From 7679325702c90aecd393cd7cde685576c14489c0 Mon Sep 17 00:00:00 2001 From: Barry Song Date: Mon, 16 Nov 2020 19:08:48 +1300 Subject: [PATCH] selftests/dma: add test application for DMA_MAP_BENCHMARK 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 Cc: Shuah Khan Cc: Christoph Hellwig Cc: Marek Szyprowski Cc: Robin Murphy Signed-off-by: Barry Song Signed-off-by: Christoph Hellwig --- MAINTAINERS | 6 ++ tools/testing/selftests/dma/Makefile | 6 ++ tools/testing/selftests/dma/config | 1 + tools/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 a008b70..c88abd1 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -5237,6 +5237,12 @@ F: include/linux/dma-mapping.h F: include/linux/dma-map-ops.h F: kernel/dma/ +DMA MAPPING BENCHMARK +M: Barry Song +L: iommu@lists.linux-foundation.org +F: kernel/dma/map_benchmark.c +F: tools/testing/selftests/dma/ + DMA-BUF HEAPS FRAMEWORK M: Sumit Semwal R: Benjamin Gaignard diff --git a/tools/testing/selftests/dma/Makefile b/tools/testing/selftests/dma/Makefile new file mode 100644 index 0000000..aa8e8b5 --- /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 0000000..6102ee3 --- /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 0000000..7065163 --- /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 +#include +#include +#include +#include +#include +#include + +#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; +} -- 2.7.4