On Fri, Aug 13, 2010 at 10:53 AM, Alex Deucher alexdeucher@gmail.com wrote:

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

Also fixes: https://bugs.freedesktop.org/show_bug.cgi?id=29384

Alex

Signed-off-by: Alex Deucher alexdeucher@gmail.com Cc: stable@kernel.org

---

drivers/gpu/drm/radeon/radeon_pm.c |    5 +++++  1 files changed, 5 insertions(+), 0 deletions(-)

diff --git a/drivers/gpu/drm/radeon/radeon_pm.c b/drivers/gpu/drm/radeon/radeon_pm.c index a3d25f4..9a8031b 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); -- 1.7.1.1