Mercurial > hg > graal-compiler
annotate src/share/vm/utilities/defaultStream.hpp @ 1711:a6bff45449bc
6973570: OrderAccess::storestore() scales poorly on multi-socket x64 and sparc: cache-line ping-ponging
Summary: volatile store to static variable removed in favour of a volatile store to stack to avoid excessive cache coherency traffic; verified that the volatile store is not elided by any of our current compilers.
Reviewed-by: dholmes, dice, jcoomes, kvn
author | ysr |
---|---|
date | Tue, 10 Aug 2010 14:53:35 -0700 |
parents | c18cbe5936b8 |
children | f95d63e2154a |
rev | line source |
---|---|
0 | 1 /* |
1552
c18cbe5936b8
6941466: Oracle rebranding changes for Hotspot repositories
trims
parents:
0
diff
changeset
|
2 * Copyright (c) 2003, 2004, 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:
0
diff
changeset
|
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
c18cbe5936b8
6941466: Oracle rebranding changes for Hotspot repositories
trims
parents:
0
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:
0
diff
changeset
|
21 * questions. |
0 | 22 * |
23 */ | |
24 | |
25 class defaultStream : public xmlTextStream { | |
26 friend void ostream_abort(); | |
27 public: | |
28 enum { NO_WRITER = -1 }; | |
29 private: | |
30 bool _inited; | |
31 fileStream* _log_file; // XML-formatted file shared by all threads | |
32 static int _output_fd; | |
33 static int _error_fd; | |
34 static FILE* _output_stream; | |
35 static FILE* _error_stream; | |
36 | |
37 void init(); | |
38 void init_log(); | |
39 void finish_log(); | |
40 void finish_log_on_error(char *buf, int buflen); | |
41 public: | |
42 // must defer time stamp due to the fact that os::init() hasn't | |
43 // yet been called and os::elapsed_counter() may not be valid | |
44 defaultStream() { | |
45 _log_file = NULL; | |
46 _inited = false; | |
47 _writer = -1; | |
48 _last_writer = -1; | |
49 } | |
50 | |
51 ~defaultStream() { | |
52 if (has_log_file()) finish_log(); | |
53 } | |
54 | |
55 static inline FILE* output_stream() { | |
56 return DisplayVMOutputToStderr ? _error_stream : _output_stream; | |
57 } | |
58 static inline FILE* error_stream() { | |
59 return DisplayVMOutputToStdout ? _output_stream : _error_stream; | |
60 } | |
61 static inline int output_fd() { | |
62 return DisplayVMOutputToStderr ? _error_fd : _output_fd; | |
63 } | |
64 static inline int error_fd() { | |
65 return DisplayVMOutputToStdout ? _output_fd : _error_fd; | |
66 } | |
67 | |
68 virtual void write(const char* s, size_t len); | |
69 | |
70 void flush() { | |
71 // once we can determine whether we are in a signal handler, we | |
72 // should add the following assert here: | |
73 // assert(xxxxxx, "can not flush buffer inside signal handler"); | |
74 xmlTextStream::flush(); | |
75 fflush(output_stream()); | |
76 if (has_log_file()) _log_file->flush(); | |
77 } | |
78 | |
79 // advisory lock/unlock of _writer field: | |
80 private: | |
81 intx _writer; // thread_id with current rights to output | |
82 intx _last_writer; | |
83 public: | |
84 intx hold(intx writer_id); | |
85 void release(intx holder); | |
86 intx writer() { return _writer; } | |
87 bool has_log_file(); | |
88 | |
89 static defaultStream* instance; // sole instance | |
90 }; |