Wed, 01 Feb 2012 07:59:01 -0800
7141200: log some interesting information in ring buffers for crashes
Reviewed-by: kvn, jrose, kevinw, brutisso, twisti, jmasa
1 /*
2 * Copyright (c) 2002, 2010, 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.
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23 */
25 #include "precompiled.hpp"
26 #include "ci/ciMethod.hpp"
27 #include "compiler/compileLog.hpp"
28 #include "memory/allocation.inline.hpp"
29 #include "oops/methodOop.hpp"
30 #include "runtime/mutexLocker.hpp"
31 #include "runtime/os.hpp"
33 CompileLog* CompileLog::_first = NULL;
35 // ------------------------------------------------------------------
36 // CompileLog::CompileLog
37 CompileLog::CompileLog(const char* file, FILE* fp, intx thread_id)
38 : _context(_context_buffer, sizeof(_context_buffer))
39 {
40 initialize(new(ResourceObj::C_HEAP) fileStream(fp));
41 _file = file;
42 _file_end = 0;
43 _thread_id = thread_id;
45 _identities_limit = 0;
46 _identities_capacity = 400;
47 _identities = NEW_C_HEAP_ARRAY(char, _identities_capacity);
49 // link into the global list
50 { MutexLocker locker(CompileTaskAlloc_lock);
51 _next = _first;
52 _first = this;
53 }
54 }
56 CompileLog::~CompileLog() {
57 delete _out;
58 _out = NULL;
59 FREE_C_HEAP_ARRAY(char, _identities);
60 }
63 // Advance kind up to a null or space, return this tail.
64 // Make sure kind is null-terminated, not space-terminated.
65 // Use the buffer if necessary.
66 static const char* split_attrs(const char* &kind, char* buffer) {
67 const char* attrs = strchr(kind, ' ');
68 // Tease apart the first word from the rest:
69 if (attrs == NULL) {
70 return ""; // no attrs, no split
71 } else if (kind == buffer) {
72 ((char*) attrs)[-1] = 0;
73 return attrs;
74 } else {
75 // park it in the buffer, so we can put a null on the end
76 assert(!(kind >= buffer && kind < buffer+100), "not obviously in buffer");
77 int klen = attrs - kind;
78 strncpy(buffer, kind, klen);
79 buffer[klen] = 0;
80 kind = buffer; // return by reference
81 return attrs;
82 }
83 }
85 // see_tag, pop_tag: Override the default do-nothing methods on xmlStream.
86 // These methods provide a hook for managing the the extra context markup.
87 void CompileLog::see_tag(const char* tag, bool push) {
88 if (_context.size() > 0 && _out != NULL) {
89 _out->write(_context.base(), _context.size());
90 _context.reset();
91 }
92 xmlStream::see_tag(tag, push);
93 }
94 void CompileLog::pop_tag(const char* tag) {
95 _context.reset(); // toss any context info.
96 xmlStream::pop_tag(tag);
97 }
100 // ------------------------------------------------------------------
101 // CompileLog::identify
102 int CompileLog::identify(ciObject* obj) {
103 if (obj == NULL) return 0;
104 int id = obj->ident();
105 if (id < 0) return id;
106 // If it has already been identified, just return the id.
107 if (id < _identities_limit && _identities[id] != 0) return id;
108 // Lengthen the array, if necessary.
109 if (id >= _identities_capacity) {
110 int new_cap = _identities_capacity * 2;
111 if (new_cap <= id) new_cap = id + 100;
112 _identities = REALLOC_C_HEAP_ARRAY(char, _identities, new_cap);
113 _identities_capacity = new_cap;
114 }
115 while (id >= _identities_limit) {
116 _identities[_identities_limit++] = 0;
117 }
118 assert(id < _identities_limit, "oob");
119 // Mark this id as processed.
120 // (Be sure to do this before any recursive calls to identify.)
121 _identities[id] = 1; // mark
123 // Now, print the object's identity once, in detail.
124 if (obj->is_klass()) {
125 ciKlass* klass = obj->as_klass();
126 begin_elem("klass id='%d'", id);
127 name(klass->name());
128 if (!klass->is_loaded()) {
129 print(" unloaded='1'");
130 } else {
131 print(" flags='%d'", klass->modifier_flags());
132 }
133 end_elem();
134 } else if (obj->is_method()) {
135 ciMethod* method = obj->as_method();
136 ciSignature* sig = method->signature();
137 // Pre-identify items that we will need!
138 identify(sig->return_type());
139 for (int i = 0; i < sig->count(); i++) {
140 identify(sig->type_at(i));
141 }
142 begin_elem("method id='%d' holder='%d'",
143 id, identify(method->holder()));
144 name(method->name());
145 print(" return='%d'", identify(sig->return_type()));
146 if (sig->count() > 0) {
147 print(" arguments='");
148 for (int i = 0; i < sig->count(); i++) {
149 print((i == 0) ? "%d" : " %d", identify(sig->type_at(i)));
150 }
151 print("'");
152 }
153 if (!method->is_loaded()) {
154 print(" unloaded='1'");
155 } else {
156 print(" flags='%d'", (jchar) method->flags().as_int());
157 // output a few metrics
158 print(" bytes='%d'", method->code_size());
159 method->log_nmethod_identity(this);
160 //print(" count='%d'", method->invocation_count());
161 //int bec = method->backedge_count();
162 //if (bec != 0) print(" backedge_count='%d'", bec);
163 print(" iicount='%d'", method->interpreter_invocation_count());
164 }
165 end_elem();
166 } else if (obj->is_symbol()) {
167 begin_elem("symbol id='%d'", id);
168 name(obj->as_symbol());
169 end_elem();
170 } else if (obj->is_null_object()) {
171 elem("null_object id='%d'", id);
172 } else if (obj->is_type()) {
173 BasicType type = obj->as_type()->basic_type();
174 elem("type id='%d' name='%s'", id, type2name(type));
175 } else {
176 // Should not happen.
177 elem("unknown id='%d'", id);
178 }
179 return id;
180 }
182 void CompileLog::name(ciSymbol* name) {
183 if (name == NULL) return;
184 print(" name='");
185 name->print_symbol_on(text()); // handles quoting conventions
186 print("'");
187 }
190 // ------------------------------------------------------------------
191 // CompileLog::clear_identities
192 // Forget which identities have been printed.
193 void CompileLog::clear_identities() {
194 _identities_limit = 0;
195 }
197 // ------------------------------------------------------------------
198 // CompileLog::finish_log_on_error
199 //
200 // Note: This function is called after fatal error, avoid unnecessary memory
201 // or stack allocation, use only async-safe functions. It's possible JVM is
202 // only partially initialized.
203 void CompileLog::finish_log_on_error(outputStream* file, char* buf, int buflen) {
204 static bool called_exit = false;
205 if (called_exit) return;
206 called_exit = true;
208 for (CompileLog* log = _first; log != NULL; log = log->_next) {
209 log->flush();
210 const char* partial_file = log->file();
211 int partial_fd = open(partial_file, O_RDONLY);
212 if (partial_fd != -1) {
213 // print/print_cr may need to allocate large stack buffer to format
214 // strings, here we use snprintf() and print_raw() instead.
215 file->print_raw("<compilation_log thread='");
216 jio_snprintf(buf, buflen, UINTX_FORMAT, log->thread_id());
217 file->print_raw(buf);
218 file->print_raw_cr("'>");
220 size_t nr; // number read into buf from partial log
221 // Copy data up to the end of the last <event> element:
222 julong to_read = log->_file_end;
223 while (to_read > 0) {
224 if (to_read < (julong)buflen)
225 nr = (size_t)to_read;
226 else nr = buflen;
227 nr = read(partial_fd, buf, (int)nr);
228 if (nr <= 0) break;
229 to_read -= (julong)nr;
230 file->write(buf, nr);
231 }
233 // Copy any remaining data inside a quote:
234 bool saw_slop = false;
235 int end_cdata = 0; // state machine [0..2] watching for too many "]]"
236 while ((nr = read(partial_fd, buf, buflen)) > 0) {
237 if (!saw_slop) {
238 file->print_raw_cr("<fragment>");
239 file->print_raw_cr("<![CDATA[");
240 saw_slop = true;
241 }
242 // The rest of this loop amounts to a simple copy operation:
243 // { file->write(buf, nr); }
244 // However, it must sometimes output the buffer in parts,
245 // in case there is a CDATA quote embedded in the fragment.
246 const char* bufp; // pointer into buf
247 size_t nw; // number written in each pass of the following loop:
248 for (bufp = buf; nr > 0; nr -= nw, bufp += nw) {
249 // Write up to any problematic CDATA delimiter (usually all of nr).
250 for (nw = 0; nw < nr; nw++) {
251 // First, scan ahead into the buf, checking the state machine.
252 switch (bufp[nw]) {
253 case ']':
254 if (end_cdata < 2) end_cdata += 1; // saturating counter
255 continue; // keep scanning
256 case '>':
257 if (end_cdata == 2) break; // found CDATA delimiter!
258 // else fall through:
259 default:
260 end_cdata = 0;
261 continue; // keep scanning
262 }
263 // If we get here, nw is pointing at a bad '>'.
264 // It is very rare for this to happen.
265 // However, this code has been tested by introducing
266 // CDATA sequences into the compilation log.
267 break;
268 }
269 // Now nw is the number of characters to write, usually == nr.
270 file->write(bufp, nw);
271 if (nw < nr) {
272 // We are about to go around the loop again.
273 // But first, disrupt the ]]> by closing and reopening the quote.
274 file->print_raw("]]><![CDATA[");
275 end_cdata = 0; // reset state machine
276 }
277 }
278 }
279 if (saw_slop) {
280 file->print_raw_cr("]]>");
281 file->print_raw_cr("</fragment>");
282 }
283 file->print_raw_cr("</compilation_log>");
284 close(partial_fd);
285 unlink(partial_file);
286 }
287 }
288 }
290 // ------------------------------------------------------------------
291 // CompileLog::finish_log
292 //
293 // Called during normal shutdown. For now, any clean-up needed in normal
294 // shutdown is also needed in VM abort, so is covered by finish_log_on_error().
295 // Just allocate a buffer and call finish_log_on_error().
296 void CompileLog::finish_log(outputStream* file) {
297 char buf[4 * K];
298 finish_log_on_error(file, buf, sizeof(buf));
299 }