1 | // SPDX-License-Identifier: GPL-2.0 OR MIT |
2 | /* |
3 | * Copyright 2011 Red Hat Inc. |
4 | * Copyright 2023 Intel Corporation. |
5 | * All Rights Reserved. |
6 | * |
7 | * Permission is hereby granted, free of charge, to any person obtaining a |
8 | * copy of this software and associated documentation files (the |
9 | * "Software"), to deal in the Software without restriction, including |
10 | * without limitation the rights to use, copy, modify, merge, publish, |
11 | * distribute, sub license, and/or sell copies of the Software, and to |
12 | * permit persons to whom the Software is furnished to do so, subject to |
13 | * the following conditions: |
14 | * |
15 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
16 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
17 | * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL |
18 | * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, |
19 | * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR |
20 | * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE |
21 | * USE OR OTHER DEALINGS IN THE SOFTWARE. |
22 | * |
23 | * The above copyright notice and this permission notice (including the |
24 | * next paragraph) shall be included in all copies or substantial portions |
25 | * of the Software. |
26 | * |
27 | */ |
28 | /* Algorithm: |
29 | * |
30 | * We store the last allocated bo in "hole", we always try to allocate |
31 | * after the last allocated bo. Principle is that in a linear GPU ring |
32 | * progression was is after last is the oldest bo we allocated and thus |
33 | * the first one that should no longer be in use by the GPU. |
34 | * |
35 | * If it's not the case we skip over the bo after last to the closest |
36 | * done bo if such one exist. If none exist and we are not asked to |
37 | * block we report failure to allocate. |
38 | * |
39 | * If we are asked to block we wait on all the oldest fence of all |
40 | * rings. We just wait for any of those fence to complete. |
41 | */ |
42 | |
43 | #include <drm/drm_suballoc.h> |
44 | #include <drm/drm_print.h> |
45 | #include <linux/slab.h> |
46 | #include <linux/sched.h> |
47 | #include <linux/wait.h> |
48 | #include <linux/dma-fence.h> |
49 | |
50 | static void drm_suballoc_remove_locked(struct drm_suballoc *sa); |
51 | static void drm_suballoc_try_free(struct drm_suballoc_manager *sa_manager); |
52 | |
53 | /** |
54 | * drm_suballoc_manager_init() - Initialise the drm_suballoc_manager |
55 | * @sa_manager: pointer to the sa_manager |
56 | * @size: number of bytes we want to suballocate |
57 | * @align: alignment for each suballocated chunk |
58 | * |
59 | * Prepares the suballocation manager for suballocations. |
60 | */ |
61 | void drm_suballoc_manager_init(struct drm_suballoc_manager *sa_manager, |
62 | size_t size, size_t align) |
63 | { |
64 | unsigned int i; |
65 | |
66 | BUILD_BUG_ON(!is_power_of_2(DRM_SUBALLOC_MAX_QUEUES)); |
67 | |
68 | if (!align) |
69 | align = 1; |
70 | |
71 | /* alignment must be a power of 2 */ |
72 | if (WARN_ON_ONCE(align & (align - 1))) |
73 | align = roundup_pow_of_two(align); |
74 | |
75 | init_waitqueue_head(&sa_manager->wq); |
76 | sa_manager->size = size; |
77 | sa_manager->align = align; |
78 | sa_manager->hole = &sa_manager->olist; |
79 | INIT_LIST_HEAD(list: &sa_manager->olist); |
80 | for (i = 0; i < DRM_SUBALLOC_MAX_QUEUES; ++i) |
81 | INIT_LIST_HEAD(list: &sa_manager->flist[i]); |
82 | } |
83 | EXPORT_SYMBOL(drm_suballoc_manager_init); |
84 | |
85 | /** |
86 | * drm_suballoc_manager_fini() - Destroy the drm_suballoc_manager |
87 | * @sa_manager: pointer to the sa_manager |
88 | * |
89 | * Cleans up the suballocation manager after use. All fences added |
90 | * with drm_suballoc_free() must be signaled, or we cannot clean up |
91 | * the entire manager. |
92 | */ |
93 | void drm_suballoc_manager_fini(struct drm_suballoc_manager *sa_manager) |
94 | { |
95 | struct drm_suballoc *sa, *tmp; |
96 | |
97 | if (!sa_manager->size) |
98 | return; |
99 | |
100 | if (!list_empty(head: &sa_manager->olist)) { |
101 | sa_manager->hole = &sa_manager->olist; |
102 | drm_suballoc_try_free(sa_manager); |
103 | if (!list_empty(head: &sa_manager->olist)) |
104 | DRM_ERROR("sa_manager is not empty, clearing anyway\n" ); |
105 | } |
106 | list_for_each_entry_safe(sa, tmp, &sa_manager->olist, olist) { |
107 | drm_suballoc_remove_locked(sa); |
108 | } |
109 | |
110 | sa_manager->size = 0; |
111 | } |
112 | EXPORT_SYMBOL(drm_suballoc_manager_fini); |
113 | |
114 | static void drm_suballoc_remove_locked(struct drm_suballoc *sa) |
115 | { |
116 | struct drm_suballoc_manager *sa_manager = sa->manager; |
117 | |
118 | if (sa_manager->hole == &sa->olist) |
119 | sa_manager->hole = sa->olist.prev; |
120 | |
121 | list_del_init(entry: &sa->olist); |
122 | list_del_init(entry: &sa->flist); |
123 | dma_fence_put(fence: sa->fence); |
124 | kfree(objp: sa); |
125 | } |
126 | |
127 | static void drm_suballoc_try_free(struct drm_suballoc_manager *sa_manager) |
128 | { |
129 | struct drm_suballoc *sa, *tmp; |
130 | |
131 | if (sa_manager->hole->next == &sa_manager->olist) |
132 | return; |
133 | |
134 | sa = list_entry(sa_manager->hole->next, struct drm_suballoc, olist); |
135 | list_for_each_entry_safe_from(sa, tmp, &sa_manager->olist, olist) { |
136 | if (!sa->fence || !dma_fence_is_signaled(fence: sa->fence)) |
137 | return; |
138 | |
139 | drm_suballoc_remove_locked(sa); |
140 | } |
141 | } |
142 | |
143 | static size_t drm_suballoc_hole_soffset(struct drm_suballoc_manager *sa_manager) |
144 | { |
145 | struct list_head *hole = sa_manager->hole; |
146 | |
147 | if (hole != &sa_manager->olist) |
148 | return list_entry(hole, struct drm_suballoc, olist)->eoffset; |
149 | |
150 | return 0; |
151 | } |
152 | |
153 | static size_t drm_suballoc_hole_eoffset(struct drm_suballoc_manager *sa_manager) |
154 | { |
155 | struct list_head *hole = sa_manager->hole; |
156 | |
157 | if (hole->next != &sa_manager->olist) |
158 | return list_entry(hole->next, struct drm_suballoc, olist)->soffset; |
159 | return sa_manager->size; |
160 | } |
161 | |
162 | static bool drm_suballoc_try_alloc(struct drm_suballoc_manager *sa_manager, |
163 | struct drm_suballoc *sa, |
164 | size_t size, size_t align) |
165 | { |
166 | size_t soffset, eoffset, wasted; |
167 | |
168 | soffset = drm_suballoc_hole_soffset(sa_manager); |
169 | eoffset = drm_suballoc_hole_eoffset(sa_manager); |
170 | wasted = round_up(soffset, align) - soffset; |
171 | |
172 | if ((eoffset - soffset) >= (size + wasted)) { |
173 | soffset += wasted; |
174 | |
175 | sa->manager = sa_manager; |
176 | sa->soffset = soffset; |
177 | sa->eoffset = soffset + size; |
178 | list_add(new: &sa->olist, head: sa_manager->hole); |
179 | INIT_LIST_HEAD(list: &sa->flist); |
180 | sa_manager->hole = &sa->olist; |
181 | return true; |
182 | } |
183 | return false; |
184 | } |
185 | |
186 | static bool __drm_suballoc_event(struct drm_suballoc_manager *sa_manager, |
187 | size_t size, size_t align) |
188 | { |
189 | size_t soffset, eoffset, wasted; |
190 | unsigned int i; |
191 | |
192 | for (i = 0; i < DRM_SUBALLOC_MAX_QUEUES; ++i) |
193 | if (!list_empty(head: &sa_manager->flist[i])) |
194 | return true; |
195 | |
196 | soffset = drm_suballoc_hole_soffset(sa_manager); |
197 | eoffset = drm_suballoc_hole_eoffset(sa_manager); |
198 | wasted = round_up(soffset, align) - soffset; |
199 | |
200 | return ((eoffset - soffset) >= (size + wasted)); |
201 | } |
202 | |
203 | /** |
204 | * drm_suballoc_event() - Check if we can stop waiting |
205 | * @sa_manager: pointer to the sa_manager |
206 | * @size: number of bytes we want to allocate |
207 | * @align: alignment we need to match |
208 | * |
209 | * Return: true if either there is a fence we can wait for or |
210 | * enough free memory to satisfy the allocation directly. |
211 | * false otherwise. |
212 | */ |
213 | static bool drm_suballoc_event(struct drm_suballoc_manager *sa_manager, |
214 | size_t size, size_t align) |
215 | { |
216 | bool ret; |
217 | |
218 | spin_lock(lock: &sa_manager->wq.lock); |
219 | ret = __drm_suballoc_event(sa_manager, size, align); |
220 | spin_unlock(lock: &sa_manager->wq.lock); |
221 | return ret; |
222 | } |
223 | |
224 | static bool drm_suballoc_next_hole(struct drm_suballoc_manager *sa_manager, |
225 | struct dma_fence **fences, |
226 | unsigned int *tries) |
227 | { |
228 | struct drm_suballoc *best_bo = NULL; |
229 | unsigned int i, best_idx; |
230 | size_t soffset, best, tmp; |
231 | |
232 | /* if hole points to the end of the buffer */ |
233 | if (sa_manager->hole->next == &sa_manager->olist) { |
234 | /* try again with its beginning */ |
235 | sa_manager->hole = &sa_manager->olist; |
236 | return true; |
237 | } |
238 | |
239 | soffset = drm_suballoc_hole_soffset(sa_manager); |
240 | /* to handle wrap around we add sa_manager->size */ |
241 | best = sa_manager->size * 2; |
242 | /* go over all fence list and try to find the closest sa |
243 | * of the current last |
244 | */ |
245 | for (i = 0; i < DRM_SUBALLOC_MAX_QUEUES; ++i) { |
246 | struct drm_suballoc *sa; |
247 | |
248 | fences[i] = NULL; |
249 | |
250 | if (list_empty(head: &sa_manager->flist[i])) |
251 | continue; |
252 | |
253 | sa = list_first_entry(&sa_manager->flist[i], |
254 | struct drm_suballoc, flist); |
255 | |
256 | if (!dma_fence_is_signaled(fence: sa->fence)) { |
257 | fences[i] = sa->fence; |
258 | continue; |
259 | } |
260 | |
261 | /* limit the number of tries each freelist gets */ |
262 | if (tries[i] > 2) |
263 | continue; |
264 | |
265 | tmp = sa->soffset; |
266 | if (tmp < soffset) { |
267 | /* wrap around, pretend it's after */ |
268 | tmp += sa_manager->size; |
269 | } |
270 | tmp -= soffset; |
271 | if (tmp < best) { |
272 | /* this sa bo is the closest one */ |
273 | best = tmp; |
274 | best_idx = i; |
275 | best_bo = sa; |
276 | } |
277 | } |
278 | |
279 | if (best_bo) { |
280 | ++tries[best_idx]; |
281 | sa_manager->hole = best_bo->olist.prev; |
282 | |
283 | /* |
284 | * We know that this one is signaled, |
285 | * so it's safe to remove it. |
286 | */ |
287 | drm_suballoc_remove_locked(sa: best_bo); |
288 | return true; |
289 | } |
290 | return false; |
291 | } |
292 | |
293 | /** |
294 | * drm_suballoc_new() - Make a suballocation. |
295 | * @sa_manager: pointer to the sa_manager |
296 | * @size: number of bytes we want to suballocate. |
297 | * @gfp: gfp flags used for memory allocation. Typically GFP_KERNEL but |
298 | * the argument is provided for suballocations from reclaim context or |
299 | * where the caller wants to avoid pipelining rather than wait for |
300 | * reclaim. |
301 | * @intr: Whether to perform waits interruptible. This should typically |
302 | * always be true, unless the caller needs to propagate a |
303 | * non-interruptible context from above layers. |
304 | * @align: Alignment. Must not exceed the default manager alignment. |
305 | * If @align is zero, then the manager alignment is used. |
306 | * |
307 | * Try to make a suballocation of size @size, which will be rounded |
308 | * up to the alignment specified in specified in drm_suballoc_manager_init(). |
309 | * |
310 | * Return: a new suballocated bo, or an ERR_PTR. |
311 | */ |
312 | struct drm_suballoc * |
313 | drm_suballoc_new(struct drm_suballoc_manager *sa_manager, size_t size, |
314 | gfp_t gfp, bool intr, size_t align) |
315 | { |
316 | struct dma_fence *fences[DRM_SUBALLOC_MAX_QUEUES]; |
317 | unsigned int tries[DRM_SUBALLOC_MAX_QUEUES]; |
318 | unsigned int count; |
319 | int i, r; |
320 | struct drm_suballoc *sa; |
321 | |
322 | if (WARN_ON_ONCE(align > sa_manager->align)) |
323 | return ERR_PTR(error: -EINVAL); |
324 | if (WARN_ON_ONCE(size > sa_manager->size || !size)) |
325 | return ERR_PTR(error: -EINVAL); |
326 | |
327 | if (!align) |
328 | align = sa_manager->align; |
329 | |
330 | sa = kmalloc(size: sizeof(*sa), flags: gfp); |
331 | if (!sa) |
332 | return ERR_PTR(error: -ENOMEM); |
333 | sa->manager = sa_manager; |
334 | sa->fence = NULL; |
335 | INIT_LIST_HEAD(list: &sa->olist); |
336 | INIT_LIST_HEAD(list: &sa->flist); |
337 | |
338 | spin_lock(lock: &sa_manager->wq.lock); |
339 | do { |
340 | for (i = 0; i < DRM_SUBALLOC_MAX_QUEUES; ++i) |
341 | tries[i] = 0; |
342 | |
343 | do { |
344 | drm_suballoc_try_free(sa_manager); |
345 | |
346 | if (drm_suballoc_try_alloc(sa_manager, sa, |
347 | size, align)) { |
348 | spin_unlock(lock: &sa_manager->wq.lock); |
349 | return sa; |
350 | } |
351 | |
352 | /* see if we can skip over some allocations */ |
353 | } while (drm_suballoc_next_hole(sa_manager, fences, tries)); |
354 | |
355 | for (i = 0, count = 0; i < DRM_SUBALLOC_MAX_QUEUES; ++i) |
356 | if (fences[i]) |
357 | fences[count++] = dma_fence_get(fence: fences[i]); |
358 | |
359 | if (count) { |
360 | long t; |
361 | |
362 | spin_unlock(lock: &sa_manager->wq.lock); |
363 | t = dma_fence_wait_any_timeout(fences, count, intr, |
364 | MAX_SCHEDULE_TIMEOUT, |
365 | NULL); |
366 | for (i = 0; i < count; ++i) |
367 | dma_fence_put(fence: fences[i]); |
368 | |
369 | r = (t > 0) ? 0 : t; |
370 | spin_lock(lock: &sa_manager->wq.lock); |
371 | } else if (intr) { |
372 | /* if we have nothing to wait for block */ |
373 | r = wait_event_interruptible_locked |
374 | (sa_manager->wq, |
375 | __drm_suballoc_event(sa_manager, size, align)); |
376 | } else { |
377 | spin_unlock(lock: &sa_manager->wq.lock); |
378 | wait_event(sa_manager->wq, |
379 | drm_suballoc_event(sa_manager, size, align)); |
380 | r = 0; |
381 | spin_lock(lock: &sa_manager->wq.lock); |
382 | } |
383 | } while (!r); |
384 | |
385 | spin_unlock(lock: &sa_manager->wq.lock); |
386 | kfree(objp: sa); |
387 | return ERR_PTR(error: r); |
388 | } |
389 | EXPORT_SYMBOL(drm_suballoc_new); |
390 | |
391 | /** |
392 | * drm_suballoc_free - Free a suballocation |
393 | * @suballoc: pointer to the suballocation |
394 | * @fence: fence that signals when suballocation is idle |
395 | * |
396 | * Free the suballocation. The suballocation can be re-used after @fence signals. |
397 | */ |
398 | void drm_suballoc_free(struct drm_suballoc *suballoc, |
399 | struct dma_fence *fence) |
400 | { |
401 | struct drm_suballoc_manager *sa_manager; |
402 | |
403 | if (!suballoc) |
404 | return; |
405 | |
406 | sa_manager = suballoc->manager; |
407 | |
408 | spin_lock(lock: &sa_manager->wq.lock); |
409 | if (fence && !dma_fence_is_signaled(fence)) { |
410 | u32 idx; |
411 | |
412 | suballoc->fence = dma_fence_get(fence); |
413 | idx = fence->context & (DRM_SUBALLOC_MAX_QUEUES - 1); |
414 | list_add_tail(new: &suballoc->flist, head: &sa_manager->flist[idx]); |
415 | } else { |
416 | drm_suballoc_remove_locked(sa: suballoc); |
417 | } |
418 | wake_up_all_locked(&sa_manager->wq); |
419 | spin_unlock(lock: &sa_manager->wq.lock); |
420 | } |
421 | EXPORT_SYMBOL(drm_suballoc_free); |
422 | |
423 | #ifdef CONFIG_DEBUG_FS |
424 | void drm_suballoc_dump_debug_info(struct drm_suballoc_manager *sa_manager, |
425 | struct drm_printer *p, |
426 | unsigned long long suballoc_base) |
427 | { |
428 | struct drm_suballoc *i; |
429 | |
430 | spin_lock(lock: &sa_manager->wq.lock); |
431 | list_for_each_entry(i, &sa_manager->olist, olist) { |
432 | unsigned long long soffset = i->soffset; |
433 | unsigned long long eoffset = i->eoffset; |
434 | |
435 | if (&i->olist == sa_manager->hole) |
436 | drm_puts(p, str: ">" ); |
437 | else |
438 | drm_puts(p, str: " " ); |
439 | |
440 | drm_printf(p, f: "[0x%010llx 0x%010llx] size %8lld" , |
441 | suballoc_base + soffset, suballoc_base + eoffset, |
442 | eoffset - soffset); |
443 | |
444 | if (i->fence) |
445 | drm_printf(p, f: " protected by 0x%016llx on context %llu" , |
446 | (unsigned long long)i->fence->seqno, |
447 | (unsigned long long)i->fence->context); |
448 | |
449 | drm_puts(p, str: "\n" ); |
450 | } |
451 | spin_unlock(lock: &sa_manager->wq.lock); |
452 | } |
453 | EXPORT_SYMBOL(drm_suballoc_dump_debug_info); |
454 | #endif |
455 | MODULE_AUTHOR("Multiple" ); |
456 | MODULE_DESCRIPTION("Range suballocator helper" ); |
457 | MODULE_LICENSE("Dual MIT/GPL" ); |
458 | |