[RFC PATCH 03/28] drm/xe: Retry BO allocation

[Matthew Brost]

TTM doesn't support fair eviction via WW locking, this mitigated in by
using retry loops in exec and preempt rebind worker. Extend this retry
loop to BO allocation. Once TTM supports fair eviction this patch can be
reverted.

Signed-off-by: Matthew Brost <matthew.brost at intel.com>
---
 drivers/gpu/drm/xe/xe_bo.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/xe/xe_bo.c b/drivers/gpu/drm/xe/xe_bo.c
index cbe7bf098970..b6c6a4a3b4d4 100644
--- a/drivers/gpu/drm/xe/xe_bo.c
+++ b/drivers/gpu/drm/xe/xe_bo.c
@@ -1977,6 +1977,7 @@ int xe_gem_create_ioctl(struct drm_device *dev, void *data,
 	struct xe_file *xef = to_xe_file(file);
 	struct drm_xe_gem_create *args = data;
 	struct xe_vm *vm = NULL;
+	ktime_t end = 0;
 	struct xe_bo *bo;
 	unsigned int bo_flags;
 	u32 handle;
@@ -2042,11 +2043,14 @@ int xe_gem_create_ioctl(struct drm_device *dev, void *data,
 		vm = xe_vm_lookup(xef, args->vm_id);
 		if (XE_IOCTL_DBG(xe, !vm))
 			return -ENOENT;
+	}
+
+retry:
+	if (vm) {
 		err = xe_vm_lock(vm, true);
 		if (err)
 			goto out_vm;
 	}
-
 	bo = xe_bo_create_user(xe, NULL, vm, args->size, args->cpu_caching,
 			       bo_flags);
 
@@ -2055,6 +2059,8 @@ int xe_gem_create_ioctl(struct drm_device *dev, void *data,
 
 	if (IS_ERR(bo)) {
 		err = PTR_ERR(bo);
+		if (xe_vm_validate_should_retry(NULL, err, &end))
+			goto retry;
 		goto out_vm;
 	}
 
-- 
2.34.1