From 5f8f635edd8ad5a6416bff4c5ff486500357f473 Mon Sep 17 00:00:00 2001 From: Jerome Glisse Date: Mon, 17 Dec 2012 11:04:32 -0500 Subject: drm/radeon: avoid deadlock in pm path when waiting for fence MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit radeon_fence_wait_empty_locked should not trigger GPU reset as no place where it's call from would benefit from such thing and it actually lead to a kernel deadlock in case the reset is triggered from pm codepath. Instead force ring completion in place where it makes sense or return early in others. Signed-off-by: Jerome Glisse Reviewed-by: Christian König Signed-off-by: Alex Deucher Cc: stable@vger.kernel.org --- drivers/gpu/drm/radeon/radeon_fence.c | 30 ++++++++++++++---------------- 1 file changed, 14 insertions(+), 16 deletions(-) (limited to 'drivers/gpu/drm/radeon/radeon_fence.c') diff --git a/drivers/gpu/drm/radeon/radeon_fence.c b/drivers/gpu/drm/radeon/radeon_fence.c index a9b0fa5608e..34356252567 100644 --- a/drivers/gpu/drm/radeon/radeon_fence.c +++ b/drivers/gpu/drm/radeon/radeon_fence.c @@ -609,26 +609,20 @@ int radeon_fence_wait_next_locked(struct radeon_device *rdev, int ring) * Returns 0 if the fences have passed, error for all other cases. * Caller must hold ring lock. */ -void radeon_fence_wait_empty_locked(struct radeon_device *rdev, int ring) +int radeon_fence_wait_empty_locked(struct radeon_device *rdev, int ring) { uint64_t seq = rdev->fence_drv[ring].sync_seq[ring]; + int r; - while(1) { - int r; - r = radeon_fence_wait_seq(rdev, seq, ring, false, false); + r = radeon_fence_wait_seq(rdev, seq, ring, false, false); + if (r) { if (r == -EDEADLK) { - mutex_unlock(&rdev->ring_lock); - r = radeon_gpu_reset(rdev); - mutex_lock(&rdev->ring_lock); - if (!r) - continue; - } - if (r) { - dev_err(rdev->dev, "error waiting for ring to become" - " idle (%d)\n", r); + return -EDEADLK; } - return; + dev_err(rdev->dev, "error waiting for ring[%d] to become idle (%d)\n", + ring, r); } + return 0; } /** @@ -854,13 +848,17 @@ int radeon_fence_driver_init(struct radeon_device *rdev) */ void radeon_fence_driver_fini(struct radeon_device *rdev) { - int ring; + int ring, r; mutex_lock(&rdev->ring_lock); for (ring = 0; ring < RADEON_NUM_RINGS; ring++) { if (!rdev->fence_drv[ring].initialized) continue; - radeon_fence_wait_empty_locked(rdev, ring); + r = radeon_fence_wait_empty_locked(rdev, ring); + if (r) { + /* no need to trigger GPU reset as we are unloading */ + radeon_fence_driver_force_completion(rdev); + } wake_up_all(&rdev->fence_queue); radeon_scratch_free(rdev, rdev->fence_drv[ring].scratch_reg); rdev->fence_drv[ring].initialized = false; -- cgit v1.2.3