[PATCH 1/2] drm/amdkfd: process_info lock not needed for svm

[Philip Yang]

process_info->lock is used to protect kfd_bo_list, vm_list_head, n_vms
and userptr valid/inval list, svm_range_restore_work and
svm_range_set_attr don't access those, so do not need to take
process_info lock. This will avoid potential circular locking issue.

Signed-off-by: Philip Yang <philip.y...@amd.com>
---
 drivers/gpu/drm/amd/amdkfd/kfd_svm.c | 9 ---------
 1 file changed, 9 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c 
b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
index 187e8ab66baa..f2db49c7a8fd 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
@@ -1564,7 +1564,6 @@ svm_range_list_lock_and_flush_work(struct svm_range_list 
*svms,
 static void svm_range_restore_work(struct work_struct *work)
 {
        struct delayed_work *dwork = to_delayed_work(work);
-       struct amdkfd_process_info *process_info;
        struct svm_range_list *svms;
        struct svm_range *prange;
        struct kfd_process *p;
@@ -1584,12 +1583,10 @@ static void svm_range_restore_work(struct work_struct 
*work)
         * the lifetime of this thread, kfd_process and mm will be valid.
         */
        p = container_of(svms, struct kfd_process, svms);
-       process_info = p->kgd_process_info;
        mm = p->mm;
        if (!mm)
                return;
 
-       mutex_lock(&process_info->lock);
        svm_range_list_lock_and_flush_work(svms, mm);
        mutex_lock(&svms->lock);
 
@@ -1642,7 +1639,6 @@ static void svm_range_restore_work(struct work_struct 
*work)
 out_reschedule:
        mutex_unlock(&svms->lock);
        mmap_write_unlock(mm);
-       mutex_unlock(&process_info->lock);
 
        /* If validation failed, reschedule another attempt */
        if (evicted_ranges) {
@@ -3168,7 +3164,6 @@ static int
 svm_range_set_attr(struct kfd_process *p, uint64_t start, uint64_t size,
                   uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs)
 {
-       struct amdkfd_process_info *process_info = p->kgd_process_info;
        struct mm_struct *mm = current->mm;
        struct list_head update_list;
        struct list_head insert_list;
@@ -3187,8 +3182,6 @@ svm_range_set_attr(struct kfd_process *p, uint64_t start, 
uint64_t size,
 
        svms = &p->svms;
 
-       mutex_lock(&process_info->lock);
-
        svm_range_list_lock_and_flush_work(svms, mm);
 
        r = svm_range_is_valid(p, start, size);
@@ -3264,8 +3257,6 @@ svm_range_set_attr(struct kfd_process *p, uint64_t start, 
uint64_t size,
        mutex_unlock(&svms->lock);
        mmap_read_unlock(mm);
 out:
-       mutex_unlock(&process_info->lock);
-
        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);
 
-- 
2.17.1