drm/i915: Prevent use of global_seqno=0

We are not allowed to assign rq->global_seqno=0 as it has a special
meaning of "inactive" (not executing on HW).

Fixes: 6faf5916e6 ("drm/i915: Remove HW semaphores for gen7 inter-engine synchronisation")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190119143024.26971-1-chris@chris-wilson.co.uk
This commit is contained in:
Chris Wilson 2019-01-19 14:30:24 +00:00
parent d25236a329
commit f1e9c90947

View File

@ -343,6 +343,13 @@ static void move_to_timeline(struct i915_request *request,
spin_unlock(&request->timeline->lock); spin_unlock(&request->timeline->lock);
} }
static u32 next_global_seqno(struct i915_timeline *tl)
{
if (!++tl->seqno)
++tl->seqno;
return tl->seqno;
}
void __i915_request_submit(struct i915_request *request) void __i915_request_submit(struct i915_request *request)
{ {
struct intel_engine_cs *engine = request->engine; struct intel_engine_cs *engine = request->engine;
@ -359,7 +366,7 @@ void __i915_request_submit(struct i915_request *request)
GEM_BUG_ON(request->global_seqno); GEM_BUG_ON(request->global_seqno);
seqno = timeline_get_seqno(&engine->timeline); seqno = next_global_seqno(&engine->timeline);
GEM_BUG_ON(!seqno); GEM_BUG_ON(!seqno);
GEM_BUG_ON(intel_engine_signaled(engine, seqno)); GEM_BUG_ON(intel_engine_signaled(engine, seqno));