Merge tag 'rtc-6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux
[linux-block.git] / drivers / gpu / drm / xe / xe_exec.c
CommitLineData
dd08ebf6
MB
1// SPDX-License-Identifier: MIT
2/*
3 * Copyright © 2022 Intel Corporation
4 */
5
ea9f879d
LDM
6#include "xe_exec.h"
7
dd08ebf6 8#include <drm/drm_device.h>
d490ecf5 9#include <drm/drm_exec.h>
dd08ebf6
MB
10#include <drm/drm_file.h>
11#include <drm/xe_drm.h>
34f89ac8 12#include <linux/delay.h>
dd08ebf6
MB
13
14#include "xe_bo.h"
15#include "xe_device.h"
c22a4ed0 16#include "xe_exec_queue.h"
dd08ebf6 17#include "xe_macros.h"
8ae8a2e8 18#include "xe_ring_ops_types.h"
dd08ebf6
MB
19#include "xe_sched_job.h"
20#include "xe_sync.h"
21#include "xe_vm.h"
22
23/**
24 * DOC: Execbuf (User GPU command submission)
25 *
26 * Execs have historically been rather complicated in DRM drivers (at least in
27 * the i915) because a few things:
28 *
29 * - Passing in a list BO which are read / written to creating implicit syncs
30 * - Binding at exec time
31 * - Flow controlling the ring at exec time
32 *
33 * In XE we avoid all of this complication by not allowing a BO list to be
34 * passed into an exec, using the dma-buf implicit sync uAPI, have binds as
35 * seperate operations, and using the DRM scheduler to flow control the ring.
36 * Let's deep dive on each of these.
37 *
38 * We can get away from a BO list by forcing the user to use in / out fences on
39 * every exec rather than the kernel tracking dependencies of BO (e.g. if the
40 * user knows an exec writes to a BO and reads from the BO in the next exec, it
41 * is the user's responsibility to pass in / out fence between the two execs).
42 *
43 * Implicit dependencies for external BOs are handled by using the dma-buf
44 * implicit dependency uAPI (TODO: add link). To make this works each exec must
45 * install the job's fence into the DMA_RESV_USAGE_WRITE slot of every external
46 * BO mapped in the VM.
47 *
48 * We do not allow a user to trigger a bind at exec time rather we have a VM
49 * bind IOCTL which uses the same in / out fence interface as exec. In that
50 * sense, a VM bind is basically the same operation as an exec from the user
51 * perspective. e.g. If an exec depends on a VM bind use the in / out fence
52 * interface (struct drm_xe_sync) to synchronize like syncing between two
53 * dependent execs.
54 *
55 * Although a user cannot trigger a bind, we still have to rebind userptrs in
56 * the VM that have been invalidated since the last exec, likewise we also have
57 * to rebind BOs that have been evicted by the kernel. We schedule these rebinds
58 * behind any pending kernel operations on any external BOs in VM or any BOs
59 * private to the VM. This is accomplished by the rebinds waiting on BOs
60 * DMA_RESV_USAGE_KERNEL slot (kernel ops) and kernel ops waiting on all BOs
61 * slots (inflight execs are in the DMA_RESV_USAGE_BOOKING for private BOs and
62 * in DMA_RESV_USAGE_WRITE for external BOs).
63 *
64 * Rebinds / dma-resv usage applies to non-compute mode VMs only as for compute
65 * mode VMs we use preempt fences and a rebind worker (TODO: add link).
66 *
67 * There is no need to flow control the ring in the exec as we write the ring at
68 * submission time and set the DRM scheduler max job limit SIZE_OF_RING /
69 * MAX_JOB_SIZE. The DRM scheduler will then hold all jobs until space in the
70 * ring is available.
71 *
72 * All of this results in a rather simple exec implementation.
73 *
74 * Flow
75 * ~~~~
76 *
77 * .. code-block::
78 *
79 * Parse input arguments
80 * Wait for any async VM bind passed as in-fences to start
81 * <----------------------------------------------------------------------|
82 * Lock global VM lock in read mode |
83 * Pin userptrs (also finds userptr invalidated since last exec) |
84 * Lock exec (VM dma-resv lock, external BOs dma-resv locks) |
85 * Validate BOs that have been evicted |
86 * Create job |
87 * Rebind invalidated userptrs + evicted BOs (non-compute-mode) |
88 * Add rebind fence dependency to job |
89 * Add job VM dma-resv bookkeeping slot (non-compute mode) |
90 * Add job to external BOs dma-resv write slots (non-compute mode) |
91 * Check if any userptrs invalidated since pin ------ Drop locks ---------|
92 * Install in / out fences for job
93 * Submit job
94 * Unlock all
95 */
96
24f947d5 97static int xe_exec_fn(struct drm_gpuvm_exec *vm_exec)
dd08ebf6 98{
29f424eb
MA
99 struct xe_vm *vm = container_of(vm_exec->vm, struct xe_vm, gpuvm);
100 struct drm_gem_object *obj;
101 unsigned long index;
102 int num_fences;
103 int ret;
104
105 ret = drm_gpuvm_validate(vm_exec->vm, &vm_exec->exec);
106 if (ret)
107 return ret;
108
109 /*
f4e8ab46
MA
110 * 1 fence slot for the final submit, and 1 more for every per-tile for
111 * GPU bind and 1 extra for CPU bind. Note that there are potentially
112 * many vma per object/dma-resv, however the fence slot will just be
113 * re-used, since they are largely the same timeline and the seqno
114 * should be in order. In the case of CPU bind there is dummy fence used
115 * for all CPU binds, so no need to have a per-tile slot for that.
29f424eb 116 */
f4e8ab46 117 num_fences = 1 + 1 + vm->xe->info.tile_count;
29f424eb
MA
118
119 /*
120 * We don't know upfront exactly how many fence slots we will need at
121 * the start of the exec, since the TTM bo_validate above can consume
122 * numerous fence slots. Also due to how the dma_resv_reserve_fences()
123 * works it only ensures that at least that many fence slots are
124 * available i.e if there are already 10 slots available and we reserve
125 * two more, it can just noop without reserving anything. With this it
126 * is quite possible that TTM steals some of the fence slots and then
127 * when it comes time to do the vma binding and final exec stage we are
128 * lacking enough fence slots, leading to some nasty BUG_ON() when
129 * adding the fences. Hence just add our own fences here, after the
130 * validate stage.
131 */
132 drm_exec_for_each_locked_object(&vm_exec->exec, index, obj) {
133 ret = dma_resv_reserve_fences(obj->resv, num_fences);
134 if (ret)
135 return ret;
136 }
137
138 return 0;
dd08ebf6
MB
139}
140
dd08ebf6
MB
141int xe_exec_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
142{
143 struct xe_device *xe = to_xe_device(dev);
144 struct xe_file *xef = to_xe_file(file);
145 struct drm_xe_exec *args = data;
146 struct drm_xe_sync __user *syncs_user = u64_to_user_ptr(args->syncs);
147 u64 __user *addresses_user = u64_to_user_ptr(args->address);
9b9529ce 148 struct xe_exec_queue *q;
dd08ebf6
MB
149 struct xe_sync_entry *syncs = NULL;
150 u64 addresses[XE_HW_ENGINE_MAX_INSTANCE];
24f947d5
TH
151 struct drm_gpuvm_exec vm_exec = {.extra.fn = xe_exec_fn};
152 struct drm_exec *exec = &vm_exec.exec;
d1df9bfb 153 u32 i, num_syncs = 0, num_ufence = 0;
dd08ebf6
MB
154 struct xe_sched_job *job;
155 struct dma_fence *rebind_fence;
156 struct xe_vm *vm;
97d0047c 157 bool write_locked, skip_retry = false;
d490ecf5 158 ktime_t end = 0;
dd08ebf6
MB
159 int err = 0;
160
b8c1ba83
FD
161 if (XE_IOCTL_DBG(xe, args->extensions) ||
162 XE_IOCTL_DBG(xe, args->pad[0] || args->pad[1] || args->pad[2]) ||
163 XE_IOCTL_DBG(xe, args->reserved[0] || args->reserved[1]))
dd08ebf6
MB
164 return -EINVAL;
165
9b9529ce
FD
166 q = xe_exec_queue_lookup(xef, args->exec_queue_id);
167 if (XE_IOCTL_DBG(xe, !q))
dd08ebf6
MB
168 return -ENOENT;
169
9b9529ce 170 if (XE_IOCTL_DBG(xe, q->flags & EXEC_QUEUE_FLAG_VM))
dd08ebf6
MB
171 return -EINVAL;
172
eb9702ad
MB
173 if (XE_IOCTL_DBG(xe, args->num_batch_buffer &&
174 q->width != args->num_batch_buffer))
dd08ebf6
MB
175 return -EINVAL;
176
9b9529ce 177 if (XE_IOCTL_DBG(xe, q->flags & EXEC_QUEUE_FLAG_BANNED)) {
dd08ebf6 178 err = -ECANCELED;
9b9529ce 179 goto err_exec_queue;
dd08ebf6
MB
180 }
181
182 if (args->num_syncs) {
183 syncs = kcalloc(args->num_syncs, sizeof(*syncs), GFP_KERNEL);
184 if (!syncs) {
185 err = -ENOMEM;
9b9529ce 186 goto err_exec_queue;
dd08ebf6
MB
187 }
188 }
189
9b9529ce 190 vm = q->vm;
dd08ebf6
MB
191
192 for (i = 0; i < args->num_syncs; i++) {
193 err = xe_sync_entry_parse(xe, xef, &syncs[num_syncs++],
53bf60f6
MB
194 &syncs_user[i], SYNC_PARSE_FLAG_EXEC |
195 (xe_vm_in_lr_mode(vm) ?
196 SYNC_PARSE_FLAG_LR_MODE : 0));
dd08ebf6
MB
197 if (err)
198 goto err_syncs;
d1df9bfb
MB
199
200 if (xe_sync_is_ufence(&syncs[i]))
201 num_ufence++;
202 }
203
204 if (XE_IOCTL_DBG(xe, num_ufence > 1)) {
205 err = -EINVAL;
206 goto err_syncs;
dd08ebf6
MB
207 }
208
9b9529ce 209 if (xe_exec_queue_is_parallel(q)) {
dd08ebf6 210 err = __copy_from_user(addresses, addresses_user, sizeof(u64) *
9b9529ce 211 q->width);
dd08ebf6
MB
212 if (err) {
213 err = -EFAULT;
214 goto err_syncs;
215 }
216 }
217
dd08ebf6 218retry:
fdb6a053 219 if (!xe_vm_in_lr_mode(vm) && xe_vm_userptr_check_repin(vm)) {
dd08ebf6
MB
220 err = down_write_killable(&vm->lock);
221 write_locked = true;
222 } else {
223 /* We don't allow execs while the VM is in error state */
224 err = down_read_interruptible(&vm->lock);
225 write_locked = false;
226 }
227 if (err)
228 goto err_syncs;
229
dd08ebf6
MB
230 if (write_locked) {
231 err = xe_vm_userptr_pin(vm);
232 downgrade_write(&vm->lock);
233 write_locked = false;
234 if (err)
235 goto err_unlock_list;
236 }
237
24f947d5 238 vm_exec.vm = &vm->gpuvm;
24f947d5
TH
239 vm_exec.flags = DRM_EXEC_INTERRUPTIBLE_WAIT;
240 if (xe_vm_in_lr_mode(vm)) {
d2197029 241 drm_exec_init(exec, vm_exec.flags, 0);
24f947d5
TH
242 } else {
243 err = drm_gpuvm_exec_lock(&vm_exec);
244 if (err) {
245 if (xe_vm_validate_should_retry(exec, err, &end))
246 err = -EAGAIN;
d490ecf5
TH
247 goto err_unlock_list;
248 }
d490ecf5 249 }
dd08ebf6 250
9b9529ce 251 if (xe_vm_is_closed_or_banned(q->vm)) {
9d858b69
MB
252 drm_warn(&xe->drm, "Trying to schedule after vm is closed or banned\n");
253 err = -ECANCELED;
d490ecf5 254 goto err_exec;
dd08ebf6
MB
255 }
256
eb9702ad
MB
257 if (!args->num_batch_buffer) {
258 if (!xe_vm_in_lr_mode(vm)) {
259 struct dma_fence *fence;
260
261 fence = xe_sync_in_fence_get(syncs, num_syncs, q, vm);
262 if (IS_ERR(fence)) {
263 err = PTR_ERR(fence);
264 goto err_exec;
265 }
266 for (i = 0; i < num_syncs; i++)
267 xe_sync_entry_signal(&syncs[i], NULL, fence);
268 xe_exec_queue_last_fence_set(q, vm, fence);
269 dma_fence_put(fence);
270 }
271
272 goto err_exec;
273 }
274
9b9529ce 275 if (xe_exec_queue_is_lr(q) && xe_exec_queue_ring_full(q)) {
97d0047c
MB
276 err = -EWOULDBLOCK; /* Aliased to -EAGAIN */
277 skip_retry = true;
d490ecf5 278 goto err_exec;
8ae8a2e8
MB
279 }
280
9b9529ce 281 job = xe_sched_job_create(q, xe_exec_queue_is_parallel(q) ?
dd08ebf6
MB
282 addresses : &args->address);
283 if (IS_ERR(job)) {
284 err = PTR_ERR(job);
d490ecf5 285 goto err_exec;
dd08ebf6
MB
286 }
287
288 /*
289 * Rebind any invalidated userptr or evicted BOs in the VM, non-compute
290 * VM mode only.
291 */
292 rebind_fence = xe_vm_rebind(vm, false);
293 if (IS_ERR(rebind_fence)) {
294 err = PTR_ERR(rebind_fence);
295 goto err_put_job;
296 }
297
298 /*
299 * We store the rebind_fence in the VM so subsequent execs don't get
300 * scheduled before the rebinds of userptrs / evicted BOs is complete.
301 */
302 if (rebind_fence) {
303 dma_fence_put(vm->rebind_fence);
304 vm->rebind_fence = rebind_fence;
305 }
306 if (vm->rebind_fence) {
307 if (test_bit(DMA_FENCE_FLAG_SIGNALED_BIT,
308 &vm->rebind_fence->flags)) {
309 dma_fence_put(vm->rebind_fence);
310 vm->rebind_fence = NULL;
311 } else {
312 dma_fence_get(vm->rebind_fence);
313 err = drm_sched_job_add_dependency(&job->drm,
314 vm->rebind_fence);
315 if (err)
316 goto err_put_job;
317 }
318 }
319
320 /* Wait behind munmap style rebinds */
fdb6a053 321 if (!xe_vm_in_lr_mode(vm)) {
dd08ebf6 322 err = drm_sched_job_add_resv_dependencies(&job->drm,
b06d47be 323 xe_vm_resv(vm),
dd08ebf6
MB
324 DMA_RESV_USAGE_KERNEL);
325 if (err)
326 goto err_put_job;
327 }
328
329 for (i = 0; i < num_syncs && !err; i++)
330 err = xe_sync_entry_add_deps(&syncs[i], job);
331 if (err)
332 goto err_put_job;
333
fdb6a053 334 if (!xe_vm_in_lr_mode(vm)) {
eb9702ad
MB
335 err = xe_sched_job_last_fence_add_dep(job, vm);
336 if (err)
337 goto err_put_job;
338
dd08ebf6
MB
339 err = down_read_interruptible(&vm->userptr.notifier_lock);
340 if (err)
341 goto err_put_job;
342
343 err = __xe_vm_userptr_needs_repin(vm);
344 if (err)
345 goto err_repin;
346 }
347
348 /*
349 * Point of no return, if we error after this point just set an error on
350 * the job and let the DRM scheduler / backend clean up the job.
351 */
352 xe_sched_job_arm(job);
24f947d5
TH
353 if (!xe_vm_in_lr_mode(vm))
354 drm_gpuvm_resv_add_fence(&vm->gpuvm, exec, &job->drm.s_fence->finished,
355 DMA_RESV_USAGE_BOOKKEEP, DMA_RESV_USAGE_WRITE);
dd08ebf6
MB
356
357 for (i = 0; i < num_syncs; i++)
358 xe_sync_entry_signal(&syncs[i], job,
359 &job->drm.s_fence->finished);
360
9b9529ce
FD
361 if (xe_exec_queue_is_lr(q))
362 q->ring_ops->emit_job(job);
eb9702ad
MB
363 if (!xe_vm_in_lr_mode(vm))
364 xe_exec_queue_last_fence_set(q, vm, &job->drm.s_fence->finished);
dd08ebf6 365 xe_sched_job_push(job);
8e41443e 366 xe_vm_reactivate_rebind(vm);
dd08ebf6 367
fdb6a053 368 if (!err && !xe_vm_in_lr_mode(vm)) {
7ba4c5f0
MB
369 spin_lock(&xe->ttm.lru_lock);
370 ttm_lru_bulk_move_tail(&vm->lru_bulk_move);
371 spin_unlock(&xe->ttm.lru_lock);
372 }
373
dd08ebf6 374err_repin:
fdb6a053 375 if (!xe_vm_in_lr_mode(vm))
dd08ebf6
MB
376 up_read(&vm->userptr.notifier_lock);
377err_put_job:
378 if (err)
379 xe_sched_job_put(job);
d490ecf5 380err_exec:
24f947d5 381 drm_exec_fini(exec);
dd08ebf6
MB
382err_unlock_list:
383 if (write_locked)
384 up_write(&vm->lock);
385 else
386 up_read(&vm->lock);
97d0047c 387 if (err == -EAGAIN && !skip_retry)
dd08ebf6
MB
388 goto retry;
389err_syncs:
390 for (i = 0; i < num_syncs; i++)
391 xe_sync_entry_cleanup(&syncs[i]);
392 kfree(syncs);
9b9529ce
FD
393err_exec_queue:
394 xe_exec_queue_put(q);
dd08ebf6
MB
395
396 return err;
397}