From: Chris Wilson Date: Tue, 24 Oct 2017 23:08:54 +0100 Subject: drm/i915/selftests: Don't try to queue a request with zero delay Git-commit: b1f9107e1b251b2cbd413062fad3636570d2ea20 Patch-mainline: v4.16-rc1 References: FATE#326289 FATE#326079 FATE#326049 FATE#322398 FATE#326166 Instead of trying to create a timer with zero delay (i.e. with expires set to the current jiffies and not the future, an already expired timer), execute that request immediately. v2: Refactor list_del_init+signal into its own little function. v3: Reorder testing so as not to immediately signal a delayed request. Signed-off-by: Chris Wilson Link: https://patchwork.freedesktop.org/patch/msgid/20171024220855.30155-1-chris@chris-wilson.co.uk Cc: Joonas Lahtinen Reviewed-by: Joonas Lahtinen Acked-by: Petr Tesarik --- drivers/gpu/drm/i915/selftests/mock_engine.c | 37 ++++++++++++++++++++------- 1 file changed, 28 insertions(+), 9 deletions(-) --- a/drivers/gpu/drm/i915/selftests/mock_engine.c +++ b/drivers/gpu/drm/i915/selftests/mock_engine.c @@ -32,6 +32,13 @@ static struct mock_request *first_reques link); } +static void advance(struct mock_engine *engine, + struct mock_request *request) +{ + list_del_init(&request->link); + mock_seqno_advance(&engine->base, request->base.global_seqno); +} + static void hw_delay_complete(struct timer_list *t) { struct mock_engine *engine = from_timer(engine, t, hw_delay); @@ -39,15 +46,23 @@ static void hw_delay_complete(struct tim spin_lock(&engine->hw_lock); - request = first_request(engine); - if (request) { - list_del_init(&request->link); - mock_seqno_advance(&engine->base, request->base.global_seqno); - } - + /* Timer fired, first request is complete */ request = first_request(engine); if (request) - mod_timer(&engine->hw_delay, jiffies + request->delay); + advance(engine, request); + + /* + * Also immediately signal any subsequent 0-delay requests, but + * requeue the timer for the next delayed request. + */ + while ((request = first_request(engine))) { + if (request->delay) { + mod_timer(&engine->hw_delay, jiffies + request->delay); + break; + } + + advance(engine, request); + } spin_unlock(&engine->hw_lock); } @@ -98,8 +113,12 @@ static void mock_submit_request(struct d spin_lock_irq(&engine->hw_lock); list_add_tail(&mock->link, &engine->hw_queue); - if (mock->link.prev == &engine->hw_queue) - mod_timer(&engine->hw_delay, jiffies + mock->delay); + if (mock->link.prev == &engine->hw_queue) { + if (mock->delay) + mod_timer(&engine->hw_delay, jiffies + mock->delay); + else + advance(engine, mock); + } spin_unlock_irq(&engine->hw_lock); }