Mercurial > hg > truffle
annotate src/share/vm/memory/threadLocalAllocBuffer.inline.hpp @ 12301:2c022e432e10
8024974: Incorrect use of GC_locker::is_active()
Summary: SymbolTable and StringTable can make calls to GC_locker::is_active() outside a safepoint. This isn't safe because the GC_locker active state (lock count) is only updated at a safepoint and only remains valid as long as _needs_gc is true. However, outside a safepoint_needs_gc can change to false at any time, which makes it impossible to do a correct call to is_active() in that context. In this case these calls can just be removed since the input argument to basic_add() should never be on the heap and so there's no need to check the GC_locker state. This change also adjusts the assert() in is_active() to makes sure all calls to this function are always done under a safepoint.
Reviewed-by: brutisso, dcubed
Contributed-by: per.liden@oracle.com
| author | stefank |
|---|---|
| date | Fri, 20 Sep 2013 10:53:28 +0200 |
| parents | c760f78e0a53 |
| children | 78bbf4d43a14 |
| rev | line source |
|---|---|
| 0 | 1 /* |
| 1972 | 2 * Copyright (c) 1999, 2010, Oracle and/or its affiliates. All rights reserved. |
| 0 | 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 * | |
|
1552
c18cbe5936b8
6941466: Oracle rebranding changes for Hotspot repositories
trims
parents:
1165
diff
changeset
|
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
|
c18cbe5936b8
6941466: Oracle rebranding changes for Hotspot repositories
trims
parents:
1165
diff
changeset
|
20 * or visit www.oracle.com if you need additional information or have any |
|
c18cbe5936b8
6941466: Oracle rebranding changes for Hotspot repositories
trims
parents:
1165
diff
changeset
|
21 * questions. |
| 0 | 22 * |
| 23 */ | |
| 24 | |
| 1972 | 25 #ifndef SHARE_VM_MEMORY_THREADLOCALALLOCBUFFER_INLINE_HPP |
| 26 #define SHARE_VM_MEMORY_THREADLOCALALLOCBUFFER_INLINE_HPP | |
| 27 | |
| 28 #include "gc_interface/collectedHeap.hpp" | |
| 29 #include "memory/threadLocalAllocBuffer.hpp" | |
| 30 #include "runtime/atomic.hpp" | |
|
1983
c760f78e0a53
7003125: precompiled.hpp is included when precompiled headers are not used
stefank
parents:
1972
diff
changeset
|
31 #include "runtime/thread.hpp" |
| 1972 | 32 #include "utilities/copy.hpp" |
| 33 | |
| 0 | 34 inline HeapWord* ThreadLocalAllocBuffer::allocate(size_t size) { |
| 35 invariants(); | |
| 36 HeapWord* obj = top(); | |
| 37 if (pointer_delta(end(), obj) >= size) { | |
| 38 // successful thread-local allocation | |
|
1165
2dd52dea6d28
6902115: G1:assert(ignore_max_completed||thread->is_Java_thread()||SafepointSynchronize::is_at_safepoint())
johnc
parents:
0
diff
changeset
|
39 #ifdef ASSERT |
|
2dd52dea6d28
6902115: G1:assert(ignore_max_completed||thread->is_Java_thread()||SafepointSynchronize::is_at_safepoint())
johnc
parents:
0
diff
changeset
|
40 // Skip mangling the space corresponding to the object header to |
|
2dd52dea6d28
6902115: G1:assert(ignore_max_completed||thread->is_Java_thread()||SafepointSynchronize::is_at_safepoint())
johnc
parents:
0
diff
changeset
|
41 // ensure that the returned space is not considered parsable by |
|
2dd52dea6d28
6902115: G1:assert(ignore_max_completed||thread->is_Java_thread()||SafepointSynchronize::is_at_safepoint())
johnc
parents:
0
diff
changeset
|
42 // any concurrent GC thread. |
|
1571
2d127394260e
6916623: Align object to 16 bytes to use Compressed Oops with java heap up to 64Gb
kvn
parents:
1165
diff
changeset
|
43 size_t hdr_size = oopDesc::header_size(); |
|
1165
2dd52dea6d28
6902115: G1:assert(ignore_max_completed||thread->is_Java_thread()||SafepointSynchronize::is_at_safepoint())
johnc
parents:
0
diff
changeset
|
44 Copy::fill_to_words(obj + hdr_size, size - hdr_size, badHeapWordVal); |
|
2dd52dea6d28
6902115: G1:assert(ignore_max_completed||thread->is_Java_thread()||SafepointSynchronize::is_at_safepoint())
johnc
parents:
0
diff
changeset
|
45 #endif // ASSERT |
| 0 | 46 // This addition is safe because we know that top is |
| 47 // at least size below end, so the add can't wrap. | |
| 48 set_top(obj + size); | |
| 49 | |
| 50 invariants(); | |
| 51 return obj; | |
| 52 } | |
| 53 return NULL; | |
| 54 } | |
| 55 | |
| 56 inline size_t ThreadLocalAllocBuffer::compute_size(size_t obj_size) { | |
| 57 const size_t aligned_obj_size = align_object_size(obj_size); | |
| 58 | |
| 59 // Compute the size for the new TLAB. | |
| 60 // The "last" tlab may be smaller to reduce fragmentation. | |
| 61 // unsafe_max_tlab_alloc is just a hint. | |
| 62 const size_t available_size = Universe::heap()->unsafe_max_tlab_alloc(myThread()) / | |
| 63 HeapWordSize; | |
| 64 size_t new_tlab_size = MIN2(available_size, desired_size() + aligned_obj_size); | |
| 65 | |
| 66 // Make sure there's enough room for object and filler int[]. | |
| 67 const size_t obj_plus_filler_size = aligned_obj_size + alignment_reserve(); | |
| 68 if (new_tlab_size < obj_plus_filler_size) { | |
| 69 // If there isn't enough room for the allocation, return failure. | |
| 70 if (PrintTLAB && Verbose) { | |
| 71 gclog_or_tty->print_cr("ThreadLocalAllocBuffer::compute_size(" SIZE_FORMAT ")" | |
| 72 " returns failure", | |
| 73 obj_size); | |
| 74 } | |
| 75 return 0; | |
| 76 } | |
| 77 if (PrintTLAB && Verbose) { | |
| 78 gclog_or_tty->print_cr("ThreadLocalAllocBuffer::compute_size(" SIZE_FORMAT ")" | |
| 79 " returns " SIZE_FORMAT, | |
| 80 obj_size, new_tlab_size); | |
| 81 } | |
| 82 return new_tlab_size; | |
| 83 } | |
| 84 | |
| 85 | |
| 86 void ThreadLocalAllocBuffer::record_slow_allocation(size_t obj_size) { | |
| 87 // Raise size required to bypass TLAB next time. Why? Else there's | |
| 88 // a risk that a thread that repeatedly allocates objects of one | |
| 89 // size will get stuck on this slow path. | |
| 90 | |
| 91 set_refill_waste_limit(refill_waste_limit() + refill_waste_limit_increment()); | |
| 92 | |
| 93 _slow_allocations++; | |
| 94 | |
| 95 if (PrintTLAB && Verbose) { | |
| 96 Thread* thrd = myThread(); | |
| 97 gclog_or_tty->print("TLAB: %s thread: "INTPTR_FORMAT" [id: %2d]" | |
| 98 " obj: "SIZE_FORMAT | |
| 99 " free: "SIZE_FORMAT | |
| 100 " waste: "SIZE_FORMAT"\n", | |
| 101 "slow", thrd, thrd->osthread()->thread_id(), | |
| 102 obj_size, free(), refill_waste_limit()); | |
| 103 } | |
| 104 } | |
| 1972 | 105 |
| 106 #endif // SHARE_VM_MEMORY_THREADLOCALALLOCBUFFER_INLINE_HPP |