1 /*
   2  * Copyright (c) 2005, 2020, 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 OS_LINUX_GLOBALS_LINUX_HPP
  26 #define OS_LINUX_GLOBALS_LINUX_HPP
  27 
  28 //
  29 // Defines Linux specific flags. They are not available on other platforms.
  30 //
  31 #define RUNTIME_OS_FLAGS(develop, \
  32                          develop_pd, \
  33                          product, \
  34                          product_pd, \
  35                          diagnostic, \
  36                          diagnostic_pd, \
  37                          notproduct, \
  38                          range, \
  39                          constraint) \
  40                                                                         \
  41   product(bool, UseOprofile, false,                                     \
  42         "enable support for Oprofile profiler")                         \
  43                                                                         \
  44   /*  NB: The default value of UseLinuxPosixThreadCPUClocks may be   */ \
  45   /* overridden in Arguments::parse_each_vm_init_arg.                */ \
  46   product(bool, UseLinuxPosixThreadCPUClocks, true,                     \
  47           "enable fast Linux Posix clocks where available")             \
  48                                                                         \
  49   product(bool, UseHugeTLBFS, false,                                    \
  50           "Use MAP_HUGETLB for large pages")                            \
  51                                                                         \
  52   product(bool, UseTransparentHugePages, false,                         \
  53           "Use MADV_HUGEPAGE for large pages")                          \
  54                                                                         \
  55   product(bool, LoadExecStackDllInVMThread, true,                       \
  56           "Load DLLs with executable-stack attribute in the VM Thread") \
  57                                                                         \
  58   product(bool, UseSHM, false,                                          \
  59           "Use SYSV shared memory for large pages")                     \
  60                                                                         \
  61   product(bool, UseContainerSupport, true,                              \
  62           "Enable detection and runtime container configuration support") \
  63                                                                         \
  64   product(bool, PreferContainerQuotaForCPUCount, true,                  \
  65           "Calculate the container CPU availability based on the value" \
  66           " of quotas (if set), when true. Otherwise, use the CPU"      \
  67           " shares value, provided it is less than quota.")             \
  68                                                                         \
  69   product(bool, AdjustStackSizeForTLS, false,                           \
  70           "Increase the thread stack size to include space for glibc "  \
  71           "static thread-local storage (TLS) if true")                  \
  72                                                                         \
  73   diagnostic(bool, DumpPrivateMappingsInCore, true,                     \
  74           "If true, sets bit 2 of /proc/PID/coredump_filter, thus "     \
  75           "resulting in file-backed private mappings of the process to "\
  76           "be dumped into the corefile.")                               \
  77                                                                         \
  78   diagnostic(bool, DumpSharedMappingsInCore, true,                      \
  79           "If true, sets bit 3 of /proc/PID/coredump_filter, thus "     \
  80           "resulting in file-backed shared mappings of the process to " \
  81           "be dumped into the corefile.")                               \
  82                                                                         \
  83   diagnostic(bool, UseCpuAllocPath, false,                              \
  84              "Use CPU_ALLOC code path in os::active_processor_count ")
  85 
  86 //
  87 // Defines Linux-specific default values. The flags are available on all
  88 // platforms, but they may have different default values on other platforms.
  89 //
  90 define_pd_global(bool, UseLargePages, false);
  91 define_pd_global(bool, UseLargePagesIndividualAllocation, false);
  92 define_pd_global(bool, UseOSErrorReporting, false);
  93 define_pd_global(bool, UseThreadPriorities, true) ;
  94 
  95 #endif // OS_LINUX_GLOBALS_LINUX_HPP