From 4e186b2d6c878793587c35d7f06c94565d76e9b8 Mon Sep 17 00:00:00 2001 From: Alex Deucher Date: Fri, 13 Aug 2010 10:53:35 -0400 Subject: [PATCH] drm/radeon/kms/pm: bail early if nothing's changing If we aren't changing the power state, no need to take locks and schedule fences, etc. There seem to be lock ordering issues in the CP and fence code in some cases; see bug 29140 below. Fixes: https://bugs.freedesktop.org/show_bug.cgi?id=29140 Possibly also: https://bugzilla.kernel.org/show_bug.cgi?id=16581 Signed-off-by: Alex Deucher Cc: stable@kernel.org Signed-off-by: Dave Airlie --- drivers/gpu/drm/radeon/radeon_pm.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/gpu/drm/radeon/radeon_pm.c b/drivers/gpu/drm/radeon/radeon_pm.c index 58038f5c..477ba67 100644 --- a/drivers/gpu/drm/radeon/radeon_pm.c +++ b/drivers/gpu/drm/radeon/radeon_pm.c @@ -226,6 +226,11 @@ static void radeon_pm_set_clocks(struct radeon_device *rdev) { int i; + /* no need to take locks, etc. if nothing's going to change */ + if ((rdev->pm.requested_clock_mode_index == rdev->pm.current_clock_mode_index) && + (rdev->pm.requested_power_state_index == rdev->pm.current_power_state_index)) + return; + mutex_lock(&rdev->ddev->struct_mutex); mutex_lock(&rdev->vram_mutex); mutex_lock(&rdev->cp.mutex); -- 2.7.4