Am 13.04.2018 um 09:01 schrieb Emily Deng:
> issue:
> there are VMC page fault occurred if force APP kill during
> 3dmark test, the cause is in entity_fini we manually signal
> all those jobs in entity's queue which confuse the sync/dep
> mechanism:
>
> 1)page fault occurred in sdma's clear job which operate on
> shadow buffer, and shadow buffer's Gart table is cleaned by
> ttm_bo_release since the fence in its reservation was fake signaled
> by entity_fini() under the case of SIGKILL received.
>
> 2)page fault occurred in gfx' job because during the lifetime
> of gfx job we manually fake signal all jobs from its entity
> in entity_fini(), thus the unmapping/clear PTE job depend on those
> result fence is satisfied and sdma start clearing the PTE and lead
> to GFX page fault.
>
> fix:
> 1)should at least wait all jobs already scheduled complete in entity_fini()
> if SIGKILL is the case.
>
> 2)if a fence signaled and try to clear some entity's dependency, should
> set this entity guilty to prevent its job really run since the dependency
> is fake signaled.
>
> v2:
> splitting drm_sched_entity_fini() into two functions:
> 1)The first one is does the waiting, removes the entity from the
> runqueue and returns an error when the process was killed.
> 2)The second one then goes over the entity, install it as
> completion signal for the remaining jobs and signals all jobs
> with an error code.
>
> v3:
> 1)Replace the fini1 and fini2 with better name
> 2)Call the first part before the VM teardown in
> amdgpu_driver_postclose_kms() and the second part
> after the VM teardown
> 3)Keep the original function drm_sched_entity_fini to
> refine the code.
>
> v4:
> 1)Rename entity->finished to entity->last_scheduled;
> 2)Rename drm_sched_entity_fini_job_cb() to
> drm_sched_entity_kill_jobs_cb();
> 3)Pass NULL to drm_sched_entity_fini_job_cb() if -ENOENT;
> 4)Replace the type of entity->fini_status with "int";
> 5)Remove the check about entity->finished.
>
> Signed-off-by: Monk Liu <Monk.Liu at amd.com>
> Signed-off-by: Emily Deng <Emily.Deng at amd.com>
At least of hand that looks really good.
Patch is Reviewed-by: Christian König <christian.koenig at amd.com>.
Andrey, David you guys also recently hacked on the scheduler, so can
please take a look as well?
Thanks,
Christian.
> ---
> drivers/gpu/drm/amd/amdgpu/amdgpu.h | 2 +
> drivers/gpu/drm/amd/amdgpu/amdgpu_ctx.c | 64 ++++++++++++++++++++++++----
> drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c | 5 ++-
> drivers/gpu/drm/scheduler/gpu_scheduler.c | 71 ++++++++++++++++++++++++++-----
> include/drm/gpu_scheduler.h | 7 +++
> 5 files changed, 128 insertions(+), 21 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
> index 5734871..b3d047d 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
> @@ -681,6 +681,8 @@ int amdgpu_ctx_ioctl(struct drm_device *dev, void *data,
> int amdgpu_ctx_wait_prev_fence(struct amdgpu_ctx *ctx, unsigned ring_id);
>
> void amdgpu_ctx_mgr_init(struct amdgpu_ctx_mgr *mgr);
> +void amdgpu_ctx_mgr_entity_cleanup(struct amdgpu_ctx_mgr *mgr);
> +void amdgpu_ctx_mgr_entity_fini(struct amdgpu_ctx_mgr *mgr);
> void amdgpu_ctx_mgr_fini(struct amdgpu_ctx_mgr *mgr);
>
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ctx.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ctx.c
> index 09d35051..eb80edf 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ctx.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ctx.c
> @@ -111,8 +111,9 @@ static int amdgpu_ctx_init(struct amdgpu_device *adev,
> return r;
> }
>
> -static void amdgpu_ctx_fini(struct amdgpu_ctx *ctx)
> +static void amdgpu_ctx_fini(struct kref *ref)
> {
> + struct amdgpu_ctx *ctx = container_of(ref, struct amdgpu_ctx, refcount);
> struct amdgpu_device *adev = ctx->adev;
> unsigned i, j;
>
> @@ -125,13 +126,11 @@ static void amdgpu_ctx_fini(struct amdgpu_ctx *ctx)
> kfree(ctx->fences);
> ctx->fences = NULL;
>
> - for (i = 0; i < adev->num_rings; i++)
> - drm_sched_entity_fini(&adev->rings[i]->sched,
> - &ctx->rings[i].entity);
> -
> amdgpu_queue_mgr_fini(adev, &ctx->queue_mgr);
>
> mutex_destroy(&ctx->lock);
> +
> + kfree(ctx);
> }
>
> static int amdgpu_ctx_alloc(struct amdgpu_device *adev,
> @@ -170,12 +169,15 @@ static int amdgpu_ctx_alloc(struct amdgpu_device *adev,
> static void amdgpu_ctx_do_release(struct kref *ref)
> {
> struct amdgpu_ctx *ctx;
> + u32 i;
>
> ctx = container_of(ref, struct amdgpu_ctx, refcount);
>
> - amdgpu_ctx_fini(ctx);
> + for (i = 0; i < ctx->adev->num_rings; i++)
> + drm_sched_entity_fini(&ctx->adev->rings[i]->sched,
> + &ctx->rings[i].entity);
>
> - kfree(ctx);
> + amdgpu_ctx_fini(ref);
> }
>
> static int amdgpu_ctx_free(struct amdgpu_fpriv *fpriv, uint32_t id)
> @@ -435,16 +437,62 @@ void amdgpu_ctx_mgr_init(struct amdgpu_ctx_mgr *mgr)
> idr_init(&mgr->ctx_handles);
> }
>
> +void amdgpu_ctx_mgr_entity_fini(struct amdgpu_ctx_mgr *mgr)
> +{
> + struct amdgpu_ctx *ctx;
> + struct idr *idp;
> + uint32_t id, i;
> +
> + idp = &mgr->ctx_handles;
> +
> + idr_for_each_entry(idp, ctx, id) {
> +
> + if (!ctx->adev)
> + return;
> +
> + for (i = 0; i < ctx->adev->num_rings; i++)
> + if (kref_read(&ctx->refcount) == 1)
> + drm_sched_entity_do_release(&ctx->adev->rings[i]->sched,
> + &ctx->rings[i].entity);
> + else
> + DRM_ERROR("ctx %p is still alive\n", ctx);
> + }
> +}
> +
> +void amdgpu_ctx_mgr_entity_cleanup(struct amdgpu_ctx_mgr *mgr)
> +{
> + struct amdgpu_ctx *ctx;
> + struct idr *idp;
> + uint32_t id, i;
> +
> + idp = &mgr->ctx_handles;
> +
> + idr_for_each_entry(idp, ctx, id) {
> +
> + if (!ctx->adev)
> + return;
> +
> + for (i = 0; i < ctx->adev->num_rings; i++)
> + if (kref_read(&ctx->refcount) == 1)
> + drm_sched_entity_cleanup(&ctx->adev->rings[i]->sched,
> + &ctx->rings[i].entity);
> + else
> + DRM_ERROR("ctx %p is still alive\n", ctx);
> + }
> +}
> +
> void amdgpu_ctx_mgr_fini(struct amdgpu_ctx_mgr *mgr)
> {
> struct amdgpu_ctx *ctx;
> struct idr *idp;
> uint32_t id;
>
> + amdgpu_ctx_mgr_entity_cleanup(mgr);
> +
> idp = &mgr->ctx_handles;
>
> idr_for_each_entry(idp, ctx, id) {
> - if (kref_put(&ctx->refcount, amdgpu_ctx_do_release) != 1)
> + if (kref_put(&ctx->refcount, amdgpu_ctx_fini) != 1)
> DRM_ERROR("ctx %p is still alive\n", ctx);
> }
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
> index 487d39e..6cbb427 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
> @@ -913,8 +913,7 @@ void amdgpu_driver_postclose_kms(struct drm_device *dev,
> return;
>
> pm_runtime_get_sync(dev->dev);
> -
> - amdgpu_ctx_mgr_fini(&fpriv->ctx_mgr);
> + amdgpu_ctx_mgr_entity_fini(&fpriv->ctx_mgr);
>
> if (adev->asic_type != CHIP_RAVEN) {
> amdgpu_uvd_free_handles(adev, file_priv);
> @@ -935,6 +934,8 @@ void amdgpu_driver_postclose_kms(struct drm_device *dev,
> pd = amdgpu_bo_ref(fpriv->vm.root.base.bo);
>
> amdgpu_vm_fini(adev, &fpriv->vm);
> + amdgpu_ctx_mgr_fini(&fpriv->ctx_mgr);
> +
> if (pasid)
> amdgpu_pasid_free_delayed(pd->tbo.resv, pasid);
> amdgpu_bo_unref(&pd);
> diff --git a/drivers/gpu/drm/scheduler/gpu_scheduler.c b/drivers/gpu/drm/scheduler/gpu_scheduler.c
> index 310275e..44d2198 100644
> --- a/drivers/gpu/drm/scheduler/gpu_scheduler.c
> +++ b/drivers/gpu/drm/scheduler/gpu_scheduler.c
> @@ -136,6 +136,8 @@ int drm_sched_entity_init(struct drm_gpu_scheduler *sched,
> entity->rq = rq;
> entity->sched = sched;
> entity->guilty = guilty;
> + entity->fini_status = 0;
> + entity->last_scheduled = NULL;
>
> spin_lock_init(&entity->rq_lock);
> spin_lock_init(&entity->queue_lock);
> @@ -197,19 +199,30 @@ static bool drm_sched_entity_is_ready(struct drm_sched_entity *entity)
> return true;
> }
>
> +static void drm_sched_entity_kill_jobs_cb(struct dma_fence *f,
> + struct dma_fence_cb *cb)
> +{
> + struct drm_sched_job *job = container_of(cb, struct drm_sched_job,
> + finish_cb);
> + drm_sched_fence_finished(job->s_fence);
> + WARN_ON(job->s_fence->parent);
> + dma_fence_put(&job->s_fence->finished);
> + job->sched->ops->free_job(job);
> +}
> +
> +
> /**
> * Destroy a context entity
> *
> * @sched Pointer to scheduler instance
> * @entity The pointer to a valid scheduler entity
> *
> - * Cleanup and free the allocated resources.
> + * Splitting drm_sched_entity_fini() into two functions, The first one is does the waiting,
> + * removes the entity from the runqueue and returns an error when the process was killed.
> */
> -void drm_sched_entity_fini(struct drm_gpu_scheduler *sched,
> +void drm_sched_entity_do_release(struct drm_gpu_scheduler *sched,
> struct drm_sched_entity *entity)
> {
> - int r;
> -
> if (!drm_sched_entity_is_initialized(sched, entity))
> return;
> /**
> @@ -217,13 +230,28 @@ void drm_sched_entity_fini(struct drm_gpu_scheduler *sched,
> * queued IBs or discard them on SIGKILL
> */
> if ((current->flags & PF_SIGNALED) && current->exit_code == SIGKILL)
> - r = -ERESTARTSYS;
> + entity->fini_status = -ERESTARTSYS;
> else
> - r = wait_event_killable(sched->job_scheduled,
> + entity->fini_status = wait_event_killable(sched->job_scheduled,
> drm_sched_entity_is_idle(entity));
> drm_sched_entity_set_rq(entity, NULL);
> - if (r) {
> +}
> +EXPORT_SYMBOL(drm_sched_entity_do_release);
> +
> +/**
> + * Destroy a context entity
> + *
> + * @sched Pointer to scheduler instance
> + * @entity The pointer to a valid scheduler entity
> + *
> + * The second one then goes over the entity and signals all jobs with an error code.
> + */
> +void drm_sched_entity_cleanup(struct drm_gpu_scheduler *sched,
> + struct drm_sched_entity *entity)
> +{
> + if (entity->fini_status) {
> struct drm_sched_job *job;
> + int r;
>
> /* Park the kernel for a moment to make sure it isn't processing
> * our enity.
> @@ -241,13 +269,26 @@ void drm_sched_entity_fini(struct drm_gpu_scheduler *sched,
> struct drm_sched_fence *s_fence = job->s_fence;
> drm_sched_fence_scheduled(s_fence);
> dma_fence_set_error(&s_fence->finished, -ESRCH);
> - drm_sched_fence_finished(s_fence);
> - WARN_ON(s_fence->parent);
> - dma_fence_put(&s_fence->finished);
> - sched->ops->free_job(job);
> + r = dma_fence_add_callback(entity->last_scheduled, &job->finish_cb,
> + drm_sched_entity_kill_jobs_cb);
> + if (r == -ENOENT)
> + drm_sched_entity_kill_jobs_cb(NULL, &job->finish_cb);
> + else if (r)
> + DRM_ERROR("fence add callback failed (%d)\n", r);
> }
> +
> + dma_fence_put(entity->last_scheduled);
> + entity->last_scheduled = NULL;
> }
> }
> +EXPORT_SYMBOL(drm_sched_entity_cleanup);
> +
> +void drm_sched_entity_fini(struct drm_gpu_scheduler *sched,
> + struct drm_sched_entity *entity)
> +{
> + drm_sched_entity_do_release(sched, entity);
> + drm_sched_entity_cleanup(sched, entity);
> +}
> EXPORT_SYMBOL(drm_sched_entity_fini);
>
> static void drm_sched_entity_wakeup(struct dma_fence *f, struct dma_fence_cb *cb)
> @@ -530,6 +571,10 @@ void drm_sched_job_recovery(struct drm_gpu_scheduler *sched)
> spin_unlock(&sched->job_list_lock);
> fence = sched->ops->run_job(s_job);
> atomic_inc(&sched->hw_rq_count);
> +
> + dma_fence_put(s_job->entity->last_scheduled);
> + s_job->entity->last_scheduled = dma_fence_get(&s_fence->finished);
> +
> if (fence) {
> s_fence->parent = dma_fence_get(fence);
> r = dma_fence_add_callback(fence, &s_fence->cb,
> @@ -556,6 +601,7 @@ int drm_sched_job_init(struct drm_sched_job *job,
> void *owner)
> {
> job->sched = sched;
> + job->entity = entity;
> job->s_priority = entity->rq - sched->sched_rq;
> job->s_fence = drm_sched_fence_create(entity, owner);
> if (!job->s_fence)
> @@ -669,6 +715,9 @@ static int drm_sched_main(void *param)
> fence = sched->ops->run_job(sched_job);
> drm_sched_fence_scheduled(s_fence);
>
> + dma_fence_put(entity->last_scheduled);
> + entity->last_scheduled = dma_fence_get(&s_fence->finished);
> +
> if (fence) {
> s_fence->parent = dma_fence_get(fence);
> r = dma_fence_add_callback(fence, &s_fence->cb,
> diff --git a/include/drm/gpu_scheduler.h b/include/drm/gpu_scheduler.h
> index c053a32..350a62c 100644
> --- a/include/drm/gpu_scheduler.h
> +++ b/include/drm/gpu_scheduler.h
> @@ -65,6 +65,8 @@ struct drm_sched_entity {
> struct dma_fence *dependency;
> struct dma_fence_cb cb;
> atomic_t *guilty; /* points to ctx's guilty */
> + int fini_status;
> + struct dma_fence *last_scheduled;
> };
>
> /**
> @@ -119,6 +121,7 @@ struct drm_sched_job {
> uint64_t id;
> atomic_t karma;
> enum drm_sched_priority s_priority;
> + struct drm_sched_entity *entity;
> };
>
> static inline bool drm_sched_invalidate_job(struct drm_sched_job *s_job,
> @@ -186,6 +189,10 @@ int drm_sched_entity_init(struct drm_gpu_scheduler *sched,
> struct drm_sched_entity *entity,
> struct drm_sched_rq *rq,
> uint32_t jobs, atomic_t *guilty);
> +void drm_sched_entity_do_release(struct drm_gpu_scheduler *sched,
> + struct drm_sched_entity *entity);
> +void drm_sched_entity_cleanup(struct drm_gpu_scheduler *sched,
> + struct drm_sched_entity *entity);
> void drm_sched_entity_fini(struct drm_gpu_scheduler *sched,
> struct drm_sched_entity *entity);
> void drm_sched_entity_push_job(struct drm_sched_job *sched_job,
