drivers/gpu/drm/i915/selftests/i915_active.c

   1 /*
   2  * SPDX-License-Identifier: MIT
   3  *
   4  * Copyright © 2018 Intel Corporation
   5  */
   6
   7 #include <linux/kref.h>
   8
   9 #include "gem/i915_gem_pm.h"
  10 #include "gt/intel_gt.h"
  11
  12 #include "i915_selftest.h"
  13
  14 #include "igt_flush_test.h"
  15 #include "lib_sw_fence.h"
  16
  17 struct live_active {
  18         struct i915_active base;
  19         struct kref ref;
  20         bool retired;
  21 };
  22
  23 static void __live_get(struct live_active *active)
  24 {
  25         kref_get(&active->ref);
  26 }
  27
  28 static void __live_free(struct live_active *active)
  29 {
  30         i915_active_fini(&active->base);
  31         kfree(active);
  32 }
  33
  34 static void __live_release(struct kref *ref)
  35 {
  36         struct live_active *active = container_of(ref, typeof(*active), ref);
  37
  38         __live_free(active);
  39 }
  40
  41 static void __live_put(struct live_active *active)
  42 {
  43         kref_put(&active->ref, __live_release);
  44 }
  45
  46 static int __live_active(struct i915_active *base)
  47 {
  48         struct live_active *active = container_of(base, typeof(*active), base);
  49
  50         __live_get(active);
  51         return 0;
  52 }
  53
  54 static void __live_retire(struct i915_active *base)
  55 {
  56         struct live_active *active = container_of(base, typeof(*active), base);
  57
  58         active->retired = true;
  59         __live_put(active);
  60 }
  61
  62 static struct live_active *__live_alloc(struct drm_i915_private *i915)
  63 {
  64         struct live_active *active;
  65
  66         active = kzalloc(sizeof(*active), GFP_KERNEL);
  67         if (!active)
  68                 return NULL;
  69
  70         kref_init(&active->ref);
  71         i915_active_init(&active->base, __live_active, __live_retire);
  72
  73         return active;
  74 }
  75
  76 static struct live_active *
  77 __live_active_setup(struct drm_i915_private *i915)
  78 {
  79         struct intel_engine_cs *engine;
  80         struct i915_sw_fence *submit;
  81         struct live_active *active;
  82         unsigned int count = 0;
  83         int err = 0;
  84
  85         active = __live_alloc(i915);
  86         if (!active)
  87                 return ERR_PTR(-ENOMEM);
  88
  89         submit = heap_fence_create(GFP_KERNEL);
  90         if (!submit) {
  91                 kfree(active);
  92                 return ERR_PTR(-ENOMEM);
  93         }
  94
  95         err = i915_active_acquire(&active->base);
  96         if (err)
  97                 goto out;
  98
  99         for_each_uabi_engine(engine, i915) {
 100                 struct i915_request *rq;
 101
 102                 rq = intel_engine_create_kernel_request(engine);
 103                 if (IS_ERR(rq)) {
 104                         err = PTR_ERR(rq);
 105                         break;
 106                 }
 107
 108                 err = i915_sw_fence_await_sw_fence_gfp(&rq->submit,
 109                                                        submit,
 110                                                        GFP_KERNEL);
 111                 if (err >= 0)
 112                         err = i915_active_add_request(&active->base, rq);
 113                 i915_request_add(rq);
 114                 if (err) {
 115                         pr_err("Failed to track active ref!\n");
 116                         break;
 117                 }
 118
 119                 count++;
 120         }
 121
 122         i915_active_release(&active->base);
 123         if (READ_ONCE(active->retired) && count) {
 124                 pr_err("i915_active retired before submission!\n");
 125                 err = -EINVAL;
 126         }
 127         if (atomic_read(&active->base.count) != count) {
 128                 pr_err("i915_active not tracking all requests, found %d, expected %d\n",
 129                        atomic_read(&active->base.count), count);
 130                 err = -EINVAL;
 131         }
 132
 133 out:
 134         i915_sw_fence_commit(submit);
 135         heap_fence_put(submit);
 136         if (err) {
 137                 __live_put(active);
 138                 active = ERR_PTR(err);
 139         }
 140
 141         return active;
 142 }
 143
 144 static int live_active_wait(void *arg)
 145 {
 146         struct drm_i915_private *i915 = arg;
 147         struct live_active *active;
 148         int err = 0;
 149
 150         /* Check that we get a callback when requests retire upon waiting */
 151
 152         active = __live_active_setup(i915);
 153         if (IS_ERR(active))
 154                 return PTR_ERR(active);
 155
 156         i915_active_wait(&active->base);
 157         if (!READ_ONCE(active->retired)) {
 158                 struct drm_printer p = drm_err_printer(__func__);
 159
 160                 pr_err("i915_active not retired after waiting!\n");
 161                 i915_active_print(&active->base, &p);
 162
 163                 err = -EINVAL;
 164         }
 165
 166         __live_put(active);
 167
 168         if (igt_flush_test(i915))
 169                 err = -EIO;
 170
 171         return err;
 172 }
 173
 174 static int live_active_retire(void *arg)
 175 {
 176         struct drm_i915_private *i915 = arg;
 177         struct live_active *active;
 178         int err = 0;
 179
 180         /* Check that we get a callback when requests are indirectly retired */
 181
 182         active = __live_active_setup(i915);
 183         if (IS_ERR(active))
 184                 return PTR_ERR(active);
 185
 186         /* waits for & retires all requests */
 187         if (igt_flush_test(i915))
 188                 err = -EIO;
 189
 190         if (!READ_ONCE(active->retired)) {
 191                 struct drm_printer p = drm_err_printer(__func__);
 192
 193                 pr_err("i915_active not retired after flushing!\n");
 194                 i915_active_print(&active->base, &p);
 195
 196                 err = -EINVAL;
 197         }
 198
 199         __live_put(active);
 200
 201         return err;
 202 }
 203
 204 static int live_active_barrier(void *arg)
 205 {
 206         struct drm_i915_private *i915 = arg;
 207         struct intel_engine_cs *engine;
 208         struct live_active *active;
 209         int err = 0;
 210
 211         /* Check that we get a callback when requests retire upon waiting */
 212
 213         active = __live_alloc(i915);
 214         if (!active)
 215                 return -ENOMEM;
 216
 217         err = i915_active_acquire(&active->base);
 218         if (err)
 219                 goto out;
 220
 221         for_each_uabi_engine(engine, i915) {
 222                 err = i915_active_acquire_preallocate_barrier(&active->base,
 223                                                               engine);
 224                 if (err)
 225                         break;
 226
 227                 i915_active_acquire_barrier(&active->base);
 228         }
 229
 230         i915_active_release(&active->base);
 231
 232         if (err == 0)
 233                 err = i915_active_wait(&active->base);
 234
 235         if (err == 0 && !READ_ONCE(active->retired)) {
 236                 pr_err("i915_active not retired after flushing barriers!\n");
 237                 err = -EINVAL;
 238         }
 239
 240 out:
 241         __live_put(active);
 242
 243         if (igt_flush_test(i915))
 244                 err = -EIO;
 245
 246         return err;
 247 }
 248
 249 int i915_active_live_selftests(struct drm_i915_private *i915)
 250 {
 251         static const struct i915_subtest tests[] = {
 252                 SUBTEST(live_active_wait),
 253                 SUBTEST(live_active_retire),
 254                 SUBTEST(live_active_barrier),
 255         };
 256
 257         if (intel_gt_is_wedged(&i915->gt))
 258                 return 0;
 259
 260         return i915_subtests(tests, i915);
 261 }
 262
 263 static struct intel_engine_cs *node_to_barrier(struct active_node *it)
 264 {
 265         struct intel_engine_cs *engine;
 266
 267         if (!is_barrier(&it->base))
 268                 return NULL;
 269
 270         engine = __barrier_to_engine(it);
 271         smp_rmb(); /* serialise with add_active_barriers */
 272         if (!is_barrier(&it->base))
 273                 return NULL;
 274
 275         return engine;
 276 }
 277
 278 void i915_active_print(struct i915_active *ref, struct drm_printer *m)
 279 {
 280         drm_printf(m, "active %pS:%pS\n", ref->active, ref->retire);
 281         drm_printf(m, "\tcount: %d\n", atomic_read(&ref->count));
 282         drm_printf(m, "\tpreallocated barriers? %s\n",
 283                    yesno(!llist_empty(&ref->preallocated_barriers)));
 284
 285         if (i915_active_acquire_if_busy(ref)) {
 286                 struct active_node *it, *n;
 287
 288                 rbtree_postorder_for_each_entry_safe(it, n, &ref->tree, node) {
 289                         struct intel_engine_cs *engine;
 290
 291                         engine = node_to_barrier(it);
 292                         if (engine) {
 293                                 drm_printf(m, "\tbarrier: %s\n", engine->name);
 294                                 continue;
 295                         }
 296
 297                         if (i915_active_fence_isset(&it->base)) {
 298                                 drm_printf(m,
 299                                            "\ttimeline: %llx\n", it->timeline);
 300                                 continue;
 301                         }
 302                 }
 303
 304                 i915_active_release(ref);
 305         }
 306 }
 307
 308 static void spin_unlock_wait(spinlock_t *lock)
 309 {
 310         spin_lock_irq(lock);
 311         spin_unlock_irq(lock);
 312 }
 313
 314 static void active_flush(struct i915_active *ref,
 315                          struct i915_active_fence *active)
 316 {
 317         struct dma_fence *fence;
 318
 319         fence = xchg(__active_fence_slot(active), NULL);
 320         if (!fence)
 321                 return;
 322
 323         spin_lock_irq(fence->lock);
 324         __list_del_entry(&active->cb.node);
 325         spin_unlock_irq(fence->lock); /* serialise with fence->cb_list */
 326         atomic_dec(&ref->count);
 327
 328         GEM_BUG_ON(!test_bit(DMA_FENCE_FLAG_SIGNALED_BIT, &fence->flags));
 329 }
 330
 331 void i915_active_unlock_wait(struct i915_active *ref)
 332 {
 333         if (i915_active_acquire_if_busy(ref)) {
 334                 struct active_node *it, *n;
 335
 336                 /* Wait for all active callbacks */
 337                 rcu_read_lock();
 338                 active_flush(ref, &ref->excl);
 339                 rbtree_postorder_for_each_entry_safe(it, n, &ref->tree, node)
 340                         active_flush(ref, &it->base);
 341                 rcu_read_unlock();
 342
 343                 i915_active_release(ref);
 344         }
 345
 346         /* And wait for the retire callback */
 347         spin_unlock_wait(&ref->tree_lock);
 348
 349         /* ... which may have been on a thread instead */
 350         flush_work(&ref->work);
 351 }