benchmarks: Add vgem mmap speed test

Primarily to check that we have the WC read/write disparity.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

1 files changed, 143 insertions, 0 deletions

diff --git a/benchmarks/vgem_mmap.c b/benchmarks/vgem_mmap.c
new file mode 100644
index 00000000..7e4e459e
--- /dev/null
+++ b/benchmarks/vgem_mmap.c
@@ -0,0 +1,143 @@
+/*
+ * Copyright ©2016 Intel Corporation
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ *
+ */
+
+#include <unistd.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <string.h>
+#include <fcntl.h>
+#include <inttypes.h>
+#include <errno.h>
+#include <sys/stat.h>
+#include <sys/ioctl.h>
+#include <sys/time.h>
+#include <time.h>
+
+#include "igt.h"
+#include "igt_vgem.h"
+
+static double elapsed(const struct timespec *start,
+		      const struct timespec *end)
+{
+	return (end->tv_sec - start->tv_sec) + 1e-9*(end->tv_nsec - start->tv_nsec);
+}
+
+int main(int argc, char **argv)
+{
+	enum dir {READ, WRITE, CLEAR, FAULT} dir = READ;
+	struct timespec start, end;
+	struct vgem_bo bo;
+	void *buf;
+	void *ptr, *src, *dst;
+	int reps = 1;
+	int loops;
+	int vgem;
+	int c;
+
+	while ((c = getopt (argc, argv, "d:r:")) != -1) {
+		switch (c) {
+		case 'd':
+			if (strcmp(optarg, "read") == 0)
+				dir = READ;
+			else if (strcmp(optarg, "write") == 0)
+				dir = WRITE;
+			else if (strcmp(optarg, "clear") == 0)
+				dir = CLEAR;
+			else if (strcmp(optarg, "fault") == 0)
+				dir = FAULT;
+			else
+				abort();
+			break;
+
+		case 'r':
+			reps = atoi(optarg);
+			if (reps < 1)
+				reps = 1;
+			break;
+
+		default:
+			break;
+		}
+	}
+
+	vgem = drm_open_driver(DRIVER_VGEM);
+
+	bo.width = 2024;
+	bo.height = 2024;
+	bo.bpp = 4;
+	vgem_create(vgem, &bo);
+	ptr = vgem_mmap(vgem, &bo, PROT_WRITE);
+	buf = malloc(bo.size);
+
+	if (dir == READ) {
+		src = ptr;
+		dst = buf;
+	} else {
+		src = buf;
+		dst = ptr;
+	}
+
+	clock_gettime(CLOCK_MONOTONIC, &start);
+	switch (dir) {
+	case CLEAR:
+	case FAULT:
+		memset(dst, 0, bo.size);
+		break;
+	default:
+		memcpy(dst, src, bo.size);
+		break;
+	}
+	clock_gettime(CLOCK_MONOTONIC, &end);
+
+	loops = 2 / elapsed(&start, &end);
+	while (reps--) {
+		clock_gettime(CLOCK_MONOTONIC, &start);
+		for (c = 0; c < loops; c++) {
+			int page;
+
+			switch (dir) {
+			case CLEAR:
+				memset(dst, 0, bo.size);
+				break;
+			case FAULT:
+				munmap(ptr, bo.size);
+				ptr = vgem_mmap(vgem, &bo, PROT_WRITE);
+				for (page = 0; page < bo.size; page += 4096) {
+					uint32_t *x = (uint32_t *)ptr + page/4;
+					__asm__ __volatile__("": : :"memory");
+					page += *x; /* should be zero! */
+				}
+				break;
+			default:
+				memcpy(dst, src, bo.size);
+				break;
+			}
+		}
+		clock_gettime(CLOCK_MONOTONIC, &end);
+		printf("%7.3f\n", bo.size / elapsed(&start, &end) * loops / (1024*1024));
+	}
+
+	return 0;
+}