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

   1 /*
   2  * Copyright © 2017 Intel Corporation
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a
   5  * copy of this software and associated documentation files (the "Software"),
   6  * to deal in the Software without restriction, including without limitation
   7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   8  * and/or sell copies of the Software, and to permit persons to whom the
   9  * Software is furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice (including the next
  12  * paragraph) shall be included in all copies or substantial portions of the
  13  * Software.
  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 NONINFRINGEMENT.  IN NO EVENT SHALL
  18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
  21  * IN THE SOFTWARE.
  22  *
  23  */
  24
  25 #include "lib_sw_fence.h"
  26
  27 /* Small library of different fence types useful for writing tests */
  28
  29 static int __i915_sw_fence_call
  30 nop_fence_notify(struct i915_sw_fence *fence, enum i915_sw_fence_notify state)
  31 {
  32         return NOTIFY_DONE;
  33 }
  34
  35 void __onstack_fence_init(struct i915_sw_fence *fence,
  36                           const char *name,
  37                           struct lock_class_key *key)
  38 {
  39         debug_fence_init_onstack(fence);
  40
  41         __init_waitqueue_head(&fence->wait, name, key);
  42         atomic_set(&fence->pending, 1);
  43         fence->error = 0;
  44         fence->flags = (unsigned long)nop_fence_notify;
  45 }
  46
  47 void onstack_fence_fini(struct i915_sw_fence *fence)
  48 {
  49         if (!fence->flags)
  50                 return;
  51
  52         i915_sw_fence_commit(fence);
  53         i915_sw_fence_fini(fence);
  54 }
  55
  56 static void timed_fence_wake(struct timer_list *t)
  57 {
  58         struct timed_fence *tf = from_timer(tf, t, timer);
  59
  60         i915_sw_fence_commit(&tf->fence);
  61 }
  62
  63 void timed_fence_init(struct timed_fence *tf, unsigned long expires)
  64 {
  65         onstack_fence_init(&tf->fence);
  66
  67         timer_setup_on_stack(&tf->timer, timed_fence_wake, 0);
  68
  69         if (time_after(expires, jiffies))
  70                 mod_timer(&tf->timer, expires);
  71         else
  72                 i915_sw_fence_commit(&tf->fence);
  73 }
  74
  75 void timed_fence_fini(struct timed_fence *tf)
  76 {
  77         if (del_timer_sync(&tf->timer))
  78                 i915_sw_fence_commit(&tf->fence);
  79
  80         destroy_timer_on_stack(&tf->timer);
  81         i915_sw_fence_fini(&tf->fence);
  82 }
  83
  84 struct heap_fence {
  85         struct i915_sw_fence fence;
  86         union {
  87                 struct kref ref;
  88                 struct rcu_head rcu;
  89         };
  90 };
  91
  92 static int __i915_sw_fence_call
  93 heap_fence_notify(struct i915_sw_fence *fence, enum i915_sw_fence_notify state)
  94 {
  95         struct heap_fence *h = container_of(fence, typeof(*h), fence);
  96
  97         switch (state) {
  98         case FENCE_COMPLETE:
  99                 break;
 100
 101         case FENCE_FREE:
 102                 heap_fence_put(&h->fence);
 103         }
 104
 105         return NOTIFY_DONE;
 106 }
 107
 108 struct i915_sw_fence *heap_fence_create(gfp_t gfp)
 109 {
 110         struct heap_fence *h;
 111
 112         h = kmalloc(sizeof(*h), gfp);
 113         if (!h)
 114                 return NULL;
 115
 116         i915_sw_fence_init(&h->fence, heap_fence_notify);
 117         refcount_set(&h->ref.refcount, 2);
 118
 119         return &h->fence;
 120 }
 121
 122 static void heap_fence_release(struct kref *ref)
 123 {
 124         struct heap_fence *h = container_of(ref, typeof(*h), ref);
 125
 126         i915_sw_fence_fini(&h->fence);
 127
 128         kfree_rcu(h, rcu);
 129 }
 130
 131 void heap_fence_put(struct i915_sw_fence *fence)
 132 {
 133         struct heap_fence *h = container_of(fence, typeof(*h), fence);
 134
 135         kref_put(&h->ref, heap_fence_release);
 136 }