diff options
Diffstat (limited to 'benchtests')
| -rw-r--r-- | benchtests/Makefile | 2 | ||||
| -rw-r--r-- | benchtests/bench-pthread-mutex-locks.c | 288 |
2 files changed, 290 insertions, 0 deletions
diff --git a/benchtests/Makefile b/benchtests/Makefile index 8dfca592fd..b477042e6c 100644 --- a/benchtests/Makefile +++ b/benchtests/Makefile @@ -102,6 +102,7 @@ endif bench-pthread := \ pthread-locks \ + pthread-mutex-locks \ pthread_once \ thread_create \ # bench-pthread @@ -281,6 +282,7 @@ $(addprefix $(objpfx)bench-,$(math-benchset)): $(libm-benchtests) $(addprefix $(objpfx)bench-,$(bench-pthread)): $(thread-library-benchtests) $(addprefix $(objpfx)bench-,$(bench-malloc)): $(thread-library-benchtests) $(addprefix $(objpfx)bench-,pthread-locks): $(libm-benchtests) +$(addprefix $(objpfx)bench-,pthread-mutex-locks): $(libm-benchtests) diff --git a/benchtests/bench-pthread-mutex-locks.c b/benchtests/bench-pthread-mutex-locks.c new file mode 100644 index 0000000000..1685b9dd1f --- /dev/null +++ b/benchtests/bench-pthread-mutex-locks.c @@ -0,0 +1,288 @@ +/* Measure mutex_lock for different threads and critical sections. + Copyright (C) 2022 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library 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 + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + <https://www.gnu.org/licenses/>. */ + +#define TEST_MAIN +#define TEST_NAME "pthread-mutex-locks" +#define TIMEOUT (20 * 60) + +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> +#include <math.h> +#include <pthread.h> +#include <sys/time.h> +#include <sys/sysinfo.h> +#include "bench-timing.h" +#include "json-lib.h" + +static pthread_mutex_t lock; +static pthread_mutexattr_t attr; +static pthread_barrier_t barrier; + +#define START_ITERS 1000 + +#pragma GCC push_options +#pragma GCC optimize(1) + +static int __attribute__ ((noinline)) fibonacci (int i) +{ + asm(""); + if (i > 2) + return fibonacci (i - 1) + fibonacci (i - 2); + return 10 + i; +} + +static void +do_filler (void) +{ + char buf1[512], buf2[512]; + int f = fibonacci (4); + memcpy (buf1, buf2, f); +} + +static void +do_filler_shared (void) +{ + static char buf1[512], buf2[512]; + int f = fibonacci (4); + memcpy (buf1, buf2, f); +} + +#pragma GCC pop_options + +#define UNIT_WORK_CRT do_filler_shared () +#define UNIT_WORK_NON_CRT do_filler () + +static inline void +critical_section (int length) +{ + for (int i = length; i >= 0; i--) + UNIT_WORK_CRT; +} + +static inline void +non_critical_section (int length) +{ + for (int i = length; i >= 0; i--) + UNIT_WORK_NON_CRT; +} + +typedef struct Worker_Params +{ + long iters; + int crt_len; + int non_crt_len; + timing_t duration; +} Worker_Params; + +static void * +worker (void *v) +{ + timing_t start, stop; + Worker_Params *p = (Worker_Params *) v; + long iters = p->iters; + int crt_len = p->crt_len; + int non_crt_len = p->non_crt_len; + + pthread_barrier_wait (&barrier); + TIMING_NOW (start); + while (iters--) + { + pthread_mutex_lock (&lock); + critical_section (crt_len); + pthread_mutex_unlock (&lock); + non_critical_section (non_crt_len); + } + TIMING_NOW (stop); + + TIMING_DIFF (p->duration, start, stop); + return NULL; +} + +static double +do_one_test (int num_threads, int crt_len, int non_crt_len, long iters) +{ + int i; + timing_t mean; + Worker_Params *p, params[num_threads]; + pthread_t threads[num_threads]; + + pthread_mutex_init (&lock, &attr); + pthread_barrier_init (&barrier, NULL, num_threads); + + for (i = 0; i < num_threads; i++) + { + p = ¶ms[i]; + p->iters = iters; + p->crt_len = crt_len; + p->non_crt_len = non_crt_len; + pthread_create (&threads[i], NULL, worker, (void *) p); + } + for (i = 0; i < num_threads; i++) + pthread_join (threads[i], NULL); + + pthread_mutex_destroy (&lock); + pthread_barrier_destroy (&barrier); + + mean = 0; + for (i = 0; i < num_threads; i++) + mean += params[i].duration; + mean /= num_threads; + return mean; +} + +#define RUN_COUNT 10 +#define MIN_TEST_SEC 0.01 + +static void +do_bench_one (const char *name, int num_threads, int crt_len, int non_crt_len, + json_ctx_t *js) +{ + timing_t cur; + struct timeval ts, te; + double tsd, ted, td; + long iters, iters_limit, total_iters; + timing_t curs[RUN_COUNT + 2]; + int i, j; + double mean, stdev; + + iters = START_ITERS; + iters_limit = LONG_MAX / 100; + + while (1) + { + gettimeofday (&ts, NULL); + cur = do_one_test (num_threads, crt_len, non_crt_len, iters); + gettimeofday (&te, NULL); + /* Make sure the test to run at least MIN_TEST_SEC. */ + tsd = ts.tv_sec + ts.tv_usec / 1000000.0; + ted = te.tv_sec + te.tv_usec / 1000000.0; + td = ted - tsd; + if (td >= MIN_TEST_SEC || iters >= iters_limit) + break; + + iters *= 10; + } + + curs[0] = cur; + for (i = 1; i < RUN_COUNT + 2; i++) + curs[i] = do_one_test (num_threads, crt_len, non_crt_len, iters); + + /* Sort the results so we can discard the fastest and slowest + times as outliers. */ + for (i = 0; i < RUN_COUNT + 1; i++) + for (j = i + 1; j < RUN_COUNT + 2; j++) + if (curs[i] > curs[j]) + { + timing_t temp = curs[i]; + curs[i] = curs[j]; + curs[j] = temp; + } + + /* Calculate mean and standard deviation. */ + mean = 0.0; + total_iters = iters * num_threads; + for (i = 1; i < RUN_COUNT + 1; i++) + mean += (double) curs[i] / (double) total_iters; + mean /= RUN_COUNT; + + stdev = 0.0; + for (i = 1; i < RUN_COUNT + 1; i++) + { + double s = (double) curs[i] / (double) total_iters - mean; + stdev += s * s; + } + stdev = sqrt (stdev / (RUN_COUNT - 1)); + + char buf[256]; + snprintf (buf, sizeof buf, "%s,non_crt_len=%d,crt_len=%d,threads=%d", name, + non_crt_len, crt_len, num_threads); + + json_attr_object_begin (js, buf); + + json_attr_double (js, "duration", (double) cur); + json_attr_double (js, "iterations", (double) total_iters); + json_attr_double (js, "mean", mean); + json_attr_double (js, "stdev", stdev); + json_attr_double (js, "min-outlier", + (double) curs[0] / (double) total_iters); + json_attr_double (js, "min", (double) curs[1] / (double) total_iters); + json_attr_double (js, "max", + (double) curs[RUN_COUNT] / (double) total_iters); + json_attr_double (js, "max-outlier", + (double) curs[RUN_COUNT + 1] / (double) total_iters); + + json_attr_object_end (js); +} + +#define TH_CONF_MAX 10 + +int +do_bench (void) +{ + int rv = 0; + json_ctx_t json_ctx; + int i, j, k; + int th_num, th_conf, nprocs; + int threads[TH_CONF_MAX]; + int crt_lens[] = { 0, 1, 2, 4, 8, 16, 32, 64, 128 }; + int non_crt_lens[] = { 1, 32, 128 }; + char name[128]; + + json_init (&json_ctx, 2, stdout); + json_attr_object_begin (&json_ctx, "pthread_mutex_locks"); + + /* The thread config begins from 1, and increases by 2x until nprocs. + We also wants to test over-saturation case (1.25*nprocs). */ + nprocs = get_nprocs (); + th_num = 1; + for (th_conf = 0; th_conf < (TH_CONF_MAX - 2) && th_num < nprocs; th_conf++) + { + threads[th_conf] = th_num; + th_num <<= 1; + } + threads[th_conf++] = nprocs; + threads[th_conf++] = nprocs + nprocs / 4; + + pthread_mutexattr_init (&attr); + pthread_mutexattr_settype (&attr, PTHREAD_MUTEX_ADAPTIVE_NP); + snprintf (name, sizeof name, "type=adaptive"); + + for (k = 0; k < (sizeof (non_crt_lens) / sizeof (int)); k++) + { + int non_crt_len = non_crt_lens[k]; + for (j = 0; j < (sizeof (crt_lens) / sizeof (int)); j++) + { + int crt_len = crt_lens[j]; + for (i = 0; i < th_conf; i++) + { + th_num = threads[i]; + do_bench_one (name, th_num, crt_len, non_crt_len, &json_ctx); + } + } + } + + json_attr_object_end (&json_ctx); + + return rv; +} + +#define TEST_FUNCTION do_bench () + +#include "../test-skeleton.c" |