Modifying a remote context requires careful serialisation with requests on that context, and that serialisation requires us to take their timeline->mutex. Make it so.
Note that while struct_mutex rules, we can't create more than one request in parallel, but that age is soon coming to an end. v2: Though it doesn't affect the current users, contexts may share timelines so check if we already hold the right mutex. Signed-off-by: Chris Wilson <[email protected]> Cc: Tvrtko Ursulin <[email protected]> --- drivers/gpu/drm/i915/gt/intel_context.c | 17 +++++++++++++++-- 1 file changed, 15 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/gt/intel_context.c b/drivers/gpu/drm/i915/gt/intel_context.c index 87c84cc0f658..fe995a797452 100644 --- a/drivers/gpu/drm/i915/gt/intel_context.c +++ b/drivers/gpu/drm/i915/gt/intel_context.c @@ -260,10 +260,18 @@ int intel_context_prepare_remote_request(struct intel_context *ce, /* Only suitable for use in remotely modifying this context */ GEM_BUG_ON(rq->hw_context == ce); + if (rq->timeline != tl) { /* beware timeline sharing */ + err = mutex_lock_interruptible_nested(&tl->mutex, + SINGLE_DEPTH_NESTING); + if (err) + return err; + } + lockdep_assert_held(&tl->mutex); + /* Queue this switch after all other activity by this context. */ err = i915_active_request_set(&tl->last_request, rq); if (err) - return err; + goto unlock; /* * Guarantee context image and the timeline remains pinned until the @@ -273,7 +281,12 @@ int intel_context_prepare_remote_request(struct intel_context *ce, * words transfer the pinned ce object to tracked active request. */ GEM_BUG_ON(i915_active_is_idle(&ce->active)); - return i915_active_ref(&ce->active, rq->fence.context, rq); + err = i915_active_ref(&ce->active, rq->fence.context, rq); + +unlock: + if (rq->timeline != tl) + mutex_unlock(&tl->mutex); + return err; } struct i915_request *intel_context_create_request(struct intel_context *ce) -- 2.22.0 _______________________________________________ Intel-gfx mailing list [email protected] https://lists.freedesktop.org/mailman/listinfo/intel-gfx
