[PATCH net-next v3 1/3] selftests/ptr_ring: add benchmark application for ptr_ring

From: Yunsheng Lin
Date: Thu Jul 01 2021 - 08:27:26 EST


Currently ptr_ring selftest is embedded within the virtio
selftest, which involves some specific virtio operation,
such as notifying and kicking.

As ptr_ring has been used by various subsystems, it deserves
it's owner selftest in order to benchmark different usecase
of ptr_ring, such as page pool and pfifo_fast qdisc.

So add a simple application to benchmark ptr_ring performance.
Currently two test mode is supported:
Mode 0: Both producing and consuming is done in a single thread,
it is called simple test mode in the test app.
Mode 1: Producing and consuming is done in different thread
concurrently, also known as SPSC(single-producer/
single-consumer) test.

The multi-producer/single-consumer test for pfifo_fast case is
not added yet, which can be added if using CAS atomic operation
to enable lockless multi-producer is proved to be better than
using r->producer_lock.

Signed-off-by: Yunsheng Lin <linyunsheng@xxxxxxxxxx>
---
V3: Remove timestamp sampling, use standard C library as much
as possible.
---
MAINTAINERS | 5 +
tools/testing/selftests/ptr_ring/Makefile | 6 +
tools/testing/selftests/ptr_ring/ptr_ring_test.c | 224 +++++++++++++++++++++++
tools/testing/selftests/ptr_ring/ptr_ring_test.h | 130 +++++++++++++
4 files changed, 365 insertions(+)
create mode 100644 tools/testing/selftests/ptr_ring/Makefile
create mode 100644 tools/testing/selftests/ptr_ring/ptr_ring_test.c
create mode 100644 tools/testing/selftests/ptr_ring/ptr_ring_test.h

diff --git a/MAINTAINERS b/MAINTAINERS
index cc375fd..1227022 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -14847,6 +14847,11 @@ F: drivers/net/phy/dp83640*
F: drivers/ptp/*
F: include/linux/ptp_cl*

+PTR RING BENCHMARK
+M: Yunsheng Lin <linyunsheng@xxxxxxxxxx>
+L: netdev@xxxxxxxxxxxxxxx
+F: tools/testing/selftests/ptr_ring/
+
PTRACE SUPPORT
M: Oleg Nesterov <oleg@xxxxxxxxxx>
S: Maintained
diff --git a/tools/testing/selftests/ptr_ring/Makefile b/tools/testing/selftests/ptr_ring/Makefile
new file mode 100644
index 0000000..346dea9
--- /dev/null
+++ b/tools/testing/selftests/ptr_ring/Makefile
@@ -0,0 +1,6 @@
+# SPDX-License-Identifier: GPL-2.0
+LDLIBS = -lpthread
+
+TEST_GEN_PROGS := ptr_ring_test
+
+include ../lib.mk
diff --git a/tools/testing/selftests/ptr_ring/ptr_ring_test.c b/tools/testing/selftests/ptr_ring/ptr_ring_test.c
new file mode 100644
index 0000000..4a5312f
--- /dev/null
+++ b/tools/testing/selftests/ptr_ring/ptr_ring_test.c
@@ -0,0 +1,224 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2021 HiSilicon Limited.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include <errno.h>
+#include <malloc.h>
+#include <stdbool.h>
+
+#include "ptr_ring_test.h"
+#include "../../../../include/linux/ptr_ring.h"
+
+#define MIN_RING_SIZE 2
+#define MAX_RING_SIZE 10000000
+
+static struct ptr_ring ring ____cacheline_aligned_in_smp;
+
+struct worker_info {
+ pthread_t tid;
+ int test_count;
+ bool error;
+};
+
+static void *produce_worker(void *arg)
+{
+ struct worker_info *info = arg;
+ unsigned long i = 0;
+ int ret;
+
+ while (++i <= info->test_count) {
+ while (__ptr_ring_full(&ring))
+ cpu_relax();
+
+ ret = __ptr_ring_produce(&ring, (void *)i);
+ if (ret) {
+ fprintf(stderr, "produce failed: %d\n", ret);
+ info->error = true;
+ return NULL;
+ }
+ }
+
+ info->error = false;
+
+ return NULL;
+}
+
+static void *consume_worker(void *arg)
+{
+ struct worker_info *info = arg;
+ unsigned long i = 0;
+ int *ptr;
+
+ while (++i <= info->test_count) {
+ while (__ptr_ring_empty(&ring))
+ cpu_relax();
+
+ ptr = __ptr_ring_consume(&ring);
+ if ((unsigned long)ptr != i) {
+ fprintf(stderr, "consumer failed, ptr: %lu, i: %lu\n",
+ (unsigned long)ptr, i);
+ info->error = true;
+ return NULL;
+ }
+ }
+
+ if (!__ptr_ring_empty(&ring)) {
+ fprintf(stderr, "ring should be empty, test failed\n");
+ info->error = true;
+ return NULL;
+ }
+
+ info->error = false;
+ return NULL;
+}
+
+/* test case for single producer single consumer */
+static void spsc_test(int size, int count)
+{
+ struct worker_info producer, consumer;
+ pthread_attr_t attr;
+ void *res;
+ int ret;
+
+ ret = ptr_ring_init(&ring, size, 0);
+ if (ret) {
+ fprintf(stderr, "init failed: %d\n", ret);
+ return;
+ }
+
+ producer.test_count = count;
+ consumer.test_count = count;
+
+ ret = pthread_attr_init(&attr);
+ if (ret) {
+ fprintf(stderr, "pthread attr init failed: %d\n", ret);
+ goto out;
+ }
+
+ ret = pthread_create(&producer.tid, &attr,
+ produce_worker, &producer);
+ if (ret) {
+ fprintf(stderr, "create producer thread failed: %d\n", ret);
+ goto out;
+ }
+
+ ret = pthread_create(&consumer.tid, &attr,
+ consume_worker, &consumer);
+ if (ret) {
+ fprintf(stderr, "create consumer thread failed: %d\n", ret);
+ goto out;
+ }
+
+ ret = pthread_join(producer.tid, &res);
+ if (ret) {
+ fprintf(stderr, "join producer thread failed: %d\n", ret);
+ goto out;
+ }
+
+ ret = pthread_join(consumer.tid, &res);
+ if (ret) {
+ fprintf(stderr, "join consumer thread failed: %d\n", ret);
+ goto out;
+ }
+
+ if (producer.error || consumer.error) {
+ fprintf(stderr, "spsc test failed\n");
+ goto out;
+ }
+
+ printf("ptr_ring(size:%d) perf spsc test produced/comsumed %d items, finished\n",
+ size, count);
+out:
+ ptr_ring_cleanup(&ring, NULL);
+}
+
+static void simple_test(int size, int count)
+{
+ struct timeval start, end;
+ int i = 0;
+ int *ptr;
+ int ret;
+
+ ret = ptr_ring_init(&ring, size, 0);
+ if (ret) {
+ fprintf(stderr, "init failed: %d\n", ret);
+ return;
+ }
+
+ while (++i <= count) {
+ ret = __ptr_ring_produce(&ring, &count);
+ if (ret) {
+ fprintf(stderr, "produce failed: %d\n", ret);
+ goto out;
+ }
+
+ ptr = __ptr_ring_consume(&ring);
+ if (ptr != &count) {
+ fprintf(stderr, "consume failed: %p\n", ptr);
+ goto out;
+ }
+ }
+
+ printf("ptr_ring(size:%d) perf simple test produced/consumed %d items, finished\n",
+ size, count);
+
+out:
+ ptr_ring_cleanup(&ring, NULL);
+}
+
+int main(int argc, char *argv[])
+{
+ int count = 1000000;
+ int size = 1000;
+ int mode = 0;
+ int opt;
+
+ while ((opt = getopt(argc, argv, "N:s:m:h")) != -1) {
+ switch (opt) {
+ case 'N':
+ count = atoi(optarg);
+ break;
+ case 's':
+ size = atoi(optarg);
+ break;
+ case 'm':
+ mode = atoi(optarg);
+ break;
+ case 'h':
+ printf("usage: ptr_ring_test [-N COUNT] [-s RING_SIZE] [-m TEST_MODE]\n");
+ return 0;
+ default:
+ return -1;
+ }
+ }
+
+ if (count <= 0) {
+ fprintf(stderr, "invalid test count, must be > 0\n");
+ return -1;
+ }
+
+ if (size < MIN_RING_SIZE || size > MAX_RING_SIZE) {
+ fprintf(stderr, "invalid ring size, must be in %d-%d\n",
+ MIN_RING_SIZE, MAX_RING_SIZE);
+ return -1;
+ }
+
+ switch (mode) {
+ case 0:
+ simple_test(size, count);
+ break;
+ case 1:
+ spsc_test(size, count);
+ break;
+ default:
+ fprintf(stderr, "invalid test mode\n");
+ return -1;
+ }
+
+ return 0;
+}
diff --git a/tools/testing/selftests/ptr_ring/ptr_ring_test.h b/tools/testing/selftests/ptr_ring/ptr_ring_test.h
new file mode 100644
index 0000000..32bfefb
--- /dev/null
+++ b/tools/testing/selftests/ptr_ring/ptr_ring_test.h
@@ -0,0 +1,130 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+
+#ifndef _TEST_PTR_RING_TEST_H
+#define _TEST_PTR_RING_TEST_H
+
+#include <assert.h>
+#include <stdatomic.h>
+#include <pthread.h>
+
+/* Assuming the cache line size is 64 for most cpu,
+ * change it accordingly if the running cpu has different
+ * cache line size in order to get more accurate result.
+ */
+#define SMP_CACHE_BYTES 64
+
+#define cpu_relax() sched_yield()
+#define smp_release() atomic_thread_fence(memory_order_release)
+#define smp_acquire() atomic_thread_fence(memory_order_acquire)
+#define smp_wmb() smp_release()
+#define smp_store_release(p, v) \
+ atomic_store_explicit(p, v, memory_order_release)
+
+#define READ_ONCE(x) (*(volatile typeof(x) *)&(x))
+#define WRITE_ONCE(x, val) ((*(volatile typeof(x) *)&(x)) = (val))
+#define cache_line_size SMP_CACHE_BYTES
+#define unlikely(x) (__builtin_expect(!!(x), 0))
+#define likely(x) (__builtin_expect(!!(x), 1))
+#define ALIGN(x, a) (((x) + (a) - 1) / (a) * (a))
+#define SIZE_MAX (~(size_t)0)
+#define KMALLOC_MAX_SIZE SIZE_MAX
+#define spinlock_t pthread_spinlock_t
+#define gfp_t int
+#define __GFP_ZERO 0x1
+
+#define ____cacheline_aligned_in_smp \
+ __attribute__((aligned(SMP_CACHE_BYTES)))
+
+static inline void *kmalloc(unsigned int size, gfp_t gfp)
+{
+ void *p;
+
+ p = memalign(64, size);
+ if (!p)
+ return p;
+
+ if (gfp & __GFP_ZERO)
+ memset(p, 0, size);
+
+ return p;
+}
+
+static inline void *kzalloc(unsigned int size, gfp_t flags)
+{
+ return kmalloc(size, flags | __GFP_ZERO);
+}
+
+static inline void *kmalloc_array(size_t n, size_t size, gfp_t flags)
+{
+ if (size != 0 && n > SIZE_MAX / size)
+ return NULL;
+ return kmalloc(n * size, flags);
+}
+
+static inline void *kcalloc(size_t n, size_t size, gfp_t flags)
+{
+ return kmalloc_array(n, size, flags | __GFP_ZERO);
+}
+
+static inline void kfree(void *p)
+{
+ free(p);
+}
+
+#define kvmalloc_array kmalloc_array
+#define kvfree kfree
+
+static inline void spin_lock_init(spinlock_t *lock)
+{
+ int r = pthread_spin_init(lock, 0);
+
+ assert(!r);
+}
+
+static inline void spin_lock(spinlock_t *lock)
+{
+ int ret = pthread_spin_lock(lock);
+
+ assert(!ret);
+}
+
+static inline void spin_unlock(spinlock_t *lock)
+{
+ int ret = pthread_spin_unlock(lock);
+
+ assert(!ret);
+}
+
+static inline void spin_lock_bh(spinlock_t *lock)
+{
+ spin_lock(lock);
+}
+
+static inline void spin_unlock_bh(spinlock_t *lock)
+{
+ spin_unlock(lock);
+}
+
+static inline void spin_lock_irq(spinlock_t *lock)
+{
+ spin_lock(lock);
+}
+
+static inline void spin_unlock_irq(spinlock_t *lock)
+{
+ spin_unlock(lock);
+}
+
+static inline void spin_lock_irqsave(spinlock_t *lock,
+ unsigned long f)
+{
+ spin_lock(lock);
+}
+
+static inline void spin_unlock_irqrestore(spinlock_t *lock,
+ unsigned long f)
+{
+ spin_unlock(lock);
+}
+
+#endif
--
2.7.4