From badf1f2724d430c8a310be549b49f8333817dbeb Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Fri, 5 Jul 2019 08:45:57 +0100 Subject: [PATCH] drm/i915: Order assert forcewake test Read the current value before computing the expected to ensure that if the timer does complete early (against our will), it should not cause a false positive. v2: The local irq disable did not prevent the timer from running. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=111074 Signed-off-by: Chris Wilson Cc: Tvrtko Ursulin Reviewed-by: Tvrtko Ursulin Link: https://patchwork.freedesktop.org/patch/msgid/20190705074604.16496-1-chris@chris-wilson.co.uk --- drivers/gpu/drm/i915/intel_uncore.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_uncore.c b/drivers/gpu/drm/i915/intel_uncore.c index 2042c94c9cc9..bb9e0da30e94 100644 --- a/drivers/gpu/drm/i915/intel_uncore.c +++ b/drivers/gpu/drm/i915/intel_uncore.c @@ -758,19 +758,18 @@ void assert_forcewakes_active(struct intel_uncore *uncore, * Check that the caller has an explicit wakeref and we don't mistake * it for the auto wakeref. */ - local_irq_disable(); for_each_fw_domain_masked(domain, fw_domains, uncore, tmp) { + unsigned int actual = READ_ONCE(domain->wake_count); unsigned int expect = 1; if (hrtimer_active(&domain->timer) && READ_ONCE(domain->active)) expect++; /* pending automatic release */ - if (WARN(domain->wake_count < expect, + if (WARN(actual < expect, "Expected domain %d to be held awake by caller, count=%d\n", - domain->id, domain->wake_count)) + domain->id, actual)) break; } - local_irq_enable(); } /* We give fast paths for the really cool registers */ -- GitLab