drivers/gpu/drm/amd/scheduler/sched_fence.c

   1 /*
   2  * Copyright 2015 Advanced Micro Devices, Inc.
   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 shall be included in
  12  * all copies or substantial portions of the Software.
  13  *
  14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  17  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
  18  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  19  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  20  * OTHER DEALINGS IN THE SOFTWARE.
  21  *
  22  *
  23  */
  24 #include <linux/kthread.h>
  25 #include <linux/wait.h>
  26 #include <linux/sched.h>
  27 #include <drm/drmP.h>
  28 #include "gpu_scheduler.h"
  29
  30 struct amd_sched_fence *amd_sched_fence_create(struct amd_sched_entity *entity,
  31                                                void *owner)
  32 {
  33         struct amd_sched_fence *fence = NULL;
  34         unsigned seq;
  35
  36         fence = kmem_cache_zalloc(sched_fence_slab, GFP_KERNEL);
  37         if (fence == NULL)
  38                 return NULL;
  39
  40         INIT_LIST_HEAD(&fence->scheduled_cb);
  41         fence->owner = owner;
  42         fence->sched = entity->sched;
  43         spin_lock_init(&fence->lock);
  44
  45         seq = atomic_inc_return(&entity->fence_seq);
  46         fence_init(&fence->base, &amd_sched_fence_ops, &fence->lock,
  47                    entity->fence_context, seq);
  48
  49         return fence;
  50 }
  51
  52 void amd_sched_fence_signal(struct amd_sched_fence *fence)
  53 {
  54         int ret = fence_signal(&fence->base);
  55         if (!ret)
  56                 FENCE_TRACE(&fence->base, "signaled from irq context\n");
  57         else
  58                 FENCE_TRACE(&fence->base, "was already signaled\n");
  59 }
  60
  61 void amd_sched_job_pre_schedule(struct amd_gpu_scheduler *sched ,
  62                                 struct amd_sched_job *s_job)
  63 {
  64         unsigned long flags;
  65         spin_lock_irqsave(&sched->job_list_lock, flags);
  66         list_add_tail(&s_job->node, &sched->ring_mirror_list);
  67         sched->ops->begin_job(s_job);
  68         spin_unlock_irqrestore(&sched->job_list_lock, flags);
  69 }
  70
  71 void amd_sched_fence_scheduled(struct amd_sched_fence *s_fence)
  72 {
  73         struct fence_cb *cur, *tmp;
  74
  75         set_bit(AMD_SCHED_FENCE_SCHEDULED_BIT, &s_fence->base.flags);
  76         list_for_each_entry_safe(cur, tmp, &s_fence->scheduled_cb, node) {
  77                 list_del_init(&cur->node);
  78                 cur->func(&s_fence->base, cur);
  79         }
  80 }
  81
  82 static const char *amd_sched_fence_get_driver_name(struct fence *fence)
  83 {
  84         return "amd_sched";
  85 }
  86
  87 static const char *amd_sched_fence_get_timeline_name(struct fence *f)
  88 {
  89         struct amd_sched_fence *fence = to_amd_sched_fence(f);
  90         return (const char *)fence->sched->name;
  91 }
  92
  93 static bool amd_sched_fence_enable_signaling(struct fence *f)
  94 {
  95         return true;
  96 }
  97
  98 /**
  99  * amd_sched_fence_free - free up the fence memory
 100  *
 101  * @rcu: RCU callback head
 102  *
 103  * Free up the fence memory after the RCU grace period.
 104  */
 105 static void amd_sched_fence_free(struct rcu_head *rcu)
 106 {
 107         struct fence *f = container_of(rcu, struct fence, rcu);
 108         struct amd_sched_fence *fence = to_amd_sched_fence(f);
 109         kmem_cache_free(sched_fence_slab, fence);
 110 }
 111
 112 /**
 113  * amd_sched_fence_release - callback that fence can be freed
 114  *
 115  * @fence: fence
 116  *
 117  * This function is called when the reference count becomes zero.
 118  * It just RCU schedules freeing up the fence.
 119  */
 120 static void amd_sched_fence_release(struct fence *f)
 121 {
 122         call_rcu(&f->rcu, amd_sched_fence_free);
 123 }
 124
 125 const struct fence_ops amd_sched_fence_ops = {
 126         .get_driver_name = amd_sched_fence_get_driver_name,
 127         .get_timeline_name = amd_sched_fence_get_timeline_name,
 128         .enable_signaling = amd_sched_fence_enable_signaling,
 129         .signaled = NULL,
 130         .wait = fence_default_wait,
 131         .release = amd_sched_fence_release,
 132 };