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

在 2021/7/1 下午8:26, Yunsheng Lin 写道:

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@huawei.com

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@huawei.com +L: netdev@vger.kernel.org +F: tools/testing/selftests/ptr_ring/

• PTRACE SUPPORT M: Oleg Nesterov oleg@redhat.com 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();
  

Any reason for not simply use __ptr_ring_consume() here?

• 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

Let's reuse ptr_ring.c in tools/virtio/ringtest. Nothing virt specific there.

Thanks

@@ -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