> -----Original Message-----
> From: chenxiang (M)
> Sent: Thursday, March 18, 2021 10:30 PM
> To: h...@lst.de; m.szyprow...@samsung.com; robin.mur...@arm.com; Song Bao Hua
> (Barry Song) <song.bao....@hisilicon.com>
> Cc: iommu@lists.linux-foundation.org; linux...@openeuler.org;
> linux-kselft...@vger.kernel.org; chenxiang (M) <chenxian...@hisilicon.com>
> Subject: [PATCH] dma-mapping: benchmark: Add support for multi-pages map/unmap
>
> From: Xiang Chen <chenxian...@hisilicon.com>
>
> 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 <chenxian...@hisilicon.com>
> ---
Acked-by: Barry Song <song.bao....@hisilicon.com>
> kernel/dma/map_benchmark.c | 21 ++++++++++++++-------
> tools/testing/selftests/dma/dma_map_benchmark.c | 20 ++++++++++++++++----
> 2 files changed, 30 insertions(+), 11 deletions(-)
>
> diff --git a/kernel/dma/map_benchmark.c b/kernel/dma/map_benchmark.c
> index e0e64f8..a5c1b01 100644
> --- a/kernel/dma/map_benchmark.c
> +++ b/kernel/dma/map_benchmark.c
> @@ -38,7 +38,8 @@ struct map_benchmark {
> __u32 dma_bits; /* DMA addressing capability */
> __u32 dma_dir; /* DMA data direction */
> __u32 dma_trans_ns; /* time for DMA transmission in ns */
> - __u8 expansion[80]; /* For future use */
> + __u32 granule; /* how many PAGE_SIZE will do map/unmap once a time */
> + __u8 expansion[76]; /* For future use */
> };
>
> struct map_benchmark_data {
> @@ -58,9 +59,11 @@ static int map_benchmark_thread(void *data)
> void *buf;
> dma_addr_t dma_addr;
> struct map_benchmark_data *map = data;
> + int npages = map->bparam.granule;
> + u64 size = npages * PAGE_SIZE;
> int ret = 0;
>
> - buf = (void *)__get_free_page(GFP_KERNEL);
> + buf = alloc_pages_exact(size, GFP_KERNEL);
> if (!buf)
> return -ENOMEM;
>
> @@ -76,10 +79,10 @@ static int map_benchmark_thread(void *data)
> * 66 means evertything goes well! 66 is lucky.
> */
> if (map->dir != DMA_FROM_DEVICE)
> - memset(buf, 0x66, PAGE_SIZE);
> + memset(buf, 0x66, size);
>
> map_stime = ktime_get();
> - dma_addr = dma_map_single(map->dev, buf, PAGE_SIZE, map->dir);
> + dma_addr = dma_map_single(map->dev, buf, size, map->dir);
> if (unlikely(dma_mapping_error(map->dev, dma_addr))) {
> pr_err("dma_map_single failed on %s\n",
> dev_name(map->dev));
> @@ -93,7 +96,7 @@ static int map_benchmark_thread(void *data)
> ndelay(map->bparam.dma_trans_ns);
>
> unmap_stime = ktime_get();
> - dma_unmap_single(map->dev, dma_addr, PAGE_SIZE, map->dir);
> + dma_unmap_single(map->dev, dma_addr, size, map->dir);
> unmap_etime = ktime_get();
> unmap_delta = ktime_sub(unmap_etime, unmap_stime);
>
> @@ -112,7 +115,7 @@ static int map_benchmark_thread(void *data)
> }
>
> out:
> - free_page((unsigned long)buf);
> + free_pages_exact(buf, size);
> return ret;
> }
>
> @@ -203,7 +206,6 @@ static long map_benchmark_ioctl(struct file *file,
> unsigned
> int cmd,
> struct map_benchmark_data *map = file->private_data;
> void __user *argp = (void __user *)arg;
> u64 old_dma_mask;
> -
> int ret;
>
> if (copy_from_user(&map->bparam, argp, sizeof(map->bparam)))
> @@ -234,6 +236,11 @@ static long map_benchmark_ioctl(struct file *file,
> unsigned
> int cmd,
> return -EINVAL;
> }
>
> + if (map->bparam.granule < 1 || map->bparam.granule > 1024) {
> + pr_err("invalid granule size\n");
> + return -EINVAL;
> + }
> +
> switch (map->bparam.dma_dir) {
> case DMA_MAP_BIDIRECTIONAL:
> map->dir = DMA_BIDIRECTIONAL;
> diff --git a/tools/testing/selftests/dma/dma_map_benchmark.c
> b/tools/testing/selftests/dma/dma_map_benchmark.c
> index fb23ce9..6f2caa6 100644
> --- a/tools/testing/selftests/dma/dma_map_benchmark.c
> +++ b/tools/testing/selftests/dma/dma_map_benchmark.c
> @@ -40,7 +40,8 @@ struct map_benchmark {
> __u32 dma_bits; /* DMA addressing capability */
> __u32 dma_dir; /* DMA data direction */
> __u32 dma_trans_ns; /* time for DMA transmission in ns */
> - __u8 expansion[80]; /* For future use */
> + __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)
> @@ -51,11 +52,13 @@ int main(int argc, char **argv)
> 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:")) != -1) {
> + while ((opt = getopt(argc, argv, "t:s:n:b:d:x:g:")) != -1) {
> switch (opt) {
> case 't':
> threads = atoi(optarg);
> @@ -75,6 +78,9 @@ int main(int argc, char **argv)
> case 'x':
> xdelay = atoi(optarg);
> break;
> + case 'g':
> + granule = atoi(optarg);
> + break;
> default:
> return -1;
> }
> @@ -110,6 +116,11 @@ int main(int argc, char **argv)
> 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");
> @@ -123,14 +134,15 @@ int main(int argc, char **argv)
> 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\n",
> - threads, seconds, node, dir[directions]);
> + 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",
> --
> 2.8.1
Thanks
Barry
_______________________________________________
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu
