provide information on
• • long-period PRNGs.
• • REFERENCES
• • [Knuth81] Donald E. Knuth. The Art of Computer Programming. Volume 2:
• • Seminumerical Algorithms. Reading, Massachusetts: Addison-Wesley, 1981.
• • [LE88] Pierre L'Ecuyer. "Efficient and Portable Combined Random Number
• • Generators". CACM 31(6), June 1988, pp. 742-774.
• • [LE90] Pierre L'Ecuyer. "Random Numbers for Simulation". CACM 33(10,
• • October 1990, pp. 85-97.
• • [PM88] Stephen K. Park and Keith W. Miller. "Random Number Generators:
• • Good Ones are Hard to Find". CACM 31(10), October 1988, pp. 1192-1201.
• • [Sch92] Bruce Schneier. "Pseudo-Ransom Sequence Generator for 32-Bit
• • CPUs". Dr. Dobb's Journal 17(2), February 1992, pp. 34, 37-38, 40.
• • [PMS93] Stephen K. Park, Keith W. Miller, and Paul K. Stockmeyer. In
• • "Technical Correspondence: Remarks on Choosing and Implementing Random
• • Number Generators". CACM 36(7), July 1993, pp. 105-110.
• */

+#include <stdio.h> +#include <stdlib.h>

+#include "xf86drm.h"

+typedef struct RandomState {

• unsigned long magic;
• unsigned long a;
• unsigned long m;
• unsigned long q; /* m div a */
• unsigned long r; /* m mod a */
• unsigned long check;
• unsigned long seed;

+} RandomState;

I think this should also go to an internal header. Otherwise lgtm

+static void check_period(unsigned long seed) +{

• unsigned long count = 0;
• unsigned long initial;
• void *state;
• state = drmRandomCreate(seed);
• initial = drmRandom(state);
• ++count;
• while (initial != drmRandom(state)) {
• if (!++count) break;
• }
• printf("With seed of %10lu, period = %10lu (0x%08lx)\n",

•   seed, count, count);
  

• drmRandomDestroy(state);

+}

+int main(void) +{

• RandomState *state;
• int i;
• unsigned long rand;
• state = drmRandomCreate(1);
• for (i = 0; i < 10000; i++) {
• rand = drmRandom(state);
• }
• printf("After 10000 iterations: %lu (%lu expected): %s\n",

•   rand, state->check,
  

•   rand - state->check ? "*INCORRECT*" : "CORRECT");
  

• drmRandomDestroy(state);
• printf("Checking periods...\n");
• check_period(1);
• check_period(2);
• check_period(31415926);
• return 0;

+} diff --git a/xf86drmRandom.c b/xf86drmRandom.c index 94922ad..39f3c52 100644 --- a/xf86drmRandom.c +++ b/xf86drmRandom.c @@ -74,23 +74,11 @@ #include <stdio.h> #include <stdlib.h>

-#define RANDOM_MAIN 0

-#if !RANDOM_MAIN -# include "xf86drm.h" -#endif +#include "xf86drm.h"

#define RANDOM_MAGIC 0xfeedbeef #define RANDOM_DEBUG 0

-#if RANDOM_MAIN -#define RANDOM_ALLOC malloc -#define RANDOM_FREE free -#else -#define RANDOM_ALLOC drmMalloc -#define RANDOM_FREE drmFree -#endif

typedef struct RandomState { unsigned long magic; unsigned long a; @@ -101,18 +89,11 @@ typedef struct RandomState { unsigned long seed; } RandomState;

-#if RANDOM_MAIN -extern void *drmRandomCreate(unsigned long seed); -extern int drmRandomDestroy(void *state); -extern unsigned long drmRandom(void *state); -extern double drmRandomDouble(void *state); -#endif

void *drmRandomCreate(unsigned long seed) { RandomState *state;

• state = RANDOM_ALLOC(sizeof(*state));

• state = drmMalloc(sizeof(*state)); if (!state) return NULL; state->magic = RANDOM_MAGIC;

#if 0 @@ -140,7 +121,7 @@ void *drmRandomCreate(unsigned long seed)

int drmRandomDestroy(void *state) {

• RANDOM_FREE(state);

• drmFree(state); return 0;

}

@@ -164,45 +145,3 @@ double drmRandomDouble(void *state)

 return (double)drmRandom(state)/(double)s->m;

}

-#if RANDOM_MAIN -static void check_period(unsigned long seed) -{

• unsigned long count = 0;
• unsigned long initial;
• void *state;
• state = drmRandomCreate(seed);
• initial = drmRandom(state);
• ++count;
• while (initial != drmRandom(state)) {
• if (!++count) break;
• }
• printf("With seed of %10lu, period = %10lu (0x%08lx)\n",

•   seed, count, count);
  

• drmRandomDestroy(state);

-}

-int main(void) -{

• RandomState *state;
• int i;
• unsigned long rand;
• state = drmRandomCreate(1);
• for (i = 0; i < 10000; i++) {
• rand = drmRandom(state);
• }
• printf("After 10000 iterations: %lu (%lu expected): %s\n",

•   rand, state->check,
  

•   rand - state->check ? "*INCORRECT*" : "CORRECT");
  

• drmRandomDestroy(state);
• printf("Checking periods...\n");
• check_period(1);
• check_period(2);
• check_period(31415926);
• return 0;

-} -#endif