From 5db1d4ea91b6ee447c4ae01f7f56803e32e690b1 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Mon, 4 Jun 2018 08:34:40 +0100 Subject: [PATCH] drm/i915/execlists: Push the tasklet kick after reset to reset_finish In the unlikely case where we have failed to keep submitting to the GPU, we end up with the ELSP queue empty but a pending queue of requests. Here, we skip the per-engine reset as there is no guilty request, but in doing so we also skip the engine restart leaving ourselves with a permanently hung engine. A quick way to recover is by moving the tasklet kick to execlists_reset_finish() (from init_hw). We still emit the error on hanging, so the error is not lost but we should be able to recover. Signed-off-by: Chris Wilson Cc: Mika Kuoppala Cc: Tvrtko Ursulin Cc: Michel Thierry Link: https://patchwork.freedesktop.org/patch/msgid/20180604073441.6737-2-chris@chris-wilson.co.uk Reviewed-by: Mika Kuoppala --- drivers/gpu/drm/i915/intel_lrc.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c index 44e4c9e07571..8d56bcb00979 100644 --- a/drivers/gpu/drm/i915/intel_lrc.c +++ b/drivers/gpu/drm/i915/intel_lrc.c @@ -1811,7 +1811,6 @@ static bool unexpected_starting_state(struct intel_engine_cs *engine) static int gen8_init_common_ring(struct intel_engine_cs *engine) { - struct intel_engine_execlists * const execlists = &engine->execlists; int ret; ret = intel_mocs_init_engine(engine); @@ -1829,10 +1828,6 @@ static int gen8_init_common_ring(struct intel_engine_cs *engine) enable_execlists(engine); - /* After a GPU reset, we may have requests to replay */ - if (execlists->first) - tasklet_schedule(&execlists->tasklet); - return 0; } @@ -2015,6 +2010,12 @@ static void execlists_reset(struct intel_engine_cs *engine, static void execlists_reset_finish(struct intel_engine_cs *engine) { + struct intel_engine_execlists * const execlists = &engine->execlists; + + /* After a GPU reset, we may have requests to replay */ + if (execlists->first) + tasklet_schedule(&execlists->tasklet); + /* * Flush the tasklet while we still have the forcewake to be sure * that it is not allowed to sleep before we restart and reload a @@ -2024,7 +2025,7 @@ static void execlists_reset_finish(struct intel_engine_cs *engine) * serialising multiple attempts to reset so that we know that we * are the only one manipulating tasklet state. */ - __tasklet_enable_sync_once(&engine->execlists.tasklet); + __tasklet_enable_sync_once(&execlists->tasklet); GEM_TRACE("%s\n", engine->name); }