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-rw-r--r--drivers/gpu/drm/scheduler/.kunitconfig12
-rw-r--r--drivers/gpu/drm/scheduler/Makefile27
-rw-r--r--drivers/gpu/drm/scheduler/gpu_scheduler_trace.h159
-rw-r--r--drivers/gpu/drm/scheduler/sched_entity.c631
-rw-r--r--drivers/gpu/drm/scheduler/sched_fence.c242
-rw-r--r--drivers/gpu/drm/scheduler/sched_internal.h91
-rw-r--r--drivers/gpu/drm/scheduler/sched_main.c1569
-rw-r--r--drivers/gpu/drm/scheduler/tests/Makefile7
-rw-r--r--drivers/gpu/drm/scheduler/tests/mock_scheduler.c370
-rw-r--r--drivers/gpu/drm/scheduler/tests/sched_tests.h224
-rw-r--r--drivers/gpu/drm/scheduler/tests/tests_basic.c563
11 files changed, 3895 insertions, 0 deletions
diff --git a/drivers/gpu/drm/scheduler/.kunitconfig b/drivers/gpu/drm/scheduler/.kunitconfig
new file mode 100644
index 000000000000..cece53609fcf
--- /dev/null
+++ b/drivers/gpu/drm/scheduler/.kunitconfig
@@ -0,0 +1,12 @@
+CONFIG_KUNIT=y
+CONFIG_DRM=y
+CONFIG_DRM_SCHED_KUNIT_TEST=y
+CONFIG_EXPERT=y
+CONFIG_DEBUG_SPINLOCK=y
+CONFIG_DEBUG_MUTEXES=y
+CONFIG_DEBUG_ATOMIC_SLEEP=y
+CONFIG_LOCK_DEBUGGING_SUPPORT=y
+CONFIG_PROVE_LOCKING=y
+CONFIG_LOCKDEP=y
+CONFIG_DEBUG_LOCKDEP=y
+CONFIG_DEBUG_LIST=y
diff --git a/drivers/gpu/drm/scheduler/Makefile b/drivers/gpu/drm/scheduler/Makefile
new file mode 100644
index 000000000000..6e13e4c63e9d
--- /dev/null
+++ b/drivers/gpu/drm/scheduler/Makefile
@@ -0,0 +1,27 @@
+#
+# Copyright 2017 Advanced Micro Devices, Inc.
+#
+# Permission is hereby granted, free of charge, to any person obtaining a
+# copy of this software and associated documentation files (the "Software"),
+# to deal in the Software without restriction, including without limitation
+# the rights to use, copy, modify, merge, publish, distribute, sublicense,
+# and/or sell copies of the Software, and to permit persons to whom the
+# Software is furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in
+# all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+# THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+# OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+# ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+# OTHER DEALINGS IN THE SOFTWARE.
+#
+#
+gpu-sched-y := sched_main.o sched_fence.o sched_entity.o
+
+obj-$(CONFIG_DRM_SCHED) += gpu-sched.o
+
+obj-$(CONFIG_DRM_SCHED_KUNIT_TEST) += tests/
diff --git a/drivers/gpu/drm/scheduler/gpu_scheduler_trace.h b/drivers/gpu/drm/scheduler/gpu_scheduler_trace.h
new file mode 100644
index 000000000000..261713dd7d5a
--- /dev/null
+++ b/drivers/gpu/drm/scheduler/gpu_scheduler_trace.h
@@ -0,0 +1,159 @@
+/*
+ * Copyright 2017 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ */
+
+#if !defined(_GPU_SCHED_TRACE_H_) || defined(TRACE_HEADER_MULTI_READ)
+#define _GPU_SCHED_TRACE_H_
+
+#include <linux/stringify.h>
+#include <linux/types.h>
+#include <linux/tracepoint.h>
+
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM gpu_scheduler
+#define TRACE_INCLUDE_FILE gpu_scheduler_trace
+
+/**
+ * DOC: uAPI trace events
+ *
+ * ``drm_sched_job_queue``, ``drm_sched_job_run``, ``drm_sched_job_add_dep``,
+ * ``drm_sched_job_done`` and ``drm_sched_job_unschedulable`` are considered
+ * stable uAPI.
+ *
+ * Common trace events attributes:
+ *
+ * * ``dev`` - the dev_name() of the device running the job.
+ *
+ * * ``ring`` - the hardware ring running the job. Together with ``dev`` it
+ * uniquely identifies where the job is going to be executed.
+ *
+ * * ``fence`` - the &struct dma_fence.context and the &struct dma_fence.seqno of
+ * &struct drm_sched_fence.finished
+ *
+ * All the events depends on drm_sched_job_arm() having been called already for
+ * the job because they use &struct drm_sched_job.sched or
+ * &struct drm_sched_job.s_fence.
+ */
+
+DECLARE_EVENT_CLASS(drm_sched_job,
+ TP_PROTO(struct drm_sched_job *sched_job, struct drm_sched_entity *entity),
+ TP_ARGS(sched_job, entity),
+ TP_STRUCT__entry(
+ __string(name, sched_job->sched->name)
+ __field(u32, job_count)
+ __field(int, hw_job_count)
+ __string(dev, dev_name(sched_job->sched->dev))
+ __field(u64, fence_context)
+ __field(u64, fence_seqno)
+ __field(u64, client_id)
+ ),
+
+ TP_fast_assign(
+ __assign_str(name);
+ __entry->job_count = spsc_queue_count(&entity->job_queue);
+ __entry->hw_job_count = atomic_read(
+ &sched_job->sched->credit_count);
+ __assign_str(dev);
+ __entry->fence_context = sched_job->s_fence->finished.context;
+ __entry->fence_seqno = sched_job->s_fence->finished.seqno;
+ __entry->client_id = sched_job->s_fence->drm_client_id;
+ ),
+ TP_printk("dev=%s, fence=%llu:%llu, ring=%s, job count:%u, hw job count:%d, client_id:%llu",
+ __get_str(dev),
+ __entry->fence_context, __entry->fence_seqno, __get_str(name),
+ __entry->job_count, __entry->hw_job_count, __entry->client_id)
+);
+
+DEFINE_EVENT(drm_sched_job, drm_sched_job_queue,
+ TP_PROTO(struct drm_sched_job *sched_job, struct drm_sched_entity *entity),
+ TP_ARGS(sched_job, entity)
+);
+
+DEFINE_EVENT(drm_sched_job, drm_sched_job_run,
+ TP_PROTO(struct drm_sched_job *sched_job, struct drm_sched_entity *entity),
+ TP_ARGS(sched_job, entity)
+);
+
+TRACE_EVENT(drm_sched_job_done,
+ TP_PROTO(struct drm_sched_fence *fence),
+ TP_ARGS(fence),
+ TP_STRUCT__entry(
+ __field(u64, fence_context)
+ __field(u64, fence_seqno)
+ ),
+
+ TP_fast_assign(
+ __entry->fence_context = fence->finished.context;
+ __entry->fence_seqno = fence->finished.seqno;
+ ),
+ TP_printk("fence=%llu:%llu signaled",
+ __entry->fence_context, __entry->fence_seqno)
+);
+
+TRACE_EVENT(drm_sched_job_add_dep,
+ TP_PROTO(struct drm_sched_job *sched_job, struct dma_fence *fence),
+ TP_ARGS(sched_job, fence),
+ TP_STRUCT__entry(
+ __field(u64, fence_context)
+ __field(u64, fence_seqno)
+ __field(u64, ctx)
+ __field(u64, seqno)
+ ),
+
+ TP_fast_assign(
+ __entry->fence_context = sched_job->s_fence->finished.context;
+ __entry->fence_seqno = sched_job->s_fence->finished.seqno;
+ __entry->ctx = fence->context;
+ __entry->seqno = fence->seqno;
+ ),
+ TP_printk("fence=%llu:%llu depends on fence=%llu:%llu",
+ __entry->fence_context, __entry->fence_seqno,
+ __entry->ctx, __entry->seqno)
+);
+
+TRACE_EVENT(drm_sched_job_unschedulable,
+ TP_PROTO(struct drm_sched_job *sched_job, struct dma_fence *fence),
+ TP_ARGS(sched_job, fence),
+ TP_STRUCT__entry(
+ __field(u64, fence_context)
+ __field(u64, fence_seqno)
+ __field(u64, ctx)
+ __field(u64, seqno)
+ ),
+
+ TP_fast_assign(
+ __entry->fence_context = sched_job->s_fence->finished.context;
+ __entry->fence_seqno = sched_job->s_fence->finished.seqno;
+ __entry->ctx = fence->context;
+ __entry->seqno = fence->seqno;
+ ),
+ TP_printk("fence=%llu:%llu depends on unsignalled fence=%llu:%llu",
+ __entry->fence_context, __entry->fence_seqno,
+ __entry->ctx, __entry->seqno)
+);
+
+#endif /* _GPU_SCHED_TRACE_H_ */
+
+/* This part must be outside protection */
+#undef TRACE_INCLUDE_PATH
+#define TRACE_INCLUDE_PATH ../../drivers/gpu/drm/scheduler
+#include <trace/define_trace.h>
diff --git a/drivers/gpu/drm/scheduler/sched_entity.c b/drivers/gpu/drm/scheduler/sched_entity.c
new file mode 100644
index 000000000000..fe174a4857be
--- /dev/null
+++ b/drivers/gpu/drm/scheduler/sched_entity.c
@@ -0,0 +1,631 @@
+/*
+ * Copyright 2015 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ */
+
+#include <linux/export.h>
+#include <linux/slab.h>
+#include <linux/completion.h>
+
+#include <drm/drm_print.h>
+#include <drm/gpu_scheduler.h>
+
+#include "sched_internal.h"
+
+#include "gpu_scheduler_trace.h"
+
+/**
+ * drm_sched_entity_init - Init a context entity used by scheduler when
+ * submit to HW ring.
+ *
+ * @entity: scheduler entity to init
+ * @priority: priority of the entity
+ * @sched_list: the list of drm scheds on which jobs from this
+ * entity can be submitted
+ * @num_sched_list: number of drm sched in sched_list
+ * @guilty: atomic_t set to 1 when a job on this queue
+ * is found to be guilty causing a timeout
+ *
+ * Note that the &sched_list must have at least one element to schedule the entity.
+ *
+ * For changing @priority later on at runtime see
+ * drm_sched_entity_set_priority(). For changing the set of schedulers
+ * @sched_list at runtime see drm_sched_entity_modify_sched().
+ *
+ * An entity is cleaned up by calling drm_sched_entity_fini(). See also
+ * drm_sched_entity_destroy().
+ *
+ * Returns 0 on success or a negative error code on failure.
+ */
+int drm_sched_entity_init(struct drm_sched_entity *entity,
+ enum drm_sched_priority priority,
+ struct drm_gpu_scheduler **sched_list,
+ unsigned int num_sched_list,
+ atomic_t *guilty)
+{
+ if (!(entity && sched_list && (num_sched_list == 0 || sched_list[0])))
+ return -EINVAL;
+
+ memset(entity, 0, sizeof(struct drm_sched_entity));
+ INIT_LIST_HEAD(&entity->list);
+ entity->rq = NULL;
+ entity->guilty = guilty;
+ entity->num_sched_list = num_sched_list;
+ entity->priority = priority;
+ entity->last_user = current->group_leader;
+ /*
+ * It's perfectly valid to initialize an entity without having a valid
+ * scheduler attached. It's just not valid to use the scheduler before it
+ * is initialized itself.
+ */
+ entity->sched_list = num_sched_list > 1 ? sched_list : NULL;
+ RCU_INIT_POINTER(entity->last_scheduled, NULL);
+ RB_CLEAR_NODE(&entity->rb_tree_node);
+
+ if (num_sched_list && !sched_list[0]->sched_rq) {
+ /* Since every entry covered by num_sched_list
+ * should be non-NULL and therefore we warn drivers
+ * not to do this and to fix their DRM calling order.
+ */
+ pr_warn("%s: called with uninitialized scheduler\n", __func__);
+ } else if (num_sched_list) {
+ /* The "priority" of an entity cannot exceed the number of run-queues of a
+ * scheduler. Protect against num_rqs being 0, by converting to signed. Choose
+ * the lowest priority available.
+ */
+ if (entity->priority >= sched_list[0]->num_rqs) {
+ dev_err(sched_list[0]->dev, "entity has out-of-bounds priority: %u. num_rqs: %u\n",
+ entity->priority, sched_list[0]->num_rqs);
+ entity->priority = max_t(s32, (s32) sched_list[0]->num_rqs - 1,
+ (s32) DRM_SCHED_PRIORITY_KERNEL);
+ }
+ entity->rq = sched_list[0]->sched_rq[entity->priority];
+ }
+
+ init_completion(&entity->entity_idle);
+
+ /* We start in an idle state. */
+ complete_all(&entity->entity_idle);
+
+ spin_lock_init(&entity->lock);
+ spsc_queue_init(&entity->job_queue);
+
+ atomic_set(&entity->fence_seq, 0);
+ entity->fence_context = dma_fence_context_alloc(2);
+
+ return 0;
+}
+EXPORT_SYMBOL(drm_sched_entity_init);
+
+/**
+ * drm_sched_entity_modify_sched - Modify sched of an entity
+ * @entity: scheduler entity to init
+ * @sched_list: the list of new drm scheds which will replace
+ * existing entity->sched_list
+ * @num_sched_list: number of drm sched in sched_list
+ *
+ * Note that this must be called under the same common lock for @entity as
+ * drm_sched_job_arm() and drm_sched_entity_push_job(), or the driver needs to
+ * guarantee through some other means that this is never called while new jobs
+ * can be pushed to @entity.
+ */
+void drm_sched_entity_modify_sched(struct drm_sched_entity *entity,
+ struct drm_gpu_scheduler **sched_list,
+ unsigned int num_sched_list)
+{
+ WARN_ON(!num_sched_list || !sched_list);
+
+ spin_lock(&entity->lock);
+ entity->sched_list = sched_list;
+ entity->num_sched_list = num_sched_list;
+ spin_unlock(&entity->lock);
+}
+EXPORT_SYMBOL(drm_sched_entity_modify_sched);
+
+static bool drm_sched_entity_is_idle(struct drm_sched_entity *entity)
+{
+ rmb(); /* for list_empty to work without lock */
+
+ if (list_empty(&entity->list) ||
+ spsc_queue_count(&entity->job_queue) == 0 ||
+ entity->stopped)
+ return true;
+
+ return false;
+}
+
+/**
+ * drm_sched_entity_error - return error of last scheduled job
+ * @entity: scheduler entity to check
+ *
+ * Opportunistically return the error of the last scheduled job. Result can
+ * change any time when new jobs are pushed to the hw.
+ */
+int drm_sched_entity_error(struct drm_sched_entity *entity)
+{
+ struct dma_fence *fence;
+ int r;
+
+ rcu_read_lock();
+ fence = rcu_dereference(entity->last_scheduled);
+ r = fence ? fence->error : 0;
+ rcu_read_unlock();
+
+ return r;
+}
+EXPORT_SYMBOL(drm_sched_entity_error);
+
+static void drm_sched_entity_kill_jobs_cb(struct dma_fence *f,
+ struct dma_fence_cb *cb);
+
+static void drm_sched_entity_kill_jobs_work(struct work_struct *wrk)
+{
+ struct drm_sched_job *job = container_of(wrk, typeof(*job), work);
+ struct dma_fence *f;
+ unsigned long index;
+
+ /* Wait for all dependencies to avoid data corruptions */
+ xa_for_each(&job->dependencies, index, f) {
+ struct drm_sched_fence *s_fence = to_drm_sched_fence(f);
+
+ if (s_fence && f == &s_fence->scheduled) {
+ /* The dependencies array had a reference on the scheduled
+ * fence, and the finished fence refcount might have
+ * dropped to zero. Use dma_fence_get_rcu() so we get
+ * a NULL fence in that case.
+ */
+ f = dma_fence_get_rcu(&s_fence->finished);
+
+ /* Now that we have a reference on the finished fence,
+ * we can release the reference the dependencies array
+ * had on the scheduled fence.
+ */
+ dma_fence_put(&s_fence->scheduled);
+ }
+
+ xa_erase(&job->dependencies, index);
+ if (f && !dma_fence_add_callback(f, &job->finish_cb,
+ drm_sched_entity_kill_jobs_cb))
+ return;
+
+ dma_fence_put(f);
+ }
+
+ drm_sched_fence_scheduled(job->s_fence, NULL);
+ drm_sched_fence_finished(job->s_fence, -ESRCH);
+ WARN_ON(job->s_fence->parent);
+ job->sched->ops->free_job(job);
+}
+
+/* Signal the scheduler finished fence when the entity in question is killed. */
+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);
+
+ dma_fence_put(f);
+
+ INIT_WORK(&job->work, drm_sched_entity_kill_jobs_work);
+ schedule_work(&job->work);
+}
+
+/* Remove the entity from the scheduler and kill all pending jobs */
+static void drm_sched_entity_kill(struct drm_sched_entity *entity)
+{
+ struct drm_sched_job *job;
+ struct dma_fence *prev;
+
+ if (!entity->rq)
+ return;
+
+ spin_lock(&entity->lock);
+ entity->stopped = true;
+ drm_sched_rq_remove_entity(entity->rq, entity);
+ spin_unlock(&entity->lock);
+
+ /* Make sure this entity is not used by the scheduler at the moment */
+ wait_for_completion(&entity->entity_idle);
+
+ /* The entity is guaranteed to not be used by the scheduler */
+ prev = rcu_dereference_check(entity->last_scheduled, true);
+ dma_fence_get(prev);
+ while ((job = drm_sched_entity_queue_pop(entity))) {
+ struct drm_sched_fence *s_fence = job->s_fence;
+
+ dma_fence_get(&s_fence->finished);
+ if (!prev ||
+ dma_fence_add_callback(prev, &job->finish_cb,
+ drm_sched_entity_kill_jobs_cb)) {
+ /*
+ * Adding callback above failed.
+ * dma_fence_put() checks for NULL.
+ */
+ dma_fence_put(prev);
+ drm_sched_entity_kill_jobs_cb(NULL, &job->finish_cb);
+ }
+
+ prev = &s_fence->finished;
+ }
+ dma_fence_put(prev);
+}
+
+/**
+ * drm_sched_entity_flush - Flush a context entity
+ *
+ * @entity: scheduler entity
+ * @timeout: time to wait in for Q to become empty in jiffies.
+ *
+ * Splitting drm_sched_entity_fini() into two functions, The first one does the
+ * waiting, removes the entity from the runqueue and returns an error when the
+ * process was killed.
+ *
+ * Returns the remaining time in jiffies left from the input timeout
+ */
+long drm_sched_entity_flush(struct drm_sched_entity *entity, long timeout)
+{
+ struct drm_gpu_scheduler *sched;
+ struct task_struct *last_user;
+ long ret = timeout;
+
+ if (!entity->rq)
+ return 0;
+
+ sched = entity->rq->sched;
+ /*
+ * The client will not queue more jobs during this fini - consume
+ * existing queued ones, or discard them on SIGKILL.
+ */
+ if (current->flags & PF_EXITING) {
+ if (timeout)
+ ret = wait_event_timeout(
+ sched->job_scheduled,
+ drm_sched_entity_is_idle(entity),
+ timeout);
+ } else {
+ wait_event_killable(sched->job_scheduled,
+ drm_sched_entity_is_idle(entity));
+ }
+
+ /* For a killed process disallow further enqueueing of jobs. */
+ last_user = cmpxchg(&entity->last_user, current->group_leader, NULL);
+ if (last_user == current->group_leader &&
+ (current->flags & PF_EXITING) && (current->exit_code == SIGKILL))
+ drm_sched_entity_kill(entity);
+
+ return ret;
+}
+EXPORT_SYMBOL(drm_sched_entity_flush);
+
+/**
+ * drm_sched_entity_fini - Destroy a context entity
+ *
+ * @entity: scheduler entity
+ *
+ * Cleanups up @entity which has been initialized by drm_sched_entity_init().
+ *
+ * If there are potentially job still in flight or getting newly queued
+ * drm_sched_entity_flush() must be called first. This function then goes over
+ * the entity and signals all jobs with an error code if the process was killed.
+ */
+void drm_sched_entity_fini(struct drm_sched_entity *entity)
+{
+ /*
+ * If consumption of existing jobs wasn't completed forcefully remove
+ * them. Also makes sure that the scheduler won't touch this entity any
+ * more.
+ */
+ drm_sched_entity_kill(entity);
+
+ if (entity->dependency) {
+ dma_fence_remove_callback(entity->dependency, &entity->cb);
+ dma_fence_put(entity->dependency);
+ entity->dependency = NULL;
+ }
+
+ dma_fence_put(rcu_dereference_check(entity->last_scheduled, true));
+ RCU_INIT_POINTER(entity->last_scheduled, NULL);
+}
+EXPORT_SYMBOL(drm_sched_entity_fini);
+
+/**
+ * drm_sched_entity_destroy - Destroy a context entity
+ * @entity: scheduler entity
+ *
+ * Calls drm_sched_entity_flush() and drm_sched_entity_fini() as a
+ * convenience wrapper.
+ */
+void drm_sched_entity_destroy(struct drm_sched_entity *entity)
+{
+ drm_sched_entity_flush(entity, MAX_WAIT_SCHED_ENTITY_Q_EMPTY);
+ drm_sched_entity_fini(entity);
+}
+EXPORT_SYMBOL(drm_sched_entity_destroy);
+
+/*
+ * drm_sched_entity_wakeup - callback to clear the entity's dependency and
+ * wake up the scheduler
+ */
+static void drm_sched_entity_wakeup(struct dma_fence *f,
+ struct dma_fence_cb *cb)
+{
+ struct drm_sched_entity *entity =
+ container_of(cb, struct drm_sched_entity, cb);
+
+ entity->dependency = NULL;
+ dma_fence_put(f);
+ drm_sched_wakeup(entity->rq->sched);
+}
+
+/**
+ * drm_sched_entity_set_priority - Sets priority of the entity
+ *
+ * @entity: scheduler entity
+ * @priority: scheduler priority
+ *
+ * Update the priority of runqueues used for the entity.
+ */
+void drm_sched_entity_set_priority(struct drm_sched_entity *entity,
+ enum drm_sched_priority priority)
+{
+ spin_lock(&entity->lock);
+ entity->priority = priority;
+ spin_unlock(&entity->lock);
+}
+EXPORT_SYMBOL(drm_sched_entity_set_priority);
+
+/*
+ * Add a callback to the current dependency of the entity to wake up the
+ * scheduler when the entity becomes available.
+ */
+static bool drm_sched_entity_add_dependency_cb(struct drm_sched_entity *entity,
+ struct drm_sched_job *sched_job)
+{
+ struct drm_gpu_scheduler *sched = entity->rq->sched;
+ struct dma_fence *fence = entity->dependency;
+ struct drm_sched_fence *s_fence;
+
+ if (fence->context == entity->fence_context ||
+ fence->context == entity->fence_context + 1) {
+ /*
+ * Fence is a scheduled/finished fence from a job
+ * which belongs to the same entity, we can ignore
+ * fences from ourself
+ */
+ dma_fence_put(entity->dependency);
+ return false;
+ }
+
+ s_fence = to_drm_sched_fence(fence);
+ if (!fence->error && s_fence && s_fence->sched == sched &&
+ !test_bit(DRM_SCHED_FENCE_DONT_PIPELINE, &fence->flags)) {
+
+ /*
+ * Fence is from the same scheduler, only need to wait for
+ * it to be scheduled
+ */
+ fence = dma_fence_get(&s_fence->scheduled);
+ dma_fence_put(entity->dependency);
+ entity->dependency = fence;
+ }
+
+ if (trace_drm_sched_job_unschedulable_enabled() &&
+ !test_bit(DMA_FENCE_FLAG_SIGNALED_BIT, &entity->dependency->flags))
+ trace_drm_sched_job_unschedulable(sched_job, entity->dependency);
+
+ if (!dma_fence_add_callback(entity->dependency, &entity->cb,
+ drm_sched_entity_wakeup))
+ return true;
+
+ dma_fence_put(entity->dependency);
+ return false;
+}
+
+static struct dma_fence *
+drm_sched_job_dependency(struct drm_sched_job *job,
+ struct drm_sched_entity *entity)
+{
+ struct dma_fence *f;
+
+ /* We keep the fence around, so we can iterate over all dependencies
+ * in drm_sched_entity_kill_jobs_cb() to ensure all deps are signaled
+ * before killing the job.
+ */
+ f = xa_load(&job->dependencies, job->last_dependency);
+ if (f) {
+ job->last_dependency++;
+ return dma_fence_get(f);
+ }
+
+ if (job->sched->ops->prepare_job)
+ return job->sched->ops->prepare_job(job, entity);
+
+ return NULL;
+}
+
+struct drm_sched_job *drm_sched_entity_pop_job(struct drm_sched_entity *entity)
+{
+ struct drm_sched_job *sched_job;
+
+ sched_job = drm_sched_entity_queue_peek(entity);
+ if (!sched_job)
+ return NULL;
+
+ while ((entity->dependency =
+ drm_sched_job_dependency(sched_job, entity))) {
+ if (drm_sched_entity_add_dependency_cb(entity, sched_job))
+ return NULL;
+ }
+
+ /* skip jobs from entity that marked guilty */
+ if (entity->guilty && atomic_read(entity->guilty))
+ dma_fence_set_error(&sched_job->s_fence->finished, -ECANCELED);
+
+ dma_fence_put(rcu_dereference_check(entity->last_scheduled, true));
+ rcu_assign_pointer(entity->last_scheduled,
+ dma_fence_get(&sched_job->s_fence->finished));
+
+ /*
+ * If the queue is empty we allow drm_sched_entity_select_rq() to
+ * locklessly access ->last_scheduled. This only works if we set the
+ * pointer before we dequeue and if we a write barrier here.
+ */
+ smp_wmb();
+
+ spsc_queue_pop(&entity->job_queue);
+
+ /*
+ * Update the entity's location in the min heap according to
+ * the timestamp of the next job, if any.
+ */
+ if (drm_sched_policy == DRM_SCHED_POLICY_FIFO) {
+ struct drm_sched_job *next;
+
+ next = drm_sched_entity_queue_peek(entity);
+ if (next) {
+ struct drm_sched_rq *rq;
+
+ spin_lock(&entity->lock);
+ rq = entity->rq;
+ spin_lock(&rq->lock);
+ drm_sched_rq_update_fifo_locked(entity, rq,
+ next->submit_ts);
+ spin_unlock(&rq->lock);
+ spin_unlock(&entity->lock);
+ }
+ }
+
+ /* Jobs and entities might have different lifecycles. Since we're
+ * removing the job from the entities queue, set the jobs entity pointer
+ * to NULL to prevent any future access of the entity through this job.
+ */
+ sched_job->entity = NULL;
+
+ return sched_job;
+}
+
+void drm_sched_entity_select_rq(struct drm_sched_entity *entity)
+{
+ struct dma_fence *fence;
+ struct drm_gpu_scheduler *sched;
+ struct drm_sched_rq *rq;
+
+ /* single possible engine and already selected */
+ if (!entity->sched_list)
+ return;
+
+ /* queue non-empty, stay on the same engine */
+ if (spsc_queue_count(&entity->job_queue))
+ return;
+
+ /*
+ * Only when the queue is empty are we guaranteed that
+ * drm_sched_run_job_work() cannot change entity->last_scheduled. To
+ * enforce ordering we need a read barrier here. See
+ * drm_sched_entity_pop_job() for the other side.
+ */
+ smp_rmb();
+
+ fence = rcu_dereference_check(entity->last_scheduled, true);
+
+ /* stay on the same engine if the previous job hasn't finished */
+ if (fence && !dma_fence_is_signaled(fence))
+ return;
+
+ spin_lock(&entity->lock);
+ sched = drm_sched_pick_best(entity->sched_list, entity->num_sched_list);
+ rq = sched ? sched->sched_rq[entity->priority] : NULL;
+ if (rq != entity->rq) {
+ drm_sched_rq_remove_entity(entity->rq, entity);
+ entity->rq = rq;
+ }
+
+ if (entity->num_sched_list == 1)
+ entity->sched_list = NULL;
+
+ spin_unlock(&entity->lock);
+}
+
+/**
+ * drm_sched_entity_push_job - Submit a job to the entity's job queue
+ * @sched_job: job to submit
+ *
+ * Note: To guarantee that the order of insertion to queue matches the job's
+ * fence sequence number this function should be called with drm_sched_job_arm()
+ * under common lock for the struct drm_sched_entity that was set up for
+ * @sched_job in drm_sched_job_init().
+ */
+void drm_sched_entity_push_job(struct drm_sched_job *sched_job)
+{
+ struct drm_sched_entity *entity = sched_job->entity;
+ bool first;
+ ktime_t submit_ts;
+
+ trace_drm_sched_job_queue(sched_job, entity);
+
+ if (trace_drm_sched_job_add_dep_enabled()) {
+ struct dma_fence *entry;
+ unsigned long index;
+
+ xa_for_each(&sched_job->dependencies, index, entry)
+ trace_drm_sched_job_add_dep(sched_job, entry);
+ }
+ atomic_inc(entity->rq->sched->score);
+ WRITE_ONCE(entity->last_user, current->group_leader);
+
+ /*
+ * After the sched_job is pushed into the entity queue, it may be
+ * completed and freed up at any time. We can no longer access it.
+ * Make sure to set the submit_ts first, to avoid a race.
+ */
+ sched_job->submit_ts = submit_ts = ktime_get();
+ first = spsc_queue_push(&entity->job_queue, &sched_job->queue_node);
+
+ /* first job wakes up scheduler */
+ if (first) {
+ struct drm_gpu_scheduler *sched;
+ struct drm_sched_rq *rq;
+
+ /* Add the entity to the run queue */
+ spin_lock(&entity->lock);
+ if (entity->stopped) {
+ spin_unlock(&entity->lock);
+
+ DRM_ERROR("Trying to push to a killed entity\n");
+ return;
+ }
+
+ rq = entity->rq;
+ sched = rq->sched;
+
+ spin_lock(&rq->lock);
+ drm_sched_rq_add_entity(rq, entity);
+
+ if (drm_sched_policy == DRM_SCHED_POLICY_FIFO)
+ drm_sched_rq_update_fifo_locked(entity, rq, submit_ts);
+
+ spin_unlock(&rq->lock);
+ spin_unlock(&entity->lock);
+
+ drm_sched_wakeup(sched);
+ }
+}
+EXPORT_SYMBOL(drm_sched_entity_push_job);
diff --git a/drivers/gpu/drm/scheduler/sched_fence.c b/drivers/gpu/drm/scheduler/sched_fence.c
new file mode 100644
index 000000000000..9391d6f0dc01
--- /dev/null
+++ b/drivers/gpu/drm/scheduler/sched_fence.c
@@ -0,0 +1,242 @@
+/*
+ * Copyright 2015 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ */
+
+#include <linux/export.h>
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/wait.h>
+
+#include <drm/gpu_scheduler.h>
+
+#include "sched_internal.h"
+
+static struct kmem_cache *sched_fence_slab;
+
+static int __init drm_sched_fence_slab_init(void)
+{
+ sched_fence_slab = KMEM_CACHE(drm_sched_fence, SLAB_HWCACHE_ALIGN);
+ if (!sched_fence_slab)
+ return -ENOMEM;
+
+ return 0;
+}
+
+static void __exit drm_sched_fence_slab_fini(void)
+{
+ rcu_barrier();
+ kmem_cache_destroy(sched_fence_slab);
+}
+
+static void drm_sched_fence_set_parent(struct drm_sched_fence *s_fence,
+ struct dma_fence *fence)
+{
+ /*
+ * smp_store_release() to ensure another thread racing us
+ * in drm_sched_fence_set_deadline_finished() sees the
+ * fence's parent set before test_bit()
+ */
+ smp_store_release(&s_fence->parent, dma_fence_get(fence));
+ if (test_bit(DRM_SCHED_FENCE_FLAG_HAS_DEADLINE_BIT,
+ &s_fence->finished.flags))
+ dma_fence_set_deadline(fence, s_fence->deadline);
+}
+
+void drm_sched_fence_scheduled(struct drm_sched_fence *fence,
+ struct dma_fence *parent)
+{
+ /* Set the parent before signaling the scheduled fence, such that,
+ * any waiter expecting the parent to be filled after the job has
+ * been scheduled (which is the case for drivers delegating waits
+ * to some firmware) doesn't have to busy wait for parent to show
+ * up.
+ */
+ if (!IS_ERR_OR_NULL(parent))
+ drm_sched_fence_set_parent(fence, parent);
+
+ dma_fence_signal(&fence->scheduled);
+}
+
+void drm_sched_fence_finished(struct drm_sched_fence *fence, int result)
+{
+ if (result)
+ dma_fence_set_error(&fence->finished, result);
+ dma_fence_signal(&fence->finished);
+}
+
+static const char *drm_sched_fence_get_driver_name(struct dma_fence *fence)
+{
+ return "drm_sched";
+}
+
+static const char *drm_sched_fence_get_timeline_name(struct dma_fence *f)
+{
+ struct drm_sched_fence *fence = to_drm_sched_fence(f);
+ return (const char *)fence->sched->name;
+}
+
+static void drm_sched_fence_free_rcu(struct rcu_head *rcu)
+{
+ struct dma_fence *f = container_of(rcu, struct dma_fence, rcu);
+ struct drm_sched_fence *fence = to_drm_sched_fence(f);
+
+ if (!WARN_ON_ONCE(!fence))
+ kmem_cache_free(sched_fence_slab, fence);
+}
+
+/**
+ * drm_sched_fence_free - free up an uninitialized fence
+ *
+ * @fence: fence to free
+ *
+ * Free up the fence memory. Should only be used if drm_sched_fence_init()
+ * has not been called yet.
+ */
+void drm_sched_fence_free(struct drm_sched_fence *fence)
+{
+ /* This function should not be called if the fence has been initialized. */
+ if (!WARN_ON_ONCE(fence->sched))
+ kmem_cache_free(sched_fence_slab, fence);
+}
+
+/**
+ * drm_sched_fence_release_scheduled - callback that fence can be freed
+ *
+ * @f: fence
+ *
+ * This function is called when the reference count becomes zero.
+ * It just RCU schedules freeing up the fence.
+ */
+static void drm_sched_fence_release_scheduled(struct dma_fence *f)
+{
+ struct drm_sched_fence *fence = to_drm_sched_fence(f);
+
+ dma_fence_put(fence->parent);
+ call_rcu(&fence->finished.rcu, drm_sched_fence_free_rcu);
+}
+
+/**
+ * drm_sched_fence_release_finished - drop extra reference
+ *
+ * @f: fence
+ *
+ * Drop the extra reference from the scheduled fence to the base fence.
+ */
+static void drm_sched_fence_release_finished(struct dma_fence *f)
+{
+ struct drm_sched_fence *fence = to_drm_sched_fence(f);
+
+ dma_fence_put(&fence->scheduled);
+}
+
+static void drm_sched_fence_set_deadline_finished(struct dma_fence *f,
+ ktime_t deadline)
+{
+ struct drm_sched_fence *fence = to_drm_sched_fence(f);
+ struct dma_fence *parent;
+ unsigned long flags;
+
+ spin_lock_irqsave(&fence->lock, flags);
+
+ /* If we already have an earlier deadline, keep it: */
+ if (test_bit(DRM_SCHED_FENCE_FLAG_HAS_DEADLINE_BIT, &f->flags) &&
+ ktime_before(fence->deadline, deadline)) {
+ spin_unlock_irqrestore(&fence->lock, flags);
+ return;
+ }
+
+ fence->deadline = deadline;
+ set_bit(DRM_SCHED_FENCE_FLAG_HAS_DEADLINE_BIT, &f->flags);
+
+ spin_unlock_irqrestore(&fence->lock, flags);
+
+ /*
+ * smp_load_aquire() to ensure that if we are racing another
+ * thread calling drm_sched_fence_set_parent(), that we see
+ * the parent set before it calls test_bit(HAS_DEADLINE_BIT)
+ */
+ parent = smp_load_acquire(&fence->parent);
+ if (parent)
+ dma_fence_set_deadline(parent, deadline);
+}
+
+static const struct dma_fence_ops drm_sched_fence_ops_scheduled = {
+ .get_driver_name = drm_sched_fence_get_driver_name,
+ .get_timeline_name = drm_sched_fence_get_timeline_name,
+ .release = drm_sched_fence_release_scheduled,
+};
+
+static const struct dma_fence_ops drm_sched_fence_ops_finished = {
+ .get_driver_name = drm_sched_fence_get_driver_name,
+ .get_timeline_name = drm_sched_fence_get_timeline_name,
+ .release = drm_sched_fence_release_finished,
+ .set_deadline = drm_sched_fence_set_deadline_finished,
+};
+
+struct drm_sched_fence *to_drm_sched_fence(struct dma_fence *f)
+{
+ if (f->ops == &drm_sched_fence_ops_scheduled)
+ return container_of(f, struct drm_sched_fence, scheduled);
+
+ if (f->ops == &drm_sched_fence_ops_finished)
+ return container_of(f, struct drm_sched_fence, finished);
+
+ return NULL;
+}
+EXPORT_SYMBOL(to_drm_sched_fence);
+
+struct drm_sched_fence *drm_sched_fence_alloc(struct drm_sched_entity *entity,
+ void *owner,
+ u64 drm_client_id)
+{
+ struct drm_sched_fence *fence = NULL;
+
+ fence = kmem_cache_zalloc(sched_fence_slab, GFP_KERNEL);
+ if (fence == NULL)
+ return NULL;
+
+ fence->owner = owner;
+ fence->drm_client_id = drm_client_id;
+ spin_lock_init(&fence->lock);
+
+ return fence;
+}
+
+void drm_sched_fence_init(struct drm_sched_fence *fence,
+ struct drm_sched_entity *entity)
+{
+ unsigned seq;
+
+ fence->sched = entity->rq->sched;
+ seq = atomic_inc_return(&entity->fence_seq);
+ dma_fence_init(&fence->scheduled, &drm_sched_fence_ops_scheduled,
+ &fence->lock, entity->fence_context, seq);
+ dma_fence_init(&fence->finished, &drm_sched_fence_ops_finished,
+ &fence->lock, entity->fence_context + 1, seq);
+}
+
+module_init(drm_sched_fence_slab_init);
+module_exit(drm_sched_fence_slab_fini);
+
+MODULE_DESCRIPTION("DRM GPU scheduler");
+MODULE_LICENSE("GPL and additional rights");
diff --git a/drivers/gpu/drm/scheduler/sched_internal.h b/drivers/gpu/drm/scheduler/sched_internal.h
new file mode 100644
index 000000000000..7ea5a6736f98
--- /dev/null
+++ b/drivers/gpu/drm/scheduler/sched_internal.h
@@ -0,0 +1,91 @@
+/* SPDX-License-Identifier: MIT */
+
+#ifndef _DRM_GPU_SCHEDULER_INTERNAL_H_
+#define _DRM_GPU_SCHEDULER_INTERNAL_H_
+
+
+/* Used to choose between FIFO and RR job-scheduling */
+extern int drm_sched_policy;
+
+#define DRM_SCHED_POLICY_RR 0
+#define DRM_SCHED_POLICY_FIFO 1
+
+void drm_sched_wakeup(struct drm_gpu_scheduler *sched);
+
+void drm_sched_rq_add_entity(struct drm_sched_rq *rq,
+ struct drm_sched_entity *entity);
+void drm_sched_rq_remove_entity(struct drm_sched_rq *rq,
+ struct drm_sched_entity *entity);
+
+void drm_sched_rq_update_fifo_locked(struct drm_sched_entity *entity,
+ struct drm_sched_rq *rq, ktime_t ts);
+
+void drm_sched_entity_select_rq(struct drm_sched_entity *entity);
+struct drm_sched_job *drm_sched_entity_pop_job(struct drm_sched_entity *entity);
+
+struct drm_sched_fence *drm_sched_fence_alloc(struct drm_sched_entity *s_entity,
+ void *owner, u64 drm_client_id);
+void drm_sched_fence_init(struct drm_sched_fence *fence,
+ struct drm_sched_entity *entity);
+void drm_sched_fence_free(struct drm_sched_fence *fence);
+
+void drm_sched_fence_scheduled(struct drm_sched_fence *fence,
+ struct dma_fence *parent);
+void drm_sched_fence_finished(struct drm_sched_fence *fence, int result);
+
+/**
+ * drm_sched_entity_queue_pop - Low level helper for popping queued jobs
+ *
+ * @entity: scheduler entity
+ *
+ * Low level helper for popping queued jobs.
+ *
+ * Returns: The job dequeued or NULL.
+ */
+static inline struct drm_sched_job *
+drm_sched_entity_queue_pop(struct drm_sched_entity *entity)
+{
+ struct spsc_node *node;
+
+ node = spsc_queue_pop(&entity->job_queue);
+ if (!node)
+ return NULL;
+
+ return container_of(node, struct drm_sched_job, queue_node);
+}
+
+/**
+ * drm_sched_entity_queue_peek - Low level helper for peeking at the job queue
+ *
+ * @entity: scheduler entity
+ *
+ * Low level helper for peeking at the job queue
+ *
+ * Returns: The job at the head of the queue or NULL.
+ */
+static inline struct drm_sched_job *
+drm_sched_entity_queue_peek(struct drm_sched_entity *entity)
+{
+ struct spsc_node *node;
+
+ node = spsc_queue_peek(&entity->job_queue);
+ if (!node)
+ return NULL;
+
+ return container_of(node, struct drm_sched_job, queue_node);
+}
+
+/* Return true if entity could provide a job. */
+static inline bool
+drm_sched_entity_is_ready(struct drm_sched_entity *entity)
+{
+ if (!spsc_queue_count(&entity->job_queue))
+ return false;
+
+ if (READ_ONCE(entity->dependency))
+ return false;
+
+ return true;
+}
+
+#endif
diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c
new file mode 100644
index 000000000000..1d4f1b822e7b
--- /dev/null
+++ b/drivers/gpu/drm/scheduler/sched_main.c
@@ -0,0 +1,1569 @@
+/*
+ * Copyright 2015 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ */
+
+/**
+ * DOC: Overview
+ *
+ * The GPU scheduler provides entities which allow userspace to push jobs
+ * into software queues which are then scheduled on a hardware run queue.
+ * The software queues have a priority among them. The scheduler selects the entities
+ * from the run queue using a FIFO. The scheduler provides dependency handling
+ * features among jobs. The driver is supposed to provide callback functions for
+ * backend operations to the scheduler like submitting a job to hardware run queue,
+ * returning the dependencies of a job etc.
+ *
+ * The organisation of the scheduler is the following:
+ *
+ * 1. Each hw run queue has one scheduler
+ * 2. Each scheduler has multiple run queues with different priorities
+ * (e.g., HIGH_HW,HIGH_SW, KERNEL, NORMAL)
+ * 3. Each scheduler run queue has a queue of entities to schedule
+ * 4. Entities themselves maintain a queue of jobs that will be scheduled on
+ * the hardware.
+ *
+ * The jobs in an entity are always scheduled in the order in which they were pushed.
+ *
+ * Note that once a job was taken from the entities queue and pushed to the
+ * hardware, i.e. the pending queue, the entity must not be referenced anymore
+ * through the jobs entity pointer.
+ */
+
+/**
+ * DOC: Flow Control
+ *
+ * The DRM GPU scheduler provides a flow control mechanism to regulate the rate
+ * in which the jobs fetched from scheduler entities are executed.
+ *
+ * In this context the &drm_gpu_scheduler keeps track of a driver specified
+ * credit limit representing the capacity of this scheduler and a credit count;
+ * every &drm_sched_job carries a driver specified number of credits.
+ *
+ * Once a job is executed (but not yet finished), the job's credits contribute
+ * to the scheduler's credit count until the job is finished. If by executing
+ * one more job the scheduler's credit count would exceed the scheduler's
+ * credit limit, the job won't be executed. Instead, the scheduler will wait
+ * until the credit count has decreased enough to not overflow its credit limit.
+ * This implies waiting for previously executed jobs.
+ */
+
+#include <linux/export.h>
+#include <linux/wait.h>
+#include <linux/sched.h>
+#include <linux/completion.h>
+#include <linux/dma-resv.h>
+#include <uapi/linux/sched/types.h>
+
+#include <drm/drm_print.h>
+#include <drm/drm_gem.h>
+#include <drm/drm_syncobj.h>
+#include <drm/gpu_scheduler.h>
+#include <drm/spsc_queue.h>
+
+#include "sched_internal.h"
+
+#define CREATE_TRACE_POINTS
+#include "gpu_scheduler_trace.h"
+
+int drm_sched_policy = DRM_SCHED_POLICY_FIFO;
+
+/**
+ * DOC: sched_policy (int)
+ * Used to override default entities scheduling policy in a run queue.
+ */
+MODULE_PARM_DESC(sched_policy, "Specify the scheduling policy for entities on a run-queue, " __stringify(DRM_SCHED_POLICY_RR) " = Round Robin, " __stringify(DRM_SCHED_POLICY_FIFO) " = FIFO (default).");
+module_param_named(sched_policy, drm_sched_policy, int, 0444);
+
+static u32 drm_sched_available_credits(struct drm_gpu_scheduler *sched)
+{
+ u32 credits;
+
+ WARN_ON(check_sub_overflow(sched->credit_limit,
+ atomic_read(&sched->credit_count),
+ &credits));
+
+ return credits;
+}
+
+/**
+ * drm_sched_can_queue -- Can we queue more to the hardware?
+ * @sched: scheduler instance
+ * @entity: the scheduler entity
+ *
+ * Return true if we can push at least one more job from @entity, false
+ * otherwise.
+ */
+static bool drm_sched_can_queue(struct drm_gpu_scheduler *sched,
+ struct drm_sched_entity *entity)
+{
+ struct drm_sched_job *s_job;
+
+ s_job = drm_sched_entity_queue_peek(entity);
+ if (!s_job)
+ return false;
+
+ /* If a job exceeds the credit limit, truncate it to the credit limit
+ * itself to guarantee forward progress.
+ */
+ if (s_job->credits > sched->credit_limit) {
+ dev_WARN(sched->dev,
+ "Jobs may not exceed the credit limit, truncate.\n");
+ s_job->credits = sched->credit_limit;
+ }
+
+ return drm_sched_available_credits(sched) >= s_job->credits;
+}
+
+static __always_inline bool drm_sched_entity_compare_before(struct rb_node *a,
+ const struct rb_node *b)
+{
+ struct drm_sched_entity *ent_a = rb_entry((a), struct drm_sched_entity, rb_tree_node);
+ struct drm_sched_entity *ent_b = rb_entry((b), struct drm_sched_entity, rb_tree_node);
+
+ return ktime_before(ent_a->oldest_job_waiting, ent_b->oldest_job_waiting);
+}
+
+static void drm_sched_rq_remove_fifo_locked(struct drm_sched_entity *entity,
+ struct drm_sched_rq *rq)
+{
+ if (!RB_EMPTY_NODE(&entity->rb_tree_node)) {
+ rb_erase_cached(&entity->rb_tree_node, &rq->rb_tree_root);
+ RB_CLEAR_NODE(&entity->rb_tree_node);
+ }
+}
+
+void drm_sched_rq_update_fifo_locked(struct drm_sched_entity *entity,
+ struct drm_sched_rq *rq,
+ ktime_t ts)
+{
+ /*
+ * Both locks need to be grabbed, one to protect from entity->rq change
+ * for entity from within concurrent drm_sched_entity_select_rq and the
+ * other to update the rb tree structure.
+ */
+ lockdep_assert_held(&entity->lock);
+ lockdep_assert_held(&rq->lock);
+
+ drm_sched_rq_remove_fifo_locked(entity, rq);
+
+ entity->oldest_job_waiting = ts;
+
+ rb_add_cached(&entity->rb_tree_node, &rq->rb_tree_root,
+ drm_sched_entity_compare_before);
+}
+
+/**
+ * drm_sched_rq_init - initialize a given run queue struct
+ *
+ * @sched: scheduler instance to associate with this run queue
+ * @rq: scheduler run queue
+ *
+ * Initializes a scheduler runqueue.
+ */
+static void drm_sched_rq_init(struct drm_gpu_scheduler *sched,
+ struct drm_sched_rq *rq)
+{
+ spin_lock_init(&rq->lock);
+ INIT_LIST_HEAD(&rq->entities);
+ rq->rb_tree_root = RB_ROOT_CACHED;
+ rq->current_entity = NULL;
+ rq->sched = sched;
+}
+
+/**
+ * drm_sched_rq_add_entity - add an entity
+ *
+ * @rq: scheduler run queue
+ * @entity: scheduler entity
+ *
+ * Adds a scheduler entity to the run queue.
+ */
+void drm_sched_rq_add_entity(struct drm_sched_rq *rq,
+ struct drm_sched_entity *entity)
+{
+ lockdep_assert_held(&entity->lock);
+ lockdep_assert_held(&rq->lock);
+
+ if (!list_empty(&entity->list))
+ return;
+
+ atomic_inc(rq->sched->score);
+ list_add_tail(&entity->list, &rq->entities);
+}
+
+/**
+ * drm_sched_rq_remove_entity - remove an entity
+ *
+ * @rq: scheduler run queue
+ * @entity: scheduler entity
+ *
+ * Removes a scheduler entity from the run queue.
+ */
+void drm_sched_rq_remove_entity(struct drm_sched_rq *rq,
+ struct drm_sched_entity *entity)
+{
+ lockdep_assert_held(&entity->lock);
+
+ if (list_empty(&entity->list))
+ return;
+
+ spin_lock(&rq->lock);
+
+ atomic_dec(rq->sched->score);
+ list_del_init(&entity->list);
+
+ if (rq->current_entity == entity)
+ rq->current_entity = NULL;
+
+ if (drm_sched_policy == DRM_SCHED_POLICY_FIFO)
+ drm_sched_rq_remove_fifo_locked(entity, rq);
+
+ spin_unlock(&rq->lock);
+}
+
+/**
+ * drm_sched_rq_select_entity_rr - Select an entity which could provide a job to run
+ *
+ * @sched: the gpu scheduler
+ * @rq: scheduler run queue to check.
+ *
+ * Try to find the next ready entity.
+ *
+ * Return an entity if one is found; return an error-pointer (!NULL) if an
+ * entity was ready, but the scheduler had insufficient credits to accommodate
+ * its job; return NULL, if no ready entity was found.
+ */
+static struct drm_sched_entity *
+drm_sched_rq_select_entity_rr(struct drm_gpu_scheduler *sched,
+ struct drm_sched_rq *rq)
+{
+ struct drm_sched_entity *entity;
+
+ spin_lock(&rq->lock);
+
+ entity = rq->current_entity;
+ if (entity) {
+ list_for_each_entry_continue(entity, &rq->entities, list) {
+ if (drm_sched_entity_is_ready(entity))
+ goto found;
+ }
+ }
+
+ list_for_each_entry(entity, &rq->entities, list) {
+ if (drm_sched_entity_is_ready(entity))
+ goto found;
+
+ if (entity == rq->current_entity)
+ break;
+ }
+
+ spin_unlock(&rq->lock);
+
+ return NULL;
+
+found:
+ if (!drm_sched_can_queue(sched, entity)) {
+ /*
+ * If scheduler cannot take more jobs signal the caller to not
+ * consider lower priority queues.
+ */
+ entity = ERR_PTR(-ENOSPC);
+ } else {
+ rq->current_entity = entity;
+ reinit_completion(&entity->entity_idle);
+ }
+
+ spin_unlock(&rq->lock);
+
+ return entity;
+}
+
+/**
+ * drm_sched_rq_select_entity_fifo - Select an entity which provides a job to run
+ *
+ * @sched: the gpu scheduler
+ * @rq: scheduler run queue to check.
+ *
+ * Find oldest waiting ready entity.
+ *
+ * Return an entity if one is found; return an error-pointer (!NULL) if an
+ * entity was ready, but the scheduler had insufficient credits to accommodate
+ * its job; return NULL, if no ready entity was found.
+ */
+static struct drm_sched_entity *
+drm_sched_rq_select_entity_fifo(struct drm_gpu_scheduler *sched,
+ struct drm_sched_rq *rq)
+{
+ struct rb_node *rb;
+
+ spin_lock(&rq->lock);
+ for (rb = rb_first_cached(&rq->rb_tree_root); rb; rb = rb_next(rb)) {
+ struct drm_sched_entity *entity;
+
+ entity = rb_entry(rb, struct drm_sched_entity, rb_tree_node);
+ if (drm_sched_entity_is_ready(entity)) {
+ /* If we can't queue yet, preserve the current entity in
+ * terms of fairness.
+ */
+ if (!drm_sched_can_queue(sched, entity)) {
+ spin_unlock(&rq->lock);
+ return ERR_PTR(-ENOSPC);
+ }
+
+ reinit_completion(&entity->entity_idle);
+ break;
+ }
+ }
+ spin_unlock(&rq->lock);
+
+ return rb ? rb_entry(rb, struct drm_sched_entity, rb_tree_node) : NULL;
+}
+
+/**
+ * drm_sched_run_job_queue - enqueue run-job work
+ * @sched: scheduler instance
+ */
+static void drm_sched_run_job_queue(struct drm_gpu_scheduler *sched)
+{
+ if (!READ_ONCE(sched->pause_submit))
+ queue_work(sched->submit_wq, &sched->work_run_job);
+}
+
+/**
+ * drm_sched_run_free_queue - enqueue free-job work
+ * @sched: scheduler instance
+ */
+static void drm_sched_run_free_queue(struct drm_gpu_scheduler *sched)
+{
+ if (!READ_ONCE(sched->pause_submit))
+ queue_work(sched->submit_wq, &sched->work_free_job);
+}
+
+/**
+ * drm_sched_job_done - complete a job
+ * @s_job: pointer to the job which is done
+ *
+ * Finish the job's fence and resubmit the work items.
+ */
+static void drm_sched_job_done(struct drm_sched_job *s_job, int result)
+{
+ struct drm_sched_fence *s_fence = s_job->s_fence;
+ struct drm_gpu_scheduler *sched = s_fence->sched;
+
+ atomic_sub(s_job->credits, &sched->credit_count);
+ atomic_dec(sched->score);
+
+ trace_drm_sched_job_done(s_fence);
+
+ dma_fence_get(&s_fence->finished);
+ drm_sched_fence_finished(s_fence, result);
+ dma_fence_put(&s_fence->finished);
+ drm_sched_run_free_queue(sched);
+}
+
+/**
+ * drm_sched_job_done_cb - the callback for a done job
+ * @f: fence
+ * @cb: fence callbacks
+ */
+static void drm_sched_job_done_cb(struct dma_fence *f, struct dma_fence_cb *cb)
+{
+ struct drm_sched_job *s_job = container_of(cb, struct drm_sched_job, cb);
+
+ drm_sched_job_done(s_job, f->error);
+}
+
+/**
+ * drm_sched_start_timeout - start timeout for reset worker
+ *
+ * @sched: scheduler instance to start the worker for
+ *
+ * Start the timeout for the given scheduler.
+ */
+static void drm_sched_start_timeout(struct drm_gpu_scheduler *sched)
+{
+ lockdep_assert_held(&sched->job_list_lock);
+
+ if (sched->timeout != MAX_SCHEDULE_TIMEOUT &&
+ !list_empty(&sched->pending_list))
+ mod_delayed_work(sched->timeout_wq, &sched->work_tdr, sched->timeout);
+}
+
+static void drm_sched_start_timeout_unlocked(struct drm_gpu_scheduler *sched)
+{
+ spin_lock(&sched->job_list_lock);
+ drm_sched_start_timeout(sched);
+ spin_unlock(&sched->job_list_lock);
+}
+
+/**
+ * drm_sched_tdr_queue_imm: - immediately start job timeout handler
+ *
+ * @sched: scheduler for which the timeout handling should be started.
+ *
+ * Start timeout handling immediately for the named scheduler.
+ */
+void drm_sched_tdr_queue_imm(struct drm_gpu_scheduler *sched)
+{
+ spin_lock(&sched->job_list_lock);
+ sched->timeout = 0;
+ drm_sched_start_timeout(sched);
+ spin_unlock(&sched->job_list_lock);
+}
+EXPORT_SYMBOL(drm_sched_tdr_queue_imm);
+
+/**
+ * drm_sched_fault - immediately start timeout handler
+ *
+ * @sched: scheduler where the timeout handling should be started.
+ *
+ * Start timeout handling immediately when the driver detects a hardware fault.
+ */
+void drm_sched_fault(struct drm_gpu_scheduler *sched)
+{
+ if (sched->timeout_wq)
+ mod_delayed_work(sched->timeout_wq, &sched->work_tdr, 0);
+}
+EXPORT_SYMBOL(drm_sched_fault);
+
+/**
+ * drm_sched_suspend_timeout - Suspend scheduler job timeout
+ *
+ * @sched: scheduler instance for which to suspend the timeout
+ *
+ * Suspend the delayed work timeout for the scheduler. This is done by
+ * modifying the delayed work timeout to an arbitrary large value,
+ * MAX_SCHEDULE_TIMEOUT in this case.
+ *
+ * Returns the timeout remaining
+ *
+ */
+unsigned long drm_sched_suspend_timeout(struct drm_gpu_scheduler *sched)
+{
+ unsigned long sched_timeout, now = jiffies;
+
+ sched_timeout = sched->work_tdr.timer.expires;
+
+ /*
+ * Modify the timeout to an arbitrarily large value. This also prevents
+ * the timeout to be restarted when new submissions arrive
+ */
+ if (mod_delayed_work(sched->timeout_wq, &sched->work_tdr, MAX_SCHEDULE_TIMEOUT)
+ && time_after(sched_timeout, now))
+ return sched_timeout - now;
+ else
+ return sched->timeout;
+}
+EXPORT_SYMBOL(drm_sched_suspend_timeout);
+
+/**
+ * drm_sched_resume_timeout - Resume scheduler job timeout
+ *
+ * @sched: scheduler instance for which to resume the timeout
+ * @remaining: remaining timeout
+ *
+ * Resume the delayed work timeout for the scheduler.
+ */
+void drm_sched_resume_timeout(struct drm_gpu_scheduler *sched,
+ unsigned long remaining)
+{
+ spin_lock(&sched->job_list_lock);
+
+ if (list_empty(&sched->pending_list))
+ cancel_delayed_work(&sched->work_tdr);
+ else
+ mod_delayed_work(sched->timeout_wq, &sched->work_tdr, remaining);
+
+ spin_unlock(&sched->job_list_lock);
+}
+EXPORT_SYMBOL(drm_sched_resume_timeout);
+
+static void drm_sched_job_begin(struct drm_sched_job *s_job)
+{
+ struct drm_gpu_scheduler *sched = s_job->sched;
+
+ spin_lock(&sched->job_list_lock);
+ list_add_tail(&s_job->list, &sched->pending_list);
+ drm_sched_start_timeout(sched);
+ spin_unlock(&sched->job_list_lock);
+}
+
+/**
+ * drm_sched_job_reinsert_on_false_timeout - reinsert the job on a false timeout
+ * @sched: scheduler instance
+ * @job: job to be reinserted on the pending list
+ *
+ * In the case of a "false timeout" - when a timeout occurs but the GPU isn't
+ * hung and is making progress, the scheduler must reinsert the job back into
+ * @sched->pending_list. Otherwise, the job and its resources won't be freed
+ * through the &struct drm_sched_backend_ops.free_job callback.
+ *
+ * This function must be used in "false timeout" cases only.
+ */
+static void drm_sched_job_reinsert_on_false_timeout(struct drm_gpu_scheduler *sched,
+ struct drm_sched_job *job)
+{
+ spin_lock(&sched->job_list_lock);
+ list_add(&job->list, &sched->pending_list);
+
+ /* After reinserting the job, the scheduler enqueues the free-job work
+ * again if ready. Otherwise, a signaled job could be added to the
+ * pending list, but never freed.
+ */
+ drm_sched_run_free_queue(sched);
+ spin_unlock(&sched->job_list_lock);
+}
+
+static void drm_sched_job_timedout(struct work_struct *work)
+{
+ struct drm_gpu_scheduler *sched;
+ struct drm_sched_job *job;
+ enum drm_gpu_sched_stat status = DRM_GPU_SCHED_STAT_RESET;
+
+ sched = container_of(work, struct drm_gpu_scheduler, work_tdr.work);
+
+ /* Protects against concurrent deletion in drm_sched_get_finished_job */
+ spin_lock(&sched->job_list_lock);
+ job = list_first_entry_or_null(&sched->pending_list,
+ struct drm_sched_job, list);
+
+ if (job) {
+ /*
+ * Remove the bad job so it cannot be freed by a concurrent
+ * &struct drm_sched_backend_ops.free_job. It will be
+ * reinserted after the scheduler's work items have been
+ * cancelled, at which point it's safe.
+ */
+ list_del_init(&job->list);
+ spin_unlock(&sched->job_list_lock);
+
+ status = job->sched->ops->timedout_job(job);
+
+ /*
+ * Guilty job did complete and hence needs to be manually removed
+ * See drm_sched_stop doc.
+ */
+ if (sched->free_guilty) {
+ job->sched->ops->free_job(job);
+ sched->free_guilty = false;
+ }
+
+ if (status == DRM_GPU_SCHED_STAT_NO_HANG)
+ drm_sched_job_reinsert_on_false_timeout(sched, job);
+ } else {
+ spin_unlock(&sched->job_list_lock);
+ }
+
+ if (status != DRM_GPU_SCHED_STAT_ENODEV)
+ drm_sched_start_timeout_unlocked(sched);
+}
+
+/**
+ * drm_sched_stop - stop the scheduler
+ *
+ * @sched: scheduler instance
+ * @bad: job which caused the time out
+ *
+ * Stop the scheduler and also removes and frees all completed jobs.
+ * Note: bad job will not be freed as it might be used later and so it's
+ * callers responsibility to release it manually if it's not part of the
+ * pending list any more.
+ *
+ * This function is typically used for reset recovery (see the docu of
+ * drm_sched_backend_ops.timedout_job() for details). Do not call it for
+ * scheduler teardown, i.e., before calling drm_sched_fini().
+ *
+ * As it's only used for reset recovery, drivers must not call this function
+ * in their &struct drm_sched_backend_ops.timedout_job callback when they
+ * skip a reset using &enum drm_gpu_sched_stat.DRM_GPU_SCHED_STAT_NO_HANG.
+ */
+void drm_sched_stop(struct drm_gpu_scheduler *sched, struct drm_sched_job *bad)
+{
+ struct drm_sched_job *s_job, *tmp;
+
+ drm_sched_wqueue_stop(sched);
+
+ /*
+ * Reinsert back the bad job here - now it's safe as
+ * drm_sched_get_finished_job() cannot race against us and release the
+ * bad job at this point - we parked (waited for) any in progress
+ * (earlier) cleanups and drm_sched_get_finished_job() will not be
+ * called now until the scheduler's work items are submitted again.
+ */
+ if (bad && bad->sched == sched)
+ /*
+ * Add at the head of the queue to reflect it was the earliest
+ * job extracted.
+ */
+ list_add(&bad->list, &sched->pending_list);
+
+ /*
+ * Iterate the job list from later to earlier one and either deactive
+ * their HW callbacks or remove them from pending list if they already
+ * signaled.
+ * This iteration is thread safe as the scheduler's work items have been
+ * cancelled.
+ */
+ list_for_each_entry_safe_reverse(s_job, tmp, &sched->pending_list,
+ list) {
+ if (s_job->s_fence->parent &&
+ dma_fence_remove_callback(s_job->s_fence->parent,
+ &s_job->cb)) {
+ dma_fence_put(s_job->s_fence->parent);
+ s_job->s_fence->parent = NULL;
+ atomic_sub(s_job->credits, &sched->credit_count);
+ } else {
+ /*
+ * remove job from pending_list.
+ * Locking here is for concurrent resume timeout
+ */
+ spin_lock(&sched->job_list_lock);
+ list_del_init(&s_job->list);
+ spin_unlock(&sched->job_list_lock);
+
+ /*
+ * Wait for job's HW fence callback to finish using s_job
+ * before releasing it.
+ *
+ * Job is still alive so fence refcount at least 1
+ */
+ dma_fence_wait(&s_job->s_fence->finished, false);
+
+ /*
+ * We must keep bad job alive for later use during
+ * recovery by some of the drivers but leave a hint
+ * that the guilty job must be released.
+ */
+ if (bad != s_job)
+ sched->ops->free_job(s_job);
+ else
+ sched->free_guilty = true;
+ }
+ }
+
+ /*
+ * Stop pending timer in flight as we rearm it in drm_sched_start. This
+ * avoids the pending timeout work in progress to fire right away after
+ * this TDR finished and before the newly restarted jobs had a
+ * chance to complete.
+ */
+ cancel_delayed_work(&sched->work_tdr);
+}
+EXPORT_SYMBOL(drm_sched_stop);
+
+/**
+ * drm_sched_start - recover jobs after a reset
+ *
+ * @sched: scheduler instance
+ * @errno: error to set on the pending fences
+ *
+ * This function is typically used for reset recovery (see the docu of
+ * drm_sched_backend_ops.timedout_job() for details). Do not call it for
+ * scheduler startup. The scheduler itself is fully operational after
+ * drm_sched_init() succeeded.
+ *
+ * As it's only used for reset recovery, drivers must not call this function
+ * in their &struct drm_sched_backend_ops.timedout_job callback when they
+ * skip a reset using &enum drm_gpu_sched_stat.DRM_GPU_SCHED_STAT_NO_HANG.
+ */
+void drm_sched_start(struct drm_gpu_scheduler *sched, int errno)
+{
+ struct drm_sched_job *s_job, *tmp;
+
+ /*
+ * Locking the list is not required here as the scheduler's work items
+ * are currently not running, so no new jobs are being inserted or
+ * removed. Also concurrent GPU recovers can't run in parallel.
+ */
+ list_for_each_entry_safe(s_job, tmp, &sched->pending_list, list) {
+ struct dma_fence *fence = s_job->s_fence->parent;
+
+ atomic_add(s_job->credits, &sched->credit_count);
+
+ if (!fence) {
+ drm_sched_job_done(s_job, errno ?: -ECANCELED);
+ continue;
+ }
+
+ if (dma_fence_add_callback(fence, &s_job->cb,
+ drm_sched_job_done_cb))
+ drm_sched_job_done(s_job, fence->error ?: errno);
+ }
+
+ drm_sched_start_timeout_unlocked(sched);
+ drm_sched_wqueue_start(sched);
+}
+EXPORT_SYMBOL(drm_sched_start);
+
+/**
+ * drm_sched_resubmit_jobs - Deprecated, don't use in new code!
+ *
+ * @sched: scheduler instance
+ *
+ * Re-submitting jobs was a concept AMD came up as cheap way to implement
+ * recovery after a job timeout.
+ *
+ * This turned out to be not working very well. First of all there are many
+ * problem with the dma_fence implementation and requirements. Either the
+ * implementation is risking deadlocks with core memory management or violating
+ * documented implementation details of the dma_fence object.
+ *
+ * Drivers can still save and restore their state for recovery operations, but
+ * we shouldn't make this a general scheduler feature around the dma_fence
+ * interface.
+ */
+void drm_sched_resubmit_jobs(struct drm_gpu_scheduler *sched)
+{
+ struct drm_sched_job *s_job, *tmp;
+ uint64_t guilty_context;
+ bool found_guilty = false;
+ struct dma_fence *fence;
+
+ list_for_each_entry_safe(s_job, tmp, &sched->pending_list, list) {
+ struct drm_sched_fence *s_fence = s_job->s_fence;
+
+ if (!found_guilty && atomic_read(&s_job->karma) > sched->hang_limit) {
+ found_guilty = true;
+ guilty_context = s_job->s_fence->scheduled.context;
+ }
+
+ if (found_guilty && s_job->s_fence->scheduled.context == guilty_context)
+ dma_fence_set_error(&s_fence->finished, -ECANCELED);
+
+ fence = sched->ops->run_job(s_job);
+
+ if (IS_ERR_OR_NULL(fence)) {
+ if (IS_ERR(fence))
+ dma_fence_set_error(&s_fence->finished, PTR_ERR(fence));
+
+ s_job->s_fence->parent = NULL;
+ } else {
+
+ s_job->s_fence->parent = dma_fence_get(fence);
+
+ /* Drop for orignal kref_init */
+ dma_fence_put(fence);
+ }
+ }
+}
+EXPORT_SYMBOL(drm_sched_resubmit_jobs);
+
+/**
+ * drm_sched_job_init - init a scheduler job
+ * @job: scheduler job to init
+ * @entity: scheduler entity to use
+ * @credits: the number of credits this job contributes to the schedulers
+ * credit limit
+ * @owner: job owner for debugging
+ * @drm_client_id: &struct drm_file.client_id of the owner (used by trace
+ * events)
+ *
+ * Refer to drm_sched_entity_push_job() documentation
+ * for locking considerations.
+ *
+ * Drivers must make sure drm_sched_job_cleanup() if this function returns
+ * successfully, even when @job is aborted before drm_sched_job_arm() is called.
+ *
+ * Note that this function does not assign a valid value to each struct member
+ * of struct drm_sched_job. Take a look at that struct's documentation to see
+ * who sets which struct member with what lifetime.
+ *
+ * WARNING: amdgpu abuses &drm_sched.ready to signal when the hardware
+ * has died, which can mean that there's no valid runqueue for a @entity.
+ * This function returns -ENOENT in this case (which probably should be -EIO as
+ * a more meanigful return value).
+ *
+ * Returns 0 for success, negative error code otherwise.
+ */
+int drm_sched_job_init(struct drm_sched_job *job,
+ struct drm_sched_entity *entity,
+ u32 credits, void *owner,
+ uint64_t drm_client_id)
+{
+ if (!entity->rq) {
+ /* This will most likely be followed by missing frames
+ * or worse--a blank screen--leave a trail in the
+ * logs, so this can be debugged easier.
+ */
+ dev_err(job->sched->dev, "%s: entity has no rq!\n", __func__);
+ return -ENOENT;
+ }
+
+ if (unlikely(!credits)) {
+ pr_err("*ERROR* %s: credits cannot be 0!\n", __func__);
+ return -EINVAL;
+ }
+
+ /*
+ * We don't know for sure how the user has allocated. Thus, zero the
+ * struct so that unallowed (i.e., too early) usage of pointers that
+ * this function does not set is guaranteed to lead to a NULL pointer
+ * exception instead of UB.
+ */
+ memset(job, 0, sizeof(*job));
+
+ job->entity = entity;
+ job->credits = credits;
+ job->s_fence = drm_sched_fence_alloc(entity, owner, drm_client_id);
+ if (!job->s_fence)
+ return -ENOMEM;
+
+ INIT_LIST_HEAD(&job->list);
+
+ xa_init_flags(&job->dependencies, XA_FLAGS_ALLOC);
+
+ return 0;
+}
+EXPORT_SYMBOL(drm_sched_job_init);
+
+/**
+ * drm_sched_job_arm - arm a scheduler job for execution
+ * @job: scheduler job to arm
+ *
+ * This arms a scheduler job for execution. Specifically it initializes the
+ * &drm_sched_job.s_fence of @job, so that it can be attached to struct dma_resv
+ * or other places that need to track the completion of this job. It also
+ * initializes sequence numbers, which are fundamental for fence ordering.
+ *
+ * Refer to drm_sched_entity_push_job() documentation for locking
+ * considerations.
+ *
+ * Once this function was called, you *must* submit @job with
+ * drm_sched_entity_push_job().
+ *
+ * This can only be called if drm_sched_job_init() succeeded.
+ */
+void drm_sched_job_arm(struct drm_sched_job *job)
+{
+ struct drm_gpu_scheduler *sched;
+ struct drm_sched_entity *entity = job->entity;
+
+ BUG_ON(!entity);
+ drm_sched_entity_select_rq(entity);
+ sched = entity->rq->sched;
+
+ job->sched = sched;
+ job->s_priority = entity->priority;
+
+ drm_sched_fence_init(job->s_fence, job->entity);
+}
+EXPORT_SYMBOL(drm_sched_job_arm);
+
+/**
+ * drm_sched_job_add_dependency - adds the fence as a job dependency
+ * @job: scheduler job to add the dependencies to
+ * @fence: the dma_fence to add to the list of dependencies.
+ *
+ * Note that @fence is consumed in both the success and error cases.
+ *
+ * Returns:
+ * 0 on success, or an error on failing to expand the array.
+ */
+int drm_sched_job_add_dependency(struct drm_sched_job *job,
+ struct dma_fence *fence)
+{
+ struct dma_fence *entry;
+ unsigned long index;
+ u32 id = 0;
+ int ret;
+
+ if (!fence)
+ return 0;
+
+ /* Deduplicate if we already depend on a fence from the same context.
+ * This lets the size of the array of deps scale with the number of
+ * engines involved, rather than the number of BOs.
+ */
+ xa_for_each(&job->dependencies, index, entry) {
+ if (entry->context != fence->context)
+ continue;
+
+ if (dma_fence_is_later(fence, entry)) {
+ dma_fence_put(entry);
+ xa_store(&job->dependencies, index, fence, GFP_KERNEL);
+ } else {
+ dma_fence_put(fence);
+ }
+ return 0;
+ }
+
+ ret = xa_alloc(&job->dependencies, &id, fence, xa_limit_32b, GFP_KERNEL);
+ if (ret != 0)
+ dma_fence_put(fence);
+
+ return ret;
+}
+EXPORT_SYMBOL(drm_sched_job_add_dependency);
+
+/**
+ * drm_sched_job_add_syncobj_dependency - adds a syncobj's fence as a job dependency
+ * @job: scheduler job to add the dependencies to
+ * @file: drm file private pointer
+ * @handle: syncobj handle to lookup
+ * @point: timeline point
+ *
+ * This adds the fence matching the given syncobj to @job.
+ *
+ * Returns:
+ * 0 on success, or an error on failing to expand the array.
+ */
+int drm_sched_job_add_syncobj_dependency(struct drm_sched_job *job,
+ struct drm_file *file,
+ u32 handle,
+ u32 point)
+{
+ struct dma_fence *fence;
+ int ret;
+
+ ret = drm_syncobj_find_fence(file, handle, point, 0, &fence);
+ if (ret)
+ return ret;
+
+ return drm_sched_job_add_dependency(job, fence);
+}
+EXPORT_SYMBOL(drm_sched_job_add_syncobj_dependency);
+
+/**
+ * drm_sched_job_add_resv_dependencies - add all fences from the resv to the job
+ * @job: scheduler job to add the dependencies to
+ * @resv: the dma_resv object to get the fences from
+ * @usage: the dma_resv_usage to use to filter the fences
+ *
+ * This adds all fences matching the given usage from @resv to @job.
+ * Must be called with the @resv lock held.
+ *
+ * Returns:
+ * 0 on success, or an error on failing to expand the array.
+ */
+int drm_sched_job_add_resv_dependencies(struct drm_sched_job *job,
+ struct dma_resv *resv,
+ enum dma_resv_usage usage)
+{
+ struct dma_resv_iter cursor;
+ struct dma_fence *fence;
+ int ret;
+
+ dma_resv_assert_held(resv);
+
+ dma_resv_for_each_fence(&cursor, resv, usage, fence) {
+ /*
+ * As drm_sched_job_add_dependency always consumes the fence
+ * reference (even when it fails), and dma_resv_for_each_fence
+ * is not obtaining one, we need to grab one before calling.
+ */
+ ret = drm_sched_job_add_dependency(job, dma_fence_get(fence));
+ if (ret)
+ return ret;
+ }
+ return 0;
+}
+EXPORT_SYMBOL(drm_sched_job_add_resv_dependencies);
+
+/**
+ * drm_sched_job_add_implicit_dependencies - adds implicit dependencies as job
+ * dependencies
+ * @job: scheduler job to add the dependencies to
+ * @obj: the gem object to add new dependencies from.
+ * @write: whether the job might write the object (so we need to depend on
+ * shared fences in the reservation object).
+ *
+ * This should be called after drm_gem_lock_reservations() on your array of
+ * GEM objects used in the job but before updating the reservations with your
+ * own fences.
+ *
+ * Returns:
+ * 0 on success, or an error on failing to expand the array.
+ */
+int drm_sched_job_add_implicit_dependencies(struct drm_sched_job *job,
+ struct drm_gem_object *obj,
+ bool write)
+{
+ return drm_sched_job_add_resv_dependencies(job, obj->resv,
+ dma_resv_usage_rw(write));
+}
+EXPORT_SYMBOL(drm_sched_job_add_implicit_dependencies);
+
+/**
+ * drm_sched_job_has_dependency - check whether fence is the job's dependency
+ * @job: scheduler job to check
+ * @fence: fence to look for
+ *
+ * Returns:
+ * True if @fence is found within the job's dependencies, or otherwise false.
+ */
+bool drm_sched_job_has_dependency(struct drm_sched_job *job,
+ struct dma_fence *fence)
+{
+ struct dma_fence *f;
+ unsigned long index;
+
+ xa_for_each(&job->dependencies, index, f) {
+ if (f == fence)
+ return true;
+ }
+
+ return false;
+}
+EXPORT_SYMBOL(drm_sched_job_has_dependency);
+
+/**
+ * drm_sched_job_cleanup - clean up scheduler job resources
+ * @job: scheduler job to clean up
+ *
+ * Cleans up the resources allocated with drm_sched_job_init().
+ *
+ * Drivers should call this from their error unwind code if @job is aborted
+ * before drm_sched_job_arm() is called.
+ *
+ * drm_sched_job_arm() is a point of no return since it initializes the fences
+ * and their sequence number etc. Once that function has been called, you *must*
+ * submit it with drm_sched_entity_push_job() and cannot simply abort it by
+ * calling drm_sched_job_cleanup().
+ *
+ * This function should be called in the &drm_sched_backend_ops.free_job callback.
+ */
+void drm_sched_job_cleanup(struct drm_sched_job *job)
+{
+ struct dma_fence *fence;
+ unsigned long index;
+
+ if (kref_read(&job->s_fence->finished.refcount)) {
+ /* The job has been processed by the scheduler, i.e.,
+ * drm_sched_job_arm() and drm_sched_entity_push_job() have
+ * been called.
+ */
+ dma_fence_put(&job->s_fence->finished);
+ } else {
+ /* The job was aborted before it has been committed to be run;
+ * notably, drm_sched_job_arm() has not been called.
+ */
+ drm_sched_fence_free(job->s_fence);
+ }
+
+ job->s_fence = NULL;
+
+ xa_for_each(&job->dependencies, index, fence) {
+ dma_fence_put(fence);
+ }
+ xa_destroy(&job->dependencies);
+
+}
+EXPORT_SYMBOL(drm_sched_job_cleanup);
+
+/**
+ * drm_sched_wakeup - Wake up the scheduler if it is ready to queue
+ * @sched: scheduler instance
+ *
+ * Wake up the scheduler if we can queue jobs.
+ */
+void drm_sched_wakeup(struct drm_gpu_scheduler *sched)
+{
+ drm_sched_run_job_queue(sched);
+}
+
+/**
+ * drm_sched_select_entity - Select next entity to process
+ *
+ * @sched: scheduler instance
+ *
+ * Return an entity to process or NULL if none are found.
+ *
+ * Note, that we break out of the for-loop when "entity" is non-null, which can
+ * also be an error-pointer--this assures we don't process lower priority
+ * run-queues. See comments in the respectively called functions.
+ */
+static struct drm_sched_entity *
+drm_sched_select_entity(struct drm_gpu_scheduler *sched)
+{
+ struct drm_sched_entity *entity;
+ int i;
+
+ /* Start with the highest priority.
+ */
+ for (i = DRM_SCHED_PRIORITY_KERNEL; i < sched->num_rqs; i++) {
+ entity = drm_sched_policy == DRM_SCHED_POLICY_FIFO ?
+ drm_sched_rq_select_entity_fifo(sched, sched->sched_rq[i]) :
+ drm_sched_rq_select_entity_rr(sched, sched->sched_rq[i]);
+ if (entity)
+ break;
+ }
+
+ return IS_ERR(entity) ? NULL : entity;
+}
+
+/**
+ * drm_sched_get_finished_job - fetch the next finished job to be destroyed
+ *
+ * @sched: scheduler instance
+ * @have_more: are there more finished jobs on the list
+ *
+ * Informs the caller through @have_more whether there are more finished jobs
+ * besides the returned one.
+ *
+ * Returns the next finished job from the pending list (if there is one)
+ * ready for it to be destroyed.
+ */
+static struct drm_sched_job *
+drm_sched_get_finished_job(struct drm_gpu_scheduler *sched, bool *have_more)
+{
+ struct drm_sched_job *job, *next;
+
+ spin_lock(&sched->job_list_lock);
+
+ job = list_first_entry_or_null(&sched->pending_list,
+ struct drm_sched_job, list);
+ if (job && dma_fence_is_signaled(&job->s_fence->finished)) {
+ /* remove job from pending_list */
+ list_del_init(&job->list);
+
+ /* cancel this job's TO timer */
+ cancel_delayed_work(&sched->work_tdr);
+
+ *have_more = false;
+ next = list_first_entry_or_null(&sched->pending_list,
+ typeof(*next), list);
+ if (next) {
+ /* make the scheduled timestamp more accurate */
+ if (test_bit(DMA_FENCE_FLAG_TIMESTAMP_BIT,
+ &next->s_fence->scheduled.flags))
+ next->s_fence->scheduled.timestamp =
+ dma_fence_timestamp(&job->s_fence->finished);
+
+ *have_more = dma_fence_is_signaled(&next->s_fence->finished);
+
+ /* start TO timer for next job */
+ drm_sched_start_timeout(sched);
+ }
+ } else {
+ job = NULL;
+ }
+
+ spin_unlock(&sched->job_list_lock);
+
+ return job;
+}
+
+/**
+ * drm_sched_pick_best - Get a drm sched from a sched_list with the least load
+ * @sched_list: list of drm_gpu_schedulers
+ * @num_sched_list: number of drm_gpu_schedulers in the sched_list
+ *
+ * Returns pointer of the sched with the least load or NULL if none of the
+ * drm_gpu_schedulers are ready
+ */
+struct drm_gpu_scheduler *
+drm_sched_pick_best(struct drm_gpu_scheduler **sched_list,
+ unsigned int num_sched_list)
+{
+ struct drm_gpu_scheduler *sched, *picked_sched = NULL;
+ int i;
+ unsigned int min_score = UINT_MAX, num_score;
+
+ for (i = 0; i < num_sched_list; ++i) {
+ sched = sched_list[i];
+
+ if (!sched->ready) {
+ DRM_WARN("scheduler %s is not ready, skipping",
+ sched->name);
+ continue;
+ }
+
+ num_score = atomic_read(sched->score);
+ if (num_score < min_score) {
+ min_score = num_score;
+ picked_sched = sched;
+ }
+ }
+
+ return picked_sched;
+}
+EXPORT_SYMBOL(drm_sched_pick_best);
+
+/**
+ * drm_sched_free_job_work - worker to call free_job
+ *
+ * @w: free job work
+ */
+static void drm_sched_free_job_work(struct work_struct *w)
+{
+ struct drm_gpu_scheduler *sched =
+ container_of(w, struct drm_gpu_scheduler, work_free_job);
+ struct drm_sched_job *job;
+ bool have_more;
+
+ job = drm_sched_get_finished_job(sched, &have_more);
+ if (job) {
+ sched->ops->free_job(job);
+ if (have_more)
+ drm_sched_run_free_queue(sched);
+ }
+
+ drm_sched_run_job_queue(sched);
+}
+
+/**
+ * drm_sched_run_job_work - worker to call run_job
+ *
+ * @w: run job work
+ */
+static void drm_sched_run_job_work(struct work_struct *w)
+{
+ struct drm_gpu_scheduler *sched =
+ container_of(w, struct drm_gpu_scheduler, work_run_job);
+ struct drm_sched_entity *entity;
+ struct dma_fence *fence;
+ struct drm_sched_fence *s_fence;
+ struct drm_sched_job *sched_job;
+ int r;
+
+ /* Find entity with a ready job */
+ entity = drm_sched_select_entity(sched);
+ if (!entity) {
+ /*
+ * Either no more work to do, or the next ready job needs more
+ * credits than the scheduler has currently available.
+ */
+ return;
+ }
+
+ sched_job = drm_sched_entity_pop_job(entity);
+ if (!sched_job) {
+ complete_all(&entity->entity_idle);
+ drm_sched_run_job_queue(sched);
+ return;
+ }
+
+ s_fence = sched_job->s_fence;
+
+ atomic_add(sched_job->credits, &sched->credit_count);
+ drm_sched_job_begin(sched_job);
+
+ trace_drm_sched_job_run(sched_job, entity);
+ /*
+ * The run_job() callback must by definition return a fence whose
+ * refcount has been incremented for the scheduler already.
+ */
+ fence = sched->ops->run_job(sched_job);
+ complete_all(&entity->entity_idle);
+ drm_sched_fence_scheduled(s_fence, fence);
+
+ if (!IS_ERR_OR_NULL(fence)) {
+ r = dma_fence_add_callback(fence, &sched_job->cb,
+ drm_sched_job_done_cb);
+ if (r == -ENOENT)
+ drm_sched_job_done(sched_job, fence->error);
+ else if (r)
+ DRM_DEV_ERROR(sched->dev, "fence add callback failed (%d)\n", r);
+
+ dma_fence_put(fence);
+ } else {
+ drm_sched_job_done(sched_job, IS_ERR(fence) ?
+ PTR_ERR(fence) : 0);
+ }
+
+ wake_up(&sched->job_scheduled);
+ drm_sched_run_job_queue(sched);
+}
+
+static struct workqueue_struct *drm_sched_alloc_wq(const char *name)
+{
+#if (IS_ENABLED(CONFIG_LOCKDEP))
+ static struct lockdep_map map = {
+ .name = "drm_sched_lockdep_map"
+ };
+
+ /*
+ * Avoid leaking a lockdep map on each drm sched creation and
+ * destruction by using a single lockdep map for all drm sched
+ * allocated submit_wq.
+ */
+
+ return alloc_ordered_workqueue_lockdep_map(name, WQ_MEM_RECLAIM, &map);
+#else
+ return alloc_ordered_workqueue(name, WQ_MEM_RECLAIM);
+#endif
+}
+
+/**
+ * drm_sched_init - Init a gpu scheduler instance
+ *
+ * @sched: scheduler instance
+ * @args: scheduler initialization arguments
+ *
+ * Return 0 on success, otherwise error code.
+ */
+int drm_sched_init(struct drm_gpu_scheduler *sched, const struct drm_sched_init_args *args)
+{
+ int i;
+
+ sched->ops = args->ops;
+ sched->credit_limit = args->credit_limit;
+ sched->name = args->name;
+ sched->timeout = args->timeout;
+ sched->hang_limit = args->hang_limit;
+ sched->timeout_wq = args->timeout_wq ? args->timeout_wq : system_percpu_wq;
+ sched->score = args->score ? args->score : &sched->_score;
+ sched->dev = args->dev;
+
+ if (args->num_rqs > DRM_SCHED_PRIORITY_COUNT) {
+ /* This is a gross violation--tell drivers what the problem is.
+ */
+ dev_err(sched->dev, "%s: num_rqs cannot be greater than DRM_SCHED_PRIORITY_COUNT\n",
+ __func__);
+ return -EINVAL;
+ } else if (sched->sched_rq) {
+ /* Not an error, but warn anyway so drivers can
+ * fine-tune their DRM calling order, and return all
+ * is good.
+ */
+ dev_warn(sched->dev, "%s: scheduler already initialized!\n", __func__);
+ return 0;
+ }
+
+ if (args->submit_wq) {
+ sched->submit_wq = args->submit_wq;
+ sched->own_submit_wq = false;
+ } else {
+ sched->submit_wq = drm_sched_alloc_wq(args->name);
+ if (!sched->submit_wq)
+ return -ENOMEM;
+
+ sched->own_submit_wq = true;
+ }
+
+ sched->sched_rq = kmalloc_array(args->num_rqs, sizeof(*sched->sched_rq),
+ GFP_KERNEL | __GFP_ZERO);
+ if (!sched->sched_rq)
+ goto Out_check_own;
+ sched->num_rqs = args->num_rqs;
+ for (i = DRM_SCHED_PRIORITY_KERNEL; i < sched->num_rqs; i++) {
+ sched->sched_rq[i] = kzalloc(sizeof(*sched->sched_rq[i]), GFP_KERNEL);
+ if (!sched->sched_rq[i])
+ goto Out_unroll;
+ drm_sched_rq_init(sched, sched->sched_rq[i]);
+ }
+
+ init_waitqueue_head(&sched->job_scheduled);
+ INIT_LIST_HEAD(&sched->pending_list);
+ spin_lock_init(&sched->job_list_lock);
+ atomic_set(&sched->credit_count, 0);
+ INIT_DELAYED_WORK(&sched->work_tdr, drm_sched_job_timedout);
+ INIT_WORK(&sched->work_run_job, drm_sched_run_job_work);
+ INIT_WORK(&sched->work_free_job, drm_sched_free_job_work);
+ atomic_set(&sched->_score, 0);
+ atomic64_set(&sched->job_id_count, 0);
+ sched->pause_submit = false;
+
+ sched->ready = true;
+ return 0;
+Out_unroll:
+ for (--i ; i >= DRM_SCHED_PRIORITY_KERNEL; i--)
+ kfree(sched->sched_rq[i]);
+
+ kfree(sched->sched_rq);
+ sched->sched_rq = NULL;
+Out_check_own:
+ if (sched->own_submit_wq)
+ destroy_workqueue(sched->submit_wq);
+ dev_err(sched->dev, "%s: Failed to setup GPU scheduler--out of memory\n", __func__);
+ return -ENOMEM;
+}
+EXPORT_SYMBOL(drm_sched_init);
+
+static void drm_sched_cancel_remaining_jobs(struct drm_gpu_scheduler *sched)
+{
+ struct drm_sched_job *job, *tmp;
+
+ /* All other accessors are stopped. No locking necessary. */
+ list_for_each_entry_safe_reverse(job, tmp, &sched->pending_list, list) {
+ sched->ops->cancel_job(job);
+ list_del(&job->list);
+ sched->ops->free_job(job);
+ }
+}
+
+/**
+ * drm_sched_fini - Destroy a gpu scheduler
+ *
+ * @sched: scheduler instance
+ *
+ * Tears down and cleans up the scheduler.
+ *
+ * This stops submission of new jobs to the hardware through &struct
+ * drm_sched_backend_ops.run_job. If &struct drm_sched_backend_ops.cancel_job
+ * is implemented, all jobs will be canceled through it and afterwards cleaned
+ * up through &struct drm_sched_backend_ops.free_job. If cancel_job is not
+ * implemented, memory could leak.
+ */
+void drm_sched_fini(struct drm_gpu_scheduler *sched)
+{
+ struct drm_sched_entity *s_entity;
+ int i;
+
+ drm_sched_wqueue_stop(sched);
+
+ for (i = DRM_SCHED_PRIORITY_KERNEL; i < sched->num_rqs; i++) {
+ struct drm_sched_rq *rq = sched->sched_rq[i];
+
+ spin_lock(&rq->lock);
+ list_for_each_entry(s_entity, &rq->entities, list) {
+ /*
+ * Prevents reinsertion and marks job_queue as idle,
+ * it will be removed from the rq in drm_sched_entity_fini()
+ * eventually
+ *
+ * FIXME:
+ * This lacks the proper spin_lock(&s_entity->lock) and
+ * is, therefore, a race condition. Most notably, it
+ * can race with drm_sched_entity_push_job(). The lock
+ * cannot be taken here, however, because this would
+ * lead to lock inversion -> deadlock.
+ *
+ * The best solution probably is to enforce the life
+ * time rule of all entities having to be torn down
+ * before their scheduler. Then, however, locking could
+ * be dropped alltogether from this function.
+ *
+ * For now, this remains a potential race in all
+ * drivers that keep entities alive for longer than
+ * the scheduler.
+ *
+ * The READ_ONCE() is there to make the lockless read
+ * (warning about the lockless write below) slightly
+ * less broken...
+ */
+ if (!READ_ONCE(s_entity->stopped))
+ dev_warn(sched->dev, "Tearing down scheduler with active entities!\n");
+ s_entity->stopped = true;
+ }
+ spin_unlock(&rq->lock);
+ kfree(sched->sched_rq[i]);
+ }
+
+ /* Wakeup everyone stuck in drm_sched_entity_flush for this scheduler */
+ wake_up_all(&sched->job_scheduled);
+
+ /* Confirm no work left behind accessing device structures */
+ cancel_delayed_work_sync(&sched->work_tdr);
+
+ /* Avoid memory leaks if supported by the driver. */
+ if (sched->ops->cancel_job)
+ drm_sched_cancel_remaining_jobs(sched);
+
+ if (sched->own_submit_wq)
+ destroy_workqueue(sched->submit_wq);
+ sched->ready = false;
+ kfree(sched->sched_rq);
+ sched->sched_rq = NULL;
+
+ if (!list_empty(&sched->pending_list))
+ dev_warn(sched->dev, "Tearing down scheduler while jobs are pending!\n");
+}
+EXPORT_SYMBOL(drm_sched_fini);
+
+/**
+ * drm_sched_increase_karma - Update sched_entity guilty flag
+ *
+ * @bad: The job guilty of time out
+ *
+ * Increment on every hang caused by the 'bad' job. If this exceeds the hang
+ * limit of the scheduler then the respective sched entity is marked guilty and
+ * jobs from it will not be scheduled further
+ */
+void drm_sched_increase_karma(struct drm_sched_job *bad)
+{
+ int i;
+ struct drm_sched_entity *tmp;
+ struct drm_sched_entity *entity;
+ struct drm_gpu_scheduler *sched = bad->sched;
+
+ /* don't change @bad's karma if it's from KERNEL RQ,
+ * because sometimes GPU hang would cause kernel jobs (like VM updating jobs)
+ * corrupt but keep in mind that kernel jobs always considered good.
+ */
+ if (bad->s_priority != DRM_SCHED_PRIORITY_KERNEL) {
+ atomic_inc(&bad->karma);
+
+ for (i = DRM_SCHED_PRIORITY_HIGH; i < sched->num_rqs; i++) {
+ struct drm_sched_rq *rq = sched->sched_rq[i];
+
+ spin_lock(&rq->lock);
+ list_for_each_entry_safe(entity, tmp, &rq->entities, list) {
+ if (bad->s_fence->scheduled.context ==
+ entity->fence_context) {
+ if (entity->guilty)
+ atomic_set(entity->guilty, 1);
+ break;
+ }
+ }
+ spin_unlock(&rq->lock);
+ if (&entity->list != &rq->entities)
+ break;
+ }
+ }
+}
+EXPORT_SYMBOL(drm_sched_increase_karma);
+
+/**
+ * drm_sched_wqueue_ready - Is the scheduler ready for submission
+ *
+ * @sched: scheduler instance
+ *
+ * Returns true if submission is ready
+ */
+bool drm_sched_wqueue_ready(struct drm_gpu_scheduler *sched)
+{
+ return sched->ready;
+}
+EXPORT_SYMBOL(drm_sched_wqueue_ready);
+
+/**
+ * drm_sched_wqueue_stop - stop scheduler submission
+ * @sched: scheduler instance
+ *
+ * Stops the scheduler from pulling new jobs from entities. It also stops
+ * freeing jobs automatically through drm_sched_backend_ops.free_job().
+ */
+void drm_sched_wqueue_stop(struct drm_gpu_scheduler *sched)
+{
+ WRITE_ONCE(sched->pause_submit, true);
+ cancel_work_sync(&sched->work_run_job);
+ cancel_work_sync(&sched->work_free_job);
+}
+EXPORT_SYMBOL(drm_sched_wqueue_stop);
+
+/**
+ * drm_sched_wqueue_start - start scheduler submission
+ * @sched: scheduler instance
+ *
+ * Restarts the scheduler after drm_sched_wqueue_stop() has stopped it.
+ *
+ * This function is not necessary for 'conventional' startup. The scheduler is
+ * fully operational after drm_sched_init() succeeded.
+ */
+void drm_sched_wqueue_start(struct drm_gpu_scheduler *sched)
+{
+ WRITE_ONCE(sched->pause_submit, false);
+ queue_work(sched->submit_wq, &sched->work_run_job);
+ queue_work(sched->submit_wq, &sched->work_free_job);
+}
+EXPORT_SYMBOL(drm_sched_wqueue_start);
diff --git a/drivers/gpu/drm/scheduler/tests/Makefile b/drivers/gpu/drm/scheduler/tests/Makefile
new file mode 100644
index 000000000000..5bf707bad373
--- /dev/null
+++ b/drivers/gpu/drm/scheduler/tests/Makefile
@@ -0,0 +1,7 @@
+# SPDX-License-Identifier: GPL-2.0
+
+drm-sched-tests-y := \
+ mock_scheduler.o \
+ tests_basic.o
+
+obj-$(CONFIG_DRM_SCHED_KUNIT_TEST) += drm-sched-tests.o
diff --git a/drivers/gpu/drm/scheduler/tests/mock_scheduler.c b/drivers/gpu/drm/scheduler/tests/mock_scheduler.c
new file mode 100644
index 000000000000..8e9ae7d980eb
--- /dev/null
+++ b/drivers/gpu/drm/scheduler/tests/mock_scheduler.c
@@ -0,0 +1,370 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2025 Valve Corporation */
+
+#include "sched_tests.h"
+
+/*
+ * Here we implement the mock "GPU" (or the scheduler backend) which is used by
+ * the DRM scheduler unit tests in order to exercise the core functionality.
+ *
+ * Test cases are implemented in a separate file.
+ */
+
+/**
+ * drm_mock_sched_entity_new - Create a new mock scheduler entity
+ *
+ * @test: KUnit test owning the entity
+ * @priority: Scheduling priority
+ * @sched: Mock scheduler on which the entity can be scheduled
+ *
+ * Returns: New mock scheduler entity with allocation managed by the test
+ */
+struct drm_mock_sched_entity *
+drm_mock_sched_entity_new(struct kunit *test,
+ enum drm_sched_priority priority,
+ struct drm_mock_scheduler *sched)
+{
+ struct drm_mock_sched_entity *entity;
+ struct drm_gpu_scheduler *drm_sched;
+ int ret;
+
+ entity = kunit_kzalloc(test, sizeof(*entity), GFP_KERNEL);
+ KUNIT_ASSERT_NOT_NULL(test, entity);
+
+ drm_sched = &sched->base;
+ ret = drm_sched_entity_init(&entity->base,
+ priority,
+ &drm_sched, 1,
+ NULL);
+ KUNIT_ASSERT_EQ(test, ret, 0);
+
+ entity->test = test;
+
+ return entity;
+}
+
+/**
+ * drm_mock_sched_entity_free - Destroys a mock scheduler entity
+ *
+ * @entity: Entity to destroy
+ *
+ * To be used from the test cases once done with the entity.
+ */
+void drm_mock_sched_entity_free(struct drm_mock_sched_entity *entity)
+{
+ drm_sched_entity_destroy(&entity->base);
+}
+
+static void drm_mock_sched_job_complete(struct drm_mock_sched_job *job)
+{
+ struct drm_mock_scheduler *sched =
+ drm_sched_to_mock_sched(job->base.sched);
+
+ lockdep_assert_held(&sched->lock);
+
+ job->flags |= DRM_MOCK_SCHED_JOB_DONE;
+ list_del(&job->link);
+ dma_fence_signal_locked(&job->hw_fence);
+ complete(&job->done);
+}
+
+static enum hrtimer_restart
+drm_mock_sched_job_signal_timer(struct hrtimer *hrtimer)
+{
+ struct drm_mock_sched_job *job =
+ container_of(hrtimer, typeof(*job), timer);
+ struct drm_mock_scheduler *sched =
+ drm_sched_to_mock_sched(job->base.sched);
+ struct drm_mock_sched_job *next;
+ ktime_t now = ktime_get();
+ unsigned long flags;
+ LIST_HEAD(signal);
+
+ spin_lock_irqsave(&sched->lock, flags);
+ list_for_each_entry_safe(job, next, &sched->job_list, link) {
+ if (!job->duration_us)
+ break;
+
+ if (ktime_before(now, job->finish_at))
+ break;
+
+ sched->hw_timeline.cur_seqno = job->hw_fence.seqno;
+ drm_mock_sched_job_complete(job);
+ }
+ spin_unlock_irqrestore(&sched->lock, flags);
+
+ return HRTIMER_NORESTART;
+}
+
+/**
+ * drm_mock_sched_job_new - Create a new mock scheduler job
+ *
+ * @test: KUnit test owning the job
+ * @entity: Scheduler entity of the job
+ *
+ * Returns: New mock scheduler job with allocation managed by the test
+ */
+struct drm_mock_sched_job *
+drm_mock_sched_job_new(struct kunit *test,
+ struct drm_mock_sched_entity *entity)
+{
+ struct drm_mock_sched_job *job;
+ int ret;
+
+ job = kunit_kzalloc(test, sizeof(*job), GFP_KERNEL);
+ KUNIT_ASSERT_NOT_NULL(test, job);
+
+ ret = drm_sched_job_init(&job->base,
+ &entity->base,
+ 1,
+ NULL,
+ 1);
+ KUNIT_ASSERT_EQ(test, ret, 0);
+
+ job->test = test;
+
+ init_completion(&job->done);
+ INIT_LIST_HEAD(&job->link);
+ hrtimer_setup(&job->timer, drm_mock_sched_job_signal_timer,
+ CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
+
+ return job;
+}
+
+static const char *drm_mock_sched_hw_fence_driver_name(struct dma_fence *fence)
+{
+ return "drm_mock_sched";
+}
+
+static const char *
+drm_mock_sched_hw_fence_timeline_name(struct dma_fence *fence)
+{
+ struct drm_mock_sched_job *job =
+ container_of(fence, typeof(*job), hw_fence);
+
+ return (const char *)job->base.sched->name;
+}
+
+static void drm_mock_sched_hw_fence_release(struct dma_fence *fence)
+{
+ struct drm_mock_sched_job *job =
+ container_of(fence, typeof(*job), hw_fence);
+
+ hrtimer_cancel(&job->timer);
+
+ /* Containing job is freed by the kunit framework */
+}
+
+static const struct dma_fence_ops drm_mock_sched_hw_fence_ops = {
+ .get_driver_name = drm_mock_sched_hw_fence_driver_name,
+ .get_timeline_name = drm_mock_sched_hw_fence_timeline_name,
+ .release = drm_mock_sched_hw_fence_release,
+};
+
+static struct dma_fence *mock_sched_run_job(struct drm_sched_job *sched_job)
+{
+ struct drm_mock_scheduler *sched =
+ drm_sched_to_mock_sched(sched_job->sched);
+ struct drm_mock_sched_job *job = drm_sched_job_to_mock_job(sched_job);
+
+ dma_fence_init(&job->hw_fence,
+ &drm_mock_sched_hw_fence_ops,
+ &sched->lock,
+ sched->hw_timeline.context,
+ atomic_inc_return(&sched->hw_timeline.next_seqno));
+
+ dma_fence_get(&job->hw_fence); /* Reference for the job_list */
+
+ spin_lock_irq(&sched->lock);
+ if (job->duration_us) {
+ ktime_t prev_finish_at = 0;
+
+ if (!list_empty(&sched->job_list)) {
+ struct drm_mock_sched_job *prev =
+ list_last_entry(&sched->job_list, typeof(*prev),
+ link);
+
+ prev_finish_at = prev->finish_at;
+ }
+
+ if (!prev_finish_at)
+ prev_finish_at = ktime_get();
+
+ job->finish_at = ktime_add_us(prev_finish_at, job->duration_us);
+ }
+ list_add_tail(&job->link, &sched->job_list);
+ if (job->finish_at)
+ hrtimer_start(&job->timer, job->finish_at, HRTIMER_MODE_ABS);
+ spin_unlock_irq(&sched->lock);
+
+ return &job->hw_fence;
+}
+
+/*
+ * Normally, drivers would take appropriate measures in this callback, such as
+ * killing the entity the faulty job is associated with, resetting the hardware
+ * and / or resubmitting non-faulty jobs.
+ *
+ * For the mock scheduler, there are no hardware rings to be resetted nor jobs
+ * to be resubmitted. Thus, this function merely ensures that
+ * a) timedout fences get signaled properly and removed from the pending list
+ * b) the mock scheduler framework gets informed about the timeout via a flag
+ * c) The drm_sched_job, not longer needed, gets freed
+ */
+static enum drm_gpu_sched_stat
+mock_sched_timedout_job(struct drm_sched_job *sched_job)
+{
+ struct drm_mock_scheduler *sched = drm_sched_to_mock_sched(sched_job->sched);
+ struct drm_mock_sched_job *job = drm_sched_job_to_mock_job(sched_job);
+ unsigned long flags;
+
+ if (job->flags & DRM_MOCK_SCHED_JOB_DONT_RESET) {
+ job->flags |= DRM_MOCK_SCHED_JOB_RESET_SKIPPED;
+ return DRM_GPU_SCHED_STAT_NO_HANG;
+ }
+
+ spin_lock_irqsave(&sched->lock, flags);
+ if (!dma_fence_is_signaled_locked(&job->hw_fence)) {
+ list_del(&job->link);
+ job->flags |= DRM_MOCK_SCHED_JOB_TIMEDOUT;
+ dma_fence_set_error(&job->hw_fence, -ETIMEDOUT);
+ dma_fence_signal_locked(&job->hw_fence);
+ }
+ spin_unlock_irqrestore(&sched->lock, flags);
+
+ dma_fence_put(&job->hw_fence);
+ drm_sched_job_cleanup(sched_job);
+ /* Mock job itself is freed by the kunit framework. */
+
+ return DRM_GPU_SCHED_STAT_RESET;
+}
+
+static void mock_sched_free_job(struct drm_sched_job *sched_job)
+{
+ struct drm_mock_sched_job *job = drm_sched_job_to_mock_job(sched_job);
+
+ dma_fence_put(&job->hw_fence);
+ drm_sched_job_cleanup(sched_job);
+
+ /* Mock job itself is freed by the kunit framework. */
+}
+
+static void mock_sched_cancel_job(struct drm_sched_job *sched_job)
+{
+ struct drm_mock_scheduler *sched = drm_sched_to_mock_sched(sched_job->sched);
+ struct drm_mock_sched_job *job = drm_sched_job_to_mock_job(sched_job);
+ unsigned long flags;
+
+ hrtimer_cancel(&job->timer);
+
+ spin_lock_irqsave(&sched->lock, flags);
+ if (!dma_fence_is_signaled_locked(&job->hw_fence)) {
+ list_del(&job->link);
+ dma_fence_set_error(&job->hw_fence, -ECANCELED);
+ dma_fence_signal_locked(&job->hw_fence);
+ }
+ spin_unlock_irqrestore(&sched->lock, flags);
+
+ /*
+ * The GPU Scheduler will call drm_sched_backend_ops.free_job(), still.
+ * Mock job itself is freed by the kunit framework.
+ */
+}
+
+static const struct drm_sched_backend_ops drm_mock_scheduler_ops = {
+ .run_job = mock_sched_run_job,
+ .timedout_job = mock_sched_timedout_job,
+ .free_job = mock_sched_free_job,
+ .cancel_job = mock_sched_cancel_job,
+};
+
+/**
+ * drm_mock_sched_new - Create a new mock scheduler
+ *
+ * @test: KUnit test owning the job
+ * @timeout: Job timeout to set
+ *
+ * Returns: New mock scheduler with allocation managed by the test
+ */
+struct drm_mock_scheduler *drm_mock_sched_new(struct kunit *test, long timeout)
+{
+ struct drm_sched_init_args args = {
+ .ops = &drm_mock_scheduler_ops,
+ .num_rqs = DRM_SCHED_PRIORITY_COUNT,
+ .credit_limit = U32_MAX,
+ .hang_limit = 1,
+ .timeout = timeout,
+ .name = "drm-mock-scheduler",
+ };
+ struct drm_mock_scheduler *sched;
+ int ret;
+
+ sched = kunit_kzalloc(test, sizeof(*sched), GFP_KERNEL);
+ KUNIT_ASSERT_NOT_NULL(test, sched);
+
+ ret = drm_sched_init(&sched->base, &args);
+ KUNIT_ASSERT_EQ(test, ret, 0);
+
+ sched->test = test;
+ sched->hw_timeline.context = dma_fence_context_alloc(1);
+ atomic_set(&sched->hw_timeline.next_seqno, 0);
+ INIT_LIST_HEAD(&sched->job_list);
+ spin_lock_init(&sched->lock);
+
+ return sched;
+}
+
+/**
+ * drm_mock_sched_fini - Destroys a mock scheduler
+ *
+ * @sched: Scheduler to destroy
+ *
+ * To be used from the test cases once done with the scheduler.
+ */
+void drm_mock_sched_fini(struct drm_mock_scheduler *sched)
+{
+ drm_sched_fini(&sched->base);
+}
+
+/**
+ * drm_mock_sched_advance - Advances the mock scheduler timeline
+ *
+ * @sched: Scheduler timeline to advance
+ * @num: By how many jobs to advance
+ *
+ * Advancing the scheduler timeline by a number of seqnos will trigger
+ * signalling of the hardware fences and unlinking the jobs from the internal
+ * scheduler tracking.
+ *
+ * This can be used from test cases which want complete control of the simulated
+ * job execution timing. For example submitting one job with no set duration
+ * would never complete it before test cases advances the timeline by one.
+ */
+unsigned int drm_mock_sched_advance(struct drm_mock_scheduler *sched,
+ unsigned int num)
+{
+ struct drm_mock_sched_job *job, *next;
+ unsigned int found = 0;
+ unsigned long flags;
+ LIST_HEAD(signal);
+
+ spin_lock_irqsave(&sched->lock, flags);
+ if (WARN_ON_ONCE(sched->hw_timeline.cur_seqno + num <
+ sched->hw_timeline.cur_seqno))
+ goto unlock;
+ sched->hw_timeline.cur_seqno += num;
+ list_for_each_entry_safe(job, next, &sched->job_list, link) {
+ if (sched->hw_timeline.cur_seqno < job->hw_fence.seqno)
+ break;
+
+ drm_mock_sched_job_complete(job);
+ found++;
+ }
+unlock:
+ spin_unlock_irqrestore(&sched->lock, flags);
+
+ return found;
+}
+
+MODULE_DESCRIPTION("DRM mock scheduler and tests");
+MODULE_LICENSE("GPL");
diff --git a/drivers/gpu/drm/scheduler/tests/sched_tests.h b/drivers/gpu/drm/scheduler/tests/sched_tests.h
new file mode 100644
index 000000000000..553d45abd057
--- /dev/null
+++ b/drivers/gpu/drm/scheduler/tests/sched_tests.h
@@ -0,0 +1,224 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright (c) 2025 Valve Corporation */
+
+#ifndef _SCHED_TESTS_H_
+#define _SCHED_TESTS_H_
+
+#include <kunit/test.h>
+#include <linux/atomic.h>
+#include <linux/completion.h>
+#include <linux/dma-fence.h>
+#include <linux/hrtimer.h>
+#include <linux/ktime.h>
+#include <linux/list.h>
+#include <linux/mutex.h>
+#include <linux/types.h>
+
+#include <drm/gpu_scheduler.h>
+
+/*
+ * DOC: Mock DRM scheduler data structures
+ *
+ * drm_mock_* data structures are used to implement a mock "GPU".
+ *
+ * They subclass the core DRM scheduler objects and add their data on top, which
+ * enables tracking the submitted jobs and simulating their execution with the
+ * attributes as specified by the test case.
+ */
+
+/**
+ * struct drm_mock_scheduler - implements a trivial mock GPU execution engine
+ *
+ * @base: DRM scheduler base class
+ * @test: Backpointer to owning the kunit test case
+ * @lock: Lock to protect the simulated @hw_timeline and @job_list
+ * @job_list: List of jobs submitted to the mock GPU
+ * @hw_timeline: Simulated hardware timeline has a @context, @next_seqno and
+ * @cur_seqno for implementing a struct dma_fence signaling the
+ * simulated job completion.
+ *
+ * Trivial mock GPU execution engine tracks submitted jobs and enables
+ * completing them strictly in submission order.
+ */
+struct drm_mock_scheduler {
+ struct drm_gpu_scheduler base;
+
+ struct kunit *test;
+
+ spinlock_t lock;
+ struct list_head job_list;
+
+ struct {
+ u64 context;
+ atomic_t next_seqno;
+ unsigned int cur_seqno;
+ } hw_timeline;
+};
+
+/**
+ * struct drm_mock_sched_entity - implements a mock GPU sched entity
+ *
+ * @base: DRM scheduler entity base class
+ * @test: Backpointer to owning the kunit test case
+ *
+ * Mock GPU sched entity is used by the test cases to submit jobs to the mock
+ * scheduler.
+ */
+struct drm_mock_sched_entity {
+ struct drm_sched_entity base;
+
+ struct kunit *test;
+};
+
+/**
+ * struct drm_mock_sched_job - implements a mock GPU job
+ *
+ * @base: DRM sched job base class
+ * @done: Completion signaling job completion.
+ * @flags: Flags designating job state.
+ * @link: List head element used by job tracking by the drm_mock_scheduler
+ * @timer: Timer used for simulating job execution duration
+ * @duration_us: Simulated job duration in micro seconds, or zero if in manual
+ * timeline advance mode
+ * @finish_at: Absolute time when the jobs with set duration will complete
+ * @lock: Lock used for @hw_fence
+ * @hw_fence: Fence returned to DRM scheduler as the hardware fence
+ * @test: Backpointer to owning the kunit test case
+ *
+ * Mock GPU sched job is used by the test cases to submit jobs to the mock
+ * scheduler.
+ */
+struct drm_mock_sched_job {
+ struct drm_sched_job base;
+
+ struct completion done;
+
+#define DRM_MOCK_SCHED_JOB_DONE 0x1
+#define DRM_MOCK_SCHED_JOB_TIMEDOUT 0x2
+#define DRM_MOCK_SCHED_JOB_DONT_RESET 0x4
+#define DRM_MOCK_SCHED_JOB_RESET_SKIPPED 0x8
+ unsigned long flags;
+
+ struct list_head link;
+ struct hrtimer timer;
+
+ unsigned int duration_us;
+ ktime_t finish_at;
+
+ struct dma_fence hw_fence;
+
+ struct kunit *test;
+};
+
+static inline struct drm_mock_scheduler *
+drm_sched_to_mock_sched(struct drm_gpu_scheduler *sched)
+{
+ return container_of(sched, struct drm_mock_scheduler, base);
+};
+
+static inline struct drm_mock_sched_entity *
+drm_sched_entity_to_mock_entity(struct drm_sched_entity *sched_entity)
+{
+ return container_of(sched_entity, struct drm_mock_sched_entity, base);
+};
+
+static inline struct drm_mock_sched_job *
+drm_sched_job_to_mock_job(struct drm_sched_job *sched_job)
+{
+ return container_of(sched_job, struct drm_mock_sched_job, base);
+};
+
+struct drm_mock_scheduler *drm_mock_sched_new(struct kunit *test,
+ long timeout);
+void drm_mock_sched_fini(struct drm_mock_scheduler *sched);
+unsigned int drm_mock_sched_advance(struct drm_mock_scheduler *sched,
+ unsigned int num);
+
+struct drm_mock_sched_entity *
+drm_mock_sched_entity_new(struct kunit *test,
+ enum drm_sched_priority priority,
+ struct drm_mock_scheduler *sched);
+void drm_mock_sched_entity_free(struct drm_mock_sched_entity *entity);
+
+struct drm_mock_sched_job *
+drm_mock_sched_job_new(struct kunit *test,
+ struct drm_mock_sched_entity *entity);
+
+/**
+ * drm_mock_sched_job_submit - Arm and submit a job in one go
+ *
+ * @job: Job to arm and submit
+ */
+static inline void drm_mock_sched_job_submit(struct drm_mock_sched_job *job)
+{
+ drm_sched_job_arm(&job->base);
+ drm_sched_entity_push_job(&job->base);
+}
+
+/**
+ * drm_mock_sched_job_set_duration_us - Set a job duration
+ *
+ * @job: Job to set the duration for
+ * @duration_us: Duration in micro seconds
+ *
+ * Jobs with duration set will be automatically completed by the mock scheduler
+ * as the timeline progresses, unless a job without a set duration is
+ * encountered in the timelime in which case calling drm_mock_sched_advance()
+ * will be required to bump the timeline.
+ */
+static inline void
+drm_mock_sched_job_set_duration_us(struct drm_mock_sched_job *job,
+ unsigned int duration_us)
+{
+ job->duration_us = duration_us;
+}
+
+/**
+ * drm_mock_sched_job_is_finished - Check if a job is finished
+ *
+ * @job: Job to check
+ *
+ * Returns: true if finished
+ */
+static inline bool
+drm_mock_sched_job_is_finished(struct drm_mock_sched_job *job)
+{
+ return job->flags & DRM_MOCK_SCHED_JOB_DONE;
+}
+
+/**
+ * drm_mock_sched_job_wait_finished - Wait until a job is finished
+ *
+ * @job: Job to wait for
+ * @timeout: Wait time in jiffies
+ *
+ * Returns: true if finished within the timeout provided, otherwise false
+ */
+static inline bool
+drm_mock_sched_job_wait_finished(struct drm_mock_sched_job *job, long timeout)
+{
+ if (job->flags & DRM_MOCK_SCHED_JOB_DONE)
+ return true;
+
+ return wait_for_completion_timeout(&job->done, timeout) != 0;
+}
+
+/**
+ * drm_mock_sched_job_wait_scheduled - Wait until a job is scheduled
+ *
+ * @job: Job to wait for
+ * @timeout: Wait time in jiffies
+ *
+ * Returns: true if scheduled within the timeout provided, otherwise false
+ */
+static inline bool
+drm_mock_sched_job_wait_scheduled(struct drm_mock_sched_job *job, long timeout)
+{
+ KUNIT_ASSERT_EQ(job->test, job->flags & DRM_MOCK_SCHED_JOB_DONE, 0);
+
+ return dma_fence_wait_timeout(&job->base.s_fence->scheduled,
+ false,
+ timeout) != 0;
+}
+
+#endif
diff --git a/drivers/gpu/drm/scheduler/tests/tests_basic.c b/drivers/gpu/drm/scheduler/tests/tests_basic.c
new file mode 100644
index 000000000000..82a41a456b0a
--- /dev/null
+++ b/drivers/gpu/drm/scheduler/tests/tests_basic.c
@@ -0,0 +1,563 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2025 Valve Corporation */
+
+#include <linux/delay.h>
+
+#include "sched_tests.h"
+
+#define MOCK_TIMEOUT (HZ / 5)
+
+/*
+ * DRM scheduler basic tests should check the basic functional correctness of
+ * the scheduler, including some very light smoke testing. More targeted tests,
+ * for example focusing on testing specific bugs and other more complicated test
+ * scenarios, should be implemented in separate source units.
+ */
+
+static int drm_sched_basic_init(struct kunit *test)
+{
+ test->priv = drm_mock_sched_new(test, MAX_SCHEDULE_TIMEOUT);
+
+ return 0;
+}
+
+static void drm_sched_basic_exit(struct kunit *test)
+{
+ struct drm_mock_scheduler *sched = test->priv;
+
+ drm_mock_sched_fini(sched);
+}
+
+static int drm_sched_timeout_init(struct kunit *test)
+{
+ test->priv = drm_mock_sched_new(test, MOCK_TIMEOUT);
+
+ return 0;
+}
+
+static void drm_sched_basic_submit(struct kunit *test)
+{
+ struct drm_mock_scheduler *sched = test->priv;
+ struct drm_mock_sched_entity *entity;
+ struct drm_mock_sched_job *job;
+ unsigned int i;
+ bool done;
+
+ /*
+ * Submit one job to the scheduler and verify that it gets scheduled
+ * and completed only when the mock hw backend processes it.
+ */
+
+ entity = drm_mock_sched_entity_new(test,
+ DRM_SCHED_PRIORITY_NORMAL,
+ sched);
+ job = drm_mock_sched_job_new(test, entity);
+
+ drm_mock_sched_job_submit(job);
+
+ done = drm_mock_sched_job_wait_scheduled(job, HZ);
+ KUNIT_ASSERT_TRUE(test, done);
+
+ done = drm_mock_sched_job_wait_finished(job, HZ / 2);
+ KUNIT_ASSERT_FALSE(test, done);
+
+ i = drm_mock_sched_advance(sched, 1);
+ KUNIT_ASSERT_EQ(test, i, 1);
+
+ done = drm_mock_sched_job_wait_finished(job, HZ);
+ KUNIT_ASSERT_TRUE(test, done);
+
+ drm_mock_sched_entity_free(entity);
+}
+
+struct drm_sched_basic_params {
+ const char *description;
+ unsigned int queue_depth;
+ unsigned int num_entities;
+ unsigned int job_us;
+ bool dep_chain;
+};
+
+static const struct drm_sched_basic_params drm_sched_basic_cases[] = {
+ {
+ .description = "A queue of jobs in a single entity",
+ .queue_depth = 100,
+ .job_us = 1000,
+ .num_entities = 1,
+ },
+ {
+ .description = "A chain of dependent jobs across multiple entities",
+ .queue_depth = 100,
+ .job_us = 1000,
+ .num_entities = 1,
+ .dep_chain = true,
+ },
+ {
+ .description = "Multiple independent job queues",
+ .queue_depth = 100,
+ .job_us = 1000,
+ .num_entities = 4,
+ },
+ {
+ .description = "Multiple inter-dependent job queues",
+ .queue_depth = 100,
+ .job_us = 1000,
+ .num_entities = 4,
+ .dep_chain = true,
+ },
+};
+
+static void
+drm_sched_basic_desc(const struct drm_sched_basic_params *params, char *desc)
+{
+ strscpy(desc, params->description, KUNIT_PARAM_DESC_SIZE);
+}
+
+KUNIT_ARRAY_PARAM(drm_sched_basic, drm_sched_basic_cases, drm_sched_basic_desc);
+
+static void drm_sched_basic_test(struct kunit *test)
+{
+ const struct drm_sched_basic_params *params = test->param_value;
+ struct drm_mock_scheduler *sched = test->priv;
+ struct drm_mock_sched_job *job, *prev = NULL;
+ struct drm_mock_sched_entity **entity;
+ unsigned int i, cur_ent = 0;
+ bool done;
+
+ entity = kunit_kcalloc(test, params->num_entities, sizeof(*entity),
+ GFP_KERNEL);
+ KUNIT_ASSERT_NOT_NULL(test, entity);
+
+ for (i = 0; i < params->num_entities; i++)
+ entity[i] = drm_mock_sched_entity_new(test,
+ DRM_SCHED_PRIORITY_NORMAL,
+ sched);
+
+ for (i = 0; i < params->queue_depth; i++) {
+ job = drm_mock_sched_job_new(test, entity[cur_ent++]);
+ cur_ent %= params->num_entities;
+ drm_mock_sched_job_set_duration_us(job, params->job_us);
+ if (params->dep_chain && prev)
+ drm_sched_job_add_dependency(&job->base,
+ dma_fence_get(&prev->base.s_fence->finished));
+ drm_mock_sched_job_submit(job);
+ prev = job;
+ }
+
+ done = drm_mock_sched_job_wait_finished(job, HZ);
+ KUNIT_ASSERT_TRUE(test, done);
+
+ for (i = 0; i < params->num_entities; i++)
+ drm_mock_sched_entity_free(entity[i]);
+}
+
+static void drm_sched_basic_entity_cleanup(struct kunit *test)
+{
+ struct drm_mock_sched_job *job, *mid, *prev = NULL;
+ struct drm_mock_scheduler *sched = test->priv;
+ struct drm_mock_sched_entity *entity[4];
+ const unsigned int qd = 100;
+ unsigned int i, cur_ent = 0;
+ bool done;
+
+ /*
+ * Submit a queue of jobs across different entities with an explicit
+ * chain of dependencies between them and trigger entity cleanup while
+ * the queue is still being processed.
+ */
+
+ for (i = 0; i < ARRAY_SIZE(entity); i++)
+ entity[i] = drm_mock_sched_entity_new(test,
+ DRM_SCHED_PRIORITY_NORMAL,
+ sched);
+
+ for (i = 0; i < qd; i++) {
+ job = drm_mock_sched_job_new(test, entity[cur_ent++]);
+ cur_ent %= ARRAY_SIZE(entity);
+ drm_mock_sched_job_set_duration_us(job, 1000);
+ if (prev)
+ drm_sched_job_add_dependency(&job->base,
+ dma_fence_get(&prev->base.s_fence->finished));
+ drm_mock_sched_job_submit(job);
+ if (i == qd / 2)
+ mid = job;
+ prev = job;
+ }
+
+ done = drm_mock_sched_job_wait_finished(mid, HZ);
+ KUNIT_ASSERT_TRUE(test, done);
+
+ /* Exit with half of the queue still pending to be executed. */
+ for (i = 0; i < ARRAY_SIZE(entity); i++)
+ drm_mock_sched_entity_free(entity[i]);
+}
+
+static struct kunit_case drm_sched_basic_tests[] = {
+ KUNIT_CASE(drm_sched_basic_submit),
+ KUNIT_CASE_PARAM(drm_sched_basic_test, drm_sched_basic_gen_params),
+ KUNIT_CASE(drm_sched_basic_entity_cleanup),
+ {}
+};
+
+static struct kunit_suite drm_sched_basic = {
+ .name = "drm_sched_basic_tests",
+ .init = drm_sched_basic_init,
+ .exit = drm_sched_basic_exit,
+ .test_cases = drm_sched_basic_tests,
+};
+
+static void drm_sched_basic_cancel(struct kunit *test)
+{
+ struct drm_mock_sched_entity *entity;
+ struct drm_mock_scheduler *sched;
+ struct drm_mock_sched_job *job;
+ bool done;
+
+ /*
+ * Check that drm_sched_fini() uses the cancel_job() callback to cancel
+ * jobs that are still pending.
+ */
+
+ sched = drm_mock_sched_new(test, MAX_SCHEDULE_TIMEOUT);
+ entity = drm_mock_sched_entity_new(test, DRM_SCHED_PRIORITY_NORMAL,
+ sched);
+
+ job = drm_mock_sched_job_new(test, entity);
+
+ drm_mock_sched_job_submit(job);
+
+ done = drm_mock_sched_job_wait_scheduled(job, HZ);
+ KUNIT_ASSERT_TRUE(test, done);
+
+ drm_mock_sched_entity_free(entity);
+ drm_mock_sched_fini(sched);
+
+ KUNIT_ASSERT_EQ(test, job->hw_fence.error, -ECANCELED);
+}
+
+static struct kunit_case drm_sched_cancel_tests[] = {
+ KUNIT_CASE(drm_sched_basic_cancel),
+ {}
+};
+
+static struct kunit_suite drm_sched_cancel = {
+ .name = "drm_sched_basic_cancel_tests",
+ .init = drm_sched_basic_init,
+ .exit = drm_sched_basic_exit,
+ .test_cases = drm_sched_cancel_tests,
+};
+
+static void drm_sched_basic_timeout(struct kunit *test)
+{
+ struct drm_mock_scheduler *sched = test->priv;
+ struct drm_mock_sched_entity *entity;
+ struct drm_mock_sched_job *job;
+ bool done;
+
+ /*
+ * Submit a single job against a scheduler with the timeout configured
+ * and verify that the timeout handling will run if the backend fails
+ * to complete it in time.
+ */
+
+ entity = drm_mock_sched_entity_new(test,
+ DRM_SCHED_PRIORITY_NORMAL,
+ sched);
+ job = drm_mock_sched_job_new(test, entity);
+
+ drm_mock_sched_job_submit(job);
+
+ done = drm_mock_sched_job_wait_scheduled(job, HZ);
+ KUNIT_ASSERT_TRUE(test, done);
+
+ done = drm_mock_sched_job_wait_finished(job, MOCK_TIMEOUT / 2);
+ KUNIT_ASSERT_FALSE(test, done);
+
+ KUNIT_ASSERT_EQ(test,
+ job->flags & DRM_MOCK_SCHED_JOB_TIMEDOUT,
+ 0);
+
+ done = drm_mock_sched_job_wait_finished(job, MOCK_TIMEOUT);
+ KUNIT_ASSERT_FALSE(test, done);
+
+ KUNIT_ASSERT_EQ(test,
+ job->flags & DRM_MOCK_SCHED_JOB_TIMEDOUT,
+ DRM_MOCK_SCHED_JOB_TIMEDOUT);
+
+ drm_mock_sched_entity_free(entity);
+}
+
+static void drm_sched_skip_reset(struct kunit *test)
+{
+ struct drm_mock_scheduler *sched = test->priv;
+ struct drm_mock_sched_entity *entity;
+ struct drm_mock_sched_job *job;
+ unsigned int i;
+ bool done;
+
+ /*
+ * Submit a single job against a scheduler with the timeout configured
+ * and verify that if the job is still running, the timeout handler
+ * will skip the reset and allow the job to complete.
+ */
+
+ entity = drm_mock_sched_entity_new(test,
+ DRM_SCHED_PRIORITY_NORMAL,
+ sched);
+ job = drm_mock_sched_job_new(test, entity);
+
+ job->flags = DRM_MOCK_SCHED_JOB_DONT_RESET;
+
+ drm_mock_sched_job_submit(job);
+
+ done = drm_mock_sched_job_wait_scheduled(job, HZ);
+ KUNIT_ASSERT_TRUE(test, done);
+
+ done = drm_mock_sched_job_wait_finished(job, 2 * MOCK_TIMEOUT);
+ KUNIT_ASSERT_FALSE(test, done);
+
+ KUNIT_ASSERT_EQ(test,
+ job->flags & DRM_MOCK_SCHED_JOB_RESET_SKIPPED,
+ DRM_MOCK_SCHED_JOB_RESET_SKIPPED);
+
+ i = drm_mock_sched_advance(sched, 1);
+ KUNIT_ASSERT_EQ(test, i, 1);
+
+ done = drm_mock_sched_job_wait_finished(job, HZ);
+ KUNIT_ASSERT_TRUE(test, done);
+
+ drm_mock_sched_entity_free(entity);
+}
+
+static struct kunit_case drm_sched_timeout_tests[] = {
+ KUNIT_CASE(drm_sched_basic_timeout),
+ KUNIT_CASE(drm_sched_skip_reset),
+ {}
+};
+
+static struct kunit_suite drm_sched_timeout = {
+ .name = "drm_sched_basic_timeout_tests",
+ .init = drm_sched_timeout_init,
+ .exit = drm_sched_basic_exit,
+ .test_cases = drm_sched_timeout_tests,
+};
+
+static void drm_sched_priorities(struct kunit *test)
+{
+ struct drm_mock_sched_entity *entity[DRM_SCHED_PRIORITY_COUNT];
+ struct drm_mock_scheduler *sched = test->priv;
+ struct drm_mock_sched_job *job;
+ const unsigned int qd = 100;
+ unsigned int i, cur_ent = 0;
+ enum drm_sched_priority p;
+ bool done;
+
+ /*
+ * Submit a bunch of jobs against entities configured with different
+ * priorities.
+ */
+
+ BUILD_BUG_ON(DRM_SCHED_PRIORITY_KERNEL > DRM_SCHED_PRIORITY_LOW);
+ BUILD_BUG_ON(ARRAY_SIZE(entity) != DRM_SCHED_PRIORITY_COUNT);
+
+ for (p = DRM_SCHED_PRIORITY_KERNEL; p <= DRM_SCHED_PRIORITY_LOW; p++)
+ entity[p] = drm_mock_sched_entity_new(test, p, sched);
+
+ for (i = 0; i < qd; i++) {
+ job = drm_mock_sched_job_new(test, entity[cur_ent++]);
+ cur_ent %= ARRAY_SIZE(entity);
+ drm_mock_sched_job_set_duration_us(job, 1000);
+ drm_mock_sched_job_submit(job);
+ }
+
+ done = drm_mock_sched_job_wait_finished(job, HZ);
+ KUNIT_ASSERT_TRUE(test, done);
+
+ for (i = 0; i < ARRAY_SIZE(entity); i++)
+ drm_mock_sched_entity_free(entity[i]);
+}
+
+static void drm_sched_change_priority(struct kunit *test)
+{
+ struct drm_mock_sched_entity *entity[DRM_SCHED_PRIORITY_COUNT];
+ struct drm_mock_scheduler *sched = test->priv;
+ struct drm_mock_sched_job *job;
+ const unsigned int qd = 1000;
+ unsigned int i, cur_ent = 0;
+ enum drm_sched_priority p;
+
+ /*
+ * Submit a bunch of jobs against entities configured with different
+ * priorities and while waiting for them to complete, periodically keep
+ * changing their priorities.
+ *
+ * We set up the queue-depth (qd) and job duration so the priority
+ * changing loop has some time to interact with submissions to the
+ * backend and job completions as they progress.
+ */
+
+ for (p = DRM_SCHED_PRIORITY_KERNEL; p <= DRM_SCHED_PRIORITY_LOW; p++)
+ entity[p] = drm_mock_sched_entity_new(test, p, sched);
+
+ for (i = 0; i < qd; i++) {
+ job = drm_mock_sched_job_new(test, entity[cur_ent++]);
+ cur_ent %= ARRAY_SIZE(entity);
+ drm_mock_sched_job_set_duration_us(job, 1000);
+ drm_mock_sched_job_submit(job);
+ }
+
+ do {
+ drm_sched_entity_set_priority(&entity[cur_ent]->base,
+ (entity[cur_ent]->base.priority + 1) %
+ DRM_SCHED_PRIORITY_COUNT);
+ cur_ent++;
+ cur_ent %= ARRAY_SIZE(entity);
+ usleep_range(200, 500);
+ } while (!drm_mock_sched_job_is_finished(job));
+
+ for (i = 0; i < ARRAY_SIZE(entity); i++)
+ drm_mock_sched_entity_free(entity[i]);
+}
+
+static struct kunit_case drm_sched_priority_tests[] = {
+ KUNIT_CASE(drm_sched_priorities),
+ KUNIT_CASE(drm_sched_change_priority),
+ {}
+};
+
+static struct kunit_suite drm_sched_priority = {
+ .name = "drm_sched_basic_priority_tests",
+ .init = drm_sched_basic_init,
+ .exit = drm_sched_basic_exit,
+ .test_cases = drm_sched_priority_tests,
+};
+
+static void drm_sched_test_modify_sched(struct kunit *test)
+{
+ unsigned int i, cur_ent = 0, cur_sched = 0;
+ struct drm_mock_sched_entity *entity[13];
+ struct drm_mock_scheduler *sched[3];
+ struct drm_mock_sched_job *job;
+ const unsigned int qd = 1000;
+
+ /*
+ * Submit a bunch of jobs against entities configured with different
+ * schedulers and while waiting for them to complete, periodically keep
+ * changing schedulers associated with each entity.
+ *
+ * We set up the queue-depth (qd) and job duration so the sched modify
+ * loop has some time to interact with submissions to the backend and
+ * job completions as they progress.
+ *
+ * For the number of schedulers and entities we use primes in order to
+ * perturb the entity->sched assignments with less of a regular pattern.
+ */
+
+ for (i = 0; i < ARRAY_SIZE(sched); i++)
+ sched[i] = drm_mock_sched_new(test, MAX_SCHEDULE_TIMEOUT);
+
+ for (i = 0; i < ARRAY_SIZE(entity); i++)
+ entity[i] = drm_mock_sched_entity_new(test,
+ DRM_SCHED_PRIORITY_NORMAL,
+ sched[i % ARRAY_SIZE(sched)]);
+
+ for (i = 0; i < qd; i++) {
+ job = drm_mock_sched_job_new(test, entity[cur_ent++]);
+ cur_ent %= ARRAY_SIZE(entity);
+ drm_mock_sched_job_set_duration_us(job, 1000);
+ drm_mock_sched_job_submit(job);
+ }
+
+ do {
+ struct drm_gpu_scheduler *modify;
+
+ usleep_range(200, 500);
+ cur_ent++;
+ cur_ent %= ARRAY_SIZE(entity);
+ cur_sched++;
+ cur_sched %= ARRAY_SIZE(sched);
+ modify = &sched[cur_sched]->base;
+ drm_sched_entity_modify_sched(&entity[cur_ent]->base, &modify,
+ 1);
+ } while (!drm_mock_sched_job_is_finished(job));
+
+ for (i = 0; i < ARRAY_SIZE(entity); i++)
+ drm_mock_sched_entity_free(entity[i]);
+
+ for (i = 0; i < ARRAY_SIZE(sched); i++)
+ drm_mock_sched_fini(sched[i]);
+}
+
+static struct kunit_case drm_sched_modify_sched_tests[] = {
+ KUNIT_CASE(drm_sched_test_modify_sched),
+ {}
+};
+
+static struct kunit_suite drm_sched_modify_sched = {
+ .name = "drm_sched_basic_modify_sched_tests",
+ .test_cases = drm_sched_modify_sched_tests,
+};
+
+static void drm_sched_test_credits(struct kunit *test)
+{
+ struct drm_mock_sched_entity *entity;
+ struct drm_mock_scheduler *sched;
+ struct drm_mock_sched_job *job[2];
+ bool done;
+ int i;
+
+ /*
+ * Check that the configured credit limit is respected.
+ */
+
+ sched = drm_mock_sched_new(test, MAX_SCHEDULE_TIMEOUT);
+ sched->base.credit_limit = 1;
+
+ entity = drm_mock_sched_entity_new(test,
+ DRM_SCHED_PRIORITY_NORMAL,
+ sched);
+
+ job[0] = drm_mock_sched_job_new(test, entity);
+ job[1] = drm_mock_sched_job_new(test, entity);
+
+ drm_mock_sched_job_submit(job[0]);
+ drm_mock_sched_job_submit(job[1]);
+
+ done = drm_mock_sched_job_wait_scheduled(job[0], HZ);
+ KUNIT_ASSERT_TRUE(test, done);
+
+ done = drm_mock_sched_job_wait_scheduled(job[1], HZ);
+ KUNIT_ASSERT_FALSE(test, done);
+
+ i = drm_mock_sched_advance(sched, 1);
+ KUNIT_ASSERT_EQ(test, i, 1);
+
+ done = drm_mock_sched_job_wait_scheduled(job[1], HZ);
+ KUNIT_ASSERT_TRUE(test, done);
+
+ i = drm_mock_sched_advance(sched, 1);
+ KUNIT_ASSERT_EQ(test, i, 1);
+
+ done = drm_mock_sched_job_wait_finished(job[1], HZ);
+ KUNIT_ASSERT_TRUE(test, done);
+
+ drm_mock_sched_entity_free(entity);
+ drm_mock_sched_fini(sched);
+}
+
+static struct kunit_case drm_sched_credits_tests[] = {
+ KUNIT_CASE(drm_sched_test_credits),
+ {}
+};
+
+static struct kunit_suite drm_sched_credits = {
+ .name = "drm_sched_basic_credits_tests",
+ .test_cases = drm_sched_credits_tests,
+};
+
+kunit_test_suites(&drm_sched_basic,
+ &drm_sched_timeout,
+ &drm_sched_cancel,
+ &drm_sched_priority,
+ &drm_sched_modify_sched,
+ &drm_sched_credits);