https://github.com/torvalds/linux
Tip revision: d9875690d9b89a866022ff49e3fcea892345ad92 authored by Linus Torvalds on 16 August 2012, 21:51:24 UTC
Linux 3.6-rc2
Linux 3.6-rc2
Tip revision: d987569
mem-memset.c
/*
* mem-memset.c
*
* memset: Simple memory set in various ways
*
* Trivial clone of mem-memcpy.c.
*/
#include "../perf.h"
#include "../util/util.h"
#include "../util/parse-options.h"
#include "../util/header.h"
#include "bench.h"
#include "mem-memset-arch.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/time.h>
#include <errno.h>
#define K 1024
static const char *length_str = "1MB";
static const char *routine = "default";
static int iterations = 1;
static bool use_cycle;
static int cycle_fd;
static bool only_prefault;
static bool no_prefault;
static const struct option options[] = {
OPT_STRING('l', "length", &length_str, "1MB",
"Specify length of memory to set. "
"Available units: B, KB, MB, GB and TB (upper and lower)"),
OPT_STRING('r', "routine", &routine, "default",
"Specify routine to set"),
OPT_INTEGER('i', "iterations", &iterations,
"repeat memset() invocation this number of times"),
OPT_BOOLEAN('c', "cycle", &use_cycle,
"Use cycles event instead of gettimeofday() for measuring"),
OPT_BOOLEAN('o', "only-prefault", &only_prefault,
"Show only the result with page faults before memset()"),
OPT_BOOLEAN('n', "no-prefault", &no_prefault,
"Show only the result without page faults before memset()"),
OPT_END()
};
typedef void *(*memset_t)(void *, int, size_t);
struct routine {
const char *name;
const char *desc;
memset_t fn;
};
static const struct routine routines[] = {
{ "default",
"Default memset() provided by glibc",
memset },
#ifdef ARCH_X86_64
#define MEMSET_FN(fn, name, desc) { name, desc, fn },
#include "mem-memset-x86-64-asm-def.h"
#undef MEMSET_FN
#endif
{ NULL,
NULL,
NULL }
};
static const char * const bench_mem_memset_usage[] = {
"perf bench mem memset <options>",
NULL
};
static struct perf_event_attr cycle_attr = {
.type = PERF_TYPE_HARDWARE,
.config = PERF_COUNT_HW_CPU_CYCLES
};
static void init_cycle(void)
{
cycle_fd = sys_perf_event_open(&cycle_attr, getpid(), -1, -1, 0);
if (cycle_fd < 0 && errno == ENOSYS)
die("No CONFIG_PERF_EVENTS=y kernel support configured?\n");
else
BUG_ON(cycle_fd < 0);
}
static u64 get_cycle(void)
{
int ret;
u64 clk;
ret = read(cycle_fd, &clk, sizeof(u64));
BUG_ON(ret != sizeof(u64));
return clk;
}
static double timeval2double(struct timeval *ts)
{
return (double)ts->tv_sec +
(double)ts->tv_usec / (double)1000000;
}
static void alloc_mem(void **dst, size_t length)
{
*dst = zalloc(length);
if (!dst)
die("memory allocation failed - maybe length is too large?\n");
}
static u64 do_memset_cycle(memset_t fn, size_t len, bool prefault)
{
u64 cycle_start = 0ULL, cycle_end = 0ULL;
void *dst = NULL;
int i;
alloc_mem(&dst, len);
if (prefault)
fn(dst, -1, len);
cycle_start = get_cycle();
for (i = 0; i < iterations; ++i)
fn(dst, i, len);
cycle_end = get_cycle();
free(dst);
return cycle_end - cycle_start;
}
static double do_memset_gettimeofday(memset_t fn, size_t len, bool prefault)
{
struct timeval tv_start, tv_end, tv_diff;
void *dst = NULL;
int i;
alloc_mem(&dst, len);
if (prefault)
fn(dst, -1, len);
BUG_ON(gettimeofday(&tv_start, NULL));
for (i = 0; i < iterations; ++i)
fn(dst, i, len);
BUG_ON(gettimeofday(&tv_end, NULL));
timersub(&tv_end, &tv_start, &tv_diff);
free(dst);
return (double)((double)len / timeval2double(&tv_diff));
}
#define pf (no_prefault ? 0 : 1)
#define print_bps(x) do { \
if (x < K) \
printf(" %14lf B/Sec", x); \
else if (x < K * K) \
printf(" %14lfd KB/Sec", x / K); \
else if (x < K * K * K) \
printf(" %14lf MB/Sec", x / K / K); \
else \
printf(" %14lf GB/Sec", x / K / K / K); \
} while (0)
int bench_mem_memset(int argc, const char **argv,
const char *prefix __used)
{
int i;
size_t len;
double result_bps[2];
u64 result_cycle[2];
argc = parse_options(argc, argv, options,
bench_mem_memset_usage, 0);
if (use_cycle)
init_cycle();
len = (size_t)perf_atoll((char *)length_str);
result_cycle[0] = result_cycle[1] = 0ULL;
result_bps[0] = result_bps[1] = 0.0;
if ((s64)len <= 0) {
fprintf(stderr, "Invalid length:%s\n", length_str);
return 1;
}
/* same to without specifying either of prefault and no-prefault */
if (only_prefault && no_prefault)
only_prefault = no_prefault = false;
for (i = 0; routines[i].name; i++) {
if (!strcmp(routines[i].name, routine))
break;
}
if (!routines[i].name) {
printf("Unknown routine:%s\n", routine);
printf("Available routines...\n");
for (i = 0; routines[i].name; i++) {
printf("\t%s ... %s\n",
routines[i].name, routines[i].desc);
}
return 1;
}
if (bench_format == BENCH_FORMAT_DEFAULT)
printf("# Copying %s Bytes ...\n\n", length_str);
if (!only_prefault && !no_prefault) {
/* show both of results */
if (use_cycle) {
result_cycle[0] =
do_memset_cycle(routines[i].fn, len, false);
result_cycle[1] =
do_memset_cycle(routines[i].fn, len, true);
} else {
result_bps[0] =
do_memset_gettimeofday(routines[i].fn,
len, false);
result_bps[1] =
do_memset_gettimeofday(routines[i].fn,
len, true);
}
} else {
if (use_cycle) {
result_cycle[pf] =
do_memset_cycle(routines[i].fn,
len, only_prefault);
} else {
result_bps[pf] =
do_memset_gettimeofday(routines[i].fn,
len, only_prefault);
}
}
switch (bench_format) {
case BENCH_FORMAT_DEFAULT:
if (!only_prefault && !no_prefault) {
if (use_cycle) {
printf(" %14lf Cycle/Byte\n",
(double)result_cycle[0]
/ (double)len);
printf(" %14lf Cycle/Byte (with prefault)\n ",
(double)result_cycle[1]
/ (double)len);
} else {
print_bps(result_bps[0]);
printf("\n");
print_bps(result_bps[1]);
printf(" (with prefault)\n");
}
} else {
if (use_cycle) {
printf(" %14lf Cycle/Byte",
(double)result_cycle[pf]
/ (double)len);
} else
print_bps(result_bps[pf]);
printf("%s\n", only_prefault ? " (with prefault)" : "");
}
break;
case BENCH_FORMAT_SIMPLE:
if (!only_prefault && !no_prefault) {
if (use_cycle) {
printf("%lf %lf\n",
(double)result_cycle[0] / (double)len,
(double)result_cycle[1] / (double)len);
} else {
printf("%lf %lf\n",
result_bps[0], result_bps[1]);
}
} else {
if (use_cycle) {
printf("%lf\n", (double)result_cycle[pf]
/ (double)len);
} else
printf("%lf\n", result_bps[pf]);
}
break;
default:
/* reaching this means there's some disaster: */
die("unknown format: %d\n", bench_format);
break;
}
return 0;
}