bpf: Remove migrate_{disable|enable} from bpf_local_storage_alloc()

These two callers of bpf_local_storage_alloc() are the same as
bpf_selem_alloc(): bpf_sk_storage_clone() and
bpf_local_storage_update(). The running contexts of these two callers
have already disabled migration, therefore, there is no need to add
extra migrate_{disable|enable} pair in bpf_local_storage_alloc().

Signed-off-by: Hou Tao <houtao1@huawei.com>
Link: https://lore.kernel.org/r/20250108010728.207536-15-houtao@huaweicloud.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Author: Hou Tao

kernel/bpf/bpf_local_storage.c

@@ -498,15 +498,11 @@ int bpf_local_storage_alloc(void *owner,
 	if (err)
 		return err;
 
-	if (smap->bpf_ma) {
-		migrate_disable();
+	if (smap->bpf_ma)
 		storage = bpf_mem_cache_alloc_flags(&smap->storage_ma, gfp_flags);
-		migrate_enable();
-	} else {
+	else
 		storage = bpf_map_kzalloc(&smap->map, sizeof(*storage),
 					  gfp_flags | __GFP_NOWARN);
-	}
-
 	if (!storage) {
 		err = -ENOMEM;
 		goto uncharge;