openjdk/src/hotspot/os/linux/globals_linux.hpp
David Holmes ef45c8154c 8346237: Obsolete the UseOprofile flag
Reviewed-by: coleenp, kvn
2025-06-09 20:59:30 +00:00

104 lines
6.0 KiB
C++

/*
* Copyright (c) 2005, 2025, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*
*/
#ifndef OS_LINUX_GLOBALS_LINUX_HPP
#define OS_LINUX_GLOBALS_LINUX_HPP
//
// Declare Linux specific flags. They are not available on other platforms.
//
#define RUNTIME_OS_FLAGS(develop, \
develop_pd, \
product, \
product_pd, \
range, \
constraint) \
\
product(bool, UseTransparentHugePages, false, \
"Use MADV_HUGEPAGE for large pages") \
\
product(bool, LoadExecStackDllInVMThread, true, \
"Load DLLs with executable-stack attribute in the VM Thread") \
\
product(bool, UseContainerSupport, true, \
"Enable detection and runtime container configuration support") \
\
product(bool, AdjustStackSizeForTLS, false, \
"Increase the thread stack size to include space for glibc " \
"static thread-local storage (TLS) if true") \
\
product(bool, DumpPrivateMappingsInCore, true, DIAGNOSTIC, \
"If true, sets bit 2 of /proc/PID/coredump_filter, thus " \
"resulting in file-backed private mappings of the process to "\
"be dumped into the corefile.") \
\
product(bool, DumpSharedMappingsInCore, true, DIAGNOSTIC, \
"If true, sets bit 3 of /proc/PID/coredump_filter, thus " \
"resulting in file-backed shared mappings of the process to " \
"be dumped into the corefile.") \
\
product(bool, UseCpuAllocPath, false, DIAGNOSTIC, \
"Use CPU_ALLOC code path in os::active_processor_count ") \
\
product(bool, DumpPerfMapAtExit, false, DIAGNOSTIC, \
"Write map file for Linux perf tool at exit") \
\
product(intx, TimerSlack, -1, EXPERIMENTAL, \
"Overrides the timer slack value to the given number of " \
"nanoseconds. Lower value provides more accurate " \
"high-precision timers, at the expense of (possibly) worse " \
"power efficiency. In current Linux, 0 means using the " \
"system-wide default, which would disable the override, but " \
"VM would still print the current timer slack values. Use -1 "\
"to disable both the override and the printouts." \
"See prctl(PR_SET_TIMERSLACK) for more info.") \
\
product(bool, THPStackMitigation, true, DIAGNOSTIC, \
"If THPs are unconditionally enabled on the system (mode " \
"\"always\"), the JVM will prevent THP from forming in " \
"thread stacks. When disabled, the absence of this mitigation"\
"allows THPs to form in thread stacks.") \
\
develop(bool, DelayThreadStartALot, false, \
"Artificially delay thread starts randomly for testing.") \
\
product(bool, UseMadvPopulateWrite, true, DIAGNOSTIC, \
"Use MADV_POPULATE_WRITE in os::pd_pretouch_memory.") \
\
product(bool, PrintMemoryMapAtExit, false, DIAGNOSTIC, \
"Print an annotated memory map at exit") \
\
// end of RUNTIME_OS_FLAGS
//
// Defines Linux-specific default values. The flags are available on all
// platforms, but they may have different default values on other platforms.
//
define_pd_global(size_t, PreTouchParallelChunkSize, 4 * M);
define_pd_global(bool, UseLargePages, false);
define_pd_global(bool, UseLargePagesIndividualAllocation, false);
define_pd_global(bool, UseThreadPriorities, true) ;
#endif // OS_LINUX_GLOBALS_LINUX_HPP