diff options
Diffstat (limited to 'drivers/gpu/drm/ttm/ttm_bo_vm.c')
| -rw-r--r-- | drivers/gpu/drm/ttm/ttm_bo_vm.c | 26 |
1 files changed, 20 insertions, 6 deletions
diff --git a/drivers/gpu/drm/ttm/ttm_bo_vm.c b/drivers/gpu/drm/ttm/ttm_bo_vm.c index ac617f3ecd0c..b249ab9b1eb2 100644 --- a/drivers/gpu/drm/ttm/ttm_bo_vm.c +++ b/drivers/gpu/drm/ttm/ttm_bo_vm.c @@ -107,13 +107,28 @@ static int ttm_bo_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf) /* * Work around locking order reversal in fault / nopfn * between mmap_sem and bo_reserve: Perform a trylock operation - * for reserve, and if it fails, retry the fault after scheduling. + * for reserve, and if it fails, retry the fault after waiting + * for the buffer to become unreserved. */ - - ret = ttm_bo_reserve(bo, true, true, false, 0); + ret = ttm_bo_reserve(bo, true, true, false, NULL); if (unlikely(ret != 0)) { - if (ret == -EBUSY) - set_need_resched(); + if (ret != -EBUSY) + return VM_FAULT_NOPAGE; + + if (vmf->flags & FAULT_FLAG_ALLOW_RETRY) { + if (!(vmf->flags & FAULT_FLAG_RETRY_NOWAIT)) { + up_read(&vma->vm_mm->mmap_sem); + (void) ttm_bo_wait_unreserved(bo); + } + + return VM_FAULT_RETRY; + } + + /* + * If we'd want to change locking order to + * mmap_sem -> bo::reserve, we'd use a blocking reserve here + * instead of retrying the fault... + */ return VM_FAULT_NOPAGE; } @@ -123,7 +138,6 @@ static int ttm_bo_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf) case 0: break; case -EBUSY: - set_need_resched(); case -ERESTARTSYS: retval = VM_FAULT_NOPAGE; goto out_unlock; |