Commit a4d362bb authored by Matthew Auld's avatar Matthew Auld Committed by Rodrigo Vivi
Browse files

drm/xe/ct: serialise fast_lock during CT disable 



The fast-path CT could be running as we enter a runtime-suspend or
potentially a GT reset, however here we only use the ct->fast_lock and
not the full ct->lock. Before disabling the CT, also serialise against
the fast_lock to ensure any in-progress work finishes before we start
nuking the CT related stuff. Once we disable ct->enabled and drop the
lock, any new work should fail gracefully, and anything that was in
progress should be finished.

Signed-off-by: default avatarMatthew Auld <matthew.auld@intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: José Roberto de Souza <jose.souza@intel.com>
Reviewed-by: default avatarMatthew Brost <matthew.brost@intel.com>
Signed-off-by: default avatarRodrigo Vivi <rodrigo.vivi@intel.com>
parent 4803f6e2

drivers/gpu/drm/xe/xe_guc_ct.c

+6 −2
Original line number Diff line number Diff line
@@ -301,8 +301,10 @@ int xe_guc_ct_enable(struct xe_guc_ct *ct) 
		goto err_out;



	mutex_lock(&ct->lock);

	spin_lock_irq(&ct->fast_lock);

	ct->g2h_outstanding = 0;

	ct->enabled = true;

	spin_unlock_irq(&ct->fast_lock);

	mutex_unlock(&ct->lock);



	smp_mb();
@@ -319,8 +321,10 @@ int xe_guc_ct_enable(struct xe_guc_ct *ct) 


void xe_guc_ct_disable(struct xe_guc_ct *ct)

{

	mutex_lock(&ct->lock);

	ct->enabled = false;

	mutex_lock(&ct->lock); /* Serialise dequeue_one_g2h() */

	spin_lock_irq(&ct->fast_lock); /* Serialise CT fast-path */

	ct->enabled = false; /* Finally disable CT communication */

	spin_unlock_irq(&ct->fast_lock);

	mutex_unlock(&ct->lock);



	xa_destroy(&ct->fence_lookup);