btrfs-progs/crypto/hash-speedtest.c
David Sterba 03f41ac508 btrfs-progs: detect PCLMUL CPU support for accelerated crc32c
The accelerated crc32c needs to check for two CPU features, the crc32c
instructions is in SSE 4.2 and 'pclmulqdq' is a separate. There's still
old hardware used that does not have the PCLMUL instructions. Detect it
and make it the condition.

The pclmul is not supported on old compilers so also add a
configure-time detection and leave the SSE 4.2 only implementation as
the accelerated one if possible.

Issue: #676
Signed-off-by: David Sterba <dsterba@suse.com>
2023-09-13 00:38:50 +02:00

333 lines
8.3 KiB
C

/*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public
* License v2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public
* License along with this program; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 021110-1307, USA.
*/
#include "kerncompat.h"
#include <time.h>
#include <getopt.h>
#include <unistd.h>
#if HAVE_LINUX_PERF_EVENT_H == 1 && HAVE_LINUX_HW_BREAKPOINT_H == 1
#include <linux/perf_event.h>
#include <linux/hw_breakpoint.h>
#include <sys/syscall.h>
#define HAVE_PERF
#endif
#include "crypto/hash.h"
#include "crypto/crc32c.h"
#include "crypto/sha.h"
#include "crypto/blake2.h"
#include "common/messages.h"
#include "common/cpu-utils.h"
#ifdef __x86_64__
static const int cycles_supported = 1;
#else
static const int cycles_supported = 0;
#endif
enum {
UNITS_CYCLES,
UNITS_TIME,
UNITS_PERF,
};
const int blocksize = 4096;
int iterations = 100000;
#ifdef __x86_64__
static __always_inline unsigned long long rdtsc(void)
{
unsigned low, high;
asm volatile("rdtsc" : "=a" (low), "=d" (high));
return (low | ((u64)(high) << 32));
}
static inline u64 read_tsc(void)
{
asm volatile("mfence");
return rdtsc();
}
#define cpu_cycles() read_tsc()
#else
#define cpu_cycles() (0)
#endif
#ifdef HAVE_PERF
static int perf_fd = -1;
static int perf_init(void)
{
static struct perf_event_attr attr = {
.type = PERF_TYPE_HARDWARE,
.config = PERF_COUNT_HW_CPU_CYCLES
};
perf_fd = syscall(__NR_perf_event_open, &attr, 0, -1, -1, 0);
return perf_fd;
}
static void perf_finish(void)
{
close(perf_fd);
}
static long long perf_cycles(void)
{
long long cycles;
int ret;
ret = read(perf_fd, &cycles, sizeof(cycles));
if (ret != sizeof(cycles))
return 0;
return cycles;
}
#else
static int perf_init()
{
errno = EOPNOTSUPP;
return -1;
}
static void perf_finish() {}
static long long perf_cycles() {
return 0;
}
#endif
static inline u64 get_time(void)
{
struct timespec ts;
clock_gettime(CLOCK_MONOTONIC, &ts);
return ts.tv_sec * 1000 * 1000 * 1000 + ts.tv_nsec;
}
static inline u64 get_cycles(int units)
{
switch (units) {
case UNITS_CYCLES: return cpu_cycles();
case UNITS_TIME: return get_time();
case UNITS_PERF: return perf_cycles();
}
return 0;
}
/* Read the input and copy last bytes as the hash */
static int hash_null_memcpy(const u8 *buf, size_t length, u8 *out)
{
const u8 *end = buf + length;
while (buf + CRYPTO_HASH_SIZE_MAX < end) {
memcpy(out, buf, CRYPTO_HASH_SIZE_MAX);
buf += CRYPTO_HASH_SIZE_MAX;
}
return 0;
}
/* Test overhead of the calls */
static int hash_null_nop(const u8 *buf, size_t length, u8 *out)
{
memset(out, 0xFF, CRYPTO_HASH_SIZE_MAX);
return 0;
}
static const char *units_to_desc(int units)
{
switch (units) {
case UNITS_CYCLES: return "CPU cycles";
case UNITS_TIME: return "time: ns";
case UNITS_PERF: return "perf event: CPU cycles";
}
return "unknown";
}
static const char *units_to_str(int units)
{
switch (units) {
case UNITS_CYCLES: return "cycles";
case UNITS_TIME: return "nsecs";
case UNITS_PERF: return "perf_c";
}
return "unknown";
}
int main(int argc, char **argv) {
u8 buf[blocksize];
u8 hash[32];
int idx;
int iter;
struct contestant {
char name[16];
int (*digest)(const u8 *buf, size_t length, u8 *out);
int digest_size;
u64 cycles;
u64 time;
unsigned long cpu_flag;
int backend;
} contestants[] = {
{ .name = "NULL-NOP", .digest = hash_null_nop, .digest_size = 32 },
{ .name = "NULL-MEMCPY", .digest = hash_null_memcpy, .digest_size = 32 },
{ .name = "CRC32C-ref", .digest = hash_crc32c, .digest_size = 4,
.cpu_flag = CPU_FLAG_NONE },
{ .name = "CRC32C-NI", .digest = hash_crc32c, .digest_size = 4,
.cpu_flag = CPU_FLAG_PCLMUL },
{ .name = "XXHASH", .digest = hash_xxhash, .digest_size = 8 },
{ .name = "SHA256-ref", .digest = hash_sha256, .digest_size = 32,
.cpu_flag = CPU_FLAG_NONE, .backend = CRYPTOPROVIDER_BUILTIN + 1 },
{ .name = "SHA256-gcrypt", .digest = hash_sha256, .digest_size = 32,
.cpu_flag = CPU_FLAG_NONE, .backend = CRYPTOPROVIDER_LIBGCRYPT + 1 },
{ .name = "SHA256-sodium", .digest = hash_sha256, .digest_size = 32,
.cpu_flag = CPU_FLAG_NONE, .backend = CRYPTOPROVIDER_LIBSODIUM + 1 },
{ .name = "SHA256-kcapi", .digest = hash_sha256, .digest_size = 32,
.cpu_flag = CPU_FLAG_NONE, .backend = CRYPTOPROVIDER_LIBKCAPI + 1 },
{ .name = "SHA256-NI", .digest = hash_sha256, .digest_size = 32,
.cpu_flag = CPU_FLAG_SHA, .backend = CRYPTOPROVIDER_BUILTIN + 1 },
{ .name = "BLAKE2-ref", .digest = hash_blake2b, .digest_size = 32,
.cpu_flag = CPU_FLAG_NONE, .backend = CRYPTOPROVIDER_BUILTIN + 1 },
{ .name = "BLAKE2-gcrypt", .digest = hash_blake2b, .digest_size = 32,
.cpu_flag = CPU_FLAG_NONE, .backend = CRYPTOPROVIDER_LIBGCRYPT + 1 },
{ .name = "BLAKE2-sodium", .digest = hash_blake2b, .digest_size = 32,
.cpu_flag = CPU_FLAG_NONE, .backend = CRYPTOPROVIDER_LIBSODIUM + 1 },
{ .name = "BLAKE2-kcapi", .digest = hash_blake2b, .digest_size = 32,
.cpu_flag = CPU_FLAG_NONE, .backend = CRYPTOPROVIDER_LIBKCAPI + 1 },
{ .name = "BLAKE2-SSE2", .digest = hash_blake2b, .digest_size = 32,
.cpu_flag = CPU_FLAG_SSE2, .backend = CRYPTOPROVIDER_BUILTIN + 1 },
{ .name = "BLAKE2-SSE41", .digest = hash_blake2b, .digest_size = 32,
.cpu_flag = CPU_FLAG_SSE41, .backend = CRYPTOPROVIDER_BUILTIN + 1 },
{ .name = "BLAKE2-AVX2", .digest = hash_blake2b, .digest_size = 32,
.cpu_flag = CPU_FLAG_AVX2, .backend = CRYPTOPROVIDER_BUILTIN + 1 },
};
int units = UNITS_CYCLES;
cpu_detect_flags();
cpu_print_flags();
hash_init_accel();
optind = 0;
while (1) {
static const struct option long_options[] = {
{ "cycles", no_argument, NULL, 'c' },
{ "time", no_argument, NULL, 't' },
{ "perf", no_argument, NULL, 'p' },
{ NULL, 0, NULL, 0}
};
int c;
c = getopt_long(argc, argv, "ctp", long_options, NULL);
if (c < 0)
break;
switch (c) {
case 'c':
if (!cycles_supported) {
error("cannot measure cycles on this arch, use --time");
return 1;
}
units = UNITS_CYCLES;
break;
case 't':
units = UNITS_TIME;
break;
case 'p':
if (perf_init() == -1) {
error(
"cannot initialize perf, please check sysctl kernel.perf_event_paranoid: %m");
return 1;
}
units = UNITS_PERF;
break;
default:
error("unknown option");
return 1;
}
}
if (argc - optind >= 1) {
iterations = atoi(argv[optind]);
if (iterations < 0)
iterations = 1;
}
memset(buf, 0, 4096);
printf("Block size: %d\n", blocksize);
printf("Iterations: %d\n", iterations);
printf("Implementation: %s\n", CRYPTOPROVIDER);
printf("Units: %s\n", units_to_desc(units));
printf("\n");
for (idx = 0; idx < ARRAY_SIZE(contestants); idx++) {
struct contestant *c = &contestants[idx];
u64 start, end;
u64 tstart, tend;
u64 total = 0;
if (c->cpu_flag != 0 && !cpu_has_feature(c->cpu_flag)) {
printf("%14s: no CPU support\n", c->name);
continue;
}
/* Backend not compiled in */
if (c->backend == 1)
continue;
printf("%14s: ", c->name);
fflush(stdout);
if (c->cpu_flag) {
cpu_set_level(c->cpu_flag);
hash_init_accel();
}
tstart = get_time();
start = get_cycles(units);
for (iter = 0; iter < iterations; iter++) {
memset(buf, iter & 0xFF, blocksize);
memset(hash, 0, 32);
c->digest(buf, blocksize, hash);
}
end = get_cycles(units);
tend = get_time();
c->cycles = end - start;
c->time = tend - tstart;
cpu_reset_level();
if (units == UNITS_CYCLES || units == UNITS_PERF)
total = c->cycles;
if (units == UNITS_TIME)
total = c->time;
printf("%s: %12llu, %s/i %8llu",
units_to_str(units), total,
units_to_str(units), total / iterations);
if (idx > 0) {
float t;
float mb;
t = (float)c->time / 1000 / 1000 / 1000;
mb = blocksize * iterations / 1024 / 1024;
printf(", %12.3f MiB/s", mb / t);
}
putchar('\n');
}
perf_finish();
return 0;
}