| Message ID | 20240905071914.3278599-1-boris.brezillon@collabora.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm/panthor: Don't declare a queue blocked if deferred operations are pending | expand |
On 05/09/2024 08:19, Boris Brezillon wrote: > If deferred operations are pending, we want to wait for those to > land before declaring the queue blocked on a SYNC_WAIT. We need > this to deal with the case where the sync object is signalled through > a deferred SYNC_{ADD,SET} from the same queue. If we don't do that > and the group gets scheduled out before the deferred SYNC_{SET,ADD} > is executed, we'll end up with a timeout, because no external > SYNC_{SET,ADD} will make the scheduler reconsider the group for > execution. > > Fixes: de8548813824 ("drm/panthor: Add the scheduler logical block") > Cc: <stable@vger.kernel.org> > Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com> Reviewed-by: Steven Price <steven.price@arm.com> > --- > drivers/gpu/drm/panthor/panthor_sched.c | 8 +++++++- > 1 file changed, 7 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/panthor/panthor_sched.c b/drivers/gpu/drm/panthor/panthor_sched.c > index 41260cf4beb8..201d5e7a921e 100644 > --- a/drivers/gpu/drm/panthor/panthor_sched.c > +++ b/drivers/gpu/drm/panthor/panthor_sched.c > @@ -1103,7 +1103,13 @@ cs_slot_sync_queue_state_locked(struct panthor_device *ptdev, u32 csg_id, u32 cs > list_move_tail(&group->wait_node, > &group->ptdev->scheduler->groups.waiting); > } > - group->blocked_queues |= BIT(cs_id); > + > + /* The queue is only blocked if there's no deferred operation > + * pending, which can be checked through the scoreboard status. > + */ > + if (!cs_iface->output->status_scoreboards) > + group->blocked_queues |= BIT(cs_id); > + > queue->syncwait.gpu_va = cs_iface->output->status_wait_sync_ptr; > queue->syncwait.ref = cs_iface->output->status_wait_sync_value; > status_wait_cond = cs_iface->output->status_wait & CS_STATUS_WAIT_SYNC_COND_MASK;
On Thu, Sep 05, 2024 at 09:19:14AM +0200, Boris Brezillon wrote: > If deferred operations are pending, we want to wait for those to > land before declaring the queue blocked on a SYNC_WAIT. We need > this to deal with the case where the sync object is signalled through > a deferred SYNC_{ADD,SET} from the same queue. If we don't do that > and the group gets scheduled out before the deferred SYNC_{SET,ADD} > is executed, we'll end up with a timeout, because no external > SYNC_{SET,ADD} will make the scheduler reconsider the group for > execution. > > Fixes: de8548813824 ("drm/panthor: Add the scheduler logical block") > Cc: <stable@vger.kernel.org> > Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com> Reviewed-by: Liviu Dudau <liviu.dudau@arm.com> Best regards, Liviu > --- > drivers/gpu/drm/panthor/panthor_sched.c | 8 +++++++- > 1 file changed, 7 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/panthor/panthor_sched.c b/drivers/gpu/drm/panthor/panthor_sched.c > index 41260cf4beb8..201d5e7a921e 100644 > --- a/drivers/gpu/drm/panthor/panthor_sched.c > +++ b/drivers/gpu/drm/panthor/panthor_sched.c > @@ -1103,7 +1103,13 @@ cs_slot_sync_queue_state_locked(struct panthor_device *ptdev, u32 csg_id, u32 cs > list_move_tail(&group->wait_node, > &group->ptdev->scheduler->groups.waiting); > } > - group->blocked_queues |= BIT(cs_id); > + > + /* The queue is only blocked if there's no deferred operation > + * pending, which can be checked through the scoreboard status. > + */ > + if (!cs_iface->output->status_scoreboards) > + group->blocked_queues |= BIT(cs_id); > + > queue->syncwait.gpu_va = cs_iface->output->status_wait_sync_ptr; > queue->syncwait.ref = cs_iface->output->status_wait_sync_value; > status_wait_cond = cs_iface->output->status_wait & CS_STATUS_WAIT_SYNC_COND_MASK; > -- > 2.46.0 >
diff --git a/drivers/gpu/drm/panthor/panthor_sched.c b/drivers/gpu/drm/panthor/panthor_sched.c index 41260cf4beb8..201d5e7a921e 100644 --- a/drivers/gpu/drm/panthor/panthor_sched.c +++ b/drivers/gpu/drm/panthor/panthor_sched.c @@ -1103,7 +1103,13 @@ cs_slot_sync_queue_state_locked(struct panthor_device *ptdev, u32 csg_id, u32 cs list_move_tail(&group->wait_node, &group->ptdev->scheduler->groups.waiting); } - group->blocked_queues |= BIT(cs_id); + + /* The queue is only blocked if there's no deferred operation + * pending, which can be checked through the scoreboard status. + */ + if (!cs_iface->output->status_scoreboards) + group->blocked_queues |= BIT(cs_id); + queue->syncwait.gpu_va = cs_iface->output->status_wait_sync_ptr; queue->syncwait.ref = cs_iface->output->status_wait_sync_value; status_wait_cond = cs_iface->output->status_wait & CS_STATUS_WAIT_SYNC_COND_MASK;
If deferred operations are pending, we want to wait for those to land before declaring the queue blocked on a SYNC_WAIT. We need this to deal with the case where the sync object is signalled through a deferred SYNC_{ADD,SET} from the same queue. If we don't do that and the group gets scheduled out before the deferred SYNC_{SET,ADD} is executed, we'll end up with a timeout, because no external SYNC_{SET,ADD} will make the scheduler reconsider the group for execution. Fixes: de8548813824 ("drm/panthor: Add the scheduler logical block") Cc: <stable@vger.kernel.org> Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com> --- drivers/gpu/drm/panthor/panthor_sched.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-)