linux/tools/testing/selftests/dma/dma_map_benchmark.c
Xiang Chen ca947482b0 dma-mapping: benchmark: Add support for multi-pages map/unmap
Currently it only support one page map/unmap once a time for dma-map
benchmark, but there are some other scenaries which need to support for
multi-page map/unmap: for those multi-pages interfaces such as
dma_alloc_coherent() and dma_map_sg(), the time spent on multi-pages
map/unmap is not the time of a single page * npages (not linear) as it
may use block description instead of page description when it is satified
with the size such as 2M/1G, and also it can send a single TLB invalidation
command to invalidate multi-pages instead of multi-times when RIL is
enabled (which will short the time of unmap). So it is necessary to add
support for multi-pages map/unmap.

Add a parameter "-g" to support multi-pages map/unmap.

Signed-off-by: Xiang Chen <chenxiang66@hisilicon.com>
Acked-by: Barry Song <song.bao.hua@hisilicon.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-04-02 16:41:08 +02:00

153 lines
3.7 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2020 HiSilicon Limited.
*/
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <linux/types.h>
#define NSEC_PER_MSEC 1000000L
#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_MAX_TRANS_DELAY (10 * NSEC_PER_MSEC)
#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 */
__u32 dma_trans_ns; /* time for DMA transmission in ns */
__u32 granule; /* how many PAGE_SIZE will do map/unmap once a time */
__u8 expansion[76]; /* 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, xdelay = 0, dir = DMA_MAP_BIDIRECTIONAL;
/* default granule 1 PAGESIZE */
int granule = 1;
int cmd = DMA_MAP_BENCHMARK;
char *p;
while ((opt = getopt(argc, argv, "t:s:n:b:d:x:g:")) != -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;
case 'x':
xdelay = atoi(optarg);
break;
case 'g':
granule = 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);
}
if (xdelay < 0 || xdelay > DMA_MAP_MAX_TRANS_DELAY) {
fprintf(stderr, "invalid transmit delay, must be in 0-%ld\n",
DMA_MAP_MAX_TRANS_DELAY);
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);
}
if (granule < 1 || granule > 1024) {
fprintf(stderr, "invalid granule size\n");
exit(1);
}
fd = open("/sys/kernel/debug/dma_map_benchmark", O_RDWR);
if (fd == -1) {
perror("open");
exit(1);
}
memset(&map, 0, sizeof(map));
map.seconds = seconds;
map.threads = threads;
map.node = node;
map.dma_bits = bits;
map.dma_dir = dir;
map.dma_trans_ns = xdelay;
map.granule = granule;
if (ioctl(fd, cmd, &map)) {
perror("ioctl");
exit(1);
}
printf("dma mapping benchmark: threads:%d seconds:%d node:%d dir:%s granule: %d\n",
threads, seconds, node, dir[directions], granule);
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;
}