Re: [PATCH v6] drm/amdgpu: handle IH ring1 overflow

[philip yang]

On 2021-11-25 2:11 a.m., Christian König wrote:

Am 25.11.21 um 02:56 schrieb Felix Kuehling:

Am 2021-11-24 um 5:58 p.m. schrieb Philip Yang:
[SNIP]

  #define amdgpu_ih_get_wptr(adev, ih) (adev)->irq.ih_funcs->get_wptr((adev), (ih))
  #define amdgpu_ih_decode_iv(adev, iv) \
      (adev)->irq.ih_funcs->decode_iv((adev), (ih), (iv))
+#define amdgpu_ih_decode_iv_ts(adev, ih, rptr, offset) \
+    (WARN_ON_ONCE(!(adev)->irq.ih_funcs->decode_iv_ts) ? 0 : \
+    (adev)->irq.ih_funcs->decode_iv_ts((ih), (rptr), (offset)))
  #define amdgpu_ih_set_rptr(adev, ih) (adev)->irq.ih_funcs->set_rptr((adev), (ih))
    int amdgpu_ih_ring_init(struct amdgpu_device *adev, struct amdgpu_ih_ring *ih,
@@ -89,10 +99,12 @@ int amdgpu_ih_ring_init(struct amdgpu_device *adev, struct amdgpu_ih_ring *ih,
  void amdgpu_ih_ring_fini(struct amdgpu_device *adev, struct amdgpu_ih_ring *ih);
  void amdgpu_ih_ring_write(struct amdgpu_ih_ring *ih, const uint32_t *iv,
                unsigned int num_dw);
-int amdgpu_ih_wait_on_checkpoint_process(struct amdgpu_device *adev,
-                    struct amdgpu_ih_ring *ih);
+int amdgpu_ih_wait_on_checkpoint_process_ts(struct amdgpu_device *adev,
+                        struct amdgpu_ih_ring *ih);
  int amdgpu_ih_process(struct amdgpu_device *adev, struct amdgpu_ih_ring *ih);
  void amdgpu_ih_decode_iv_helper(struct amdgpu_device *adev,
                  struct amdgpu_ih_ring *ih,
                  struct amdgpu_iv_entry *entry);
+uint64_t amdgpu_ih_decode_iv_ts_helper(struct amdgpu_ih_ring *ih, u32 rptr,
+                       signed int offset);
  #endif
diff --git a/drivers/gpu/drm/amd/amdgpu/gmc_v10_0.c b/drivers/gpu/drm/amd/amdgpu/gmc_v10_0.c
index 3ec5ff5a6dbe..b129898db433 100644
--- a/drivers/gpu/drm/amd/amdgpu/gmc_v10_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/gmc_v10_0.c
@@ -119,6 +119,11 @@ static int gmc_v10_0_process_interrupt(struct amdgpu_device *adev,
              return 1;
          }
  +        /* Stale retry fault if timestamp goes backward */
+        if (entry->ih == &adev->irq.ih1 &&
+            amdgpu_ih_ts_after(entry->timestamp, entry->ih->processed_timestamp))
+            return 1;
+

This check should go before amdgpu_gmc_filter_faults. Otherwise
amdgpu_gmc_filter_faults may later drop a real fault because it added a
stale fault in its hash table.

I was already wondering if we shouldn't move all of this completely into amdgpu_gmc_filter_faults().

I mean essentially we are filtering faults here once more, just based on a different criteria.

It is good idea, it also removes duplicate code in different interrupt handler. And retry fault timestamp check for both ring0 and ring1.

Thanks,

Philip

Regards,
Christian.