tasklet_kill() ensures that we _yield_ the processor until a remote tasklet is completed. However, this leads to a starvation condition as being at the bottom of the scheduler's runqueue means that anything else is able to run, including all hogs keeping the tasklet occupied.
Signed-off-by: Chris Wilson <ch...@chris-wilson.co.uk> --- drivers/gpu/drm/i915/gt/intel_engine_cs.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/i915/gt/intel_engine_cs.c b/drivers/gpu/drm/i915/gt/intel_engine_cs.c index e3bda3509cd0..5c08c29e58af 100644 --- a/drivers/gpu/drm/i915/gt/intel_engine_cs.c +++ b/drivers/gpu/drm/i915/gt/intel_engine_cs.c @@ -1197,10 +1197,6 @@ void intel_engine_flush_submission(struct intel_engine_cs *engine) if (!t->func) return; - /* Synchronise and wait for the tasklet on another CPU */ - tasklet_kill(t); - - /* Having cancelled the tasklet, ensure that is run */ local_bh_disable(); if (tasklet_trylock(t)) { /* Must wait for any GPU reset in progress. */ @@ -1209,6 +1205,9 @@ void intel_engine_flush_submission(struct intel_engine_cs *engine) tasklet_unlock(t); } local_bh_enable(); + + /* Synchronise and wait for the tasklet on another CPU */ + tasklet_unlock_wait(t); } /** -- 2.20.1 _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx