drm/amdkfd: Handle errors from svm validate and map

[ Upstream commit eb3c357bcb286e89386e89302061fe717fe4e562 ]

If new range is splited to multiple pranges with max_svm_range_pages
alignment and added to update_list, svm validate and map should keep
going after error to make sure prange->mapped_to_gpu flag is up to date
for the whole range.

svm validate and map update set prange->mapped_to_gpu after mapping to
GPUs successfully, otherwise clear prange->mapped_to_gpu flag (for
update mapping case) instead of setting error flag, we can remove
the redundant error flag to simpliy code.

Refactor to remove goto and update prange->mapped_to_gpu flag inside
svm_range_lock, to guarant we always evict queues or unmap from GPUs if
there are invalid ranges.

After svm validate and map return error -EAGIN, the caller retry will
update the mapping for the whole range again.

Fixes: c22b04407097 ("drm/amdkfd: flag added to handle errors from svm validate and map")
Signed-off-by: Philip Yang <Philip.Yang@amd.com>
Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com>
Tested-by: James Zhu <james.zhu@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
index dfc11699e79ab0211aa100c4b09602408fa28222..2a42fbddcb7ae0a409d1c575e7524ab904aa8cdd 100644 (file)
--- a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
@@ -820,7 +820,7 @@ svm_range_is_same_attrs(struct kfd_process *p, struct svm_range *prange,
                }
        }
 
-       return !prange->is_error_flag;
+       return true;
 }
 
 /**
@@ -1662,71 +1662,66 @@ static int svm_range_validate_and_map(struct mm_struct *mm,
 
        start = prange->start << PAGE_SHIFT;
        end = (prange->last + 1) << PAGE_SHIFT;
-       for (addr = start; addr < end && !r; ) {
+       for (addr = start; !r && addr < end; ) {
                struct hmm_range *hmm_range;
                struct vm_area_struct *vma;
-               unsigned long next;
+               unsigned long next = 0;
                unsigned long offset;
                unsigned long npages;
                bool readonly;
 
                vma = vma_lookup(mm, addr);
-               if (!vma) {
+               if (vma) {
+                       readonly = !(vma->vm_flags & VM_WRITE);
+
+                       next = min(vma->vm_end, end);
+                       npages = (next - addr) >> PAGE_SHIFT;
+                       WRITE_ONCE(p->svms.faulting_task, current);
+                       r = amdgpu_hmm_range_get_pages(&prange->notifier, addr, npages,
+                                                      readonly, owner, NULL,
+                                                      &hmm_range);
+                       WRITE_ONCE(p->svms.faulting_task, NULL);
+                       if (r) {
+                               pr_debug("failed %d to get svm range pages\n", r);
+                               if (r == -EBUSY)
+                                       r = -EAGAIN;
+                       }
+               } else {
                        r = -EFAULT;
-                       goto unreserve_out;
-               }
-               readonly = !(vma->vm_flags & VM_WRITE);
-
-               next = min(vma->vm_end, end);
-               npages = (next - addr) >> PAGE_SHIFT;
-               WRITE_ONCE(p->svms.faulting_task, current);
-               r = amdgpu_hmm_range_get_pages(&prange->notifier, addr, npages,
-                                              readonly, owner, NULL,
-                                              &hmm_range);
-               WRITE_ONCE(p->svms.faulting_task, NULL);
-               if (r) {
-                       pr_debug("failed %d to get svm range pages\n", r);
-                       if (r == -EBUSY)
-                               r = -EAGAIN;
-                       goto unreserve_out;
                }
 
-               offset = (addr - start) >> PAGE_SHIFT;
-               r = svm_range_dma_map(prange, ctx->bitmap, offset, npages,
-                                     hmm_range->hmm_pfns);
-               if (r) {
-                       pr_debug("failed %d to dma map range\n", r);
-                       goto unreserve_out;
+               if (!r) {
+                       offset = (addr - start) >> PAGE_SHIFT;
+                       r = svm_range_dma_map(prange, ctx->bitmap, offset, npages,
+                                             hmm_range->hmm_pfns);
+                       if (r)
+                               pr_debug("failed %d to dma map range\n", r);
                }
 
                svm_range_lock(prange);
-               if (amdgpu_hmm_range_get_pages_done(hmm_range)) {
+               if (!r && amdgpu_hmm_range_get_pages_done(hmm_range)) {
                        pr_debug("hmm update the range, need validate again\n");
                        r = -EAGAIN;
-                       goto unlock_out;
                }
-               if (!list_empty(&prange->child_list)) {
+
+               if (!r && !list_empty(&prange->child_list)) {
                        pr_debug("range split by unmap in parallel, validate again\n");
                        r = -EAGAIN;
-                       goto unlock_out;
                }
 
-               r = svm_range_map_to_gpus(prange, offset, npages, readonly,
-                                         ctx->bitmap, wait, flush_tlb);
+               if (!r)
+                       r = svm_range_map_to_gpus(prange, offset, npages, readonly,
+                                                 ctx->bitmap, wait, flush_tlb);
+
+               if (!r && next == end)
+                       prange->mapped_to_gpu = true;
 
-unlock_out:
                svm_range_unlock(prange);
 
                addr = next;
        }
 
-       if (addr == end)
-               prange->mapped_to_gpu = true;
-
-unreserve_out:
        svm_range_unreserve_bos(ctx);
-
-       prange->is_error_flag = !!r;
        if (!r)
                prange->validate_timestamp = ktime_get_boottime();
 
@@ -2095,7 +2090,8 @@ svm_range_add(struct kfd_process *p, uint64_t start, uint64_t size,
                next = interval_tree_iter_next(node, start, last);
                next_start = min(node->last, last) + 1;
 
-               if (svm_range_is_same_attrs(p, prange, nattr, attrs)) {
+               if (svm_range_is_same_attrs(p, prange, nattr, attrs) &&
+                   prange->mapped_to_gpu) {
                        /* nothing to do */
                } else if (node->start < start || node->last > last) {
                        /* node intersects the update range and its attributes
@@ -3505,7 +3501,7 @@ svm_range_set_attr(struct kfd_process *p, struct mm_struct *mm,
        struct svm_range *next;
        bool update_mapping = false;
        bool flush_tlb;
-       int r = 0;
+       int r, ret = 0;
 
        pr_debug("pasid 0x%x svms 0x%p [0x%llx 0x%llx] pages 0x%llx\n",
                 p->pasid, &p->svms, start, start + size - 1, size);
@@ -3593,7 +3589,7 @@ svm_range_set_attr(struct kfd_process *p, struct mm_struct *mm,
 out_unlock_range:
                mutex_unlock(&prange->migrate_mutex);
                if (r)
-                       break;
+                       ret = r;
        }
 
        dynamic_svm_range_dump(svms);
@@ -3606,7 +3602,7 @@ out:
        pr_debug("pasid 0x%x svms 0x%p [0x%llx 0x%llx] done, r=%d\n", p->pasid,
                 &p->svms, start, start + size - 1, r);
 
-       return r;
+       return ret ? ret : r;
 }
 
 static int

diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_svm.h b/drivers/gpu/drm/amd/amdkfd/kfd_svm.h
index c216c8dd13c6c2b79765ee291f121a7c83e6db0e..25f711905738654de07c830217c744cab679e3c7 100644 (file)
--- a/drivers/gpu/drm/amd/amdkfd/kfd_svm.h
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_svm.h
@@ -133,7 +133,6 @@ struct svm_range {
        DECLARE_BITMAP(bitmap_access, MAX_GPU_INSTANCE);
        DECLARE_BITMAP(bitmap_aip, MAX_GPU_INSTANCE);
        bool                            mapped_to_gpu;
-       bool                            is_error_flag;
 };
 
 static inline void svm_range_lock(struct svm_range *prange)