Re: [PATCH 1/1] Revert "drm/amdkfd: process_info lock not needed for svm"

[Felix Kuehling]

Am 2022-02-25 um 15:12 schrieb Philip Yang:

This reverts commit 3abfe30d803e62cc75dec254eefab3b04d69219b.

To fix deadlock in kFDSVMEvictTest when xnack off.

Please add your Signed-off-by. With that fixed, the patch is

Reviewed-by: Felix Kuehling <felix.kuehl...@amd.com>

---
  drivers/gpu/drm/amd/amdkfd/kfd_svm.c | 9 +++++++++
  1 file changed, 9 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c 
b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
index b71d47afd243..509d915cbe69 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
@@ -1629,6 +1629,7 @@ 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;
@@ -1645,6 +1646,7 @@ static void svm_range_restore_work(struct work_struct 
*work)
        pr_debug("restore svm ranges\n");

p = container_of(svms, struct kfd_process, svms);

+       process_info = p->kgd_process_info;

/* Keep mm reference when svm_range_validate_and_map ranges */

        mm = get_task_mm(p->lead_thread);
@@ -1653,6 +1655,7 @@ static void svm_range_restore_work(struct work_struct 
*work)
                return;
        }

+ mutex_lock(&process_info->lock);

        svm_range_list_lock_and_flush_work(svms, mm);
        mutex_lock(&svms->lock);

@@ -1705,6 +1708,7 @@ 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);
        mmput(mm);

/* If validation failed, reschedule another attempt */

@@ -3209,6 +3213,7 @@ svm_range_set_attr(struct kfd_process *p, struct 
mm_struct *mm,
                   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 list_head update_list;
        struct list_head insert_list;
        struct list_head remove_list;
@@ -3226,6 +3231,8 @@ svm_range_set_attr(struct kfd_process *p, struct 
mm_struct *mm,

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);

@@ -3300,6 +3307,8 @@ svm_range_set_attr(struct kfd_process *p, struct 
mm_struct *mm,
        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);