From: Weinan Li Date: Wed, 27 Feb 2019 07:36:58 +0000 (+0800) Subject: drm/i915/gvt: stop scheduling workload when vgpu is inactive X-Git-Tag: v5.1-rc3~29^2^2~4^2~3 X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=9f4984773240cf004cbffb99316af3269bbb5e26;p=linux.git drm/i915/gvt: stop scheduling workload when vgpu is inactive There is one corner case that workload_thread may pick and dispatch one workload of vgpu after it's already deactivated. Below is the scenario: 1. deactive_vgpu got the vgpu_lock, it found pending workload was submitted, then it released the vgpu_lock and wait for vgpu idle. 2. before deactive_vgpu got the vgpu_lock back, workload_thread might pick one new valid workload, then it was blocked by the vgpu_lock. 3. deactive_vgpu got the vgpu_lock again, finished the last processes of deactivating, then release the vgpu_lock. 4. workload_thread got the vgpu_lock, then it will try to dispatch the fetched workload. It's not expected one workload of deactivated vgpu is dispatched. The solution is to add condition check of the vgpu's active flag and stop to schedule when it's inactive. Reviewed-by: Zhenyu Wang Signed-off-by: Weinan Li Signed-off-by: Zhenyu Wang --- diff --git a/drivers/gpu/drm/i915/gvt/scheduler.c b/drivers/gpu/drm/i915/gvt/scheduler.c index 55bb7885e228..af97df10495e 100644 --- a/drivers/gpu/drm/i915/gvt/scheduler.c +++ b/drivers/gpu/drm/i915/gvt/scheduler.c @@ -738,7 +738,8 @@ static struct intel_vgpu_workload *pick_next_workload( goto out; } - if (list_empty(workload_q_head(scheduler->current_vgpu, ring_id))) + if (!scheduler->current_vgpu->active || + list_empty(workload_q_head(scheduler->current_vgpu, ring_id))) goto out; /*