From: Christian König Date: Wed, 27 Aug 2014 13:21:58 +0000 (+0200) Subject: drm/radeon: handle lockup in delayed work, v5 X-Git-Tag: firefly_0821_release~176^2~3035^2~75^2~3 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=0bfa4b41268ad5fd741f16f484e4fee190822ec6;p=firefly-linux-kernel-4.4.55.git drm/radeon: handle lockup in delayed work, v5 v5 (chk): complete rework, start when the first fence is emitted, stop when the last fence is signalled, make it work correctly with GPU resets, cleanup radeon_fence_wait_seq Signed-off-by: Maarten Lankhorst Signed-off-by: Christian König Signed-off-by: Alex Deucher --- diff --git a/drivers/gpu/drm/radeon/radeon.h b/drivers/gpu/drm/radeon/radeon.h index 8cd1b3f60d4a..74919ef57ac3 100644 --- a/drivers/gpu/drm/radeon/radeon.h +++ b/drivers/gpu/drm/radeon/radeon.h @@ -350,6 +350,7 @@ extern void evergreen_tiling_fields(unsigned tiling_flags, unsigned *bankw, * Fences. */ struct radeon_fence_driver { + struct radeon_device *rdev; uint32_t scratch_reg; uint64_t gpu_addr; volatile uint32_t *cpu_addr; @@ -357,6 +358,7 @@ struct radeon_fence_driver { uint64_t sync_seq[RADEON_NUM_RINGS]; atomic64_t last_seq; bool initialized; + struct delayed_work lockup_work; }; struct radeon_fence { diff --git a/drivers/gpu/drm/radeon/radeon_fence.c b/drivers/gpu/drm/radeon/radeon_fence.c index e8a28e7b39c7..ac15f3418478 100644 --- a/drivers/gpu/drm/radeon/radeon_fence.c +++ b/drivers/gpu/drm/radeon/radeon_fence.c @@ -97,6 +97,25 @@ static u32 radeon_fence_read(struct radeon_device *rdev, int ring) return seq; } +/** + * radeon_fence_schedule_check - schedule lockup check + * + * @rdev: radeon_device pointer + * @ring: ring index we should work with + * + * Queues a delayed work item to check for lockups. + */ +static void radeon_fence_schedule_check(struct radeon_device *rdev, int ring) +{ + /* + * Do not reset the timer here with mod_delayed_work, + * this can livelock in an interaction with TTM delayed destroy. + */ + queue_delayed_work(system_power_efficient_wq, + &rdev->fence_drv[ring].lockup_work, + RADEON_FENCE_JIFFIES_TIMEOUT); +} + /** * radeon_fence_emit - emit a fence on the requested ring * @@ -122,19 +141,21 @@ int radeon_fence_emit(struct radeon_device *rdev, (*fence)->ring = ring; radeon_fence_ring_emit(rdev, ring, *fence); trace_radeon_fence_emit(rdev->ddev, ring, (*fence)->seq); + radeon_fence_schedule_check(rdev, ring); return 0; } /** - * radeon_fence_process - process a fence + * radeon_fence_activity - check for fence activity * * @rdev: radeon_device pointer * @ring: ring index the fence is associated with * - * Checks the current fence value and wakes the fence queue - * if the sequence number has increased (all asics). + * Checks the current fence value and calculates the last + * signalled fence value. Returns true if activity occured + * on the ring, and the fence_queue should be waken up. */ -void radeon_fence_process(struct radeon_device *rdev, int ring) +static bool radeon_fence_activity(struct radeon_device *rdev, int ring) { uint64_t seq, last_seq, last_emitted; unsigned count_loop = 0; @@ -190,7 +211,67 @@ void radeon_fence_process(struct radeon_device *rdev, int ring) } } while (atomic64_xchg(&rdev->fence_drv[ring].last_seq, seq) > seq); - if (wake) + if (seq < last_emitted) + radeon_fence_schedule_check(rdev, ring); + + return wake; +} + +/** + * radeon_fence_check_lockup - check for hardware lockup + * + * @work: delayed work item + * + * Checks for fence activity and if there is none probe + * the hardware if a lockup occured. + */ +static void radeon_fence_check_lockup(struct work_struct *work) +{ + struct radeon_fence_driver *fence_drv; + struct radeon_device *rdev; + int ring; + + fence_drv = container_of(work, struct radeon_fence_driver, + lockup_work.work); + rdev = fence_drv->rdev; + ring = fence_drv - &rdev->fence_drv[0]; + + if (!down_read_trylock(&rdev->exclusive_lock)) { + /* just reschedule the check if a reset is going on */ + radeon_fence_schedule_check(rdev, ring); + return; + } + + if (radeon_fence_activity(rdev, ring)) + wake_up_all(&rdev->fence_queue); + + else if (radeon_ring_is_lockup(rdev, ring, &rdev->ring[ring])) { + + /* good news we believe it's a lockup */ + dev_warn(rdev->dev, "GPU lockup (current fence id " + "0x%016llx last fence id 0x%016llx on ring %d)\n", + (uint64_t)atomic64_read(&fence_drv->last_seq), + fence_drv->sync_seq[ring], ring); + + /* remember that we need an reset */ + rdev->needs_reset = true; + wake_up_all(&rdev->fence_queue); + } + up_read(&rdev->exclusive_lock); +} + +/** + * radeon_fence_process - process a fence + * + * @rdev: radeon_device pointer + * @ring: ring index the fence is associated with + * + * Checks the current fence value and wakes the fence queue + * if the sequence number has increased (all asics). + */ +void radeon_fence_process(struct radeon_device *rdev, int ring) +{ + if (radeon_fence_activity(rdev, ring)) wake_up_all(&rdev->fence_queue); } @@ -300,86 +381,43 @@ static bool radeon_fence_any_seq_signaled(struct radeon_device *rdev, u64 *seq) static int radeon_fence_wait_seq(struct radeon_device *rdev, u64 *target_seq, bool intr) { - uint64_t last_seq[RADEON_NUM_RINGS]; - bool signaled; - int i, r; - - while (!radeon_fence_any_seq_signaled(rdev, target_seq)) { + long r; + int i; - /* Save current sequence values, used to check for GPU lockups */ - for (i = 0; i < RADEON_NUM_RINGS; ++i) { - if (!target_seq[i]) - continue; + if (radeon_fence_any_seq_signaled(rdev, target_seq)) + return 0; - last_seq[i] = atomic64_read(&rdev->fence_drv[i].last_seq); - trace_radeon_fence_wait_begin(rdev->ddev, i, target_seq[i]); - radeon_irq_kms_sw_irq_get(rdev, i); - } + /* enable IRQs and tracing */ + for (i = 0; i < RADEON_NUM_RINGS; ++i) { + if (!target_seq[i]) + continue; - if (intr) { - r = wait_event_interruptible_timeout(rdev->fence_queue, ( - (signaled = radeon_fence_any_seq_signaled(rdev, target_seq)) - || rdev->needs_reset), RADEON_FENCE_JIFFIES_TIMEOUT); - } else { - r = wait_event_timeout(rdev->fence_queue, ( - (signaled = radeon_fence_any_seq_signaled(rdev, target_seq)) - || rdev->needs_reset), RADEON_FENCE_JIFFIES_TIMEOUT); - } + trace_radeon_fence_wait_begin(rdev->ddev, i, target_seq[i]); + radeon_irq_kms_sw_irq_get(rdev, i); + } - for (i = 0; i < RADEON_NUM_RINGS; ++i) { - if (!target_seq[i]) - continue; + if (intr) { + r = wait_event_interruptible_timeout(rdev->fence_queue, ( + radeon_fence_any_seq_signaled(rdev, target_seq) + || rdev->needs_reset), MAX_SCHEDULE_TIMEOUT); + } else { + r = wait_event_timeout(rdev->fence_queue, ( + radeon_fence_any_seq_signaled(rdev, target_seq) + || rdev->needs_reset), MAX_SCHEDULE_TIMEOUT); + } - radeon_irq_kms_sw_irq_put(rdev, i); - trace_radeon_fence_wait_end(rdev->ddev, i, target_seq[i]); - } + if (rdev->needs_reset) + r = -EDEADLK; - if (unlikely(r < 0)) - return r; + for (i = 0; i < RADEON_NUM_RINGS; ++i) { + if (!target_seq[i]) + continue; - if (unlikely(!signaled)) { - if (rdev->needs_reset) - return -EDEADLK; - - /* we were interrupted for some reason and fence - * isn't signaled yet, resume waiting */ - if (r) - continue; - - for (i = 0; i < RADEON_NUM_RINGS; ++i) { - if (!target_seq[i]) - continue; - - if (last_seq[i] != atomic64_read(&rdev->fence_drv[i].last_seq)) - break; - } - - if (i != RADEON_NUM_RINGS) - continue; - - for (i = 0; i < RADEON_NUM_RINGS; ++i) { - if (!target_seq[i]) - continue; - - if (radeon_ring_is_lockup(rdev, i, &rdev->ring[i])) - break; - } - - if (i < RADEON_NUM_RINGS) { - /* good news we believe it's a lockup */ - dev_warn(rdev->dev, "GPU lockup (waiting for " - "0x%016llx last fence id 0x%016llx on" - " ring %d)\n", - target_seq[i], last_seq[i], i); - - /* remember that we need an reset */ - rdev->needs_reset = true; - wake_up_all(&rdev->fence_queue); - return -EDEADLK; - } - } + radeon_irq_kms_sw_irq_put(rdev, i); + trace_radeon_fence_wait_end(rdev->ddev, i, target_seq[i]); } - return 0; + + return r < 0 ? r : 0; } /** @@ -711,6 +749,9 @@ static void radeon_fence_driver_init_ring(struct radeon_device *rdev, int ring) rdev->fence_drv[ring].sync_seq[i] = 0; atomic64_set(&rdev->fence_drv[ring].last_seq, 0); rdev->fence_drv[ring].initialized = false; + INIT_DELAYED_WORK(&rdev->fence_drv[ring].lockup_work, + radeon_fence_check_lockup); + rdev->fence_drv[ring].rdev = rdev; } /** @@ -760,6 +801,7 @@ void radeon_fence_driver_fini(struct radeon_device *rdev) /* no need to trigger GPU reset as we are unloading */ radeon_fence_driver_force_completion(rdev, ring); } + cancel_delayed_work_sync(&rdev->fence_drv[ring].lockup_work); wake_up_all(&rdev->fence_queue); radeon_scratch_free(rdev, rdev->fence_drv[ring].scratch_reg); rdev->fence_drv[ring].initialized = false; @@ -778,8 +820,10 @@ void radeon_fence_driver_fini(struct radeon_device *rdev) */ void radeon_fence_driver_force_completion(struct radeon_device *rdev, int ring) { - if (rdev->fence_drv[ring].initialized) + if (rdev->fence_drv[ring].initialized) { radeon_fence_write(rdev, rdev->fence_drv[ring].sync_seq[ring], ring); + cancel_delayed_work_sync(&rdev->fence_drv[ring].lockup_work); + } }