[PATCH 3/5] drm/amdkfd: optimize svm range evict

[Eric Huang]

It is to avoid unnecessary queue eviction when range
is not mapped to gpu.

Signed-off-by: Eric Huang <jinhuieric.huang at amd.com>
---
 drivers/gpu/drm/amd/amdkfd/kfd_svm.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
index 586bef4fcc8a..1f1f8f2dfa28 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
@@ -1775,8 +1775,12 @@ svm_range_evict(struct svm_range *prange, struct mm_struct *mm,
 	if (!p->xnack_enabled ||
 	    (prange->flags & KFD_IOCTL_SVM_FLAG_GPU_ALWAYS_MAPPED)) {
 		int evicted_ranges;
+		bool mapped = prange->mapped_to_gpu;
 
 		list_for_each_entry(pchild, &prange->child_list, child_list) {
+			if (!pchild->mapped_to_gpu)
+				continue;
+			mapped = true;
 			mutex_lock_nested(&pchild->lock, 1);
 			if (pchild->start <= last && pchild->last >= start) {
 				pr_debug("increment pchild invalid [0x%lx 0x%lx]\n",
@@ -1786,6 +1790,9 @@ svm_range_evict(struct svm_range *prange, struct mm_struct *mm,
 			mutex_unlock(&pchild->lock);
 		}
 
+		if (!mapped)
+			return r;
+
 		if (prange->start <= last && prange->last >= start)
 			atomic_inc(&prange->invalid);
 
-- 
2.25.1