--- old/src/hotspot/os/bsd/gc/z/zBackingFile_bsd.cpp 2020-01-15 13:47:31.862331106 +0100 +++ new/src/hotspot/os/bsd/gc/z/zBackingFile_bsd.cpp 2020-01-15 13:47:31.573325225 +0100 @@ -89,6 +89,10 @@ return _initialized; } +void ZBackingFile::warn_commit_limits(size_t max) const { + // Does nothing +} + size_t ZBackingFile::size() const { return _size; } --- old/src/hotspot/os/bsd/gc/z/zBackingFile_bsd.hpp 2020-01-15 13:47:32.308340182 +0100 +++ new/src/hotspot/os/bsd/gc/z/zBackingFile_bsd.hpp 2020-01-15 13:47:31.967333243 +0100 @@ -47,6 +47,8 @@ bool is_initialized() const; + void warn_commit_limits(size_t max) const; + size_t size() const; size_t commit(size_t offset, size_t length); --- old/src/hotspot/os/linux/gc/z/zBackingFile_linux.cpp 2020-01-15 13:47:32.753349238 +0100 +++ new/src/hotspot/os/linux/gc/z/zBackingFile_linux.cpp 2020-01-15 13:47:32.419342441 +0100 @@ -36,6 +36,7 @@ #include "utilities/debug.hpp" #include +#include #include #include #include @@ -82,6 +83,9 @@ #define ZFILESYSTEM_TMPFS "tmpfs" #define ZFILESYSTEM_HUGETLBFS "hugetlbfs" +// Proc file entry for max map mount +#define ZFILENAME_PROC_MAX_MAP_COUNT "/proc/sys/vm/max_map_count" + // Sysfs file for transparent huge page on tmpfs #define ZFILENAME_SHMEM_ENABLED "/sys/kernel/mm/transparent_hugepage/shmem_enabled" @@ -278,16 +282,76 @@ return _initialized; } -int ZBackingFile::fd() const { - return _fd; +void ZBackingFile::warn_available_space(size_t max) const { + // Note that the available space on a tmpfs or a hugetlbfs filesystem + // will be zero if no size limit was specified when it was mounted. + if (_available == 0) { + // No size limit set, skip check + log_info(gc, init)("Available space on backing filesystem: N/A"); + return; + } + + log_info(gc, init)("Available space on backing filesystem: " SIZE_FORMAT "M", _available / M); + + // Warn if the filesystem doesn't currently have enough space available to hold + // the max heap size. The max heap size will be capped if we later hit this limit + // when trying to expand the heap. + if (_available < max) { + log_warning(gc)("***** WARNING! INCORRECT SYSTEM CONFIGURATION DETECTED! *****"); + log_warning(gc)("Not enough space available on the backing filesystem to hold the current max Java heap"); + log_warning(gc)("size (" SIZE_FORMAT "M). Please adjust the size of the backing filesystem accordingly " + "(available", max / M); + log_warning(gc)("space is currently " SIZE_FORMAT "M). Continuing execution with the current filesystem " + "size could", _available / M); + log_warning(gc)("lead to a premature OutOfMemoryError being thrown, due to failure to map memory."); + } } -size_t ZBackingFile::size() const { - return _size; +void ZBackingFile::warn_max_map_count(size_t max) const { + const char* const filename = ZFILENAME_PROC_MAX_MAP_COUNT; + FILE* const file = fopen(filename, "r"); + if (file == NULL) { + // Failed to open file, skip check + log_debug(gc, init)("Failed to open %s", filename); + return; + } + + size_t actual_max_map_count = 0; + const int result = fscanf(file, SIZE_FORMAT, &actual_max_map_count); + fclose(file); + if (result != 1) { + // Failed to read file, skip check + log_debug(gc, init)("Failed to read %s", filename); + return; + } + + // The required max map count is impossible to calculate exactly since subsystems + // other than ZGC are also creating memory mappings, and we have no control over that. + // However, ZGC tends to create the most mappings and dominate the total count. + // In the worst cases, ZGC will map each granule three times, i.e. once per heap view. + // We speculate that we need another 20% to allow for non-ZGC subsystems to map memory. + const size_t required_max_map_count = (max / ZGranuleSize) * 3 * 1.2; + if (actual_max_map_count < required_max_map_count) { + log_warning(gc)("***** WARNING! INCORRECT SYSTEM CONFIGURATION DETECTED! *****"); + log_warning(gc)("The system limit on number of memory mappings per process might be too low for the given"); + log_warning(gc)("max Java heap size (" SIZE_FORMAT "M). Please adjust %s to allow for at", + max / M, filename); + log_warning(gc)("least " SIZE_FORMAT " mappings (current limit is " SIZE_FORMAT "). Continuing execution " + "with the current", required_max_map_count, actual_max_map_count); + log_warning(gc)("limit could lead to a fatal error, due to failure to map memory."); + } } -size_t ZBackingFile::available() const { - return _available; +void ZBackingFile::warn_commit_limits(size_t max) const { + // Warn if available space is too low + warn_available_space(max); + + // Warn if max map count is too low + warn_max_map_count(max); +} + +size_t ZBackingFile::size() const { + return _size; } bool ZBackingFile::is_tmpfs() const { @@ -572,3 +636,22 @@ return length; } + +void ZBackingFile::map(uintptr_t addr, size_t size, uintptr_t offset) const { + const void* const res = mmap((void*)addr, size, PROT_READ|PROT_WRITE, MAP_FIXED|MAP_SHARED, _fd, offset); + if (res == MAP_FAILED) { + ZErrno err; + fatal("Failed to map memory (%s)", err.to_string()); + } +} + +void ZBackingFile::unmap(uintptr_t addr, size_t size) const { + // Note that we must keep the address space reservation intact and just detach + // the backing memory. For this reason we map a new anonymous, non-accessible + // and non-reserved page over the mapping instead of actually unmapping. + const void* const res = mmap((void*)addr, size, PROT_NONE, MAP_FIXED | MAP_ANONYMOUS | MAP_PRIVATE | MAP_NORESERVE, -1, 0); + if (res == MAP_FAILED) { + ZErrno err; + fatal("Failed to map memory (%s)", err.to_string()); + } +} --- old/src/hotspot/os/linux/gc/z/zBackingFile_linux.hpp 2020-01-15 13:47:33.233359006 +0100 +++ new/src/hotspot/os/linux/gc/z/zBackingFile_linux.hpp 2020-01-15 13:47:32.878351781 +0100 @@ -37,6 +37,9 @@ size_t _available; bool _initialized; + void warn_available_space(size_t max) const; + void warn_max_map_count(size_t max) const; + int create_mem_fd(const char* name) const; int create_file_fd(const char* name) const; int create_fd(const char* name) const; @@ -62,12 +65,15 @@ bool is_initialized() const; - int fd() const; + void warn_commit_limits(size_t max) const; + size_t size() const; - size_t available() const; size_t commit(size_t offset, size_t length); size_t uncommit(size_t offset, size_t length); + + void map(uintptr_t addr, size_t size, uintptr_t offset) const; + void unmap(uintptr_t addr, size_t size) const; }; #endif // OS_LINUX_GC_Z_ZBACKINGFILE_LINUX_HPP --- old/src/hotspot/os/windows/gc/z/zBackingFile_windows.cpp 2020-01-15 13:47:33.627367023 +0100 +++ new/src/hotspot/os/windows/gc/z/zBackingFile_windows.cpp 2020-01-15 13:47:33.338361142 +0100 @@ -39,6 +39,14 @@ _handles(MaxHeapSize), _size(0) {} +bool ZBackingFile::is_initialized() const { + return true; +} + +void ZBackingFile::warn_commit_limits(size_t max) const { + // Does nothing +} + size_t ZBackingFile::size() const { return _size; } --- old/src/hotspot/os/windows/gc/z/zBackingFile_windows.hpp 2020-01-15 13:47:34.087376384 +0100 +++ new/src/hotspot/os/windows/gc/z/zBackingFile_windows.hpp 2020-01-15 13:47:33.731369140 +0100 @@ -44,6 +44,10 @@ public: ZBackingFile(); + bool is_initialized() const; + + void warn_commit_limits(size_t max) const; + size_t size() const; size_t commit(size_t offset, size_t length); --- old/src/hotspot/share/gc/z/zNUMA.cpp 2020-01-15 13:47:34.479384361 +0100 +++ new/src/hotspot/share/gc/z/zNUMA.cpp 2020-01-15 13:47:34.189378460 +0100 @@ -1,5 +1,5 @@ /* - * Copyright (c) 2016, 2017, Oracle and/or its affiliates. All rights reserved. + * Copyright (c) 2016, 2019, 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 @@ -32,24 +32,11 @@ initialize_platform(); log_info(gc, init)("NUMA Support: %s", to_string()); - if (is_enabled()) { + if (_enabled) { log_info(gc, init)("NUMA Nodes: %u", count()); } } -bool ZNUMA::is_enabled() { - return _enabled; -} - -void ZNUMA::memory_interleave(uintptr_t addr, size_t size) { - if (!_enabled) { - // NUMA support not enabled - return; - } - - os::numa_make_global((char*)addr, size); -} - const char* ZNUMA::to_string() { return _enabled ? "Enabled" : "Disabled"; } --- old/src/hotspot/share/gc/z/zNUMA.hpp 2020-01-15 13:47:34.871392339 +0100 +++ new/src/hotspot/share/gc/z/zNUMA.hpp 2020-01-15 13:47:34.583386478 +0100 @@ -1,5 +1,5 @@ /* - * Copyright (c) 2016, 2017, Oracle and/or its affiliates. All rights reserved. + * Copyright (c) 2016, 2019, 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 @@ -40,7 +40,6 @@ static uint32_t id(); static uint32_t memory_id(uintptr_t addr); - static void memory_interleave(uintptr_t addr, size_t size); static const char* to_string(); }; --- old/src/hotspot/share/gc/z/zPhysicalMemory.cpp 2020-01-15 13:47:35.334401761 +0100 +++ new/src/hotspot/share/gc/z/zPhysicalMemory.cpp 2020-01-15 13:47:34.976394475 +0100 @@ -22,10 +22,15 @@ */ #include "precompiled.hpp" +#include "gc/z/zAddress.inline.hpp" +#include "gc/z/zGlobals.hpp" +#include "gc/z/zLargePages.inline.hpp" +#include "gc/z/zNUMA.inline.hpp" #include "gc/z/zPhysicalMemory.inline.hpp" -#include "logging/log.hpp" -#include "memory/allocation.inline.hpp" +#include "runtime/init.hpp" +#include "runtime/os.hpp" #include "services/memTracker.hpp" +#include "utilities/align.hpp" #include "utilities/debug.hpp" #include "utilities/globalDefinitions.hpp" @@ -139,18 +144,23 @@ } bool ZPhysicalMemoryManager::supports_uncommit() { - return _backing.supports_uncommit(); + assert(!is_init_completed(), "Invalid state"); + assert(_backing.size() >= ZGranuleSize, "Invalid size"); + + // Test if uncommit is supported by uncommitting and then re-committing a granule + return commit(uncommit(ZGranuleSize)) == ZGranuleSize; } void ZPhysicalMemoryManager::nmt_commit(const ZPhysicalMemory& pmem, uintptr_t offset) const { - const uintptr_t addr = _backing.nmt_address(offset); + // From an NMT point of view we treat the first heap view (marked0) as committed + const uintptr_t addr = ZAddress::marked0(offset); const size_t size = pmem.size(); MemTracker::record_virtual_memory_commit((void*)addr, size, CALLER_PC); } void ZPhysicalMemoryManager::nmt_uncommit(const ZPhysicalMemory& pmem, uintptr_t offset) const { if (MemTracker::tracking_level() > NMT_minimal) { - const uintptr_t addr = _backing.nmt_address(offset); + const uintptr_t addr = ZAddress::marked0(offset); const size_t size = pmem.size(); Tracker tracker(Tracker::uncommit); tracker.record((address)addr, size); @@ -158,39 +168,178 @@ } size_t ZPhysicalMemoryManager::commit(size_t size) { - return _backing.commit(size); + size_t committed = 0; + + // Fill holes in the backing memory + while (committed < size) { + size_t allocated = 0; + const size_t remaining = size - committed; + const uintptr_t start = _uncommitted.alloc_from_front_at_most(remaining, &allocated); + if (start == UINTPTR_MAX) { + // No holes to commit + break; + } + + // Try commit hole + const size_t filled = _backing.commit(start, allocated); + if (filled > 0) { + // Successful or partialy successful + _committed.free(start, filled); + committed += filled; + } + if (filled < allocated) { + // Failed or partialy failed + _uncommitted.free(start + filled, allocated - filled); + return committed; + } + } + + // Expand backing memory + if (committed < size) { + const size_t remaining = size - committed; + const uintptr_t start = _backing.size(); + const size_t expanded = _backing.commit(start, remaining); + if (expanded > 0) { + // Successful or partialy successful + _committed.free(start, expanded); + committed += expanded; + } + } + + return committed; } size_t ZPhysicalMemoryManager::uncommit(size_t size) { - return _backing.uncommit(size); + size_t uncommitted = 0; + + // Punch holes in backing memory + while (uncommitted < size) { + size_t allocated = 0; + const size_t remaining = size - uncommitted; + const uintptr_t start = _committed.alloc_from_back_at_most(remaining, &allocated); + assert(start != UINTPTR_MAX, "Allocation should never fail"); + + // Try punch hole + const size_t punched = _backing.uncommit(start, allocated); + if (punched > 0) { + // Successful or partialy successful + _uncommitted.free(start, punched); + uncommitted += punched; + } + if (punched < allocated) { + // Failed or partialy failed + _committed.free(start + punched, allocated - punched); + return uncommitted; + } + } + + return uncommitted; } ZPhysicalMemory ZPhysicalMemoryManager::alloc(size_t size) { - return _backing.alloc(size); + assert(is_aligned(size, ZGranuleSize), "Invalid size"); + + ZPhysicalMemory pmem; + + // Allocate segments + for (size_t allocated = 0; allocated < size; allocated += ZGranuleSize) { + const uintptr_t start = _committed.alloc_from_front(ZGranuleSize); + assert(start != UINTPTR_MAX, "Allocation should never fail"); + pmem.add_segment(ZPhysicalMemorySegment(start, ZGranuleSize)); + } + + return pmem; } void ZPhysicalMemoryManager::free(const ZPhysicalMemory& pmem) { - _backing.free(pmem); + const size_t nsegments = pmem.nsegments(); + + // Free segments + for (size_t i = 0; i < nsegments; i++) { + const ZPhysicalMemorySegment& segment = pmem.segment(i); + _committed.free(segment.start(), segment.size()); + } +} + +void ZPhysicalMemoryManager::pretouch_view(uintptr_t addr, size_t size) const { + const size_t page_size = ZLargePages::is_explicit() ? ZGranuleSize : os::vm_page_size(); + os::pretouch_memory((void*)addr, (void*)(addr + size), page_size); +} + +void ZPhysicalMemoryManager::map_view(const ZPhysicalMemory& pmem, uintptr_t addr) const { + const size_t nsegments = pmem.nsegments(); + size_t size = 0; + + // Map segments + for (size_t i = 0; i < nsegments; i++) { + const ZPhysicalMemorySegment& segment = pmem.segment(i); + _backing.map(addr + size, segment.size(), segment.start()); + size += segment.size(); + } + + // Setup NUMA interleaving + if (ZNUMA::is_enabled()) { + os::numa_make_global((char*)addr, size); + } + + // Setup transparent large pages + if (ZLargePages::is_transparent()) { + os::realign_memory((char*)addr, size, os::large_page_size()); + } +} + +void ZPhysicalMemoryManager::unmap_view(const ZPhysicalMemory& pmem, uintptr_t addr) const { + _backing.unmap(addr, pmem.size()); } void ZPhysicalMemoryManager::pretouch(uintptr_t offset, size_t size) const { - _backing.pretouch(offset, size); + if (ZVerifyViews) { + // Pre-touch good view + pretouch_view(ZAddress::good(offset), size); + } else { + // Pre-touch all views + pretouch_view(ZAddress::marked0(offset), size); + pretouch_view(ZAddress::marked1(offset), size); + pretouch_view(ZAddress::remapped(offset), size); + } } void ZPhysicalMemoryManager::map(const ZPhysicalMemory& pmem, uintptr_t offset) const { - _backing.map(pmem, offset); + if (ZVerifyViews) { + // Map good view + map_view(pmem, ZAddress::good(offset)); + } else { + // Map all views + map_view(pmem, ZAddress::marked0(offset)); + map_view(pmem, ZAddress::marked1(offset)); + map_view(pmem, ZAddress::remapped(offset)); + } + nmt_commit(pmem, offset); } void ZPhysicalMemoryManager::unmap(const ZPhysicalMemory& pmem, uintptr_t offset) const { nmt_uncommit(pmem, offset); - _backing.unmap(pmem, offset); + + if (ZVerifyViews) { + // Unmap good view + unmap_view(pmem, ZAddress::good(offset)); + } else { + // Unmap all views + unmap_view(pmem, ZAddress::marked0(offset)); + unmap_view(pmem, ZAddress::marked1(offset)); + unmap_view(pmem, ZAddress::remapped(offset)); + } } void ZPhysicalMemoryManager::debug_map(const ZPhysicalMemory& pmem, uintptr_t offset) const { - _backing.debug_map(pmem, offset); + // Map good view + assert(ZVerifyViews, "Should be enabled"); + map_view(pmem, ZAddress::good(offset)); } void ZPhysicalMemoryManager::debug_unmap(const ZPhysicalMemory& pmem, uintptr_t offset) const { - _backing.debug_unmap(pmem, offset); + // Unmap good view + assert(ZVerifyViews, "Should be enabled"); + unmap_view(pmem, ZAddress::good(offset)); } --- old/src/hotspot/share/gc/z/zPhysicalMemory.hpp 2020-01-15 13:47:35.735409921 +0100 +++ new/src/hotspot/share/gc/z/zPhysicalMemory.hpp 2020-01-15 13:47:35.450404121 +0100 @@ -24,8 +24,9 @@ #ifndef SHARE_GC_Z_ZPHYSICALMEMORY_HPP #define SHARE_GC_Z_ZPHYSICALMEMORY_HPP +#include "gc/z/zMemory.hpp" #include "memory/allocation.hpp" -#include OS_HEADER(gc/z/zPhysicalMemoryBacking) +#include OS_HEADER(gc/z/zBackingFile) class ZPhysicalMemorySegment : public CHeapObj { private: @@ -65,11 +66,17 @@ class ZPhysicalMemoryManager { private: - ZPhysicalMemoryBacking _backing; + ZBackingFile _backing; + ZMemoryManager _committed; + ZMemoryManager _uncommitted; void nmt_commit(const ZPhysicalMemory& pmem, uintptr_t offset) const; void nmt_uncommit(const ZPhysicalMemory& pmem, uintptr_t offset) const; + void pretouch_view(uintptr_t addr, size_t size) const; + void map_view(const ZPhysicalMemory& pmem, uintptr_t addr) const; + void unmap_view(const ZPhysicalMemory& pmem, uintptr_t addr) const; + public: bool is_initialized() const; --- /dev/null 2020-01-07 09:26:22.747784373 +0100 +++ new/src/hotspot/share/gc/z/zNUMA.inline.hpp 2020-01-15 13:47:35.842412098 +0100 @@ -0,0 +1,33 @@ +/* + * Copyright (c) 2019, 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 SHARE_GC_Z_ZNUMA_INLINE_HPP +#define SHARE_GC_Z_ZNUMA_INLINE_HPP + +#include "gc/z/zNUMA.hpp" + +inline bool ZNUMA::is_enabled() { + return _enabled; +} + +#endif // SHARE_GC_Z_ZNUMA_INLINE_HPP --- old/src/hotspot/os/bsd/gc/z/zPhysicalMemoryBacking_bsd.cpp 2020-01-15 13:47:36.572426954 +0100 +++ /dev/null 2020-01-07 09:26:22.747784373 +0100 @@ -1,219 +0,0 @@ -/* - * Copyright (c) 2019, 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. - */ - -#include "precompiled.hpp" -#include "gc/z/zAddress.inline.hpp" -#include "gc/z/zGlobals.hpp" -#include "gc/z/zLargePages.inline.hpp" -#include "gc/z/zPhysicalMemory.inline.hpp" -#include "gc/z/zPhysicalMemoryBacking_bsd.hpp" -#include "runtime/globals.hpp" -#include "runtime/init.hpp" -#include "runtime/os.hpp" -#include "utilities/align.hpp" -#include "utilities/debug.hpp" - -bool ZPhysicalMemoryBacking::is_initialized() const { - return _file.is_initialized(); -} - -void ZPhysicalMemoryBacking::warn_commit_limits(size_t max) const { - // Does nothing -} - -bool ZPhysicalMemoryBacking::supports_uncommit() { - assert(!is_init_completed(), "Invalid state"); - assert(_file.size() >= ZGranuleSize, "Invalid size"); - - // Test if uncommit is supported by uncommitting and then re-committing a granule - return commit(uncommit(ZGranuleSize)) == ZGranuleSize; -} - -size_t ZPhysicalMemoryBacking::commit(size_t size) { - size_t committed = 0; - - // Fill holes in the backing file - while (committed < size) { - size_t allocated = 0; - const size_t remaining = size - committed; - const uintptr_t start = _uncommitted.alloc_from_front_at_most(remaining, &allocated); - if (start == UINTPTR_MAX) { - // No holes to commit - break; - } - - // Try commit hole - const size_t filled = _file.commit(start, allocated); - if (filled > 0) { - // Successful or partialy successful - _committed.free(start, filled); - committed += filled; - } - if (filled < allocated) { - // Failed or partialy failed - _uncommitted.free(start + filled, allocated - filled); - return committed; - } - } - - // Expand backing file - if (committed < size) { - const size_t remaining = size - committed; - const uintptr_t start = _file.size(); - const size_t expanded = _file.commit(start, remaining); - if (expanded > 0) { - // Successful or partialy successful - _committed.free(start, expanded); - committed += expanded; - } - } - - return committed; -} - -size_t ZPhysicalMemoryBacking::uncommit(size_t size) { - size_t uncommitted = 0; - - // Punch holes in backing file - while (uncommitted < size) { - size_t allocated = 0; - const size_t remaining = size - uncommitted; - const uintptr_t start = _committed.alloc_from_back_at_most(remaining, &allocated); - assert(start != UINTPTR_MAX, "Allocation should never fail"); - - // Try punch hole - const size_t punched = _file.uncommit(start, allocated); - if (punched > 0) { - // Successful or partialy successful - _uncommitted.free(start, punched); - uncommitted += punched; - } - if (punched < allocated) { - // Failed or partialy failed - _committed.free(start + punched, allocated - punched); - return uncommitted; - } - } - - return uncommitted; -} - -ZPhysicalMemory ZPhysicalMemoryBacking::alloc(size_t size) { - assert(is_aligned(size, ZGranuleSize), "Invalid size"); - - ZPhysicalMemory pmem; - - // Allocate segments - for (size_t allocated = 0; allocated < size; allocated += ZGranuleSize) { - const uintptr_t start = _committed.alloc_from_front(ZGranuleSize); - assert(start != UINTPTR_MAX, "Allocation should never fail"); - pmem.add_segment(ZPhysicalMemorySegment(start, ZGranuleSize)); - } - - return pmem; -} - -void ZPhysicalMemoryBacking::free(const ZPhysicalMemory& pmem) { - const size_t nsegments = pmem.nsegments(); - - // Free segments - for (size_t i = 0; i < nsegments; i++) { - const ZPhysicalMemorySegment& segment = pmem.segment(i); - _committed.free(segment.start(), segment.size()); - } -} - -void ZPhysicalMemoryBacking::pretouch_view(uintptr_t addr, size_t size) const { - const size_t page_size = ZLargePages::is_explicit() ? ZGranuleSize : os::vm_page_size(); - os::pretouch_memory((void*)addr, (void*)(addr + size), page_size); -} - -void ZPhysicalMemoryBacking::map_view(const ZPhysicalMemory& pmem, uintptr_t addr) const { - const size_t nsegments = pmem.nsegments(); - size_t size = 0; - - // Map segments - for (size_t i = 0; i < nsegments; i++) { - const ZPhysicalMemorySegment& segment = pmem.segment(i); - const uintptr_t segment_addr = addr + size; - _file.map(segment_addr, segment.size(), segment.start()); - size += segment.size(); - } -} - -void ZPhysicalMemoryBacking::unmap_view(const ZPhysicalMemory& pmem, uintptr_t addr) const { - _file.unmap(addr, pmem.size()); -} - -uintptr_t ZPhysicalMemoryBacking::nmt_address(uintptr_t offset) const { - // From an NMT point of view we treat the first heap view (marked0) as committed - return ZAddress::marked0(offset); -} - -void ZPhysicalMemoryBacking::pretouch(uintptr_t offset, size_t size) const { - if (ZVerifyViews) { - // Pre-touch good view - pretouch_view(ZAddress::good(offset), size); - } else { - // Pre-touch all views - pretouch_view(ZAddress::marked0(offset), size); - pretouch_view(ZAddress::marked1(offset), size); - pretouch_view(ZAddress::remapped(offset), size); - } -} - -void ZPhysicalMemoryBacking::map(const ZPhysicalMemory& pmem, uintptr_t offset) const { - if (ZVerifyViews) { - // Map good view - map_view(pmem, ZAddress::good(offset)); - } else { - // Map all views - map_view(pmem, ZAddress::marked0(offset)); - map_view(pmem, ZAddress::marked1(offset)); - map_view(pmem, ZAddress::remapped(offset)); - } -} - -void ZPhysicalMemoryBacking::unmap(const ZPhysicalMemory& pmem, uintptr_t offset) const { - if (ZVerifyViews) { - // Unmap good view - unmap_view(pmem, ZAddress::good(offset)); - } else { - // Unmap all views - unmap_view(pmem, ZAddress::marked0(offset)); - unmap_view(pmem, ZAddress::marked1(offset)); - unmap_view(pmem, ZAddress::remapped(offset)); - } -} - -void ZPhysicalMemoryBacking::debug_map(const ZPhysicalMemory& pmem, uintptr_t offset) const { - // Map good view - assert(ZVerifyViews, "Should be enabled"); - map_view(pmem, ZAddress::good(offset)); -} - -void ZPhysicalMemoryBacking::debug_unmap(const ZPhysicalMemory& pmem, uintptr_t offset) const { - // Unmap good view - assert(ZVerifyViews, "Should be enabled"); - unmap_view(pmem, ZAddress::good(offset)); -} --- old/src/hotspot/os/bsd/gc/z/zPhysicalMemoryBacking_bsd.hpp 2020-01-15 13:47:36.924434117 +0100 +++ /dev/null 2020-01-07 09:26:22.747784373 +0100 @@ -1,65 +0,0 @@ -/* - * Copyright (c) 2019, 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_BSD_GC_Z_ZPHYSICALMEMORYBACKING_BSD_HPP -#define OS_BSD_GC_Z_ZPHYSICALMEMORYBACKING_BSD_HPP - -#include "gc/z/zBackingFile_bsd.hpp" -#include "gc/z/zMemory.hpp" - -class ZPhysicalMemory; - -class ZPhysicalMemoryBacking { -private: - ZBackingFile _file; - ZMemoryManager _committed; - ZMemoryManager _uncommitted; - - void pretouch_view(uintptr_t addr, size_t size) const; - void map_view(const ZPhysicalMemory& pmem, uintptr_t addr) const; - void unmap_view(const ZPhysicalMemory& pmem, uintptr_t addr) const; - -public: - bool is_initialized() const; - - void warn_commit_limits(size_t max) const; - bool supports_uncommit(); - - size_t commit(size_t size); - size_t uncommit(size_t size); - - ZPhysicalMemory alloc(size_t size); - void free(const ZPhysicalMemory& pmem); - - uintptr_t nmt_address(uintptr_t offset) const; - - void pretouch(uintptr_t offset, size_t size) const; - - void map(const ZPhysicalMemory& pmem, uintptr_t offset) const; - void unmap(const ZPhysicalMemory& pmem, uintptr_t offset) const; - - void debug_map(const ZPhysicalMemory& pmem, uintptr_t offset) const; - void debug_unmap(const ZPhysicalMemory& pmem, uintptr_t offset) const; -}; - -#endif // OS_BSD_GC_Z_ZPHYSICALMEMORYBACKING_BSD_HPP --- old/src/hotspot/os/linux/gc/z/zPhysicalMemoryBacking_linux.cpp 2020-01-15 13:47:37.274441239 +0100 +++ /dev/null 2020-01-07 09:26:22.747784373 +0100 @@ -1,340 +0,0 @@ -/* - * Copyright (c) 2015, 2019, 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. - */ - -#include "precompiled.hpp" -#include "gc/z/zAddress.inline.hpp" -#include "gc/z/zErrno.hpp" -#include "gc/z/zGlobals.hpp" -#include "gc/z/zLargePages.inline.hpp" -#include "gc/z/zMemory.hpp" -#include "gc/z/zNUMA.hpp" -#include "gc/z/zPhysicalMemory.inline.hpp" -#include "gc/z/zPhysicalMemoryBacking_linux.hpp" -#include "logging/log.hpp" -#include "runtime/globals.hpp" -#include "runtime/init.hpp" -#include "runtime/os.hpp" -#include "utilities/align.hpp" -#include "utilities/debug.hpp" - -#include -#include -#include - -// -// Support for building on older Linux systems -// - -// madvise(2) flags -#ifndef MADV_HUGEPAGE -#define MADV_HUGEPAGE 14 -#endif - -// Proc file entry for max map mount -#define ZFILENAME_PROC_MAX_MAP_COUNT "/proc/sys/vm/max_map_count" - -bool ZPhysicalMemoryBacking::is_initialized() const { - return _file.is_initialized(); -} - -void ZPhysicalMemoryBacking::warn_available_space(size_t max) const { - // Note that the available space on a tmpfs or a hugetlbfs filesystem - // will be zero if no size limit was specified when it was mounted. - const size_t available = _file.available(); - if (available == 0) { - // No size limit set, skip check - log_info(gc, init)("Available space on backing filesystem: N/A"); - return; - } - - log_info(gc, init)("Available space on backing filesystem: " SIZE_FORMAT "M", available / M); - - // Warn if the filesystem doesn't currently have enough space available to hold - // the max heap size. The max heap size will be capped if we later hit this limit - // when trying to expand the heap. - if (available < max) { - log_warning(gc)("***** WARNING! INCORRECT SYSTEM CONFIGURATION DETECTED! *****"); - log_warning(gc)("Not enough space available on the backing filesystem to hold the current max Java heap"); - log_warning(gc)("size (" SIZE_FORMAT "M). Please adjust the size of the backing filesystem accordingly " - "(available", max / M); - log_warning(gc)("space is currently " SIZE_FORMAT "M). Continuing execution with the current filesystem " - "size could", available / M); - log_warning(gc)("lead to a premature OutOfMemoryError being thrown, due to failure to map memory."); - } -} - -void ZPhysicalMemoryBacking::warn_max_map_count(size_t max) const { - const char* const filename = ZFILENAME_PROC_MAX_MAP_COUNT; - FILE* const file = fopen(filename, "r"); - if (file == NULL) { - // Failed to open file, skip check - log_debug(gc, init)("Failed to open %s", filename); - return; - } - - size_t actual_max_map_count = 0; - const int result = fscanf(file, SIZE_FORMAT, &actual_max_map_count); - fclose(file); - if (result != 1) { - // Failed to read file, skip check - log_debug(gc, init)("Failed to read %s", filename); - return; - } - - // The required max map count is impossible to calculate exactly since subsystems - // other than ZGC are also creating memory mappings, and we have no control over that. - // However, ZGC tends to create the most mappings and dominate the total count. - // In the worst cases, ZGC will map each granule three times, i.e. once per heap view. - // We speculate that we need another 20% to allow for non-ZGC subsystems to map memory. - const size_t required_max_map_count = (max / ZGranuleSize) * 3 * 1.2; - if (actual_max_map_count < required_max_map_count) { - log_warning(gc)("***** WARNING! INCORRECT SYSTEM CONFIGURATION DETECTED! *****"); - log_warning(gc)("The system limit on number of memory mappings per process might be too low for the given"); - log_warning(gc)("max Java heap size (" SIZE_FORMAT "M). Please adjust %s to allow for at", - max / M, filename); - log_warning(gc)("least " SIZE_FORMAT " mappings (current limit is " SIZE_FORMAT "). Continuing execution " - "with the current", required_max_map_count, actual_max_map_count); - log_warning(gc)("limit could lead to a fatal error, due to failure to map memory."); - } -} - -void ZPhysicalMemoryBacking::warn_commit_limits(size_t max) const { - // Warn if available space is too low - warn_available_space(max); - - // Warn if max map count is too low - warn_max_map_count(max); -} - -bool ZPhysicalMemoryBacking::supports_uncommit() { - assert(!is_init_completed(), "Invalid state"); - assert(_file.size() >= ZGranuleSize, "Invalid size"); - - // Test if uncommit is supported by uncommitting and then re-committing a granule - return commit(uncommit(ZGranuleSize)) == ZGranuleSize; -} - -size_t ZPhysicalMemoryBacking::commit(size_t size) { - size_t committed = 0; - - // Fill holes in the backing file - while (committed < size) { - size_t allocated = 0; - const size_t remaining = size - committed; - const uintptr_t start = _uncommitted.alloc_from_front_at_most(remaining, &allocated); - if (start == UINTPTR_MAX) { - // No holes to commit - break; - } - - // Try commit hole - const size_t filled = _file.commit(start, allocated); - if (filled > 0) { - // Successful or partialy successful - _committed.free(start, filled); - committed += filled; - } - if (filled < allocated) { - // Failed or partialy failed - _uncommitted.free(start + filled, allocated - filled); - return committed; - } - } - - // Expand backing file - if (committed < size) { - const size_t remaining = size - committed; - const uintptr_t start = _file.size(); - const size_t expanded = _file.commit(start, remaining); - if (expanded > 0) { - // Successful or partialy successful - _committed.free(start, expanded); - committed += expanded; - } - } - - return committed; -} - -size_t ZPhysicalMemoryBacking::uncommit(size_t size) { - size_t uncommitted = 0; - - // Punch holes in backing file - while (uncommitted < size) { - size_t allocated = 0; - const size_t remaining = size - uncommitted; - const uintptr_t start = _committed.alloc_from_back_at_most(remaining, &allocated); - assert(start != UINTPTR_MAX, "Allocation should never fail"); - - // Try punch hole - const size_t punched = _file.uncommit(start, allocated); - if (punched > 0) { - // Successful or partialy successful - _uncommitted.free(start, punched); - uncommitted += punched; - } - if (punched < allocated) { - // Failed or partialy failed - _committed.free(start + punched, allocated - punched); - return uncommitted; - } - } - - return uncommitted; -} - -ZPhysicalMemory ZPhysicalMemoryBacking::alloc(size_t size) { - assert(is_aligned(size, ZGranuleSize), "Invalid size"); - - ZPhysicalMemory pmem; - - // Allocate segments - for (size_t allocated = 0; allocated < size; allocated += ZGranuleSize) { - const uintptr_t start = _committed.alloc_from_front(ZGranuleSize); - assert(start != UINTPTR_MAX, "Allocation should never fail"); - pmem.add_segment(ZPhysicalMemorySegment(start, ZGranuleSize)); - } - - return pmem; -} - -void ZPhysicalMemoryBacking::free(const ZPhysicalMemory& pmem) { - const size_t nsegments = pmem.nsegments(); - - // Free segments - for (size_t i = 0; i < nsegments; i++) { - const ZPhysicalMemorySegment& segment = pmem.segment(i); - _committed.free(segment.start(), segment.size()); - } -} - -void ZPhysicalMemoryBacking::map_failed(ZErrno err) const { - if (err == ENOMEM) { - fatal("Failed to map memory. Please check the system limit on number of " - "memory mappings allowed per process (see %s)", ZFILENAME_PROC_MAX_MAP_COUNT); - } else { - fatal("Failed to map memory (%s)", err.to_string()); - } -} - -void ZPhysicalMemoryBacking::advise_view(uintptr_t addr, size_t size, int advice) const { - if (madvise((void*)addr, size, advice) == -1) { - ZErrno err; - log_error(gc)("Failed to advise on memory (advice %d, %s)", advice, err.to_string()); - } -} - -void ZPhysicalMemoryBacking::pretouch_view(uintptr_t addr, size_t size) const { - const size_t page_size = ZLargePages::is_explicit() ? os::large_page_size() : os::vm_page_size(); - os::pretouch_memory((void*)addr, (void*)(addr + size), page_size); -} - -void ZPhysicalMemoryBacking::map_view(const ZPhysicalMemory& pmem, uintptr_t addr) const { - const size_t nsegments = pmem.nsegments(); - size_t size = 0; - - // Map segments - for (size_t i = 0; i < nsegments; i++) { - const ZPhysicalMemorySegment& segment = pmem.segment(i); - const uintptr_t segment_addr = addr + size; - const void* const res = mmap((void*)segment_addr, segment.size(), PROT_READ|PROT_WRITE, MAP_FIXED|MAP_SHARED, _file.fd(), segment.start()); - if (res == MAP_FAILED) { - ZErrno err; - map_failed(err); - } - - size += segment.size(); - } - - // Advise on use of transparent huge pages before touching it - if (ZLargePages::is_transparent()) { - advise_view(addr, size, MADV_HUGEPAGE); - } - - // NUMA interleave memory before touching it - ZNUMA::memory_interleave(addr, size); -} - -void ZPhysicalMemoryBacking::unmap_view(const ZPhysicalMemory& pmem, uintptr_t addr) const { - // Note that we must keep the address space reservation intact and just detach - // the backing memory. For this reason we map a new anonymous, non-accessible - // and non-reserved page over the mapping instead of actually unmapping. - const void* const res = mmap((void*)addr, pmem.size(), PROT_NONE, MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE|MAP_NORESERVE, -1, 0); - if (res == MAP_FAILED) { - ZErrno err; - map_failed(err); - } -} - -uintptr_t ZPhysicalMemoryBacking::nmt_address(uintptr_t offset) const { - // From an NMT point of view we treat the first heap view (marked0) as committed - return ZAddress::marked0(offset); -} - -void ZPhysicalMemoryBacking::pretouch(uintptr_t offset, size_t size) const { - if (ZVerifyViews) { - // Pre-touch good view - pretouch_view(ZAddress::good(offset), size); - } else { - // Pre-touch all views - pretouch_view(ZAddress::marked0(offset), size); - pretouch_view(ZAddress::marked1(offset), size); - pretouch_view(ZAddress::remapped(offset), size); - } -} - -void ZPhysicalMemoryBacking::map(const ZPhysicalMemory& pmem, uintptr_t offset) const { - if (ZVerifyViews) { - // Map good view - map_view(pmem, ZAddress::good(offset)); - } else { - // Map all views - map_view(pmem, ZAddress::marked0(offset)); - map_view(pmem, ZAddress::marked1(offset)); - map_view(pmem, ZAddress::remapped(offset)); - } -} - -void ZPhysicalMemoryBacking::unmap(const ZPhysicalMemory& pmem, uintptr_t offset) const { - if (ZVerifyViews) { - // Unmap good view - unmap_view(pmem, ZAddress::good(offset)); - } else { - // Unmap all views - unmap_view(pmem, ZAddress::marked0(offset)); - unmap_view(pmem, ZAddress::marked1(offset)); - unmap_view(pmem, ZAddress::remapped(offset)); - } -} - -void ZPhysicalMemoryBacking::debug_map(const ZPhysicalMemory& pmem, uintptr_t offset) const { - // Map good view - assert(ZVerifyViews, "Should be enabled"); - map_view(pmem, ZAddress::good(offset)); -} - -void ZPhysicalMemoryBacking::debug_unmap(const ZPhysicalMemory& pmem, uintptr_t offset) const { - // Unmap good view - assert(ZVerifyViews, "Should be enabled"); - unmap_view(pmem, ZAddress::good(offset)); -} --- old/src/hotspot/os/linux/gc/z/zPhysicalMemoryBacking_linux.hpp 2020-01-15 13:47:37.619448260 +0100 +++ /dev/null 2020-01-07 09:26:22.747784373 +0100 @@ -1,72 +0,0 @@ -/* - * Copyright (c) 2015, 2019, 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_GC_Z_ZPHYSICALMEMORYBACKING_LINUX_HPP -#define OS_LINUX_GC_Z_ZPHYSICALMEMORYBACKING_LINUX_HPP - -#include "gc/z/zBackingFile_linux.hpp" -#include "gc/z/zMemory.hpp" - -class ZErrno; -class ZPhysicalMemory; - -class ZPhysicalMemoryBacking { -private: - ZBackingFile _file; - ZMemoryManager _committed; - ZMemoryManager _uncommitted; - - void warn_available_space(size_t max) const; - void warn_max_map_count(size_t max) const; - - void map_failed(ZErrno err) const; - - void advise_view(uintptr_t addr, size_t size, int advice) const; - void pretouch_view(uintptr_t addr, size_t size) const; - void map_view(const ZPhysicalMemory& pmem, uintptr_t addr) const; - void unmap_view(const ZPhysicalMemory& pmem, uintptr_t addr) const; - -public: - bool is_initialized() const; - - void warn_commit_limits(size_t max) const; - bool supports_uncommit(); - - size_t commit(size_t size); - size_t uncommit(size_t size); - - ZPhysicalMemory alloc(size_t size); - void free(const ZPhysicalMemory& pmem); - - uintptr_t nmt_address(uintptr_t offset) const; - - void pretouch(uintptr_t offset, size_t size) const; - - void map(const ZPhysicalMemory& pmem, uintptr_t offset) const; - void unmap(const ZPhysicalMemory& pmem, uintptr_t offset) const; - - void debug_map(const ZPhysicalMemory& pmem, uintptr_t offset) const; - void debug_unmap(const ZPhysicalMemory& pmem, uintptr_t offset) const; -}; - -#endif // OS_LINUX_GC_Z_ZPHYSICALMEMORYBACKING_LINUX_HPP --- old/src/hotspot/os/windows/gc/z/zPhysicalMemoryBacking_windows.cpp 2020-01-15 13:47:37.961455220 +0100 +++ /dev/null 2020-01-07 09:26:22.747784373 +0100 @@ -1,219 +0,0 @@ -/* - * Copyright (c) 2019, 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. - */ - -#include "precompiled.hpp" -#include "gc/z/zAddress.inline.hpp" -#include "gc/z/zGlobals.hpp" -#include "gc/z/zLargePages.inline.hpp" -#include "gc/z/zMapper_windows.hpp" -#include "gc/z/zPhysicalMemory.inline.hpp" -#include "gc/z/zPhysicalMemoryBacking_windows.hpp" -#include "runtime/globals.hpp" -#include "runtime/init.hpp" -#include "runtime/os.hpp" -#include "utilities/align.hpp" -#include "utilities/debug.hpp" - -bool ZPhysicalMemoryBacking::is_initialized() const { - return true; -} - -void ZPhysicalMemoryBacking::warn_commit_limits(size_t max) const { - // Does nothing -} - -bool ZPhysicalMemoryBacking::supports_uncommit() { - assert(!is_init_completed(), "Invalid state"); - assert(_file.size() >= ZGranuleSize, "Invalid size"); - - // Test if uncommit is supported by uncommitting and then re-committing a granule - return commit(uncommit(ZGranuleSize)) == ZGranuleSize; -} - -size_t ZPhysicalMemoryBacking::commit(size_t size) { - size_t committed = 0; - - // Fill holes in the backing file - while (committed < size) { - size_t allocated = 0; - const size_t remaining = size - committed; - const uintptr_t start = _uncommitted.alloc_from_front_at_most(remaining, &allocated); - if (start == UINTPTR_MAX) { - // No holes to commit - break; - } - - // Try commit hole - const size_t filled = _file.commit(start, allocated); - if (filled > 0) { - // Successful or partialy successful - _committed.free(start, filled); - committed += filled; - } - if (filled < allocated) { - // Failed or partialy failed - _uncommitted.free(start + filled, allocated - filled); - return committed; - } - } - - // Expand backing file - if (committed < size) { - const size_t remaining = size - committed; - const uintptr_t start = _file.size(); - const size_t expanded = _file.commit(start, remaining); - if (expanded > 0) { - // Successful or partialy successful - _committed.free(start, expanded); - committed += expanded; - } - } - - return committed; -} - -size_t ZPhysicalMemoryBacking::uncommit(size_t size) { - size_t uncommitted = 0; - - // Punch holes in backing file - while (uncommitted < size) { - size_t allocated = 0; - const size_t remaining = size - uncommitted; - const uintptr_t start = _committed.alloc_from_back_at_most(remaining, &allocated); - assert(start != UINTPTR_MAX, "Allocation should never fail"); - - // Try punch hole - const size_t punched = _file.uncommit(start, allocated); - if (punched > 0) { - // Successful or partialy successful - _uncommitted.free(start, punched); - uncommitted += punched; - } - if (punched < allocated) { - // Failed or partialy failed - _committed.free(start + punched, allocated - punched); - return uncommitted; - } - } - - return uncommitted; -} - -ZPhysicalMemory ZPhysicalMemoryBacking::alloc(size_t size) { - assert(is_aligned(size, ZGranuleSize), "Invalid size"); - - ZPhysicalMemory pmem; - - // Allocate segments - for (size_t allocated = 0; allocated < size; allocated += ZGranuleSize) { - const uintptr_t start = _committed.alloc_from_front(ZGranuleSize); - assert(start != UINTPTR_MAX, "Allocation should never fail"); - pmem.add_segment(ZPhysicalMemorySegment(start, ZGranuleSize)); - } - - return pmem; -} - -void ZPhysicalMemoryBacking::free(const ZPhysicalMemory& pmem) { - const size_t nsegments = pmem.nsegments(); - - // Free segments - for (size_t i = 0; i < nsegments; i++) { - const ZPhysicalMemorySegment& segment = pmem.segment(i); - _committed.free(segment.start(), segment.size()); - } -} - -void ZPhysicalMemoryBacking::pretouch_view(uintptr_t addr, size_t size) const { - const size_t page_size = ZLargePages::is_explicit() ? os::large_page_size() : os::vm_page_size(); - os::pretouch_memory((void*)addr, (void*)(addr + size), page_size); -} - -void ZPhysicalMemoryBacking::map_view(const ZPhysicalMemory& pmem, uintptr_t addr) const { - const size_t nsegments = pmem.nsegments(); - size_t size = 0; - - // Map segments - for (size_t i = 0; i < nsegments; i++) { - const ZPhysicalMemorySegment& segment = pmem.segment(i); - _file.map(addr + size, segment.size(), segment.start()); - size += segment.size(); - } -} - -void ZPhysicalMemoryBacking::unmap_view(const ZPhysicalMemory& pmem, uintptr_t addr) const { - _file.unmap(addr, pmem.size()); -} - -uintptr_t ZPhysicalMemoryBacking::nmt_address(uintptr_t offset) const { - // From an NMT point of view we treat the first heap view (marked0) as committed - return ZAddress::marked0(offset); -} - -void ZPhysicalMemoryBacking::pretouch(uintptr_t offset, size_t size) const { - if (ZVerifyViews) { - // Pre-touch good view - pretouch_view(ZAddress::good(offset), size); - } else { - // Pre-touch all views - pretouch_view(ZAddress::marked0(offset), size); - pretouch_view(ZAddress::marked1(offset), size); - pretouch_view(ZAddress::remapped(offset), size); - } -} - -void ZPhysicalMemoryBacking::map(const ZPhysicalMemory& pmem, uintptr_t offset) const { - if (ZVerifyViews) { - // Map good view - map_view(pmem, ZAddress::good(offset)); - } else { - // Map all views - map_view(pmem, ZAddress::marked0(offset)); - map_view(pmem, ZAddress::marked1(offset)); - map_view(pmem, ZAddress::remapped(offset)); - } -} - -void ZPhysicalMemoryBacking::unmap(const ZPhysicalMemory& pmem, uintptr_t offset) const { - if (ZVerifyViews) { - // Unmap good view - unmap_view(pmem, ZAddress::good(offset)); - } else { - // Unmap all views - unmap_view(pmem, ZAddress::marked0(offset)); - unmap_view(pmem, ZAddress::marked1(offset)); - unmap_view(pmem, ZAddress::remapped(offset)); - } -} - -void ZPhysicalMemoryBacking::debug_map(const ZPhysicalMemory& pmem, uintptr_t offset) const { - // Map good view - assert(ZVerifyViews, "Should be enabled"); - map_view(pmem, ZAddress::good(offset)); -} - -void ZPhysicalMemoryBacking::debug_unmap(const ZPhysicalMemory& pmem, uintptr_t offset) const { - // Unmap good view - assert(ZVerifyViews, "Should be enabled"); - unmap_view(pmem, ZAddress::good(offset)); -} --- old/src/hotspot/os/windows/gc/z/zPhysicalMemoryBacking_windows.hpp 2020-01-15 13:47:38.306462240 +0100 +++ /dev/null 2020-01-07 09:26:22.747784373 +0100 @@ -1,65 +0,0 @@ -/* - * Copyright (c) 2019, 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_WINDOWS_GC_Z_ZPHYSICALMEMORYBACKING_WINDOWS_HPP -#define OS_WINDOWS_GC_Z_ZPHYSICALMEMORYBACKING_WINDOWS_HPP - -#include "gc/z/zBackingFile_windows.hpp" -#include "gc/z/zMemory.hpp" - -class ZPhysicalMemory; - -class ZPhysicalMemoryBacking { -private: - ZBackingFile _file; - ZMemoryManager _committed; - ZMemoryManager _uncommitted; - - void pretouch_view(uintptr_t addr, size_t size) const; - void map_view(const ZPhysicalMemory& pmem, uintptr_t addr) const; - void unmap_view(const ZPhysicalMemory& pmem, uintptr_t addr) const; - -public: - bool is_initialized() const; - - void warn_commit_limits(size_t max) const; - bool supports_uncommit(); - - size_t commit(size_t size); - size_t uncommit(size_t size); - - ZPhysicalMemory alloc(size_t size); - void free(const ZPhysicalMemory& pmem); - - uintptr_t nmt_address(uintptr_t offset) const; - - void pretouch(uintptr_t offset, size_t size) const; - - void map(const ZPhysicalMemory& pmem, uintptr_t offset) const; - void unmap(const ZPhysicalMemory& pmem, uintptr_t offset) const; - - void debug_map(const ZPhysicalMemory& pmem, uintptr_t offset) const; - void debug_unmap(const ZPhysicalMemory& pmem, uintptr_t offset) const; -}; - -#endif // OS_WINDOWS_GC_Z_ZPHYSICALMEMORYBACKING_WINDOWS_HPP