1 /*
   2  * Copyright (c) 2015, 2016, 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 #ifndef SHARE_VM_LOGGING_LOGPREFIX_HPP
  25 #define SHARE_VM_LOGGING_LOGPREFIX_HPP
  26 
  27 #include "gc/shared/gcId.hpp"
  28 #include "logging/logTag.hpp"
  29 
  30 // Prefixes prepend each log message for a specified tagset with a given prefix.
  31 // These prefixes are written before the log message but after the log decorations.
  32 //
  33 // A prefix is defined as a function that takes a buffer (with some size) as argument.
  34 // This function will be called for each log message, and should write the prefix
  35 // to the given buffer. The function should return how many characters it wrote,
  36 // which should never exceed the given size.
  37 //
  38 // List of prefixes for specific tags and/or tagsets.
  39 // Syntax: LOG_PREFIX(<name of prefixer function>, LOG_TAGS(<chosen log tags>))
  40 // Where the prefixer function matches the following signature: size_t (*)(char*, size_t)
  41 #define LOG_PREFIX_LIST \
  42   LOG_PREFIX(GCId::print_prefix, LOG_TAGS(gc)) \
  43   LOG_PREFIX(GCId::print_prefix, LOG_TAGS(gc, age)) \
  44   LOG_PREFIX(GCId::print_prefix, LOG_TAGS(gc, alloc)) \
  45   LOG_PREFIX(GCId::print_prefix, LOG_TAGS(gc, barrier)) \
  46   LOG_PREFIX(GCId::print_prefix, LOG_TAGS(gc, classhisto)) \
  47   LOG_PREFIX(GCId::print_prefix, LOG_TAGS(gc, compaction)) \
  48   LOG_PREFIX(GCId::print_prefix, LOG_TAGS(gc, compaction, phases)) \
  49   LOG_PREFIX(GCId::print_prefix, LOG_TAGS(gc, cpu)) \
  50   LOG_PREFIX(GCId::print_prefix, LOG_TAGS(gc, ergo)) \
  51   LOG_PREFIX(GCId::print_prefix, LOG_TAGS(gc, ergo, cset)) \
  52   LOG_PREFIX(GCId::print_prefix, LOG_TAGS(gc, ergo, heap)) \
  53   LOG_PREFIX(GCId::print_prefix, LOG_TAGS(gc, ergo, ihop)) \
  54   LOG_PREFIX(GCId::print_prefix, LOG_TAGS(gc, heap)) \
  55   LOG_PREFIX(GCId::print_prefix, LOG_TAGS(gc, freelist)) \
  56   LOG_PREFIX(GCId::print_prefix, LOG_TAGS(gc, ihop)) \
  57   LOG_PREFIX(GCId::print_prefix, LOG_TAGS(gc, liveness)) \
  58   LOG_PREFIX(GCId::print_prefix, LOG_TAGS(gc, marking)) \
  59   LOG_PREFIX(GCId::print_prefix, LOG_TAGS(gc, metaspace)) \
  60   LOG_PREFIX(GCId::print_prefix, LOG_TAGS(gc, phases)) \
  61   LOG_PREFIX(GCId::print_prefix, LOG_TAGS(gc, phases, start)) \
  62   LOG_PREFIX(GCId::print_prefix, LOG_TAGS(gc, phases, task)) \
  63   LOG_PREFIX(GCId::print_prefix, LOG_TAGS(gc, plab)) \
  64   LOG_PREFIX(GCId::print_prefix, LOG_TAGS(gc, region)) \
  65   LOG_PREFIX(GCId::print_prefix, LOG_TAGS(gc, remset)) \
  66   LOG_PREFIX(GCId::print_prefix, LOG_TAGS(gc, ref)) \
  67   LOG_PREFIX(GCId::print_prefix, LOG_TAGS(gc, ref, start)) \
  68   LOG_PREFIX(GCId::print_prefix, LOG_TAGS(gc, start)) \
  69   LOG_PREFIX(GCId::print_prefix, LOG_TAGS(gc, sweep)) \
  70   LOG_PREFIX(GCId::print_prefix, LOG_TAGS(gc, task)) \
  71   LOG_PREFIX(GCId::print_prefix, LOG_TAGS(gc, task, start)) \
  72   LOG_PREFIX(GCId::print_prefix, LOG_TAGS(gc, task, stats)) \
  73   LOG_PREFIX(GCId::print_prefix, LOG_TAGS(gc, task, time)) \
  74   LOG_PREFIX(GCId::print_prefix, LOG_TAGS(gc, tlab))
  75 
  76 
  77 // The empty prefix, used when there's no prefix defined.
  78 template <LogTagType T0, LogTagType T1, LogTagType T2, LogTagType T3, LogTagType T4, LogTagType GuardTag = LogTag::__NO_TAG>
  79 struct LogPrefix : public AllStatic {
  80   STATIC_ASSERT(GuardTag == LogTag::__NO_TAG);
  81   static size_t prefix(char* buf, size_t len) {
  82     return 0;
  83   }
  84 };
  85 
  86 #define LOG_PREFIX(fn, ...) \
  87 template <> struct LogPrefix<__VA_ARGS__> { \
  88   static size_t prefix(char* buf, size_t len) { \
  89     DEBUG_ONLY(buf[0] = '\0';) \
  90     size_t ret = fn(buf, len); \
  91     assert(ret == strlen(buf), "Length mismatch ret (" SIZE_FORMAT ") != buf length (" SIZE_FORMAT ")", ret, strlen(buf)); \
  92     return ret; \
  93   } \
  94 };
  95 LOG_PREFIX_LIST
  96 #undef LOG_PREFIX
  97 
  98 #endif // SHARE_VM_LOGGING_LOGPREFIX_HPP