This patch provides the test application for DMA_MAP_BENCHMARK.
Before running the test application, we need to bind a device to dma_map_
benchmark driver. For example, unbind "xxx" from its original driver and
bind to dma_map_benchmark:
echo dma_map_benchmark > /sys/bus/platform/devices/xxx/driver_override
echo xxx > /sys/bus/platform/drivers/xxx/unbind
echo xxx > /sys/bus/platform/drivers/dma_map_benchmark/bind
Another example for PCI devices:
echo dma_map_benchmark > /sys/bus/pci/devices/0000:00:01.0/driver_override
echo 0000:00:01.0 > /sys/bus/pci/drivers/xxx/unbind
echo 0000:00:01.0 > /sys/bus/pci/drivers/dma_map_benchmark/bind
The below command will run 16 threads on numa node 0 for 10 seconds on
the device bound to dma_map_benchmark platform_driver or pci_driver:
./dma_map_benchmark -t 16 -s 10 -n 0
dma mapping benchmark: threads:16 seconds:10
average map latency(us):1.1 standard deviation:1.9
average unmap latency(us):0.5 standard deviation:0.8
Cc: Will Deacon <will@xxxxxxxxxx>
Cc: Shuah Khan <shuah@xxxxxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxx>
Cc: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
Cc: Robin Murphy <robin.murphy@xxxxxxx>
Signed-off-by: Barry Song <song.bao.hua@xxxxxxxxxxxxx>
---
-v4:
* add dma direction and mask_bit parameters
MAINTAINERS | 6 +
tools/testing/selftests/dma/Makefile | 6 +
tools/testing/selftests/dma/config | 1 +
.../testing/selftests/dma/dma_map_benchmark.c | 123 ++++++++++++++++++
4 files changed, 136 insertions(+)
create mode 100644 tools/testing/selftests/dma/Makefile
create mode 100644 tools/testing/selftests/dma/config
create mode 100644 tools/testing/selftests/dma/dma_map_benchmark.c
diff --git a/MAINTAINERS b/MAINTAINERS
index e451dcce054f..bc851ffd3114 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -5247,6 +5247,12 @@ F: include/linux/dma-mapping.h
F: include/linux/dma-map-ops.h
F: kernel/dma/
+DMA MAPPING BENCHMARK
+M: Barry Song <song.bao.hua@xxxxxxxxxxxxx>
+L: iommu@xxxxxxxxxxxxxxxxxxxxxxxxxx
+F: kernel/dma/map_benchmark.c
+F: tools/testing/selftests/dma/
+
DMA-BUF HEAPS FRAMEWORK
M: Sumit Semwal <sumit.semwal@xxxxxxxxxx>
R: Benjamin Gaignard <benjamin.gaignard@xxxxxxxxxx>
diff --git a/tools/testing/selftests/dma/Makefile b/tools/testing/selftests/dma/Makefile
new file mode 100644
index 000000000000..aa8e8b5b3864
--- /dev/null
+++ b/tools/testing/selftests/dma/Makefile
@@ -0,0 +1,6 @@
+# SPDX-License-Identifier: GPL-2.0
+CFLAGS += -I../../../../usr/include/
+
+TEST_GEN_PROGS := dma_map_benchmark
+
+include ../lib.mk
diff --git a/tools/testing/selftests/dma/config b/tools/testing/selftests/dma/config
new file mode 100644
index 000000000000..6102ee3c43cd
--- /dev/null
+++ b/tools/testing/selftests/dma/config
@@ -0,0 +1 @@
+CONFIG_DMA_MAP_BENCHMARK=y
diff --git a/tools/testing/selftests/dma/dma_map_benchmark.c b/tools/testing/selftests/dma/dma_map_benchmark.c
new file mode 100644
index 000000000000..7065163a8388
--- /dev/null
+++ b/tools/testing/selftests/dma/dma_map_benchmark.c
@@ -0,0 +1,123 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2020 Hisilicon Limited.
+ */
+
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/ioctl.h>
+#include <sys/mman.h>
+#include <linux/types.h>
+
+#define DMA_MAP_BENCHMARK _IOWR('d', 1, struct map_benchmark)
+#define DMA_MAP_MAX_THREADS 1024
+#define DMA_MAP_MAX_SECONDS 300
+
+#define DMA_MAP_BIDIRECTIONAL 0
+#define DMA_MAP_TO_DEVICE 1
+#define DMA_MAP_FROM_DEVICE 2
+
+static char *directions[] = {
+ "BIDIRECTIONAL",
+ "TO_DEVICE",
+ "FROM_DEVICE",
+};
+
+struct map_benchmark {
+ __u64 avg_map_100ns; /* average map latency in 100ns */
+ __u64 map_stddev; /* standard deviation of map latency */
+ __u64 avg_unmap_100ns; /* as above */
+ __u64 unmap_stddev;
+ __u32 threads; /* how many threads will do map/unmap in parallel */
+ __u32 seconds; /* how long the test will last */
+ __s32 node; /* which numa node this benchmark will run on */
+ __u32 dma_bits; /* DMA addressing capability */
+ __u32 dma_dir; /* DMA data direction */
+ __u64 expansion[10]; /* For future use */
+};
+
+int main(int argc, char **argv)
+{
+ struct map_benchmark map;
+ int fd, opt;
+ /* default single thread, run 20 seconds on NUMA_NO_NODE */
+ int threads = 1, seconds = 20, node = -1;
+ /* default dma mask 32bit, bidirectional DMA */
+ int bits = 32, dir = DMA_MAP_BIDIRECTIONAL;
+
+ int cmd = DMA_MAP_BENCHMARK;
+ char *p;
+
+ while ((opt = getopt(argc, argv, "t:s:n:b:d:")) != -1) {
+ switch (opt) {
+ case 't':
+ threads = atoi(optarg);
+ break;
+ case 's':
+ seconds = atoi(optarg);
+ break;
+ case 'n':
+ node = atoi(optarg);
+ break;
+ case 'b':
+ bits = atoi(optarg);
+ break;
+ case 'd':
+ dir = atoi(optarg);
+ break;
+ default:
+ return -1;
+ }
+ }
+
+ if (threads <= 0 || threads > DMA_MAP_MAX_THREADS) {
+ fprintf(stderr, "invalid number of threads, must be in 1-%d\n",
+ DMA_MAP_MAX_THREADS);
+ exit(1);
+ }
+
+ if (seconds <= 0 || seconds > DMA_MAP_MAX_SECONDS) {
+ fprintf(stderr, "invalid number of seconds, must be in 1-%d\n",
+ DMA_MAP_MAX_SECONDS);
+ exit(1);
+ }
+
+ /* suppose the mininum DMA zone is 1MB in the world */
+ if (bits < 20 || bits > 64) {
+ fprintf(stderr, "invalid dma mask bit, must be in 20-64\n");
+ exit(1);
+ }
+
+ if (dir != DMA_MAP_BIDIRECTIONAL && dir != DMA_MAP_TO_DEVICE &&
+ dir != DMA_MAP_FROM_DEVICE) {
+ fprintf(stderr, "invalid dma direction\n");
+ exit(1);
+ }
+
+ fd = open("/sys/kernel/debug/dma_map_benchmark", O_RDWR);
+ if (fd == -1) {
+ perror("open");
+ exit(1);
+ }
+
+ map.seconds = seconds;
+ map.threads = threads;
+ map.node = node;
+ map.dma_bits = bits;
+ map.dma_dir = dir;
+ if (ioctl(fd, cmd, &map)) {
+ perror("ioctl");
+ exit(1);
+ }
+
+ printf("dma mapping benchmark: threads:%d seconds:%d node:%d dir:%s\n",
+ threads, seconds, node, dir[directions]);
+ printf("average map latency(us):%.1f standard deviation:%.1f\n",
+ map.avg_map_100ns/10.0, map.map_stddev/10.0);
+ printf("average unmap latency(us):%.1f standard deviation:%.1f\n",
+ map.avg_unmap_100ns/10.0, map.unmap_stddev/10.0);
+
+ return 0;
+}
--
2.25.1
