tools/dma: move dma_map_benchmark from selftests to tools/dma

dma_map_benchmark is a standalone developer tool rather than an
automated selftest. It has no pass/fail criteria, expects manual
invocation, and is built as a normal userspace binary. Move it to
tools/dma/ and add a minimal Makefile.

Suggested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Suggested-by: Barry Song <baohua@kernel.org>
Signed-off-by: Qinxin Xia <xiaqinxin@huawei.com>
Acked-by: Barry Song <baohua@kernel.org>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/r/20251028120900.2265511-3-xiaqinxin@huawei.com

1 files changed, 127 insertions, 0 deletions

diff --git a/tools/dma/dma_map_benchmark.c b/tools/dma/dma_map_benchmark.c
new file mode 100644
index 000000000000..5474a450863c
--- /dev/null
+++ b/tools/dma/dma_map_benchmark.c
@@ -0,0 +1,127 @@
+// 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/map_benchmark.h>
+
+#define NSEC_PER_MSEC	1000000L
+
+static char *directions[] = {
+	"BIDIRECTIONAL",
+	"TO_DEVICE",
+	"FROM_DEVICE",
+};
+
+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;
+
+	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;
+}