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zdtm: make datagen/datachk faster for big chunks

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Generate random data only for buffers with sizes less than FAST_SIZE
If a size of buffer is more that FAST_SIZE, the first FAST_SIZE bytes
are filled by random generator and then this chunk is used as pattern
for all other chunks.

With out this patch:
$ time bash -x test/zdtm.sh static/maps04
real	0m16.777s
user	0m0.054s
sys	0m0.724s

With this patch:
$ time bash -x test/zdtm.sh static/maps04
real	0m1.865s
user	0m0.128s
sys	0m0.745s

Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
This commit is contained in:
Andrey Vagin
2013-03-06 00:34:02 +04:00
committed by Pavel Emelyanov
parent 28f063ab9c
commit a59fd3533f
1 changed files with 59 additions and 0 deletions
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59
test/zdtm/lib/datagen.c
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@@ -1,7 +1,60 @@
#include <stdlib.h>
#include <string.h>
#include "zdtmtst.h"
/*
* Generate random data only for buffers with sizes less than FAST_SIZE
* If a size of buffer is more than FAST_SIZE, the first FAST_SIZE bytes
* are filled by random generator and then this chunk is used as pattern
* for all other chunks.
*/
#define FAST_SIZE 99971 /* Prime number */
static void datagen_fast(uint8_t *buffer, unsigned length, uint32_t *crc)
{
uint8_t *p;
datagen(buffer, FAST_SIZE, crc);
p = buffer + FAST_SIZE;
while (p < buffer + length) {
unsigned long size = FAST_SIZE;
if (p + FAST_SIZE > buffer + length)
size = buffer + length - p;
memcpy(p, buffer, size);
p += FAST_SIZE;
}
}
static int datachk_fast(const uint8_t *buffer, unsigned length, uint32_t *crc)
{
const uint8_t *p;
if (datachk(buffer, FAST_SIZE, crc))
return 1;
p = buffer + FAST_SIZE;
while (p < buffer + length) {
unsigned long size = FAST_SIZE;
if (p + FAST_SIZE > buffer + length)
size = buffer + length - p;
if (memcmp(p, buffer, size)) {
test_msg("Memory corruption [%p, %p]\n", p, p + size);
return 1;
}
p += FAST_SIZE;
}
return 0;
}
/* update CRC-32 */
#define CRCPOLY 0xedb88320
static inline uint32_t crc32_le8(uint32_t crc, uint8_t datum)
@@ -18,6 +71,9 @@ void datagen(uint8_t *buffer, unsigned length, uint32_t *crc)
uint32_t rnd = 0;
unsigned shift;
if (length > FAST_SIZE)
return datagen_fast(buffer, length, crc);
for (shift = 0; length-- > 4; buffer++, shift--, rnd >>= 8) {
if (!shift) {
shift = 4;
@@ -58,6 +114,9 @@ int datachk(const uint8_t *buffer, unsigned length, uint32_t *crc)
{
uint32_t read_crc;
if (length > FAST_SIZE)
return datachk_fast(buffer, length, crc);
for (; length-- > 4; buffer++)
*crc = crc32_le8(*crc, *buffer);