Free up a pasid after all fences signaled.
v2: also handle the case when we can't allocate a fence array.
Signed-off-by: Christian König <christian.koenig@xxxxxxx>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_ids.c | 82 +++++++++++++++++++++++++++++++++
drivers/gpu/drm/amd/amdgpu/amdgpu_ids.h | 2 +
2 files changed, 84 insertions(+)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ids.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ids.c
index 5248a3232aff..842caa5ed73b 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ids.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ids.c
@@ -40,6 +40,12 @@
*/
static DEFINE_IDA(amdgpu_pasid_ida);
+/* Helper to free pasid from a fence callback */
+struct amdgpu_pasid_cb {
+ struct dma_fence_cb cb;
+ unsigned int pasid;
+};
+
/**
* amdgpu_pasid_alloc - Allocate a PASID
* @bits: Maximum width of the PASID in bits, must be at least 1
@@ -75,6 +81,82 @@ void amdgpu_pasid_free(unsigned int pasid)
ida_simple_remove(&amdgpu_pasid_ida, pasid);
}
+static void amdgpu_pasid_free_cb(struct dma_fence *fence,
+ struct dma_fence_cb *_cb)
+{
+ struct amdgpu_pasid_cb *cb =
+ container_of(_cb, struct amdgpu_pasid_cb, cb);
+
+ amdgpu_pasid_free(cb->pasid);
+ dma_fence_put(fence);
+ kfree(cb);
+}
+
+/**
+ * amdgpu_pasid_free_delayed - free pasid when fences signal
+ *
+ * @resv: reservation object with the fences to wait for
+ * @pasid: pasid to free
+ *
+ * Free the pasid only after all the fences in resv are signaled.
+ */
+void amdgpu_pasid_free_delayed(struct reservation_object *resv,
+ unsigned int pasid)
+{
+ struct dma_fence *fence, **fences;
+ struct amdgpu_pasid_cb *cb;
+ unsigned count;
+ int r;
+
+ r = reservation_object_get_fences_rcu(resv, NULL, &count, &fences);
+ if (r)
+ goto fallback;
+
+ if (count == 0) {
+ amdgpu_pasid_free(pasid);
+ return;
+ }
+
+ if (count == 1) {
+ fence = fences[0];
+ kfree(fences);
+ } else {
+ uint64_t context = dma_fence_context_alloc(1);
+ struct dma_fence_array *array;
+
+ array = dma_fence_array_create(count, fences, context,
+ 1, false);
+ if (!array) {
+ kfree(fences);
+ goto fallback;
+ }
+ fence = &array->base;
+ }
+
+ cb = kmalloc(sizeof(*cb), GFP_KERNEL);
+ if (!cb) {
+ /* Last resort when we are OOM */
+ dma_fence_wait(fence, false);
+ dma_fence_put(fence);
+ amdgpu_pasid_free(pasid);
+ } else {
+ cb->pasid = pasid;
+ if (dma_fence_add_callback(fence, &cb->cb,
+ amdgpu_pasid_free_cb))
+ amdgpu_pasid_free_cb(fence, &cb->cb);
+ }
+
+ return;
+
+fallback:
+ /* Not enough memory for the delayed delete, as last resort
+ * block for all the fences to complete.
+ */
+ reservation_object_wait_timeout_rcu(resv, true, false,
+ MAX_SCHEDULE_TIMEOUT);
+ amdgpu_pasid_free(pasid);
+}
+
/*
* VMID manager
*
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ids.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_ids.h
index ad931fa570b3..38f37c16fc5e 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ids.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ids.h
@@ -69,6 +69,8 @@ struct amdgpu_vmid_mgr {
int amdgpu_pasid_alloc(unsigned int bits);
void amdgpu_pasid_free(unsigned int pasid);
+void amdgpu_pasid_free_delayed(struct reservation_object *resv,
+ unsigned int pasid);
bool amdgpu_vmid_had_gpu_reset(struct amdgpu_device *adev,
struct amdgpu_vmid *id);
--
2.14.1
