-
Notifications
You must be signed in to change notification settings - Fork 28
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
- Loading branch information
Showing
9 changed files
with
749 additions
and
133 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,228 @@ | ||
/* | ||
* Copyright (c) 2005, 2023, Oracle and/or its affiliates. All rights reserved. | ||
* Copyright (c) 2011, 2023, Red Hat Inc. 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 "hugepages.hpp" | ||
|
||
#include "logging/log.hpp" | ||
#include "logging/logStream.hpp" | ||
#include "runtime/os.hpp" | ||
#include "utilities/debug.hpp" | ||
#include "utilities/globalDefinitions.hpp" | ||
#include "utilities/ostream.hpp" | ||
|
||
#include <dirent.h> | ||
|
||
StaticHugePageSupport::StaticHugePageSupport() : | ||
_initialized(false), _pagesizes(), _default_hugepage_size(SIZE_MAX) {} | ||
|
||
os::PageSizes StaticHugePageSupport::pagesizes() const { | ||
assert(_initialized, "Not initialized"); | ||
return _pagesizes; | ||
} | ||
|
||
size_t StaticHugePageSupport::default_hugepage_size() const { | ||
assert(_initialized, "Not initialized"); | ||
return _default_hugepage_size; | ||
} | ||
|
||
// Scan /proc/meminfo and return value of Hugepagesize | ||
static size_t scan_default_hugepagesize() { | ||
size_t pagesize = 0; | ||
|
||
// large_page_size on Linux is used to round up heap size. x86 uses either | ||
// 2M or 4M page, depending on whether PAE (Physical Address Extensions) | ||
// mode is enabled. AMD64/EM64T uses 2M page in 64bit mode. IA64 can use | ||
// page as large as 1G. | ||
// | ||
// Here we try to figure out page size by parsing /proc/meminfo and looking | ||
// for a line with the following format: | ||
// Hugepagesize: 2048 kB | ||
// | ||
// If we can't determine the value (e.g. /proc is not mounted, or the text | ||
// format has been changed), we'll set largest page size to 0 | ||
|
||
FILE *fp = os::fopen("/proc/meminfo", "r"); | ||
if (fp) { | ||
while (!feof(fp)) { | ||
int x = 0; | ||
char buf[16]; | ||
if (fscanf(fp, "Hugepagesize: %d", &x) == 1) { | ||
if (x && fgets(buf, sizeof(buf), fp) && strcmp(buf, " kB\n") == 0) { | ||
pagesize = x * K; | ||
break; | ||
} | ||
} else { | ||
// skip to next line | ||
for (;;) { | ||
int ch = fgetc(fp); | ||
if (ch == EOF || ch == (int)'\n') break; | ||
} | ||
} | ||
} | ||
fclose(fp); | ||
} | ||
|
||
return pagesize; | ||
} | ||
|
||
// Given a file that contains a single (integral) number, return that number in (*out) and true; | ||
// in case of an error, return false. | ||
static bool read_number_file(const char* file, size_t* out) { | ||
FILE* f = ::fopen(file, "r"); | ||
bool rc = false; | ||
if (f != nullptr) { | ||
uint64_t i = 0; | ||
if (::fscanf(f, SIZE_FORMAT, out) == 1) { | ||
rc = true; | ||
} | ||
::fclose(f); | ||
} | ||
return rc; | ||
} | ||
|
||
static const char* const sys_hugepages = "/sys/kernel/mm/hugepages"; | ||
|
||
// Scan all directories in /sys/kernel/mm/hugepages/hugepages-xxxx | ||
// to discover the available page sizes | ||
static os::PageSizes scan_hugepages() { | ||
|
||
os::PageSizes pagesizes; | ||
|
||
DIR *dir = opendir(sys_hugepages); | ||
|
||
struct dirent *entry; | ||
size_t pagesize; | ||
while ((entry = readdir(dir)) != nullptr) { | ||
if (entry->d_type == DT_DIR && | ||
sscanf(entry->d_name, "hugepages-%zukB", &pagesize) == 1) { | ||
// The kernel is using kB, hotspot uses bytes | ||
// Add each found Large Page Size to page_sizes | ||
pagesize *= K; | ||
pagesizes.add(pagesize); | ||
} | ||
} | ||
closedir(dir); | ||
|
||
return pagesizes; | ||
} | ||
|
||
void StaticHugePageSupport::print_on(outputStream* os) { | ||
if (_initialized) { | ||
os->print_cr("Static hugepage support:"); | ||
for (size_t s = _pagesizes.smallest(); s != 0; s = _pagesizes.next_larger(s)) { | ||
os->print_cr(" hugepage size: " EXACTFMT, EXACTFMTARGS(s)); | ||
} | ||
os->print_cr(" default hugepage size: " EXACTFMT, EXACTFMTARGS(_default_hugepage_size)); | ||
} else { | ||
os->print_cr(" unknown."); | ||
} | ||
} | ||
|
||
void StaticHugePageSupport::scan_os() { | ||
_pagesizes = scan_hugepages(); | ||
_default_hugepage_size = scan_default_hugepagesize(); | ||
assert(_pagesizes.contains(_default_hugepage_size), | ||
"Unexpected configuration: default pagesize (" SIZE_FORMAT ") " | ||
"has no associated directory in /sys/kernel/mm/hugepages..", _default_hugepage_size); | ||
_initialized = true; | ||
LogTarget(Info, pagesize) lt; | ||
if (lt.is_enabled()) { | ||
LogStream ls(lt); | ||
print_on(&ls); | ||
} | ||
} | ||
|
||
THPSupport::THPSupport() : | ||
_initialized(false), _mode(THPMode::never), _pagesize(SIZE_MAX) {} | ||
|
||
|
||
THPMode THPSupport::mode() const { | ||
assert(_initialized, "Not initialized"); | ||
return _mode; | ||
} | ||
|
||
size_t THPSupport::pagesize() const { | ||
assert(_initialized, "Not initialized"); | ||
return _pagesize; | ||
} | ||
|
||
void THPSupport::scan_os() { | ||
// Scan /sys/kernel/mm/transparent_hugepage/enabled | ||
// see mm/huge_memory.c | ||
_mode = THPMode::never; | ||
const char* filename = "/sys/kernel/mm/transparent_hugepage/enabled"; | ||
FILE* f = ::fopen(filename, "r"); | ||
if (f != nullptr) { | ||
char buf[64]; | ||
char* s = fgets(buf, sizeof(buf), f); | ||
assert(s == buf, "Should have worked"); | ||
if (::strstr(buf, "[madvise]") != nullptr) { | ||
_mode = THPMode::madvise; | ||
} else if (::strstr(buf, "[always]") != nullptr) { | ||
_mode = THPMode::always; | ||
} else { | ||
assert(::strstr(buf, "[never]") != nullptr, "Weird content of %s: %s", filename, buf); | ||
} | ||
fclose(f); | ||
} | ||
|
||
// Scan large page size for THP from hpage_pmd_size | ||
_pagesize = 0; | ||
if (read_number_file("/sys/kernel/mm/transparent_hugepage/hpage_pmd_size", &_pagesize)) { | ||
assert(_pagesize > 0, "Expected"); | ||
} | ||
_initialized = true; | ||
|
||
LogTarget(Info, pagesize) lt; | ||
if (lt.is_enabled()) { | ||
LogStream ls(lt); | ||
print_on(&ls); | ||
} | ||
} | ||
|
||
void THPSupport::print_on(outputStream* os) { | ||
if (_initialized) { | ||
os->print_cr("Transparent hugepage (THP) support:"); | ||
os->print_cr(" THP mode: %s", | ||
(_mode == THPMode::always ? "always" : (_mode == THPMode::never ? "never" : "madvise"))); | ||
os->print_cr(" THP pagesize: " EXACTFMT, EXACTFMTARGS(_pagesize)); | ||
} else { | ||
os->print_cr(" unknown."); | ||
} | ||
} | ||
|
||
StaticHugePageSupport HugePages::_static_hugepage_support; | ||
THPSupport HugePages::_thp_support; | ||
|
||
void HugePages::initialize() { | ||
_static_hugepage_support.scan_os(); | ||
_thp_support.scan_os(); | ||
} | ||
|
||
void HugePages::print_on(outputStream* os) { | ||
_static_hugepage_support.print_on(os); | ||
_thp_support.print_on(os); | ||
} |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,110 @@ | ||
/* | ||
* Copyright (c) 2005, 2023, Oracle and/or its affiliates. All rights reserved. | ||
* Copyright (c) 2011, 2023, Red Hat Inc. 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_HUGEPAGES_HPP | ||
#define OS_LINUX_HUGEPAGES_HPP | ||
|
||
#include "memory/allStatic.hpp" | ||
#include "runtime/os.hpp" // for os::PageSizes | ||
#include "utilities/globalDefinitions.hpp" | ||
|
||
class outputStream; | ||
|
||
// Header contains the interface that reads OS information about | ||
// available hugepage support: | ||
// - class StaticHugePageSupport - about static (non-THP) hugepages | ||
// - class THPSupport - about transparent huge pages | ||
// and: | ||
// - class HugePages - a static umbrella wrapper | ||
|
||
// Information about static (non-thp) hugepages | ||
class StaticHugePageSupport { | ||
bool _initialized; | ||
|
||
// All supported hugepage sizes (sizes for which entries exist | ||
// in /sys/kernel/mm/hugepages/hugepage-xxx) | ||
os::PageSizes _pagesizes; | ||
|
||
// Contains the default hugepage. The "default hugepage size" is the one that | ||
// - is marked in /proc/meminfo as "Hugepagesize" | ||
// - is the size one gets when using mmap(MAP_HUGETLB) when omitting size specifiers like MAP_HUGE_SHIFT) | ||
size_t _default_hugepage_size; | ||
|
||
public: | ||
StaticHugePageSupport(); | ||
|
||
void scan_os(); | ||
|
||
os::PageSizes pagesizes() const; | ||
size_t default_hugepage_size() const; | ||
void print_on(outputStream* os); | ||
}; | ||
|
||
enum class THPMode { always, never, madvise }; | ||
|
||
// 2) for transparent hugepages | ||
class THPSupport { | ||
bool _initialized; | ||
|
||
// See /sys/kernel/mm/transparent_hugepages/enabled | ||
THPMode _mode; | ||
|
||
// Contains the THP page size | ||
size_t _pagesize; | ||
|
||
public: | ||
|
||
THPSupport(); | ||
|
||
// Queries the OS, fills in object | ||
void scan_os(); | ||
|
||
THPMode mode() const; | ||
size_t pagesize() const; | ||
void print_on(outputStream* os); | ||
}; | ||
|
||
// Umbrella static interface | ||
class HugePages : public AllStatic { | ||
|
||
static StaticHugePageSupport _static_hugepage_support; | ||
static THPSupport _thp_support; | ||
|
||
public: | ||
|
||
static const StaticHugePageSupport& static_info() { return _static_hugepage_support; } | ||
static const THPSupport& thp_info() { return _thp_support; } | ||
|
||
static size_t default_static_hugepage_size() { return _static_hugepage_support.default_hugepage_size(); } | ||
static bool supports_static_hugepages() { return default_static_hugepage_size() > 0; } | ||
static THPMode thp_mode() { return _thp_support.mode(); } | ||
static bool supports_thp() { return thp_mode() == THPMode::madvise || thp_mode() == THPMode::always; } | ||
static size_t thp_pagesize() { return _thp_support.pagesize(); } | ||
|
||
static void initialize(); | ||
static void print_on(outputStream* os); | ||
}; | ||
|
||
#endif // OS_LINUX_HUGEPAGES_HPP |
Oops, something went wrong.