github.com/andy-kimball/arenaskl@v0.0.0-20200617143215-f701008588b9/race_test.go (about) 1 /* 2 * Copyright 2020 Dgraph Labs, Inc. and Contributors 3 * Modifications copyright (C) 2020 Andy Kimball and Contributors 4 * 5 * Licensed under the Apache License, Version 2.0 (the "License"); 6 * you may not use this file except in compliance with the License. 7 * You may obtain a copy of the License at 8 * 9 * http://www.apache.org/licenses/LICENSE-2.0 10 * 11 * Unless required by applicable law or agreed to in writing, software 12 * distributed under the License is distributed on an "AS IS" BASIS, 13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 * See the License for the specific language governing permissions and 15 * limitations under the License. 16 */ 17 18 package arenaskl 19 20 import ( 21 "testing" 22 23 "github.com/stretchr/testify/require" 24 ) 25 26 // TestNodeArenaEnd tests allocating a node at the boundary of an arena. In Go 27 // 1.14 when the race detector is running, Go will also perform some pointer 28 // alignment checks. It will detect alignment issues where a node's memory would 29 // straddle the arena boundary, with unused regions of the node struct dipping 30 // into unallocated memory. This test is only run when the race build tag is 31 // provided. 32 func TestNodeArenaEnd(t *testing.T) { 33 // Rather than hardcode an arena size at just the right size, try 34 // allocating using successively larger arena sizes until we allocate 35 // successfully. The prior attempt will have exercised the right code 36 // path. 37 for i := uint32(1); i < 256; i++ { 38 a := NewArena(i) 39 _, err := newNode(a, 1) 40 if err == nil { 41 // We reached an arena size big enough to allocate a node. If 42 // there's an issue at the boundary, the race detector would have 43 // found it by now. 44 t.Log(i) 45 break 46 } 47 require.Equal(t, ErrArenaFull, err) 48 } 49 }