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authorjaszha03 <jason.zhang2@arm.com>2019-07-01 17:20:52 -0500
committerDave Barach <openvpp@barachs.net>2019-07-31 13:55:12 +0000
commit25ab6cfed6db18bdd8cdb57b7e751751aa64c576 (patch)
tree030e0250238413e740953667f3017f5c64806e50 /src/vppinfra/test_rwlock.c
parent5cdde5c25a0e71d923a6d56e5c94e058887f95d8 (diff)
vppinfra: added performance test for clib_rwlock_t (test_rwlock.c)
Spawns a uniform number of writer and reader threads across a number of cores where each writer thread increments a global variable a specified number of times, and the reader threads continually poll the global's value until the writers complete. Type: test Change-Id: I979c3734c6d03139d0802bff1846875d226f6fbb Signed-off-by: Jason Zhang <jason.zhang2@arm.com> Reviewed-by: Honnappa Nagarahalli <honnappa.nagarahalli@arm.com> Reviewed-by: Lijian Zhang <Lijian.Zhang@arm.com>
Diffstat (limited to 'src/vppinfra/test_rwlock.c')
-rw-r--r--src/vppinfra/test_rwlock.c264
1 files changed, 264 insertions, 0 deletions
diff --git a/src/vppinfra/test_rwlock.c b/src/vppinfra/test_rwlock.c
new file mode 100644
index 00000000000..8b6f927d63e
--- /dev/null
+++ b/src/vppinfra/test_rwlock.c
@@ -0,0 +1,264 @@
+/*
+ * Copyright (c) 2019 Arm Limited.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE
+#endif
+
+#include <vppinfra/mem.h>
+#include <vppinfra/cache.h>
+#include <vppinfra/lock.h>
+#include <pthread.h>
+#include <vppinfra/format.h>
+#include <vppinfra/error.h>
+#include <vppinfra/time.h>
+#include <sched.h>
+#include <vppinfra/atomics.h>
+
+static u32 all_threads_online = 0;
+
+typedef struct
+{
+ uword threads_per_core;
+ uword cpu_mask_read;
+ uword read_cores;
+ uword cpu_mask_write;
+ uword write_cores;
+ uword increment_per_thread;
+ clib_rwlock_t rwlock;
+ uword shared_count;
+ uword iterations;
+} rwlock_test_main_t;
+
+void *
+write_shared_counter (void *arg)
+{
+ f64 *time = vec_new (f64, 1);
+ *time = 0;
+ rwlock_test_main_t *rtm = arg;
+
+ /* Wait for all threads to be created */
+ while (!clib_atomic_load_acq_n (&all_threads_online));
+
+ f64 start = clib_cpu_time_now ();
+ for (uword i = 0; i < rtm->increment_per_thread; i++)
+ {
+ clib_rwlock_writer_lock (&rtm->rwlock);
+ rtm->shared_count++;
+ clib_rwlock_writer_unlock (&rtm->rwlock);
+ }
+ *time = clib_cpu_time_now () - start;
+ return time;
+}
+
+void *
+read_shared_counter (void *arg)
+{
+ f64 *time = vec_new (f64, 1);
+ *time = 0;
+ rwlock_test_main_t *rtm = arg;
+ uword cnt_cpy = 0, exp = rtm->increment_per_thread * rtm->write_cores *
+ rtm->threads_per_core;
+
+ /* Wait for all threads to be created */
+ while (!clib_atomic_load_acq_n (&all_threads_online));
+
+ f64 start = clib_cpu_time_now ();
+ while (cnt_cpy < exp)
+ {
+ clib_rwlock_reader_lock (&rtm->rwlock);
+ cnt_cpy = rtm->shared_count;
+ clib_rwlock_reader_unlock (&rtm->rwlock);
+ }
+ *time = clib_cpu_time_now () - start;
+ return time;
+}
+
+unsigned
+test_rwlock (rwlock_test_main_t * rtm, f64 * elapse_time)
+{
+ int error = 0, total_threads = (rtm->read_cores + rtm->write_cores)
+ * rtm->threads_per_core;
+ pthread_t pthread[total_threads];
+
+ cpu_set_t cpuset;
+ unsigned cores_set = 0, cpu_id = 0;
+
+ /* Spawn reader (consumer) threads */
+ for (unsigned cpu_mask = rtm->cpu_mask_read; cpu_mask; cpu_mask >>= 1)
+ {
+ if (!(cpu_mask & 1))
+ {
+ cpu_id++;
+ continue;
+ }
+
+ CPU_ZERO (&cpuset);
+ CPU_SET (cpu_id, &cpuset);
+ for (uword t_num = 0; t_num < rtm->threads_per_core; t_num++)
+ {
+ uword t_index = cores_set * rtm->threads_per_core + t_num;
+ if (error = pthread_create (&pthread[t_index], NULL,
+ &read_shared_counter, rtm))
+ clib_unix_warning ("pthread_create failed with %d", error);
+
+ if (error = pthread_setaffinity_np (pthread[t_index],
+ sizeof (cpu_set_t), &cpuset))
+ clib_unix_warning ("pthread_set_affinity_np failed with %d",
+ error);
+ }
+ cores_set++;
+ cpu_id++;
+ }
+
+ /* Spawn writer (producer) threads */
+ cpu_id = 0;
+ for (unsigned cpu_mask = rtm->cpu_mask_write; cpu_mask; cpu_mask >>= 1)
+ {
+ if (!(cpu_mask & 1))
+ {
+ cpu_id++;
+ continue;
+ }
+
+ CPU_ZERO (&cpuset);
+ CPU_SET (cpu_id, &cpuset);
+ for (uword t_num = 0; t_num < rtm->threads_per_core; t_num++)
+ {
+ uword t_index = cores_set * rtm->threads_per_core + t_num;
+ if (error = pthread_create (&pthread[t_index], NULL,
+ &write_shared_counter, rtm))
+ clib_unix_warning ("pthread_create failed with %d", error);
+
+ if (error = pthread_setaffinity_np (pthread[t_index],
+ sizeof (cpu_set_t), &cpuset))
+ clib_unix_warning ("pthread_set_affinity_np failed with %d",
+ error);
+ }
+ cores_set++;
+ cpu_id++;
+ }
+
+ /* Launch all threads */
+ clib_atomic_store_rel_n (&all_threads_online, 1);
+
+ for (uword thread_num = 0; thread_num < total_threads; thread_num++)
+ {
+ f64 *time;
+ if (error = pthread_join (pthread[thread_num], (void *) &time))
+ clib_unix_warning ("pthread_join failed with %d", error);
+ *elapse_time += *time;
+ vec_free (time);
+ }
+
+ fformat (stdout, "Time elapsed: %.4e\n", *elapse_time);
+ return rtm->shared_count;
+}
+
+uword
+num_cores_in_cpu_mask (uword mask)
+{
+ uword num_cores = 0;
+ for (uword cpu_mask = mask; cpu_mask; cpu_mask >>= 1)
+ num_cores += (cpu_mask & 1);
+ return num_cores;
+}
+
+int
+test_rwlock_main (unformat_input_t * i)
+{
+ rwlock_test_main_t _rtm, *rtm = &_rtm;
+ clib_memset (rtm, 0, sizeof (rwlock_test_main_t));
+
+ while (unformat_check_input (i) != UNFORMAT_END_OF_INPUT)
+ {
+ if (0 == unformat (i, "threads/core %d", &rtm->threads_per_core)
+ && 0 == unformat (i, "cpu_mask_read %x", &rtm->cpu_mask_read)
+ && 0 == unformat (i, "cpu_mask_write %x", &rtm->cpu_mask_write)
+ && 0 == unformat (i, "increment %d", &rtm->increment_per_thread)
+ && 0 == unformat (i, "iterations %d", &rtm->iterations))
+ {
+ clib_unix_warning ("unknown input '%U'", format_unformat_error, i);
+ return 1;
+ }
+ }
+
+ rtm->read_cores = num_cores_in_cpu_mask (rtm->cpu_mask_read);
+ rtm->write_cores = num_cores_in_cpu_mask (rtm->cpu_mask_write);
+
+ uword total_increment = rtm->threads_per_core * rtm->write_cores *
+ rtm->increment_per_thread;
+
+ clib_rwlock_init (&rtm->rwlock);
+
+ f64 average_time = 0;
+ for (uword trial = 0; trial < rtm->iterations; trial++)
+ {
+ rtm->shared_count = 0;
+ f64 elapse_time = 0;
+ if (test_rwlock (rtm, &elapse_time) != total_increment)
+ {
+ clib_rwlock_free (&rtm->rwlock);
+ fformat (stdout, "FAILED: expected count: %d, actual count: %d\n",
+ total_increment, rtm->shared_count);
+ return 1;
+ }
+ fformat (stdout, "Trial %d SUCCESS: %d = %d\n",
+ trial, rtm->shared_count, total_increment);
+ average_time = (average_time * trial + elapse_time) / (trial + 1);
+ fformat (stdout, "Average lock/unlock cycles: %.4e\n", average_time);
+ }
+ clib_rwlock_free (&rtm->rwlock);
+ return 0;
+}
+
+#ifdef CLIB_UNIX
+/** Launches a number of writer threads to simultaneously increment a global
+ counter and a number of reader threads to continuously poll the counter,
+ and records timestamps for rwlock performance benchmarking
+
+ @param "threads/core [# threads/core]" - number of threads per core
+ @param "cpu_mask_read [cpu_mask]" - reader thread cpu string e.g. input
+ ff sets cpus 0 - 7
+ @param "cpu_mask_write [cpu_mask]" - writer thread cpu string
+ @param "increment [# increments]" - number of increments per writer thread
+ @param "iterations [# iterations]" - number of iterations
+ @returns exit code
+*/
+int
+main (int argc, char *argv[])
+{
+ unformat_input_t i;
+ i32 ret;
+ clib_time_t time;
+
+ clib_mem_init (0, 3ULL << 30);
+ clib_time_init (&time);
+
+ unformat_init_command_line (&i, argv);
+ ret = test_rwlock_main (&i);
+ unformat_free (&i);
+
+ return ret;
+}
+#endif /* CLIB_UNIX */
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */