Am Dienstag, den 05.06.2018, 12:03 -0700 schrieb Eric Anholt:
Between creation and queueing of a job, you need to prevent any other job from being created and queued. Otherwise the scheduler's fences may be signaled out of seqno order.
Signed-off-by: Eric Anholt eric@anholt.net
Fixes: 57692c94dcbe ("drm/v3d: Introduce a new DRM driver for Broadcom V3D V3.x+")
ccing amd-gfx due to interaction of this series with the scheduler.
drivers/gpu/drm/v3d/v3d_drv.h | 5 +++++ drivers/gpu/drm/v3d/v3d_gem.c | 11 +++++++++-- 2 files changed, 14 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/v3d/v3d_drv.h b/drivers/gpu/drm/v3d/v3d_drv.h index a043ac3aae98..26005abd9c5d 100644 --- a/drivers/gpu/drm/v3d/v3d_drv.h +++ b/drivers/gpu/drm/v3d/v3d_drv.h @@ -85,6 +85,11 @@ struct v3d_dev {
*/ struct mutex reset_lock;
- /* Lock taken when creating and pushing the GPU scheduler
- * jobs, to keep the sched-fence seqnos in order.
- */
- struct mutex sched_lock;
struct { u32 num_allocated; u32 pages_allocated;
diff --git a/drivers/gpu/drm/v3d/v3d_gem.c b/drivers/gpu/drm/v3d/v3d_gem.c index b513f9189caf..9ea83bdb9a30 100644 --- a/drivers/gpu/drm/v3d/v3d_gem.c +++ b/drivers/gpu/drm/v3d/v3d_gem.c @@ -550,13 +550,16 @@ v3d_submit_cl_ioctl(struct drm_device *dev, void *data,
if (ret) goto fail;
- mutex_lock(&v3d->sched_lock);
if (exec->bin.start != exec->bin.end) { ret = drm_sched_job_init(&exec->bin.base, &v3d->queue[V3D_BIN].sched, &v3d_priv->sched_entity[V3D_BIN], v3d_priv);
if (ret)
if (ret) {mutex_unlock(&v3d->sched_lock);goto fail_unreserve;
I don't see any path where you would go to fail_unreserve with the mutex not yet locked, so you could just fold the mutex_unlock into this error path for a bit less code duplication.
Otherwise this looks fine.
Regards, Lucas
}exec->bin_done_fence = dma_fence_get(&exec->bin.base.s_fence->finished);
@@ -570,12 +573,15 @@ v3d_submit_cl_ioctl(struct drm_device *dev, void *data,
&v3d->queue[V3D_RENDER].sched, &v3d_priv->sched_entity[V3D_RENDER], v3d_priv);
- if (ret)
- if (ret) {
mutex_unlock(&v3d->sched_lock);goto fail_unreserve;
- }
kref_get(&exec->refcount); /* put by scheduler job completion */ drm_sched_entity_push_job(&exec->render.base, &v3d_priv->sched_entity[V3D_RENDER]);
- mutex_unlock(&v3d->sched_lock);
v3d_attach_object_fences(exec);
@@ -615,6 +621,7 @@ v3d_gem_init(struct drm_device *dev)
spin_lock_init(&v3d->job_lock); mutex_init(&v3d->bo_lock); mutex_init(&v3d->reset_lock);
- mutex_init(&v3d->sched_lock);
/* Note: We don't allocate address 0. Various bits of HW * treat 0 as special, such as the occlusion query counters