[PATCH 03/11] drm/i915/display: convert inner wakeref get towards get_if_in_use

Rodrigo Vivi rodrigo.vivi at intel.com
Mon Mar 11 19:22:55 UTC 2024


This patch brings no functional change. Since at this point of
the code we are already asserting a wakeref was held, it means
that we are with runtime_pm 'in_use' and in practical terms we
are only bumping the pm_runtime usage counter and moving on.

However, xe driver has a lockdep annotation that warned us that
if a sync resume was actually called at this point, we could have
a deadlock because we are inside the power_domains->lock locked
area and the resume would call the irq_reset, which would also
try to get the power_domains->lock.

For this reason, let's convert this call to a safer option and
calm lockdep on.

v2: use _noresume variant instead of get_in_use (Ville, Imre)

Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
Acked-by: Imre Deak <imre.deak at intel.com>
Cc: Matthew Auld <matthew.auld at intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi at intel.com>
---
 drivers/gpu/drm/i915/display/intel_display_power.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/display/intel_display_power.c b/drivers/gpu/drm/i915/display/intel_display_power.c
index 6fd4fa52253a..048943d0a881 100644
--- a/drivers/gpu/drm/i915/display/intel_display_power.c
+++ b/drivers/gpu/drm/i915/display/intel_display_power.c
@@ -646,7 +646,7 @@ release_async_put_domains(struct i915_power_domains *power_domains,
 	 * power well disabling.
 	 */
 	assert_rpm_raw_wakeref_held(rpm);
-	wakeref = intel_runtime_pm_get(rpm);
+	wakeref = intel_runtime_pm_get_noresume(rpm);
 
 	for_each_power_domain(domain, mask) {
 		/* Clear before put, so put's sanity check is happy. */
-- 
2.44.0



More information about the Intel-gfx mailing list