drivers/gpu/drm/i915/gt/selftest_context.c

   1 /*
   2  * SPDX-License-Identifier: GPL-2.0
   3  *
   4  * Copyright © 2019 Intel Corporation
   5  */
   6
   7 #include "i915_selftest.h"
   8 #include "intel_engine_heartbeat.h"
   9 #include "intel_engine_pm.h"
  10 #include "intel_gt.h"
  11
  12 #include "gem/selftests/mock_context.h"
  13 #include "selftests/igt_flush_test.h"
  14 #include "selftests/mock_drm.h"
  15
  16 static int request_sync(struct i915_request *rq)
  17 {
  18         struct intel_timeline *tl = i915_request_timeline(rq);
  19         long timeout;
  20         int err = 0;
  21
  22         intel_timeline_get(tl);
  23         i915_request_get(rq);
  24
  25         /* Opencode i915_request_add() so we can keep the timeline locked. */
  26         __i915_request_commit(rq);
  27         rq->sched.attr.priority = I915_PRIORITY_BARRIER;
  28         __i915_request_queue(rq, NULL);
  29
  30         timeout = i915_request_wait(rq, 0, HZ / 10);
  31         if (timeout < 0)
  32                 err = timeout;
  33         else
  34                 i915_request_retire_upto(rq);
  35
  36         lockdep_unpin_lock(&tl->mutex, rq->cookie);
  37         mutex_unlock(&tl->mutex);
  38
  39         i915_request_put(rq);
  40         intel_timeline_put(tl);
  41
  42         return err;
  43 }
  44
  45 static int context_sync(struct intel_context *ce)
  46 {
  47         struct intel_timeline *tl = ce->timeline;
  48         int err = 0;
  49
  50         mutex_lock(&tl->mutex);
  51         do {
  52                 struct i915_request *rq;
  53                 long timeout;
  54
  55                 if (list_empty(&tl->requests))
  56                         break;
  57
  58                 rq = list_last_entry(&tl->requests, typeof(*rq), link);
  59                 i915_request_get(rq);
  60
  61                 timeout = i915_request_wait(rq, 0, HZ / 10);
  62                 if (timeout < 0)
  63                         err = timeout;
  64                 else
  65                         i915_request_retire_upto(rq);
  66
  67                 i915_request_put(rq);
  68         } while (!err);
  69         mutex_unlock(&tl->mutex);
  70
  71         /* Wait for all barriers to complete (remote CPU) before we check */
  72         i915_active_unlock_wait(&ce->active);
  73         return err;
  74 }
  75
  76 static int __live_context_size(struct intel_engine_cs *engine)
  77 {
  78         struct intel_context *ce;
  79         struct i915_request *rq;
  80         void *vaddr;
  81         int err;
  82
  83         ce = intel_context_create(engine);
  84         if (IS_ERR(ce))
  85                 return PTR_ERR(ce);
  86
  87         err = intel_context_pin(ce);
  88         if (err)
  89                 goto err;
  90
  91         vaddr = i915_gem_object_pin_map(ce->state->obj,
  92                                         i915_coherent_map_type(engine->i915));
  93         if (IS_ERR(vaddr)) {
  94                 err = PTR_ERR(vaddr);
  95                 intel_context_unpin(ce);
  96                 goto err;
  97         }
  98
  99         /*
 100          * Note that execlists also applies a redzone which it checks on
 101          * context unpin when debugging. We are using the same location
 102          * and same poison value so that our checks overlap. Despite the
 103          * redundancy, we want to keep this little selftest so that we
 104          * get coverage of any and all submission backends, and we can
 105          * always extend this test to ensure we trick the HW into a
 106          * compromising position wrt to the various sections that need
 107          * to be written into the context state.
 108          *
 109          * TLDR; this overlaps with the execlists redzone.
 110          */
 111         vaddr += engine->context_size - I915_GTT_PAGE_SIZE;
 112         memset(vaddr, POISON_INUSE, I915_GTT_PAGE_SIZE);
 113
 114         rq = intel_context_create_request(ce);
 115         intel_context_unpin(ce);
 116         if (IS_ERR(rq)) {
 117                 err = PTR_ERR(rq);
 118                 goto err_unpin;
 119         }
 120
 121         err = request_sync(rq);
 122         if (err)
 123                 goto err_unpin;
 124
 125         /* Force the context switch */
 126         rq = intel_engine_create_kernel_request(engine);
 127         if (IS_ERR(rq)) {
 128                 err = PTR_ERR(rq);
 129                 goto err_unpin;
 130         }
 131         err = request_sync(rq);
 132         if (err)
 133                 goto err_unpin;
 134
 135         if (memchr_inv(vaddr, POISON_INUSE, I915_GTT_PAGE_SIZE)) {
 136                 pr_err("%s context overwrote trailing red-zone!", engine->name);
 137                 err = -EINVAL;
 138         }
 139
 140 err_unpin:
 141         i915_gem_object_unpin_map(ce->state->obj);
 142 err:
 143         intel_context_put(ce);
 144         return err;
 145 }
 146
 147 static int live_context_size(void *arg)
 148 {
 149         struct intel_gt *gt = arg;
 150         struct intel_engine_cs *engine;
 151         enum intel_engine_id id;
 152         int err = 0;
 153
 154         /*
 155          * Check that our context sizes are correct by seeing if the
 156          * HW tries to write past the end of one.
 157          */
 158
 159         for_each_engine(engine, gt, id) {
 160                 struct file *saved;
 161
 162                 if (!engine->context_size)
 163                         continue;
 164
 165                 intel_engine_pm_get(engine);
 166
 167                 /*
 168                  * Hide the old default state -- we lie about the context size
 169                  * and get confused when the default state is smaller than
 170                  * expected. For our do nothing request, inheriting the
 171                  * active state is sufficient, we are only checking that we
 172                  * don't use more than we planned.
 173                  */
 174                 saved = fetch_and_zero(&engine->default_state);
 175
 176                 /* Overlaps with the execlists redzone */
 177                 engine->context_size += I915_GTT_PAGE_SIZE;
 178
 179                 err = __live_context_size(engine);
 180
 181                 engine->context_size -= I915_GTT_PAGE_SIZE;
 182
 183                 engine->default_state = saved;
 184
 185                 intel_engine_pm_put(engine);
 186
 187                 if (err)
 188                         break;
 189         }
 190
 191         return err;
 192 }
 193
 194 static int __live_active_context(struct intel_engine_cs *engine)
 195 {
 196         unsigned long saved_heartbeat;
 197         struct intel_context *ce;
 198         int pass;
 199         int err;
 200
 201         /*
 202          * We keep active contexts alive until after a subsequent context
 203          * switch as the final write from the context-save will be after
 204          * we retire the final request. We track when we unpin the context,
 205          * under the presumption that the final pin is from the last request,
 206          * and instead of immediately unpinning the context, we add a task
 207          * to unpin the context from the next idle-barrier.
 208          *
 209          * This test makes sure that the context is kept alive until a
 210          * subsequent idle-barrier (emitted when the engine wakeref hits 0
 211          * with no more outstanding requests).
 212          */
 213
 214         if (intel_engine_pm_is_awake(engine)) {
 215                 pr_err("%s is awake before starting %s!\n",
 216                        engine->name, __func__);
 217                 return -EINVAL;
 218         }
 219
 220         ce = intel_context_create(engine);
 221         if (IS_ERR(ce))
 222                 return PTR_ERR(ce);
 223
 224         saved_heartbeat = engine->props.heartbeat_interval_ms;
 225         engine->props.heartbeat_interval_ms = 0;
 226
 227         for (pass = 0; pass <= 2; pass++) {
 228                 struct i915_request *rq;
 229
 230                 intel_engine_pm_get(engine);
 231
 232                 rq = intel_context_create_request(ce);
 233                 if (IS_ERR(rq)) {
 234                         err = PTR_ERR(rq);
 235                         goto out_engine;
 236                 }
 237
 238                 err = request_sync(rq);
 239                 if (err)
 240                         goto out_engine;
 241
 242                 /* Context will be kept active until after an idle-barrier. */
 243                 if (i915_active_is_idle(&ce->active)) {
 244                         pr_err("context is not active; expected idle-barrier (%s pass %d)\n",
 245                                engine->name, pass);
 246                         err = -EINVAL;
 247                         goto out_engine;
 248                 }
 249
 250                 if (!intel_engine_pm_is_awake(engine)) {
 251                         pr_err("%s is asleep before idle-barrier\n",
 252                                engine->name);
 253                         err = -EINVAL;
 254                         goto out_engine;
 255                 }
 256
 257 out_engine:
 258                 intel_engine_pm_put(engine);
 259                 if (err)
 260                         goto err;
 261         }
 262
 263         /* Now make sure our idle-barriers are flushed */
 264         err = intel_engine_flush_barriers(engine);
 265         if (err)
 266                 goto err;
 267
 268         /* Wait for the barrier and in the process wait for engine to park */
 269         err = context_sync(engine->kernel_context);
 270         if (err)
 271                 goto err;
 272
 273         if (!i915_active_is_idle(&ce->active)) {
 274                 pr_err("context is still active!");
 275                 err = -EINVAL;
 276         }
 277
 278         intel_engine_pm_flush(engine);
 279
 280         if (intel_engine_pm_is_awake(engine)) {
 281                 struct drm_printer p = drm_debug_printer(__func__);
 282
 283                 intel_engine_dump(engine, &p,
 284                                   "%s is still awake:%d after idle-barriers\n",
 285                                   engine->name,
 286                                   atomic_read(&engine->wakeref.count));
 287                 GEM_TRACE_DUMP();
 288
 289                 err = -EINVAL;
 290                 goto err;
 291         }
 292
 293 err:
 294         engine->props.heartbeat_interval_ms = saved_heartbeat;
 295         intel_context_put(ce);
 296         return err;
 297 }
 298
 299 static int live_active_context(void *arg)
 300 {
 301         struct intel_gt *gt = arg;
 302         struct intel_engine_cs *engine;
 303         enum intel_engine_id id;
 304         int err = 0;
 305
 306         for_each_engine(engine, gt, id) {
 307                 err = __live_active_context(engine);
 308                 if (err)
 309                         break;
 310
 311                 err = igt_flush_test(gt->i915);
 312                 if (err)
 313                         break;
 314         }
 315
 316         return err;
 317 }
 318
 319 static int __remote_sync(struct intel_context *ce, struct intel_context *remote)
 320 {
 321         struct i915_request *rq;
 322         int err;
 323
 324         err = intel_context_pin(remote);
 325         if (err)
 326                 return err;
 327
 328         rq = intel_context_create_request(ce);
 329         if (IS_ERR(rq)) {
 330                 err = PTR_ERR(rq);
 331                 goto unpin;
 332         }
 333
 334         err = intel_context_prepare_remote_request(remote, rq);
 335         if (err) {
 336                 i915_request_add(rq);
 337                 goto unpin;
 338         }
 339
 340         err = request_sync(rq);
 341
 342 unpin:
 343         intel_context_unpin(remote);
 344         return err;
 345 }
 346
 347 static int __live_remote_context(struct intel_engine_cs *engine)
 348 {
 349         struct intel_context *local, *remote;
 350         unsigned long saved_heartbeat;
 351         int pass;
 352         int err;
 353
 354         /*
 355          * Check that our idle barriers do not interfere with normal
 356          * activity tracking. In particular, check that operating
 357          * on the context image remotely (intel_context_prepare_remote_request),
 358          * which inserts foreign fences into intel_context.active, does not
 359          * clobber the idle-barrier.
 360          */
 361
 362         if (intel_engine_pm_is_awake(engine)) {
 363                 pr_err("%s is awake before starting %s!\n",
 364                        engine->name, __func__);
 365                 return -EINVAL;
 366         }
 367
 368         remote = intel_context_create(engine);
 369         if (IS_ERR(remote))
 370                 return PTR_ERR(remote);
 371
 372         local = intel_context_create(engine);
 373         if (IS_ERR(local)) {
 374                 err = PTR_ERR(local);
 375                 goto err_remote;
 376         }
 377
 378         saved_heartbeat = engine->props.heartbeat_interval_ms;
 379         engine->props.heartbeat_interval_ms = 0;
 380         intel_engine_pm_get(engine);
 381
 382         for (pass = 0; pass <= 2; pass++) {
 383                 err = __remote_sync(local, remote);
 384                 if (err)
 385                         break;
 386
 387                 err = __remote_sync(engine->kernel_context, remote);
 388                 if (err)
 389                         break;
 390
 391                 if (i915_active_is_idle(&remote->active)) {
 392                         pr_err("remote context is not active; expected idle-barrier (%s pass %d)\n",
 393                                engine->name, pass);
 394                         err = -EINVAL;
 395                         break;
 396                 }
 397         }
 398
 399         intel_engine_pm_put(engine);
 400         engine->props.heartbeat_interval_ms = saved_heartbeat;
 401
 402         intel_context_put(local);
 403 err_remote:
 404         intel_context_put(remote);
 405         return err;
 406 }
 407
 408 static int live_remote_context(void *arg)
 409 {
 410         struct intel_gt *gt = arg;
 411         struct intel_engine_cs *engine;
 412         enum intel_engine_id id;
 413         int err = 0;
 414
 415         for_each_engine(engine, gt, id) {
 416                 err = __live_remote_context(engine);
 417                 if (err)
 418                         break;
 419
 420                 err = igt_flush_test(gt->i915);
 421                 if (err)
 422                         break;
 423         }
 424
 425         return err;
 426 }
 427
 428 int intel_context_live_selftests(struct drm_i915_private *i915)
 429 {
 430         static const struct i915_subtest tests[] = {
 431                 SUBTEST(live_context_size),
 432                 SUBTEST(live_active_context),
 433                 SUBTEST(live_remote_context),
 434         };
 435         struct intel_gt *gt = &i915->gt;
 436
 437         if (intel_gt_is_wedged(gt))
 438                 return 0;
 439
 440         return intel_gt_live_subtests(tests, gt);
 441 }