A stress test program (works :)). So far not ported to Windows.
Signed-off-by: Paolo Bonzini <pbonz...@redhat.com>
---
rcutorture.c | 433 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
1 files changed, 433 insertions(+), 0 deletions(-)
create mode 100644 rcutorture.c
diff --git a/rcutorture.c b/rcutorture.c
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+++ b/rcutorture.c
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+/*
+ * rcutorture.h: simple user-level performance/stress test of RCU.
+ *
+ * Usage:
+ * ./rcu <nreaders> rperf [ <seconds> ]
+ * Run a read-side performance test with the specified
+ * number of readers for <seconds> seconds.
+ * Thus "./rcu 16 rperf 2" would run 16 readers on even-numbered
+ * CPUs from 0 to 30.
+ * ./rcu <nupdaters> uperf [ <seconds> ]
+ * Run an update-side performance test with the specified
+ * number of updaters and specified duration.
+ * ./rcu <nreaders> perf [ <seconds> ]
+ * Run a combined read/update performance test with the specified
+ * number of readers and one updater and specified duration.
+ *
+ * The above tests produce output as follows:
+ *
+ * n_reads: 46008000 n_updates: 146026 nreaders: 2 nupdaters: 1 duration: 1
+ * ns/read: 43.4707 ns/update: 6848.1
+ *
+ * The first line lists the total number of RCU reads and updates executed
+ * during the test, the number of reader threads, the number of updater
+ * threads, and the duration of the test in seconds. The second line
+ * lists the average duration of each type of operation in nanoseconds,
+ * or "nan" if the corresponding type of operation was not performed.
+ *
+ * ./rcu <nreaders> stress [ <seconds> ]
+ * Run a stress test with the specified number of readers and
+ * one updater. None of the threads are affinitied to any
+ * particular CPU.
+ *
+ * This test produces output as follows:
+ *
+ * n_reads: 114633217 n_updates: 3903415 n_mberror: 0
+ * rcu_stress_count: 114618391 14826 0 0 0 0 0 0 0 0 0
+ *
+ * The first line lists the number of RCU read and update operations
+ * executed, followed by the number of memory-ordering violations
+ * (which will be zero in a correct RCU implementation). The second
+ * line lists the number of readers observing progressively more stale
+ * data. A correct RCU implementation will have all but the first two
+ * numbers non-zero.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * 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 02111-1307, USA.
+ *
+ * Copyright (c) 2008 Paul E. McKenney, IBM Corporation.
+ */
+
+/*
+ * Test variables.
+ */
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <pthread.h>
+#include "rcu.h"
+#include "compiler.h"
+#include "qemu-thread.h"
+
+#include "qemu-thread-posix.c"
+#include "rcu.c"
+
+long long n_reads = 0LL;
+long n_updates = 0L;
+int nthreadsrunning;
+
+char argsbuf[64];
+
+#define GOFLAG_INIT 0
+#define GOFLAG_RUN 1
+#define GOFLAG_STOP 2
+
+volatile int goflag = GOFLAG_INIT;
+
+#define RCU_READ_RUN 1000
+
+#define NR_THREADS 100
+static pthread_t threads[NR_THREADS];
+
+static void create_thread(void *(*func)(void *), void *arg)
+{
+ pthread_t tid;
+ int i;
+
+ if (pthread_create(&tid, NULL, func, arg) != 0) {
+ perror("create_thread:pthread_create");
+ exit(-1);
+ }
+ for (i = 0; i < NR_THREADS; i++) {
+ if (__sync_bool_compare_and_swap(&threads[i], 0, tid))
+ break;
+ }
+ if (i >= NR_THREADS) {
+ fprintf(stderr, "Thread limit of %d exceeded!\n", NR_THREADS);
+ exit(-1);
+ }
+}
+
+static void wait_all_threads(void)
+{
+ int i;
+ void *vp;
+ pthread_t tid;
+
+ for (i = 1; i < NR_THREADS; i++) {
+ tid = threads[i];
+ if (tid != 0) {
+ if (pthread_join(tid, &vp) != 0) {
+ perror("wait_thread:pthread_join");
+ exit(-1);
+ }
+ threads[i] = 0;
+ }
+ }
+}
+
+/*
+ * Performance test.
+ */
+
+void *rcu_read_perf_test(void *arg)
+{
+ int i;
+ long long n_reads_local = 0;
+
+ rcu_register_thread();
+ __sync_fetch_and_add(&nthreadsrunning, 1);
+ rcu_thread_offline();
+ while (goflag == GOFLAG_INIT)
+ poll(NULL, 0, 1);
+ rcu_thread_online();
+ while (goflag == GOFLAG_RUN) {
+ for (i = 0; i < RCU_READ_RUN; i++) {
+ rcu_read_lock();
+ rcu_read_unlock();
+ }
+ n_reads_local += RCU_READ_RUN;
+ rcu_quiescent_state();
+ }
+ __sync_fetch_and_add(&n_reads, n_reads_local);
+ rcu_unregister_thread();
+
+ return (NULL);
+}
+
+void *rcu_update_perf_test(void *arg)
+{
+ long long n_updates_local = 0;
+
+ __sync_fetch_and_add(&nthreadsrunning, 1);
+ while (goflag == GOFLAG_INIT)
+ poll(NULL, 0, 1);
+ while (goflag == GOFLAG_RUN) {
+ synchronize_rcu();
+ n_updates_local++;
+ }
+ __sync_fetch_and_add(&n_updates, n_updates_local);
+ return NULL;
+}
+
+void perftestinit(void)
+{
+ nthreadsrunning = 0;
+}
+
+void perftestrun(int nthreads, int duration, int nreaders, int nupdaters)
+{
+ int t;
+
+ while (ACCESS_ONCE(nthreadsrunning) < nthreads)
+ poll(NULL, 0, 1);
+ goflag = GOFLAG_RUN;
+ sleep(duration);
+ goflag = GOFLAG_STOP;
+ wait_all_threads();
+ printf("n_reads: %lld n_updates: %ld nreaders: %d nupdaters: %d
duration: %d\n",
+ n_reads, n_updates, nreaders, nupdaters, duration);
+ printf("ns/read: %g ns/update: %g\n",
+ ((duration * 1000*1000*1000.*(double)nreaders) /
+ (double)n_reads),
+ ((duration * 1000*1000*1000.*(double)nupdaters) /
+ (double)n_updates));
+ exit(0);
+}
+
+void perftest(int nreaders, int duration)
+{
+ int i;
+
+ perftestinit();
+ for (i = 0; i < nreaders; i++) {
+ create_thread(rcu_read_perf_test, NULL);
+ }
+ create_thread(rcu_update_perf_test, NULL);
+ perftestrun(i + 1, duration, nreaders, 1);
+}
+
+void rperftest(int nreaders, int duration)
+{
+ int i;
+
+ perftestinit();
+ for (i = 0; i < nreaders; i++) {
+ create_thread(rcu_read_perf_test, NULL);
+ }
+ perftestrun(i, duration, nreaders, 0);
+}
+
+void uperftest(int nupdaters, int duration)
+{
+ int i;
+
+ perftestinit();
+ for (i = 0; i < nupdaters; i++) {
+ create_thread(rcu_update_perf_test, NULL);
+ }
+ perftestrun(i, duration, 0, nupdaters);
+}
+
+/*
+ * Stress test.
+ */
+
+#define RCU_STRESS_PIPE_LEN 10
+
+struct rcu_stress {
+ int pipe_count;
+ int mbtest;
+};
+
+struct rcu_stress rcu_stress_array[RCU_STRESS_PIPE_LEN] = { { 0 } };
+struct rcu_stress *rcu_stress_current;
+int rcu_stress_idx = 0;
+
+int n_mberror = 0;
+long long rcu_stress_count[RCU_STRESS_PIPE_LEN + 1];
+
+int garbage = 0;
+
+void *rcu_read_stress_test(void *arg)
+{
+ int i;
+ int itercnt = 0;
+ struct rcu_stress *p;
+ int pc;
+ long long n_reads_local;
+
+ rcu_register_thread();
+ rcu_thread_offline();
+ while (goflag == GOFLAG_INIT)
+ poll(NULL, 0, 1);
+ rcu_thread_online();
+ while (goflag == GOFLAG_RUN) {
+ rcu_read_lock();
+ p = rcu_dereference(rcu_stress_current);
+ if (p->mbtest == 0)
+ n_mberror++;
+ rcu_read_lock();
+ for (i = 0; i < 100; i++)
+ garbage++;
+ rcu_read_unlock();
+ pc = p->pipe_count;
+ rcu_read_unlock();
+ if ((pc > RCU_STRESS_PIPE_LEN) || (pc < 0))
+ pc = RCU_STRESS_PIPE_LEN;
+ __sync_fetch_and_add(&rcu_stress_count[pc], 1);
+ n_reads_local++;
+ rcu_quiescent_state();
+ if ((++itercnt % 0x1000) == 0) {
+ synchronize_rcu();
+ }
+ }
+ __sync_fetch_and_add(&n_reads, n_reads_local);
+ rcu_thread_offline();
+ rcu_unregister_thread();
+
+ return (NULL);
+}
+
+#if 0
+void rcu_update_stress_test_rcu(struct rcu_head *head)
+{
+ if (pthread_mutex_lock(&call_rcu_test_mutex) != 0) {
+ perror("pthread_mutex_lock");
+ exit(-1);
+ }
+ if (pthread_cond_signal(&call_rcu_test_cond) != 0) {
+ perror("pthread_cond_signal");
+ exit(-1);
+ }
+ if (pthread_mutex_unlock(&call_rcu_test_mutex) != 0) {
+ perror("pthread_mutex_unlock");
+ exit(-1);
+ }
+}
+#endif
+
+void *rcu_update_stress_test(void *arg)
+{
+ int i;
+ struct rcu_stress *p;
+#if 0
+ struct rcu_head rh;
+#endif
+
+ while (goflag == GOFLAG_INIT)
+ poll(NULL, 0, 1);
+ while (goflag == GOFLAG_RUN) {
+ i = rcu_stress_idx + 1;
+ if (i >= RCU_STRESS_PIPE_LEN)
+ i = 0;
+ p = &rcu_stress_array[i];
+ p->mbtest = 0;
+ __sync_synchronize();
+ p->pipe_count = 0;
+ p->mbtest = 1;
+ rcu_assign_pointer(rcu_stress_current, p);
+ rcu_stress_idx = i;
+ for (i = 0; i < RCU_STRESS_PIPE_LEN; i++)
+ if (i != rcu_stress_idx)
+ rcu_stress_array[i].pipe_count++;
+#if 0
+ if (n_updates & 0x1)
+ synchronize_rcu();
+ else {
+ if (pthread_mutex_lock(&call_rcu_test_mutex) != 0) {
+ perror("pthread_mutex_lock");
+ exit(-1);
+ }
+ call_rcu(&rh, rcu_update_stress_test_rcu);
+ if (pthread_cond_wait(&call_rcu_test_cond,
+ &call_rcu_test_mutex) != 0) {
+ perror("pthread_cond_wait");
+ exit(-1);
+ }
+ if (pthread_mutex_unlock(&call_rcu_test_mutex) != 0) {
+ perror("pthread_mutex_unlock");
+ exit(-1);
+ }
+ }
+#else
+ synchronize_rcu();
+#endif
+ n_updates++;
+ }
+ return NULL;
+}
+
+void *rcu_fake_update_stress_test(void *arg)
+{
+ while (goflag == GOFLAG_INIT)
+ poll(NULL, 0, 1);
+ while (goflag == GOFLAG_RUN) {
+ synchronize_rcu();
+ poll(NULL, 0, 1);
+ }
+ return NULL;
+}
+
+void stresstest(int nreaders, int duration)
+{
+ int i;
+ int t;
+ long long *p;
+ long long sum;
+
+ rcu_stress_current = &rcu_stress_array[0];
+ rcu_stress_current->pipe_count = 0;
+ rcu_stress_current->mbtest = 1;
+ for (i = 0; i < nreaders; i++)
+ create_thread(rcu_read_stress_test, NULL);
+ create_thread(rcu_update_stress_test, NULL);
+ for (i = 0; i < 5; i++)
+ create_thread(rcu_fake_update_stress_test, NULL);
+ goflag = GOFLAG_RUN;
+ sleep(duration);
+ goflag = GOFLAG_STOP;
+ wait_all_threads();
+ printf("n_reads: %lld n_updates: %ld n_mberror: %d\n",
+ n_reads, n_updates, n_mberror);
+ printf("rcu_stress_count:");
+ for (i = 0; i <= RCU_STRESS_PIPE_LEN; i++) {
+ printf(" %lld", rcu_stress_count[i]);
+ }
+ printf("\n");
+ exit(0);
+}
+
+/*
+ * Mainprogram.
+ */
+
+void usage(int argc, char *argv[])
+{
+ fprintf(stderr, "Usage: %s [nreaders [ perf | stress ] ]\n", argv[0]);
+ exit(-1);
+}
+
+int main(int argc, char *argv[])
+{
+ int nreaders = 1;
+ int duration = 1;
+
+ if (argc >= 2) {
+ nreaders = strtoul(argv[1], NULL, 0);
+ }
+ if (argc > 3) {
+ duration = strtoul(argv[3], NULL, 0);
+ }
+ if (argc < 3 || strcmp(argv[2], "stress") == 0)
+ stresstest(nreaders, duration);
+ else if (strcmp(argv[2], "rperf") == 0)
+ rperftest(nreaders, duration);
+ else if (strcmp(argv[2], "uperf") == 0)
+ uperftest(nreaders, duration);
+ else if (strcmp(argv[2], "perf") == 0)
+ perftest(nreaders, duration);
+ usage(argc, argv);
+ return 0;
+}
--
1.7.6
