tests: Add a fenced execbuffer thrash test

Exercise a nasty corner-case in the reservation logic for the fence
accounting.

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

.gitignore

@@ -37,6 +37,7 @@ tests/gem_basic
 tests/gem_exec_blt
 tests/gem_exec_nop
 tests/gem_fence_thrash
+tests/gem_fenced_exec_thrash
 tests/gem_flink
 tests/gem_gtt_speed
 tests/gem_largeobject

tests/Makefile.am

@@ -32,6 +32,7 @@ TESTS = getversion \
 	gem_bad_address \
 	gem_bad_blit \
 	gem_fence_thrash \
+	gem_fenced_exec_thrash \
 	gem_gtt_speed \
 	$(NULL)
 

tests/gem_fenced_exec_thrash.c

@@ -0,0 +1,184 @@
+/*
+ * Copyright © 2011 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.
+ *
+ * Authors:
+ *    Chris Wilson <chris@chris-wilson.co.uk>
+ *
+ */
+
+#define _GNU_SOURCE
+
+#include <stdlib.h>
+#include <sys/ioctl.h>
+#include <stdio.h>
+#include <string.h>
+#include <assert.h>
+#include <fcntl.h>
+#include <inttypes.h>
+#include <drm.h>
+#include <i915_drm.h>
+
+#include "drmtest.h"
+
+#define WIDTH 1024
+#define HEIGHT 1024
+#define OBJECT_SIZE (4*WIDTH*HEIGHT)
+
+#define BATCH_SIZE 4096
+
+#define MAX_FENCES 16
+
+#define MI_BATCH_BUFFER_END	(0xA<<23)
+
+/*
+ * We had a bug where we were falsely accounting upon reservation already
+ * fenced buffers as occupying a fence register even if they did not require
+ * one for the batch.
+ *
+ * We aim to exercise this by performing a sequence of fenced BLT
+ * with 2*num_avail_fence buffers, but alternating which half are fenced in
+ * each command.
+ */
+
+static uint32_t
+tiled_bo_create (int fd)
+{
+	struct drm_i915_gem_create create;
+	struct drm_i915_gem_set_tiling tiling;
+	int ret;
+
+	memset(&create, 0, sizeof(create));
+	create.size = OBJECT_SIZE;
+	ret = ioctl(fd, DRM_IOCTL_I915_GEM_CREATE, &create);
+	assert(ret == 0);
+
+	memset(&tiling, 0, sizeof(tiling));
+	tiling.handle = create.handle;
+	tiling.tiling_mode = I915_TILING_X;
+	tiling.stride = WIDTH*4;
+	ret = ioctl(fd, DRM_IOCTL_I915_GEM_SET_TILING, &tiling);
+	assert(ret == 0);
+
+	return create.handle;
+}
+
+static uint32_t
+batch_create (int fd)
+{
+	struct drm_i915_gem_create create;
+	struct drm_i915_gem_pwrite pwrite;
+	uint32_t buf[] = { MI_BATCH_BUFFER_END, 0 };
+	int ret;
+
+	memset(&create, 0, sizeof(create));
+	create.size = BATCH_SIZE;
+	ret = ioctl(fd, DRM_IOCTL_I915_GEM_CREATE, &create);
+	assert(ret == 0);
+
+	pwrite.handle = create.handle;
+	pwrite.offset = 0;
+	pwrite.size = sizeof(buf);
+	pwrite.data_ptr = (uintptr_t)buf;
+	ret = drmIoctl(fd, DRM_IOCTL_I915_GEM_PWRITE, &pwrite);
+	assert(ret == 0);
+
+	return create.handle;
+}
+
+static int get_num_fences(int fd)
+{
+	drm_i915_getparam_t gp;
+	int ret, val;
+
+	gp.param = I915_PARAM_NUM_FENCES_AVAIL;
+	gp.value = &val;
+	ret = drmIoctl(fd, DRM_IOCTL_I915_GETPARAM, &gp);
+	assert (ret == 0);
+
+	printf ("total %d fences\n", val);
+	assert(val > 4);
+
+	return val - 2;
+}
+
+static void fill_reloc(struct drm_i915_gem_relocation_entry *reloc, uint32_t handle)
+{
+	reloc->offset = 2 * sizeof(uint32_t);
+	reloc->target_handle = handle;
+	reloc->read_domains = I915_GEM_DOMAIN_RENDER;
+	reloc->write_domain = 0;
+}
+
+int
+main(int argc, char **argv)
+{
+	struct drm_i915_gem_execbuffer2 execbuf[2];
+	struct drm_i915_gem_exec_object2 exec[2][2*MAX_FENCES+1];
+	struct drm_i915_gem_relocation_entry reloc[2*MAX_FENCES];
+
+	int fd = drm_open_any();
+	int i, n, num_fences;
+	int loop = 1000;
+
+	memset(execbuf, 0, sizeof(execbuf));
+	memset(exec, 0, sizeof(exec));
+	memset(reloc, 0, sizeof(reloc));
+
+	num_fences = get_num_fences(fd) & ~1;
+	assert(num_fences <= MAX_FENCES);
+	for (n = 0; n < 2*num_fences; n++) {
+		uint32_t handle = tiled_bo_create(fd);
+		exec[1][2*num_fences - n-1].handle = exec[0][n].handle = handle;
+		fill_reloc(&reloc[n], handle);
+	}
+
+	for (i = 0; i < 2; i++) {
+		for (n = 0; n < num_fences; n++)
+			exec[i][n].flags = EXEC_OBJECT_NEEDS_FENCE;
+
+		exec[i][2*num_fences].handle = batch_create(fd);
+		exec[i][2*num_fences].relocs_ptr = (uintptr_t)reloc;
+		exec[i][2*num_fences].relocation_count = 2*num_fences;
+
+		execbuf[i].buffers_ptr = (uintptr_t)exec[i];
+		execbuf[i].buffer_count = 2*num_fences+1;
+		execbuf[i].batch_len = 2*sizeof(uint32_t);
+	}
+
+	do {
+		int ret;
+
+		ret = drmIoctl(fd,
+			       DRM_IOCTL_I915_GEM_EXECBUFFER2,
+			       &execbuf[0]);
+		assert(ret == 0);
+
+		ret = drmIoctl(fd,
+			       DRM_IOCTL_I915_GEM_EXECBUFFER2,
+			       &execbuf[1]);
+		assert(ret == 0);
+	} while (--loop);
+
+	close(fd);
+
+	return 0;
+}