From 774b5fa509a97017715801739111a42fdc23d590 Mon Sep 17 00:00:00 2001 From: Oak Zeng Date: Mon, 2 Dec 2024 21:19:29 -0500 Subject: [PATCH] drm/xe: Avoid evicting object of the same vm in none fault mode MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit BO validation during vm_bind could trigger memory eviction when system runs under memory pressure. Right now we blindly evict BOs of all VMs. This scheme has a problem when system runs in none recoverable page fault mode: even though the vm_bind could be successful by evicting BOs, the later the rebinding of the evicted BOs would fail. So it is better to report an out-of- memory failure at vm_bind time than at time of rebinding where xekmd currently doesn't have a good mechanism to report error to user space. This patch implemented a scheme to only evict objects of other VMs during vm_bind time. Object of the same VM will skip eviction. If we failed to find enough memory for vm_bind, we report error to user space at vm_bind time. This scheme is not needed for recoverable page fault mode under what we can dynamically fault-in pages on demand. v1: Use xe_vm_in_preempt_fence_mode instead of stack variable (Thomas) Signed-off-by: Oak Zeng Suggested-by: Thomas Hellström Reviewed-by: Thomas Hellström Link: https://patchwork.freedesktop.org/patch/msgid/20241203021929.1919730-1-oak.zeng@intel.com Signed-off-by: Rodrigo Vivi --- drivers/gpu/drm/xe/xe_vm.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/xe/xe_vm.c b/drivers/gpu/drm/xe/xe_vm.c index 183ec8f7698a..74d684708b00 100644 --- a/drivers/gpu/drm/xe/xe_vm.c +++ b/drivers/gpu/drm/xe/xe_vm.c @@ -2360,13 +2360,15 @@ static int vma_lock_and_validate(struct drm_exec *exec, struct xe_vma *vma, bool validate) { struct xe_bo *bo = xe_vma_bo(vma); + struct xe_vm *vm = xe_vma_vm(vma); int err = 0; if (bo) { if (!bo->vm) err = drm_exec_lock_obj(exec, &bo->ttm.base); if (!err && validate) - err = xe_bo_validate(bo, xe_vma_vm(vma), true); + err = xe_bo_validate(bo, vm, + !xe_vm_in_preempt_fence_mode(vm)); } return err;