[PATCH 06/20] drm/radeon: rework locking ring emission mutex in fence deadlock detection
Christian König
deathsimple at vodafone.de
Mon May 7 04:42:41 PDT 2012
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.
Signed-off-by: Christian König <deathsimple at vodafone.de>
---
drivers/gpu/drm/radeon/radeon.h | 4 +-
drivers/gpu/drm/radeon/radeon_device.c | 5 +++-
drivers/gpu/drm/radeon/radeon_fence.c | 39 ++++++++++++++++++++-----------
drivers/gpu/drm/radeon/radeon_pm.c | 8 +-----
drivers/gpu/drm/radeon/radeon_ring.c | 6 +----
5 files changed, 33 insertions(+), 29 deletions(-)
diff --git a/drivers/gpu/drm/radeon/radeon.h b/drivers/gpu/drm/radeon/radeon.h
index 7c87117..701094b 100644
--- a/drivers/gpu/drm/radeon/radeon.h
+++ b/drivers/gpu/drm/radeon/radeon.h
@@ -284,8 +284,8 @@ int radeon_fence_emit(struct radeon_device *rdev, struct radeon_fence *fence);
void radeon_fence_process(struct radeon_device *rdev, int ring);
bool radeon_fence_signaled(struct radeon_fence *fence);
int radeon_fence_wait(struct radeon_fence *fence, bool interruptible);
-int radeon_fence_wait_next(struct radeon_device *rdev, int ring);
-int radeon_fence_wait_empty(struct radeon_device *rdev, int ring);
+int radeon_fence_wait_next_locked(struct radeon_device *rdev, int ring);
+int radeon_fence_wait_empty_locked(struct radeon_device *rdev, int ring);
struct radeon_fence *radeon_fence_ref(struct radeon_fence *fence);
void radeon_fence_unref(struct radeon_fence **fence);
unsigned radeon_fence_count_emitted(struct radeon_device *rdev, int ring);
diff --git a/drivers/gpu/drm/radeon/radeon_device.c b/drivers/gpu/drm/radeon/radeon_device.c
index 0e7b72a..b827b2e 100644
--- a/drivers/gpu/drm/radeon/radeon_device.c
+++ b/drivers/gpu/drm/radeon/radeon_device.c
@@ -912,9 +912,12 @@ int radeon_suspend_kms(struct drm_device *dev, pm_message_t state)
}
/* evict vram memory */
radeon_bo_evict_vram(rdev);
+
+ mutex_lock(&rdev->ring_lock);
/* wait for gpu to finish processing current batch */
for (i = 0; i < RADEON_NUM_RINGS; i++)
- radeon_fence_wait_empty(rdev, i);
+ radeon_fence_wait_empty_locked(rdev, i);
+ mutex_unlock(&rdev->ring_lock);
radeon_save_bios_scratch_regs(rdev);
diff --git a/drivers/gpu/drm/radeon/radeon_fence.c b/drivers/gpu/drm/radeon/radeon_fence.c
index f386807..8034b42 100644
--- a/drivers/gpu/drm/radeon/radeon_fence.c
+++ b/drivers/gpu/drm/radeon/radeon_fence.c
@@ -192,7 +192,7 @@ 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;
@@ -247,8 +247,14 @@ 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) {
+ mutex_unlock(&rdev->ring_lock);
continue;
}
@@ -262,15 +268,15 @@ 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;
+ mutex_unlock(&rdev->ring_lock);
return -EDEADLK;
}
+
+ if (lock_ring) {
+ mutex_unlock(&rdev->ring_lock);
+ }
}
}
return 0;
@@ -285,7 +291,8 @@ 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;
}
@@ -293,7 +300,7 @@ 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;
@@ -303,20 +310,22 @@ 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)
@@ -418,14 +427,16 @@ 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);
}
diff --git a/drivers/gpu/drm/radeon/radeon_pm.c b/drivers/gpu/drm/radeon/radeon_pm.c
index 7c38745..0882554 100644
--- a/drivers/gpu/drm/radeon/radeon_pm.c
+++ b/drivers/gpu/drm/radeon/radeon_pm.c
@@ -270,13 +270,7 @@ static void radeon_pm_set_clocks(struct radeon_device *rdev)
} else {
struct radeon_ring *ring = &rdev->ring[RADEON_RING_TYPE_GFX_INDEX];
if (ring->ready) {
- struct radeon_fence *fence;
- radeon_ring_alloc(rdev, ring, 64);
- radeon_fence_create(rdev, &fence, radeon_ring_index(rdev, ring));
- radeon_fence_emit(rdev, fence);
- radeon_ring_commit(rdev, ring);
- radeon_fence_wait(fence, false);
- radeon_fence_unref(&fence);
+ radeon_fence_wait_empty_locked(rdev, RADEON_RING_TYPE_GFX_INDEX);
}
}
radeon_unmap_vram_bos(rdev);
diff --git a/drivers/gpu/drm/radeon/radeon_ring.c b/drivers/gpu/drm/radeon/radeon_ring.c
index 4ae222b..2fdc8c3 100644
--- a/drivers/gpu/drm/radeon/radeon_ring.c
+++ b/drivers/gpu/drm/radeon/radeon_ring.c
@@ -347,9 +347,7 @@ int radeon_ring_alloc(struct radeon_device *rdev, struct radeon_ring *ring, unsi
if (ndw < ring->ring_free_dw) {
break;
}
- mutex_unlock(&rdev->ring_lock);
- r = radeon_fence_wait_next(rdev, radeon_ring_index(rdev, ring));
- mutex_lock(&rdev->ring_lock);
+ r = radeon_fence_wait_next_locked(rdev, radeon_ring_index(rdev, ring));
if (r)
return r;
}
@@ -408,7 +406,6 @@ void radeon_ring_force_activity(struct radeon_device *rdev, struct radeon_ring *
{
int r;
- mutex_lock(&rdev->ring_lock);
radeon_ring_free_size(rdev, ring);
if (ring->rptr == ring->wptr) {
r = radeon_ring_alloc(rdev, ring, 1);
@@ -417,7 +414,6 @@ void radeon_ring_force_activity(struct radeon_device *rdev, struct radeon_ring *
radeon_ring_commit(rdev, ring);
}
}
- mutex_unlock(&rdev->ring_lock);
}
void radeon_ring_lockup_update(struct radeon_ring *ring)
--
1.7.5.4
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