1 | /* |
2 | * Copyright (c) 1999, 2019, Oracle and/or its affiliates. All rights reserved. |
3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
4 | * |
5 | * This code is free software; you can redistribute it and/or modify it |
6 | * under the terms of the GNU General Public License version 2 only, as |
7 | * published by the Free Software Foundation. |
8 | * |
9 | * This code is distributed in the hope that it will be useful, but WITHOUT |
10 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
11 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
12 | * version 2 for more details (a copy is included in the LICENSE file that |
13 | * accompanied this code). |
14 | * |
15 | * You should have received a copy of the GNU General Public License version |
16 | * 2 along with this work; if not, write to the Free Software Foundation, |
17 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
18 | * |
19 | * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
20 | * or visit www.oracle.com if you need additional information or have any |
21 | * questions. |
22 | * |
23 | */ |
24 | |
25 | #ifndef SHARE_GC_SHARED_THREADLOCALALLOCBUFFER_INLINE_HPP |
26 | #define SHARE_GC_SHARED_THREADLOCALALLOCBUFFER_INLINE_HPP |
27 | |
28 | #include "gc/shared/collectedHeap.hpp" |
29 | #include "gc/shared/threadLocalAllocBuffer.hpp" |
30 | #include "memory/universe.hpp" |
31 | #include "logging/log.hpp" |
32 | #include "runtime/thread.hpp" |
33 | #include "utilities/copy.hpp" |
34 | |
35 | inline HeapWord* ThreadLocalAllocBuffer::allocate(size_t size) { |
36 | invariants(); |
37 | HeapWord* obj = top(); |
38 | if (pointer_delta(end(), obj) >= size) { |
39 | // successful thread-local allocation |
40 | #ifdef ASSERT |
41 | // Skip mangling the space corresponding to the object header to |
42 | // ensure that the returned space is not considered parsable by |
43 | // any concurrent GC thread. |
44 | size_t hdr_size = oopDesc::header_size(); |
45 | Copy::fill_to_words(obj + hdr_size, size - hdr_size, badHeapWordVal); |
46 | #endif // ASSERT |
47 | // This addition is safe because we know that top is |
48 | // at least size below end, so the add can't wrap. |
49 | set_top(obj + size); |
50 | |
51 | invariants(); |
52 | return obj; |
53 | } |
54 | return NULL; |
55 | } |
56 | |
57 | inline size_t ThreadLocalAllocBuffer::compute_size(size_t obj_size) { |
58 | // Compute the size for the new TLAB. |
59 | // The "last" tlab may be smaller to reduce fragmentation. |
60 | // unsafe_max_tlab_alloc is just a hint. |
61 | const size_t available_size = Universe::heap()->unsafe_max_tlab_alloc(thread()) / HeapWordSize; |
62 | size_t new_tlab_size = MIN3(available_size, desired_size() + align_object_size(obj_size), max_size()); |
63 | |
64 | // Make sure there's enough room for object and filler int[]. |
65 | if (new_tlab_size < compute_min_size(obj_size)) { |
66 | // If there isn't enough room for the allocation, return failure. |
67 | log_trace(gc, tlab)("ThreadLocalAllocBuffer::compute_size(" SIZE_FORMAT ") returns failure" , |
68 | obj_size); |
69 | return 0; |
70 | } |
71 | log_trace(gc, tlab)("ThreadLocalAllocBuffer::compute_size(" SIZE_FORMAT ") returns " SIZE_FORMAT, |
72 | obj_size, new_tlab_size); |
73 | return new_tlab_size; |
74 | } |
75 | |
76 | inline size_t ThreadLocalAllocBuffer::compute_min_size(size_t obj_size) { |
77 | const size_t aligned_obj_size = align_object_size(obj_size); |
78 | const size_t size_with_reserve = aligned_obj_size + alignment_reserve(); |
79 | return MAX2(size_with_reserve, heap_word_size(MinTLABSize)); |
80 | } |
81 | |
82 | void ThreadLocalAllocBuffer::record_slow_allocation(size_t obj_size) { |
83 | // Raise size required to bypass TLAB next time. Why? Else there's |
84 | // a risk that a thread that repeatedly allocates objects of one |
85 | // size will get stuck on this slow path. |
86 | |
87 | set_refill_waste_limit(refill_waste_limit() + refill_waste_limit_increment()); |
88 | |
89 | _slow_allocations++; |
90 | |
91 | log_develop_trace(gc, tlab)("TLAB: %s thread: " INTPTR_FORMAT " [id: %2d]" |
92 | " obj: " SIZE_FORMAT |
93 | " free: " SIZE_FORMAT |
94 | " waste: " SIZE_FORMAT, |
95 | "slow" , p2i(thread()), thread()->osthread()->thread_id(), |
96 | obj_size, free(), refill_waste_limit()); |
97 | } |
98 | |
99 | #endif // SHARE_GC_SHARED_THREADLOCALALLOCBUFFER_INLINE_HPP |
100 | |