From 8a47cc9ec1249eefd600adb273148c62879a560d Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Christian=20K=C3=B6nig?= Date: Wed, 9 May 2012 15:34:48 +0200 Subject: drm/radeon: rework locking ring emission mutex in fence deadlock detection v2 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Some callers illegal called fence_wait_next/empty while holding the ring emission mutex. So don't relock the mutex in that cases, and move the actual locking into the fence code. v2: Don't try to unlock the mutex if it isn't locked. Signed-off-by: Christian König Signed-off-by: Dave Airlie --- drivers/gpu/drm/radeon/radeon_fence.c | 43 +++++++++++++++++++++++------------ 1 file changed, 29 insertions(+), 14 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 ed202255ac76..098d1faed1a6 100644 --- a/drivers/gpu/drm/radeon/radeon_fence.c +++ b/drivers/gpu/drm/radeon/radeon_fence.c @@ -194,7 +194,7 @@ bool radeon_fence_signaled(struct radeon_fence *fence) } static int radeon_fence_wait_seq(struct radeon_device *rdev, u64 target_seq, - unsigned ring, bool intr) + unsigned ring, bool intr, bool lock_ring) { unsigned long timeout, last_activity; uint64_t seq; @@ -249,8 +249,16 @@ static int radeon_fence_wait_seq(struct radeon_device *rdev, u64 target_seq, if (seq != atomic64_read(&rdev->fence_drv[ring].last_seq)) { continue; } + + if (lock_ring) { + mutex_lock(&rdev->ring_lock); + } + /* test if somebody else has already decided that this is a lockup */ if (last_activity != rdev->fence_drv[ring].last_activity) { + if (lock_ring) { + mutex_unlock(&rdev->ring_lock); + } continue; } @@ -264,15 +272,17 @@ static int radeon_fence_wait_seq(struct radeon_device *rdev, u64 target_seq, rdev->fence_drv[i].last_activity = jiffies; } - /* change last activity so nobody else think there is a lockup */ - for (i = 0; i < RADEON_NUM_RINGS; ++i) { - rdev->fence_drv[i].last_activity = jiffies; - } - /* mark the ring as not ready any more */ rdev->ring[ring].ready = false; + if (lock_ring) { + mutex_unlock(&rdev->ring_lock); + } return -EDEADLK; } + + if (lock_ring) { + mutex_unlock(&rdev->ring_lock); + } } } return 0; @@ -287,7 +297,8 @@ int radeon_fence_wait(struct radeon_fence *fence, bool intr) return -EINVAL; } - r = radeon_fence_wait_seq(fence->rdev, fence->seq, fence->ring, intr); + r = radeon_fence_wait_seq(fence->rdev, fence->seq, + fence->ring, intr, true); if (r) { return r; } @@ -295,7 +306,7 @@ int radeon_fence_wait(struct radeon_fence *fence, bool intr) return 0; } -int radeon_fence_wait_next(struct radeon_device *rdev, int ring) +int radeon_fence_wait_next_locked(struct radeon_device *rdev, int ring) { uint64_t seq; @@ -305,20 +316,22 @@ int radeon_fence_wait_next(struct radeon_device *rdev, int ring) */ seq = atomic64_read(&rdev->fence_drv[ring].last_seq) + 1ULL; if (seq >= rdev->fence_drv[ring].seq) { - /* nothing to wait for, last_seq is already the last emited fence */ - return 0; + /* nothing to wait for, last_seq is + already the last emited fence */ + return -ENOENT; } - return radeon_fence_wait_seq(rdev, seq, ring, false); + return radeon_fence_wait_seq(rdev, seq, ring, false, false); } -int radeon_fence_wait_empty(struct radeon_device *rdev, int ring) +int radeon_fence_wait_empty_locked(struct radeon_device *rdev, int ring) { /* We are not protected by ring lock when reading current seq * but it's ok as wait empty is call from place where no more * activity can be scheduled so there won't be concurrent access * to seq value. */ - return radeon_fence_wait_seq(rdev, rdev->fence_drv[ring].seq, ring, false); + return radeon_fence_wait_seq(rdev, rdev->fence_drv[ring].seq, + ring, false, false); } struct radeon_fence *radeon_fence_ref(struct radeon_fence *fence) @@ -410,14 +423,16 @@ void radeon_fence_driver_fini(struct radeon_device *rdev) { int ring; + mutex_lock(&rdev->ring_lock); for (ring = 0; ring < RADEON_NUM_RINGS; ring++) { if (!rdev->fence_drv[ring].initialized) continue; - radeon_fence_wait_empty(rdev, ring); + radeon_fence_wait_empty_locked(rdev, ring); wake_up_all(&rdev->fence_drv[ring].queue); radeon_scratch_free(rdev, rdev->fence_drv[ring].scratch_reg); rdev->fence_drv[ring].initialized = false; } + mutex_unlock(&rdev->ring_lock); } -- cgit v1.2.1