On Thu, Jun 10, 2021 at 11:17:59AM +0200, Christian König wrote:
> Unwrap a the explicit fence if it is a dma_fence_chain and
> sync to the first fence not matching the owner rules.
>
> Signed-off-by: Christian König <christian.koenig@xxxxxxx>
> ---
> drivers/gpu/drm/amd/amdgpu/amdgpu_sync.c | 118 +++++++++++++----------
> 1 file changed, 68 insertions(+), 50 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_sync.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_sync.c
> index 1b2ceccaf5b0..862eb3c1c4c5 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_sync.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_sync.c
> @@ -28,6 +28,8 @@
> * Christian König <christian.koenig@xxxxxxx>
> */
>
> +#include <linux/dma-fence-chain.h>
> +
> #include "amdgpu.h"
> #include "amdgpu_trace.h"
> #include "amdgpu_amdkfd.h"
> @@ -186,6 +188,55 @@ int amdgpu_sync_vm_fence(struct amdgpu_sync *sync, struct dma_fence *fence)
> return amdgpu_sync_fence(sync, fence);
> }
>
> +/* Determine based on the owner and mode if we should sync to a fence or not */
> +static bool amdgpu_sync_test_fence(struct amdgpu_device *adev,
> + enum amdgpu_sync_mode mode,
> + void *owner, struct dma_fence *f)
> +{
> + void *fence_owner = amdgpu_sync_get_owner(f);
> +
> + /* Always sync to moves, no matter what */
> + if (fence_owner == AMDGPU_FENCE_OWNER_UNDEFINED)
> + return true;
> +
> + /* We only want to trigger KFD eviction fences on
> + * evict or move jobs. Skip KFD fences otherwise.
> + */
> + if (fence_owner == AMDGPU_FENCE_OWNER_KFD &&
> + owner != AMDGPU_FENCE_OWNER_UNDEFINED)
> + return false;
> +
> + /* Never sync to VM updates either. */
> + if (fence_owner == AMDGPU_FENCE_OWNER_VM &&
> + owner != AMDGPU_FENCE_OWNER_UNDEFINED)
> + return false;
> +
> + /* Ignore fences depending on the sync mode */
> + switch (mode) {
> + case AMDGPU_SYNC_ALWAYS:
> + return true;
> +
> + case AMDGPU_SYNC_NE_OWNER:
> + if (amdgpu_sync_same_dev(adev, f) &&
> + fence_owner == owner)
> + return false;
> + break;
> +
> + case AMDGPU_SYNC_EQ_OWNER:
> + if (amdgpu_sync_same_dev(adev, f) &&
> + fence_owner != owner)
> + return false;
> + break;
> +
> + case AMDGPU_SYNC_EXPLICIT:
> + return false;
> + }
> +
> + WARN(debug_evictions && fence_owner == AMDGPU_FENCE_OWNER_KFD,
> + "Adding eviction fence to sync obj");
> + return true;
> +}
> +
> /**
> * amdgpu_sync_resv - sync to a reservation object
> *
> @@ -211,67 +262,34 @@ int amdgpu_sync_resv(struct amdgpu_device *adev, struct amdgpu_sync *sync,
>
> /* always sync to the exclusive fence */
> f = dma_resv_excl_fence(resv);
> - r = amdgpu_sync_fence(sync, f);
> + dma_fence_chain_for_each(f, f) {
Jason has some helper for deep-walking fence chains/arrays here I think.
Might want to look into that, so that we have some consistency in how we
pile up multiple exclusive fences.
Anyway pretty much one of the versions I had in mind too, except I didn't
type it up.
Acked-by: Daniel Vetter <daniel.vetter@xxxxxxxx>
> + struct dma_fence_chain *chain = to_dma_fence_chain(f);
> +
> + if (amdgpu_sync_test_fence(adev, mode, owner, chain ?
> + chain->fence : f)) {
> + r = amdgpu_sync_fence(sync, f);
> + dma_fence_put(f);
> + if (r)
> + return r;
> + break;
> + }
> + }
>
> flist = dma_resv_shared_list(resv);
> - if (!flist || r)
> - return r;
> + if (!flist)
> + return 0;
>
> for (i = 0; i < flist->shared_count; ++i) {
> - void *fence_owner;
> -
> f = rcu_dereference_protected(flist->shared[i],
> dma_resv_held(resv));
>
> - fence_owner = amdgpu_sync_get_owner(f);
> -
> - /* Always sync to moves, no matter what */
> - if (fence_owner == AMDGPU_FENCE_OWNER_UNDEFINED) {
> + if (amdgpu_sync_test_fence(adev, mode, owner, f)) {
> r = amdgpu_sync_fence(sync, f);
> if (r)
> - break;
> - }
> -
> - /* We only want to trigger KFD eviction fences on
> - * evict or move jobs. Skip KFD fences otherwise.
> - */
> - if (fence_owner == AMDGPU_FENCE_OWNER_KFD &&
> - owner != AMDGPU_FENCE_OWNER_UNDEFINED)
> - continue;
> -
> - /* Never sync to VM updates either. */
> - if (fence_owner == AMDGPU_FENCE_OWNER_VM &&
> - owner != AMDGPU_FENCE_OWNER_UNDEFINED)
> - continue;
> -
> - /* Ignore fences depending on the sync mode */
> - switch (mode) {
> - case AMDGPU_SYNC_ALWAYS:
> - break;
> -
> - case AMDGPU_SYNC_NE_OWNER:
> - if (amdgpu_sync_same_dev(adev, f) &&
> - fence_owner == owner)
> - continue;
> - break;
> -
> - case AMDGPU_SYNC_EQ_OWNER:
> - if (amdgpu_sync_same_dev(adev, f) &&
> - fence_owner != owner)
> - continue;
> - break;
> -
> - case AMDGPU_SYNC_EXPLICIT:
> - continue;
> + return r;
> }
> -
> - WARN(debug_evictions && fence_owner == AMDGPU_FENCE_OWNER_KFD,
> - "Adding eviction fence to sync obj");
> - r = amdgpu_sync_fence(sync, f);
> - if (r)
> - break;
> }
> - return r;
> + return 0;
> }
>
> /**
> --
> 2.25.1
>
--
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch
