xref: /linux/drivers/gpu/drm/tests/drm_mm_test.c (revision f6e8dc9edf963dbc99085e54f6ced6da9daa6100)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Test cases for the drm_mm range manager
4  *
5  * Copyright (c) 2022 Arthur Grillo <arthur.grillo@usp.br>
6  */
7 
8 #include <kunit/test.h>
9 
10 #include <linux/prime_numbers.h>
11 #include <linux/slab.h>
12 #include <linux/random.h>
13 #include <linux/vmalloc.h>
14 #include <linux/ktime.h>
15 
16 #include <drm/drm_mm.h>
17 #include <drm/drm_print.h>
18 
19 #include "../lib/drm_random.h"
20 
21 enum {
22 	BEST,
23 	BOTTOMUP,
24 	TOPDOWN,
25 	EVICT,
26 };
27 
28 static const struct insert_mode {
29 	const char *name;
30 	enum drm_mm_insert_mode mode;
31 } insert_modes[] = {
32 	[BEST] = { "best", DRM_MM_INSERT_BEST },
33 	[BOTTOMUP] = { "bottom-up", DRM_MM_INSERT_LOW },
34 	[TOPDOWN] = { "top-down", DRM_MM_INSERT_HIGH },
35 	[EVICT] = { "evict", DRM_MM_INSERT_EVICT },
36 	{}
37 };
38 
39 static bool assert_no_holes(struct kunit *test, const struct drm_mm *mm)
40 {
41 	struct drm_mm_node *hole;
42 	u64 hole_start, __always_unused hole_end;
43 	unsigned long count;
44 
45 	count = 0;
46 	drm_mm_for_each_hole(hole, mm, hole_start, hole_end)
47 		count++;
48 	if (count) {
49 		KUNIT_FAIL(test,
50 			   "Expected to find no holes (after reserve), found %lu instead\n", count);
51 		return false;
52 	}
53 
54 	drm_mm_for_each_node(hole, mm) {
55 		if (drm_mm_hole_follows(hole)) {
56 			KUNIT_FAIL(test, "Hole follows node, expected none!\n");
57 			return false;
58 		}
59 	}
60 
61 	return true;
62 }
63 
64 static bool assert_one_hole(struct kunit *test, const struct drm_mm *mm, u64 start, u64 end)
65 {
66 	struct drm_mm_node *hole;
67 	u64 hole_start, hole_end;
68 	unsigned long count;
69 	bool ok = true;
70 
71 	if (end <= start)
72 		return true;
73 
74 	count = 0;
75 	drm_mm_for_each_hole(hole, mm, hole_start, hole_end) {
76 		if (start != hole_start || end != hole_end) {
77 			if (ok)
78 				KUNIT_FAIL(test,
79 					   "empty mm has incorrect hole, found (%llx, %llx), expect (%llx, %llx)\n",
80 					   hole_start, hole_end, start, end);
81 			ok = false;
82 		}
83 		count++;
84 	}
85 	if (count != 1) {
86 		KUNIT_FAIL(test, "Expected to find one hole, found %lu instead\n", count);
87 		ok = false;
88 	}
89 
90 	return ok;
91 }
92 
93 static u64 misalignment(struct drm_mm_node *node, u64 alignment)
94 {
95 	u64 rem;
96 
97 	if (!alignment)
98 		return 0;
99 
100 	div64_u64_rem(node->start, alignment, &rem);
101 	return rem;
102 }
103 
104 static bool assert_node(struct kunit *test, struct drm_mm_node *node, struct drm_mm *mm,
105 			u64 size, u64 alignment, unsigned long color)
106 {
107 	bool ok = true;
108 
109 	if (!drm_mm_node_allocated(node) || node->mm != mm) {
110 		KUNIT_FAIL(test, "node not allocated\n");
111 		ok = false;
112 	}
113 
114 	if (node->size != size) {
115 		KUNIT_FAIL(test, "node has wrong size, found %llu, expected %llu\n",
116 			   node->size, size);
117 		ok = false;
118 	}
119 
120 	if (misalignment(node, alignment)) {
121 		KUNIT_FAIL(test,
122 			   "node is misaligned, start %llx rem %llu, expected alignment %llu\n",
123 			   node->start, misalignment(node, alignment), alignment);
124 		ok = false;
125 	}
126 
127 	if (node->color != color) {
128 		KUNIT_FAIL(test, "node has wrong color, found %lu, expected %lu\n",
129 			   node->color, color);
130 		ok = false;
131 	}
132 
133 	return ok;
134 }
135 
136 static void drm_test_mm_init(struct kunit *test)
137 {
138 	const unsigned int size = 4096;
139 	struct drm_mm mm;
140 	struct drm_mm_node tmp;
141 
142 	/* Start with some simple checks on initialising the struct drm_mm */
143 	memset(&mm, 0, sizeof(mm));
144 	KUNIT_ASSERT_FALSE_MSG(test, drm_mm_initialized(&mm),
145 			       "zeroed mm claims to be initialized\n");
146 
147 	memset(&mm, 0xff, sizeof(mm));
148 	drm_mm_init(&mm, 0, size);
149 	if (!drm_mm_initialized(&mm)) {
150 		KUNIT_FAIL(test, "mm claims not to be initialized\n");
151 		goto out;
152 	}
153 
154 	if (!drm_mm_clean(&mm)) {
155 		KUNIT_FAIL(test, "mm not empty on creation\n");
156 		goto out;
157 	}
158 
159 	/* After creation, it should all be one massive hole */
160 	if (!assert_one_hole(test, &mm, 0, size)) {
161 		KUNIT_FAIL(test, "mm not one hole on creation");
162 		goto out;
163 	}
164 
165 	memset(&tmp, 0, sizeof(tmp));
166 	tmp.start = 0;
167 	tmp.size = size;
168 	if (drm_mm_reserve_node(&mm, &tmp)) {
169 		KUNIT_FAIL(test, "failed to reserve whole drm_mm\n");
170 		goto out;
171 	}
172 
173 	/* After filling the range entirely, there should be no holes */
174 	if (!assert_no_holes(test, &mm)) {
175 		KUNIT_FAIL(test, "mm has holes when filled");
176 		goto out;
177 	}
178 
179 	/* And then after emptying it again, the massive hole should be back */
180 	drm_mm_remove_node(&tmp);
181 	if (!assert_one_hole(test, &mm, 0, size)) {
182 		KUNIT_FAIL(test, "mm does not have single hole after emptying");
183 		goto out;
184 	}
185 
186 out:
187 	drm_mm_takedown(&mm);
188 }
189 
190 static void drm_test_mm_debug(struct kunit *test)
191 {
192 	struct drm_printer p = drm_dbg_printer(NULL, DRM_UT_CORE, test->name);
193 	struct drm_mm mm;
194 	struct drm_mm_node nodes[2];
195 
196 	/* Create a small drm_mm with a couple of nodes and a few holes, and
197 	 * check that the debug iterator doesn't explode over a trivial drm_mm.
198 	 */
199 	drm_mm_init(&mm, 0, 4096);
200 
201 	memset(nodes, 0, sizeof(nodes));
202 	nodes[0].start = 512;
203 	nodes[0].size = 1024;
204 	KUNIT_ASSERT_FALSE_MSG(test, drm_mm_reserve_node(&mm, &nodes[0]),
205 			       "failed to reserve node[0] {start=%lld, size=%lld)\n",
206 			       nodes[0].start, nodes[0].size);
207 
208 	nodes[1].size = 1024;
209 	nodes[1].start = 4096 - 512 - nodes[1].size;
210 	KUNIT_ASSERT_FALSE_MSG(test, drm_mm_reserve_node(&mm, &nodes[1]),
211 			       "failed to reserve node[0] {start=%lld, size=%lld)\n",
212 			       nodes[0].start, nodes[0].size);
213 
214 	drm_mm_print(&mm, &p);
215 	KUNIT_SUCCEED(test);
216 }
217 
218 static bool expect_insert(struct kunit *test, struct drm_mm *mm,
219 			  struct drm_mm_node *node, u64 size, u64 alignment, unsigned long color,
220 			const struct insert_mode *mode)
221 {
222 	int err;
223 
224 	err = drm_mm_insert_node_generic(mm, node,
225 					 size, alignment, color,
226 					 mode->mode);
227 	if (err) {
228 		KUNIT_FAIL(test,
229 			   "insert (size=%llu, alignment=%llu, color=%lu, mode=%s) failed with err=%d\n",
230 			   size, alignment, color, mode->name, err);
231 		return false;
232 	}
233 
234 	if (!assert_node(test, node, mm, size, alignment, color)) {
235 		drm_mm_remove_node(node);
236 		return false;
237 	}
238 
239 	return true;
240 }
241 
242 static void drm_test_mm_align_pot(struct kunit *test, int max)
243 {
244 	struct drm_mm mm;
245 	struct drm_mm_node *node, *next;
246 	int bit;
247 
248 	/* Check that we can align to the full u64 address space */
249 
250 	drm_mm_init(&mm, 1, U64_MAX - 2);
251 
252 	for (bit = max - 1; bit; bit--) {
253 		u64 align, size;
254 
255 		node = kzalloc(sizeof(*node), GFP_KERNEL);
256 		if (!node) {
257 			KUNIT_FAIL(test, "failed to allocate node");
258 			goto out;
259 		}
260 
261 		align = BIT_ULL(bit);
262 		size = BIT_ULL(bit - 1) + 1;
263 		if (!expect_insert(test, &mm, node, size, align, bit, &insert_modes[0])) {
264 			KUNIT_FAIL(test, "insert failed with alignment=%llx [%d]", align, bit);
265 			goto out;
266 		}
267 
268 		cond_resched();
269 	}
270 
271 out:
272 	drm_mm_for_each_node_safe(node, next, &mm) {
273 		drm_mm_remove_node(node);
274 		kfree(node);
275 	}
276 	drm_mm_takedown(&mm);
277 }
278 
279 static void drm_test_mm_align32(struct kunit *test)
280 {
281 	drm_test_mm_align_pot(test, 32);
282 }
283 
284 static void drm_test_mm_align64(struct kunit *test)
285 {
286 	drm_test_mm_align_pot(test, 64);
287 }
288 
289 static void drm_test_mm_once(struct kunit *test, unsigned int mode)
290 {
291 	struct drm_mm mm;
292 	struct drm_mm_node rsvd_lo, rsvd_hi, node;
293 
294 	drm_mm_init(&mm, 0, 7);
295 
296 	memset(&rsvd_lo, 0, sizeof(rsvd_lo));
297 	rsvd_lo.start = 1;
298 	rsvd_lo.size = 1;
299 	if (drm_mm_reserve_node(&mm, &rsvd_lo)) {
300 		KUNIT_FAIL(test, "Could not reserve low node\n");
301 		goto err;
302 	}
303 
304 	memset(&rsvd_hi, 0, sizeof(rsvd_hi));
305 	rsvd_hi.start = 5;
306 	rsvd_hi.size = 1;
307 	if (drm_mm_reserve_node(&mm, &rsvd_hi)) {
308 		KUNIT_FAIL(test, "Could not reserve low node\n");
309 		goto err_lo;
310 	}
311 
312 	if (!drm_mm_hole_follows(&rsvd_lo) || !drm_mm_hole_follows(&rsvd_hi)) {
313 		KUNIT_FAIL(test, "Expected a hole after lo and high nodes!\n");
314 		goto err_hi;
315 	}
316 
317 	memset(&node, 0, sizeof(node));
318 	if (drm_mm_insert_node_generic(&mm, &node, 2, 0, 0, mode)) {
319 		KUNIT_FAIL(test, "Could not insert the node into the available hole!\n");
320 		goto err_hi;
321 	}
322 
323 	drm_mm_remove_node(&node);
324 err_hi:
325 	drm_mm_remove_node(&rsvd_hi);
326 err_lo:
327 	drm_mm_remove_node(&rsvd_lo);
328 err:
329 	drm_mm_takedown(&mm);
330 }
331 
332 static void drm_test_mm_lowest(struct kunit *test)
333 {
334 	drm_test_mm_once(test, DRM_MM_INSERT_LOW);
335 }
336 
337 static void drm_test_mm_highest(struct kunit *test)
338 {
339 	drm_test_mm_once(test, DRM_MM_INSERT_HIGH);
340 }
341 
342 static struct kunit_case drm_mm_tests[] = {
343 	KUNIT_CASE(drm_test_mm_init),
344 	KUNIT_CASE(drm_test_mm_debug),
345 	KUNIT_CASE(drm_test_mm_align32),
346 	KUNIT_CASE(drm_test_mm_align64),
347 	KUNIT_CASE(drm_test_mm_lowest),
348 	KUNIT_CASE(drm_test_mm_highest),
349 	{}
350 };
351 
352 static struct kunit_suite drm_mm_test_suite = {
353 	.name = "drm_mm",
354 	.test_cases = drm_mm_tests,
355 };
356 
357 kunit_test_suite(drm_mm_test_suite);
358 
359 MODULE_AUTHOR("Intel Corporation");
360 MODULE_DESCRIPTION("Test cases for the drm_mm range manager");
361 MODULE_LICENSE("GPL");
362