From 02ea3b0dc43522e72c0d129658f93dceadb09fa6 Mon Sep 17 00:00:00 2001
From: Gabriel Schulhof <gabriel.schulhof@intel.com>
Date: Fri, 13 Dec 2019 11:59:37 -0800
Subject: [PATCH 1/9] src: make --use-largepages a runtime option

Moves the option that instructs Node.js to-remap its static code to
large pages from a configure-time option to a runtime option. This
should make it easy to assess the performance impact of such a change
without having to custom-build.

PR-URL: https://github.com/nodejs/node/pull/30954
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: David Carlier <devnexen@gmail.com>
Reviewed-By: David Carlier <devnexen@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Gireesh Punathil <gpunathi@in.ibm.com>
Reviewed-By: Denys Otrishko <shishugi@gmail.com>
Co-authored-by: David Carlier <devnexen@gmail.com>
---
 configure.py                              | 33 -----------------------
 doc/api/cli.md                            | 17 ++++++++++++
 doc/node.1                                | 10 +++++++
 node.gyp                                  |  5 ++--
 node.gypi                                 |  6 ++---
 src/large_pages/node_large_page.cc        | 19 +++++++------
 src/node.cc                               | 30 ++++++++++++++-------
 src/node_options.cc                       |  9 +++++++
 src/node_options.h                        |  1 +
 test/parallel/test-startup-large-pages.js | 29 ++++++++++++++++++++
 10 files changed, 101 insertions(+), 58 deletions(-)
 create mode 100644 test/parallel/test-startup-large-pages.js

diff --git a/configure.py b/configure.py
index 5c1360615de6b3..e53d7d86843d84 100755
--- a/configure.py
+++ b/configure.py
@@ -424,17 +424,6 @@
     dest='with_etw',
     help='build with ETW (default is true on Windows)')
 
-parser.add_option('--use-largepages',
-    action='store_true',
-    dest='node_use_large_pages',
-    help='build with Large Pages support. This feature is supported only on Linux kernel' +
-         '>= 2.6.38 with Transparent Huge pages enabled and FreeBSD')
-
-parser.add_option('--use-largepages-script-lld',
-    action='store_true',
-    dest='node_use_large_pages_script_lld',
-    help='link against the LLVM ld linker script. Implies -fuse-ld=lld in the linker flags')
-
 intl_optgroup.add_option('--with-intl',
     action='store',
     dest='with_intl',
@@ -1092,28 +1081,6 @@ def configure_node(o):
   else:
     o['variables']['node_use_dtrace'] = 'false'
 
-  if options.node_use_large_pages and not flavor in ('linux', 'freebsd', 'mac'):
-    raise Exception(
-      'Large pages are supported only on Linux, FreeBSD and MacOS Systems.')
-  if options.node_use_large_pages and flavor in ('linux', 'freebsd', 'mac'):
-    if options.shared or options.enable_static:
-      raise Exception(
-        'Large pages are supported only while creating node executable.')
-    if target_arch!="x64":
-      raise Exception(
-        'Large pages are supported only x64 platform.')
-    if flavor == 'mac':
-      info('macOS server with 32GB or more is recommended')
-    if flavor == 'linux':
-      # Example full version string: 2.6.32-696.28.1.el6.x86_64
-      FULL_KERNEL_VERSION=os.uname()[2]
-      KERNEL_VERSION=FULL_KERNEL_VERSION.split('-')[0]
-      if KERNEL_VERSION < "2.6.38" and flavor == 'linux':
-        raise Exception(
-          'Large pages need Linux kernel version >= 2.6.38')
-  o['variables']['node_use_large_pages'] = b(options.node_use_large_pages)
-  o['variables']['node_use_large_pages_script_lld'] = b(options.node_use_large_pages_script_lld)
-
   if options.no_ifaddrs:
     o['defines'] += ['SUNOS_NO_IFADDRS']
 
diff --git a/doc/api/cli.md b/doc/api/cli.md
index 2f3c6a9f7da114..f887a3940ea530 100644
--- a/doc/api/cli.md
+++ b/doc/api/cli.md
@@ -900,6 +900,22 @@ environment variables.
 
 See `SSL_CERT_DIR` and `SSL_CERT_FILE`.
 
+### `--use-largepages=mode`
+<!-- YAML
+added: REPLACEME
+-->
+
+Re-map the Node.js static code to large memory pages at startup. If supported on
+the target system, this will cause the Node.js static code to be moved onto 2
+MiB pages instead of 4 KiB pages.
+
+The following values are valid for `mode`:
+* `off`: No mapping will be attempted. This is the default.
+* `on`: If supported by the OS, mapping will be attempted. Failure to map will
+  be ignored and a message will be printed to standard error.
+* `silent`: If supported by the OS, mapping will be attempted. Failure to map
+  will be ignored and will not be reported.
+
 ### `--v8-options`
 <!-- YAML
 added: v0.1.3
@@ -1157,6 +1173,7 @@ Node.js options that are allowed are:
 * `--track-heap-objects`
 * `--unhandled-rejections`
 * `--use-bundled-ca`
+* `--use-largepages`
 * `--use-openssl-ca`
 * `--v8-pool-size`
 * `--zero-fill-buffers`
diff --git a/doc/node.1 b/doc/node.1
index ad82f466f86d45..aafb7d40273d5a 100644
--- a/doc/node.1
+++ b/doc/node.1
@@ -432,6 +432,16 @@ See
 and
 .Ev SSL_CERT_FILE .
 .
+.It Fl -use-largepages Ns = Ns Ar mode
+Re-map the Node.js static code to large memory pages at startup. If supported on
+the target system, this will cause the Node.js static code to be moved onto 2
+MiB pages instead of 4 KiB pages.
+.Pp
+.Ar mode
+must have one of the following values:
+`off` (the default value, meaning do not map), `on` (map and ignore failure,
+reporting it to stderr), or `silent` (map and silently ignore failure).
+.
 .It Fl -v8-options
 Print V8 command-line options.
 .
diff --git a/node.gyp b/node.gyp
index ee99fbe7c522e9..a0b7f25a75d059 100644
--- a/node.gyp
+++ b/node.gyp
@@ -846,10 +846,9 @@
             }],
           ],
         }],
-        [ 'node_use_large_pages=="true" and OS in "linux freebsd mac"', {
+        [ 'OS in "linux freebsd mac" and '
+          'target_arch=="x64"', {
           'defines': [ 'NODE_ENABLE_LARGE_CODE_PAGES=1' ],
-          # The current implementation of Large Pages is under Linux.
-          # Other implementations are possible but not currently supported.
           'sources': [
             'src/large_pages/node_large_page.cc',
             'src/large_pages/node_large_page.h'
diff --git a/node.gypi b/node.gypi
index ff6c36c4b82ea9..cc4f2216764b16 100644
--- a/node.gypi
+++ b/node.gypi
@@ -319,8 +319,7 @@
     }],
     [ 'OS=="linux" and '
       'target_arch=="x64" and '
-      'node_use_large_pages=="true" and '
-      'node_use_large_pages_script_lld=="false"', {
+      'llvm_version=="0.0"', {
       'ldflags': [
         '-Wl,-T',
         '<!(realpath src/large_pages/ld.implicit.script)',
@@ -328,8 +327,7 @@
     }],
     [ 'OS=="linux" and '
       'target_arch=="x64" and '
-      'node_use_large_pages=="true" and '
-      'node_use_large_pages_script_lld=="true"', {
+      'llvm_version!="0.0"', {
       'ldflags': [
         '-Wl,-T',
         '<!(realpath src/large_pages/ld.implicit.script.lld)',
diff --git a/src/large_pages/node_large_page.cc b/src/large_pages/node_large_page.cc
index f636c9f3142376..252ccba15780d6 100644
--- a/src/large_pages/node_large_page.cc
+++ b/src/large_pages/node_large_page.cc
@@ -62,7 +62,7 @@
 // Map a new area and copy the original code there
 // Use mmap using the start address with MAP_FIXED so we get exactly the
 // same virtual address
-// Use madvise with MADV_HUGE_PAGE to use Anonymous 2M Pages
+// Use madvise with MADV_HUGEPAGE to use Anonymous 2M Pages
 // If successful copy the code there and unmap the original region.
 
 extern char __nodetext;
@@ -295,7 +295,7 @@ static bool IsSuperPagesEnabled() {
 // a. map a new area and copy the original code there
 // b. mmap using the start address with MAP_FIXED so we get exactly
 //    the same virtual address (except on macOS).
-// c. madvise with MADV_HUGE_PAGE
+// c. madvise with MADV_HUGEPAGE
 // d. If successful copy the code there and unmap the original region
 int
 #if !defined(__APPLE__)
@@ -320,9 +320,6 @@ MoveTextRegionToLargePages(const text_region& r) {
     PrintSystemError(errno);
     return -1;
   }
-  OnScopeLeave munmap_on_return([nmem, size]() {
-    if (-1 == munmap(nmem, size)) PrintSystemError(errno);
-  });
 
   memcpy(nmem, r.from, size);
 
@@ -339,13 +336,14 @@ MoveTextRegionToLargePages(const text_region& r) {
     return -1;
   }
 
-  ret = madvise(tmem, size, MADV_HUGEPAGE);
+  ret = madvise(tmem, size, 14 /* MADV_HUGEPAGE */);
   if (ret == -1) {
     PrintSystemError(errno);
     ret = munmap(tmem, size);
     if (ret == -1) {
       PrintSystemError(errno);
     }
+    if (-1 == munmap(nmem, size)) PrintSystemError(errno);
     return -1;
   }
   memcpy(start, nmem, size);
@@ -356,6 +354,7 @@ MoveTextRegionToLargePages(const text_region& r) {
               MAP_ALIGNED_SUPER, -1 , 0);
   if (tmem == MAP_FAILED) {
     PrintSystemError(errno);
+    if (-1 == munmap(nmem, size)) PrintSystemError(errno);
     return -1;
   }
 #elif defined(__APPLE__)
@@ -370,6 +369,7 @@ MoveTextRegionToLargePages(const text_region& r) {
               VM_FLAGS_SUPERPAGE_SIZE_2MB, 0);
   if (tmem == MAP_FAILED) {
     PrintSystemError(errno);
+    if (-1 == munmap(nmem, size)) PrintSystemError(errno);
     return -1;
   }
   memcpy(tmem, nmem, size);
@@ -380,6 +380,7 @@ MoveTextRegionToLargePages(const text_region& r) {
     if (ret == -1) {
       PrintSystemError(errno);
     }
+    if (-1 == munmap(nmem, size)) PrintSystemError(errno);
     return -1;
   }
   memcpy(start, tmem, size);
@@ -392,8 +393,10 @@ MoveTextRegionToLargePages(const text_region& r) {
     if (ret == -1) {
       PrintSystemError(errno);
     }
+    if (-1 == munmap(nmem, size)) PrintSystemError(errno);
     return -1;
   }
+  if (-1 == munmap(nmem, size)) PrintSystemError(errno);
   return ret;
 }
 
@@ -405,12 +408,12 @@ int MapStaticCodeToLargePages() {
     return -1;
   }
 
-#if defined(__linux__)
+#if defined(__linux__) || defined(__FreeBSD__)
   if (r.from > reinterpret_cast<void*>(&MoveTextRegionToLargePages))
     return MoveTextRegionToLargePages(r);
 
   return -1;
-#elif defined(__FreeBSD__) || defined(__APPLE__)
+#elif defined(__APPLE__)
   return MoveTextRegionToLargePages(r);
 #endif
 }
diff --git a/src/node.cc b/src/node.cc
index fee485f86e17f1..19f329d9a54e81 100644
--- a/src/node.cc
+++ b/src/node.cc
@@ -64,9 +64,7 @@
 #include "inspector/worker_inspector.h"  // ParentInspectorHandle
 #endif
 
-#ifdef NODE_ENABLE_LARGE_CODE_PAGES
 #include "large_pages/node_large_page.h"
-#endif
 
 #ifdef NODE_REPORT
 #include "node_report.h"
@@ -871,14 +869,6 @@ InitializationResult InitializeOncePerProcess(int argc, char** argv) {
 
   CHECK_GT(argc, 0);
 
-#ifdef NODE_ENABLE_LARGE_CODE_PAGES
-  if (node::IsLargePagesEnabled()) {
-    if (node::MapStaticCodeToLargePages() != 0) {
-      fprintf(stderr, "Reverting to default page size\n");
-    }
-  }
-#endif
-
   // Hack around with the argv pointer. Used for process.title = "blah".
   argv = uv_setup_args(argc, argv);
 
@@ -898,6 +888,26 @@ InitializationResult InitializeOncePerProcess(int argc, char** argv) {
     }
   }
 
+#if defined(NODE_ENABLE_LARGE_CODE_PAGES) && NODE_ENABLE_LARGE_CODE_PAGES
+  if (per_process::cli_options->use_largepages == "on" ||
+      per_process::cli_options->use_largepages == "silent") {
+    if (node::IsLargePagesEnabled()) {
+      if (node::MapStaticCodeToLargePages() != 0 &&
+          per_process::cli_options->use_largepages != "silent") {
+        fprintf(stderr,
+                "Mapping code to large pages failed. Reverting to default page "
+                "size.\n");
+      }
+    } else if (per_process::cli_options->use_largepages != "silent") {
+      fprintf(stderr, "Large pages are not enabled.\n");
+    }
+  }
+#else
+  if (per_process::cli_options->use_largepages == "on") {
+    fprintf(stderr, "Mapping to large pages is not supported.\n");
+  }
+#endif  // NODE_ENABLE_LARGE_CODE_PAGES
+
   if (per_process::cli_options->print_version) {
     printf("%s\n", NODE_VERSION);
     result.exit_code = 0;
diff --git a/src/node_options.cc b/src/node_options.cc
index 695935e2774a91..b1474cc25957dc 100644
--- a/src/node_options.cc
+++ b/src/node_options.cc
@@ -66,6 +66,11 @@ void PerProcessOptions::CheckOptions(std::vector<std::string>* errors) {
                       "used, not both");
   }
 #endif
+  if (use_largepages != "off" &&
+      use_largepages != "on" &&
+      use_largepages != "silent") {
+    errors->push_back("invalid value for --use-largepages");
+  }
   per_isolate->CheckOptions(errors);
 }
 
@@ -801,6 +806,10 @@ PerProcessOptionsParser::PerProcessOptionsParser(
             kAllowedInEnvironment);
 #endif
 #endif
+  AddOption("--use-largepages",
+            "Map the Node.js static code to large pages",
+            &PerProcessOptions::use_largepages,
+            kAllowedInEnvironment);
 
   // v12.x backwards compat flags removed in V8 7.9.
   AddOption("--fast_calls_with_arguments_mismatches", "", NoOp{});
diff --git a/src/node_options.h b/src/node_options.h
index 571ac305f9990c..476659027429e1 100644
--- a/src/node_options.h
+++ b/src/node_options.h
@@ -239,6 +239,7 @@ class PerProcessOptions : public Options {
   bool force_fips_crypto = false;
 #endif
 #endif
+  std::string use_largepages = "off";
 
 #ifdef NODE_REPORT
   std::vector<std::string> cmdline;
diff --git a/test/parallel/test-startup-large-pages.js b/test/parallel/test-startup-large-pages.js
new file mode 100644
index 00000000000000..d5589ee547f760
--- /dev/null
+++ b/test/parallel/test-startup-large-pages.js
@@ -0,0 +1,29 @@
+'use strict';
+
+// Make sure that Node.js runs correctly with the --use-largepages option.
+
+require('../common');
+const assert = require('assert');
+const { spawnSync } = require('child_process');
+
+{
+  const child = spawnSync(process.execPath,
+                          [ '--use-largepages=on', '-p', '42' ]);
+  const stdout = child.stdout.toString().match(/\S+/g);
+  assert.strictEqual(child.status, 0);
+  assert.strictEqual(child.signal, null);
+  assert.strictEqual(stdout.length, 1);
+  assert.strictEqual(stdout[0], '42');
+}
+
+{
+  const child = spawnSync(process.execPath,
+                          [ '--use-largepages=xyzzy', '-p', '42' ]);
+  assert.strictEqual(child.status, 9);
+  assert.strictEqual(child.signal, null);
+  assert.strictEqual(child.stderr.toString().match(/\S+/g).slice(1).join(' '),
+                     'invalid value for --use-largepages');
+}
+
+// TODO(gabrielschulhof): Make assertions about the stderr, which may or may not
+// contain a message indicating that mapping to large pages has failed.

From db8f1b0cf3053ba4b096ab29c6c88f4547130733 Mon Sep 17 00:00:00 2001
From: Gabriel Schulhof <gabriel.schulhof@intel.com>
Date: Mon, 23 Dec 2019 18:20:45 -0800
Subject: [PATCH 2/9] build: re-introduce --use-largepages as no-op

Re-introduce the build-time option as a no-op in order to retain
backward compatibility for LTS purposes.

Re: https://github.com/nodejs/node/pull/31063#pullrequestreview-336045756
PR_URL: https://github.com/nodejs/node/pull/31075
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Richard Lau <riclau@uk.ibm.com>
Reviewed-By: Beth Griggs <Bethany.Griggs@uk.ibm.com>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
---
 configure.py | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/configure.py b/configure.py
index e53d7d86843d84..6f0d30cae23434 100755
--- a/configure.py
+++ b/configure.py
@@ -424,6 +424,16 @@
     dest='with_etw',
     help='build with ETW (default is true on Windows)')
 
+parser.add_option('--use-largepages',
+    action='store_true',
+    dest='node_use_large_pages',
+    help='This option has no effect. --use-largepages is now a runtime option.')
+
+parser.add_option('--use-largepages-script-lld',
+    action='store_true',
+    dest='node_use_large_pages_script_lld',
+    help='This option has no effect. --use-largepages is now a runtime option.')
+
 intl_optgroup.add_option('--with-intl',
     action='store',
     dest='with_intl',

From 17fa34c6fb197a94d5c2d4cfa8e02a999fe9eeda Mon Sep 17 00:00:00 2001
From: bcoe <bencoe@google.com>
Date: Wed, 25 Dec 2019 16:22:21 -0800
Subject: [PATCH 3/9] build: switch realpath to pwd

PR-URL: https://github.com/nodejs/node/pull/31095
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Gabriel Schulhof <gabriel.schulhof@intel.com>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
---
 node.gypi | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/node.gypi b/node.gypi
index cc4f2216764b16..a22800af0903ce 100644
--- a/node.gypi
+++ b/node.gypi
@@ -322,7 +322,7 @@
       'llvm_version=="0.0"', {
       'ldflags': [
         '-Wl,-T',
-        '<!(realpath src/large_pages/ld.implicit.script)',
+        '<!(echo "$(pwd)/src/large_pages/ld.implicit.script")',
       ]
     }],
     [ 'OS=="linux" and '
@@ -330,7 +330,7 @@
       'llvm_version!="0.0"', {
       'ldflags': [
         '-Wl,-T',
-        '<!(realpath src/large_pages/ld.implicit.script.lld)',
+        '<!(echo "$(pwd)/src/large_pages/ld.implicit.script.lld")',
       ]
     }],
     [ 'node_use_openssl=="true"', {

From 58ab4b586b9ff550e92e7dc97f50b639b208a17d Mon Sep 17 00:00:00 2001
From: Denys Otrishko <shishugi@gmail.com>
Date: Tue, 24 Dec 2019 13:42:48 +0200
Subject: [PATCH 4/9] src: make large_pages node.cc include conditional

The usage of the relevant methods from the file is conditional so make
the include conditional too.

PR-URL: https://github.com/nodejs/node/pull/31078
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Richard Lau <riclau@uk.ibm.com>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
Reviewed-By: David Carlier <devnexen@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>
---
 src/node.cc | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/node.cc b/src/node.cc
index 19f329d9a54e81..c4945e9737330c 100644
--- a/src/node.cc
+++ b/src/node.cc
@@ -64,7 +64,9 @@
 #include "inspector/worker_inspector.h"  // ParentInspectorHandle
 #endif
 
+#ifdef NODE_ENABLE_LARGE_CODE_PAGES
 #include "large_pages/node_large_page.h"
+#endif
 
 #ifdef NODE_REPORT
 #include "node_report.h"

From d8bdf4e049e0a87bb27befd7bd79ba447e3f29b5 Mon Sep 17 00:00:00 2001
From: Gabriel Schulhof <gabriel.schulhof@intel.com>
Date: Thu, 26 Dec 2019 09:04:43 -0800
Subject: [PATCH 5/9] build: warn upon --use-largepages config option

Emit a warning when the user configures with `--use-largepages` and/or
`--use-largepages-script-lld` informing them that the option is now
available as a Node.js runtime option once it is built.

Refs: https://github.com/nodejs/node/pull/31063#discussion_r361143460
PR-URL: https://github.com/nodejs/node/pull/31103
Reviewed-By: Richard Lau <riclau@uk.ibm.com>
Reviewed-By: Denys Otrishko <shishugi@gmail.com>
---
 configure.py | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/configure.py b/configure.py
index 6f0d30cae23434..05db673a496637 100755
--- a/configure.py
+++ b/configure.py
@@ -1091,6 +1091,13 @@ def configure_node(o):
   else:
     o['variables']['node_use_dtrace'] = 'false'
 
+  if options.node_use_large_pages or options.node_use_large_pages_script_lld:
+    warn('''The `--use-largepages` and `--use-largepages-script-lld` options
+         have no effect during build time. Support for mapping to large pages is
+         now a runtime option of Node.js. Run `node --use-largepages` or add
+         `--use-largepages` to the `NODE_OPTIONS` environment variable once
+         Node.js is built to enable mapping to large pages.''')
+
   if options.no_ifaddrs:
     o['defines'] += ['SUNOS_NO_IFADDRS']
 

From ccadc89b4585afda228daeb340340093cffcfa5e Mon Sep 17 00:00:00 2001
From: Ben Noordhuis <info@bnoordhuis.nl>
Date: Tue, 28 Jan 2020 11:01:32 +0100
Subject: [PATCH 6/9] src: use __executable_start for linux hugepages

`__executable_start` is provided by GNU's and LLVM's default linker
scripts, obviating the need to plug in a custom linker script.

The problem with our bespoke linker script is that it works with ld.bfd
but not ld.gold and cannot easily be ported because the latter linker
doesn't understand the `INSERT BEFORE` directive.

The /proc/self/maps scanner is updated to account for the fact that
there are a number of sections between `&__executable_start` and
the start of the .text section.

Fortunately, those sections are all mapped into the same memory segment
so we only need to look at the next line to find the start of our text
segment.

Fixes: https://github.com/nodejs/node/issues/31520

PR-URL: https://github.com/nodejs/node/pull/31547
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Gus Caplan <me@gus.host>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: David Carlier <devnexen@gmail.com>
---
 node.gyp                               |  3 +-
 node.gypi                              | 16 -----
 src/large_pages/ld.implicit.script     | 10 ----
 src/large_pages/ld.implicit.script.lld |  3 -
 src/large_pages/node_large_page.cc     | 83 ++++++++++++++------------
 5 files changed, 47 insertions(+), 68 deletions(-)
 delete mode 100644 src/large_pages/ld.implicit.script
 delete mode 100644 src/large_pages/ld.implicit.script.lld

diff --git a/node.gyp b/node.gyp
index a0b7f25a75d059..5727d76dbcfc9b 100644
--- a/node.gyp
+++ b/node.gyp
@@ -847,7 +847,8 @@
           ],
         }],
         [ 'OS in "linux freebsd mac" and '
-          'target_arch=="x64"', {
+          'target_arch=="x64" and '
+          'node_target_type=="executable"', {
           'defines': [ 'NODE_ENABLE_LARGE_CODE_PAGES=1' ],
           'sources': [
             'src/large_pages/node_large_page.cc',
diff --git a/node.gypi b/node.gypi
index a22800af0903ce..116c1c7149425b 100644
--- a/node.gypi
+++ b/node.gypi
@@ -317,22 +317,6 @@
       'ldflags': [ '-Wl,-z,relro',
                    '-Wl,-z,now' ]
     }],
-    [ 'OS=="linux" and '
-      'target_arch=="x64" and '
-      'llvm_version=="0.0"', {
-      'ldflags': [
-        '-Wl,-T',
-        '<!(echo "$(pwd)/src/large_pages/ld.implicit.script")',
-      ]
-    }],
-    [ 'OS=="linux" and '
-      'target_arch=="x64" and '
-      'llvm_version!="0.0"', {
-      'ldflags': [
-        '-Wl,-T',
-        '<!(echo "$(pwd)/src/large_pages/ld.implicit.script.lld")',
-      ]
-    }],
     [ 'node_use_openssl=="true"', {
       'defines': [ 'HAVE_OPENSSL=1' ],
       'conditions': [
diff --git a/src/large_pages/ld.implicit.script b/src/large_pages/ld.implicit.script
deleted file mode 100644
index 7f12e4bd7df9e5..00000000000000
--- a/src/large_pages/ld.implicit.script
+++ /dev/null
@@ -1,10 +0,0 @@
-  SECTIONS {
-    .lpstub            : {
-       *libc.a:*(.text .text.*)
-       *(.lpstub)
-     }
-  }
-  PROVIDE (__nodetext = .);
-  PROVIDE (_nodetext = .);
-  PROVIDE (nodetext = .);
-  INSERT BEFORE .text;
diff --git a/src/large_pages/ld.implicit.script.lld b/src/large_pages/ld.implicit.script.lld
deleted file mode 100644
index b85510bcf07eeb..00000000000000
--- a/src/large_pages/ld.implicit.script.lld
+++ /dev/null
@@ -1,3 +0,0 @@
-  PROVIDE (__nodetext = .);
-  PROVIDE (_nodetext = .);
-  PROVIDE (nodetext = .);
diff --git a/src/large_pages/node_large_page.cc b/src/large_pages/node_large_page.cc
index 252ccba15780d6..ce58e32e719bc8 100644
--- a/src/large_pages/node_large_page.cc
+++ b/src/large_pages/node_large_page.cc
@@ -65,7 +65,11 @@
 // Use madvise with MADV_HUGEPAGE to use Anonymous 2M Pages
 // If successful copy the code there and unmap the original region.
 
-extern char __nodetext;
+#if defined(__linux__)
+extern "C" {
+extern char __executable_start;
+}  // extern "C"
+#endif  // defined(__linux__)
 
 namespace node {
 
@@ -116,17 +120,6 @@ static struct text_region FindNodeTextRegion() {
     return nregion;
   }
 
-  std::string exename;
-  {
-      char selfexe[PATH_MAX];
-
-      size_t size = sizeof(selfexe);
-      if (uv_exepath(selfexe, &size))
-        return nregion;
-
-      exename = std::string(selfexe, size);
-  }
-
   while (std::getline(ifs, map_line)) {
     std::istringstream iss(map_line);
     iss >> std::hex >> start;
@@ -136,26 +129,42 @@ static struct text_region FindNodeTextRegion() {
     iss >> offset;
     iss >> dev;
     iss >> inode;
-    if (inode != 0) {
-      std::string pathname;
-      iss >> pathname;
-      if (pathname == exename && permission == "r-xp") {
-        uintptr_t ntext = reinterpret_cast<uintptr_t>(&__nodetext);
-        if (ntext >= start && ntext < end) {
-          char* from = reinterpret_cast<char*>(hugepage_align_up(ntext));
-          char* to = reinterpret_cast<char*>(hugepage_align_down(end));
-
-          if (from < to) {
-            size_t size = to - from;
-            nregion.found_text_region = true;
-            nregion.from = from;
-            nregion.to = to;
-            nregion.total_hugepages = size / hps;
-          }
-          break;
-        }
-      }
-    }
+
+    if (inode == 0)
+      continue;
+
+    std::string pathname;
+    iss >> pathname;
+
+    if (start != reinterpret_cast<uintptr_t>(&__executable_start))
+      continue;
+
+    // The next line is our .text section.
+    if (!std::getline(ifs, map_line))
+      break;
+
+    iss = std::istringstream(map_line);
+    iss >> std::hex >> start;
+    iss >> dash;
+    iss >> std::hex >> end;
+    iss >> permission;
+
+    if (permission != "r-xp")
+      break;
+
+    char* from = reinterpret_cast<char*>(hugepage_align_up(start));
+    char* to = reinterpret_cast<char*>(hugepage_align_down(end));
+
+    if (from >= to)
+      break;
+
+    size_t size = to - from;
+    nregion.found_text_region = true;
+    nregion.from = from;
+    nregion.to = to;
+    nregion.total_hugepages = size / hps;
+
+    break;
   }
 
   ifs.close();
@@ -408,14 +417,12 @@ int MapStaticCodeToLargePages() {
     return -1;
   }
 
-#if defined(__linux__) || defined(__FreeBSD__)
-  if (r.from > reinterpret_cast<void*>(&MoveTextRegionToLargePages))
-    return MoveTextRegionToLargePages(r);
+#if defined(__FreeBSD__)
+  if (r.from < reinterpret_cast<void*>(&MoveTextRegionToLargePages))
+    return -1;
+#endif
 
-  return -1;
-#elif defined(__APPLE__)
   return MoveTextRegionToLargePages(r);
-#endif
 }
 
 bool IsLargePagesEnabled() {

From 2f3d446a846a0044521a4c00ccbbda6e9d1d103c Mon Sep 17 00:00:00 2001
From: Gabriel Schulhof <gabriel.schulhof@intel.com>
Date: Fri, 21 Feb 2020 08:26:29 -0800
Subject: [PATCH 7/9] src: include large pages source unconditionally

Restrict the usage of the C preprocessor directive enabling large
pages support to the large pages implementation. This cleans up the
code in src/node.cc.

PR-URL: https://github.com/nodejs/node/pull/31904
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: David Carlier <devnexen@gmail.com>
Reviewed-By: Denys Otrishko <shishugi@gmail.com>
---
 node.gyp                           |  6 +--
 src/large_pages/node_large_page.cc | 69 +++++++++++++++++++++++-------
 src/large_pages/node_large_page.h  |  3 +-
 src/node.cc                        | 20 ++-------
 4 files changed, 59 insertions(+), 39 deletions(-)

diff --git a/node.gyp b/node.gyp
index 5727d76dbcfc9b..695476811d8569 100644
--- a/node.gyp
+++ b/node.gyp
@@ -617,6 +617,8 @@
         'src/histogram-inl.h',
         'src/http_parser_adaptor.h',
         'src/js_stream.h',
+        'src/large_pages/node_large_page.cc',
+        'src/large_pages/node_large_page.h'
         'src/memory_tracker.h',
         'src/memory_tracker-inl.h',
         'src/module_wrap.h',
@@ -850,10 +852,6 @@
           'target_arch=="x64" and '
           'node_target_type=="executable"', {
           'defines': [ 'NODE_ENABLE_LARGE_CODE_PAGES=1' ],
-          'sources': [
-            'src/large_pages/node_large_page.cc',
-            'src/large_pages/node_large_page.h'
-          ],
         }],
         [ 'use_openssl_def==1', {
           # TODO(bnoordhuis) Make all platforms export the same list of symbols.
diff --git a/src/large_pages/node_large_page.cc b/src/large_pages/node_large_page.cc
index ce58e32e719bc8..a72cb65bb65674 100644
--- a/src/large_pages/node_large_page.cc
+++ b/src/large_pages/node_large_page.cc
@@ -21,6 +21,11 @@
 // SPDX-License-Identifier: MIT
 
 #include "node_large_page.h"
+
+#include <cerrno>   // NOLINT(build/include)
+
+// Besides returning ENOTSUP at runtime we do nothing if this define is missing.
+#if defined(NODE_ENABLE_LARGE_CODE_PAGES) && NODE_ENABLE_LARGE_CODE_PAGES
 #include "util.h"
 #include "uv.h"
 
@@ -35,7 +40,6 @@
 #endif
 #include <unistd.h>  // readlink
 
-#include <cerrno>   // NOLINT(build/include)
 #include <climits>  // PATH_MAX
 #include <clocale>
 #include <csignal>
@@ -71,7 +75,11 @@ extern char __executable_start;
 }  // extern "C"
 #endif  // defined(__linux__)
 
+#endif  // defined(NODE_ENABLE_LARGE_CODE_PAGES) && NODE_ENABLE_LARGE_CODE_PAGES
 namespace node {
+#if defined(NODE_ENABLE_LARGE_CODE_PAGES) && NODE_ENABLE_LARGE_CODE_PAGES
+
+namespace {
 
 struct text_region {
   char* from;
@@ -103,7 +111,7 @@ inline uintptr_t hugepage_align_down(uintptr_t addr) {
 // 00400000-00452000 r-xp 00000000 08:02 173521      /usr/bin/dbus-daemon
 // This is also handling the case where the first line is not the binary.
 
-static struct text_region FindNodeTextRegion() {
+struct text_region FindNodeTextRegion() {
   struct text_region nregion;
   nregion.found_text_region = false;
 #if defined(__linux__)
@@ -263,7 +271,7 @@ static struct text_region FindNodeTextRegion() {
 }
 
 #if defined(__linux__)
-static bool IsTransparentHugePagesEnabled() {
+bool IsTransparentHugePagesEnabled() {
   std::ifstream ifs;
 
   ifs.open("/sys/kernel/mm/transparent_hugepage/enabled");
@@ -294,6 +302,8 @@ static bool IsSuperPagesEnabled() {
 }
 #endif
 
+}  // End of anonymous namespace
+
 // Moving the text region to large pages. We need to be very careful.
 // 1: This function itself should not be moved.
 // We use a gcc attributes
@@ -408,14 +418,26 @@ MoveTextRegionToLargePages(const text_region& r) {
   if (-1 == munmap(nmem, size)) PrintSystemError(errno);
   return ret;
 }
+#endif  // defined(NODE_ENABLE_LARGE_CODE_PAGES) && NODE_ENABLE_LARGE_CODE_PAGES
 
 // This is the primary API called from main.
 int MapStaticCodeToLargePages() {
+#if defined(NODE_ENABLE_LARGE_CODE_PAGES) && NODE_ENABLE_LARGE_CODE_PAGES
+  bool have_thp = false;
+#if defined(__linux__)
+  have_thp = IsTransparentHugePagesEnabled();
+#elif defined(__FreeBSD__)
+  have_thp = IsSuperPagesEnabled();
+#elif defined(__APPLE__)
+  // pse-36 flag is present in recent mac x64 products.
+  have_thp = true;
+#endif
+  if (!have_thp)
+    return EACCES;
+
   struct text_region r = FindNodeTextRegion();
-  if (r.found_text_region == false) {
-    PrintWarning("failed to find text region");
-    return -1;
-  }
+  if (r.found_text_region == false)
+    return ENOENT;
 
 #if defined(__FreeBSD__)
   if (r.from < reinterpret_cast<void*>(&MoveTextRegionToLargePages))
@@ -423,17 +445,32 @@ int MapStaticCodeToLargePages() {
 #endif
 
   return MoveTextRegionToLargePages(r);
+#else
+  return ENOTSUP;
+#endif
 }
 
-bool IsLargePagesEnabled() {
-#if defined(__linux__)
-  return IsTransparentHugePagesEnabled();
-#elif defined(__FreeBSD__)
-  return IsSuperPagesEnabled();
-#elif defined(__APPLE__)
-  // pse-36 flag is present in recent mac x64 products.
-  return true;
-#endif
+const char* LargePagesError(int status) {
+  switch (status) {
+    case ENOTSUP:
+      return "Mapping to large pages is not supported.";
+
+    case EACCES:
+      return "Large pages are not enabled.";
+
+    case ENOENT:
+      return "failed to find text region";
+
+    case -1:
+      return "Mapping code to large pages failed. Reverting to default page "
+          "size.";
+
+    case 0:
+      return "OK";
+
+    default:
+      return "Unknown error";
+  }
 }
 
 }  // namespace node
diff --git a/src/large_pages/node_large_page.h b/src/large_pages/node_large_page.h
index bce505585cf0d0..622cf09ede4e1c 100644
--- a/src/large_pages/node_large_page.h
+++ b/src/large_pages/node_large_page.h
@@ -25,10 +25,9 @@
 
 #if defined(NODE_WANT_INTERNALS) && NODE_WANT_INTERNALS
 
-
 namespace node {
-bool IsLargePagesEnabled();
 int MapStaticCodeToLargePages();
+const char* LargePagesError(int status);
 }  // namespace node
 
 #endif  // NODE_WANT_INTERNALS
diff --git a/src/node.cc b/src/node.cc
index c4945e9737330c..2b6f92149efe90 100644
--- a/src/node.cc
+++ b/src/node.cc
@@ -64,9 +64,7 @@
 #include "inspector/worker_inspector.h"  // ParentInspectorHandle
 #endif
 
-#ifdef NODE_ENABLE_LARGE_CODE_PAGES
 #include "large_pages/node_large_page.h"
-#endif
 
 #ifdef NODE_REPORT
 #include "node_report.h"
@@ -890,25 +888,13 @@ InitializationResult InitializeOncePerProcess(int argc, char** argv) {
     }
   }
 
-#if defined(NODE_ENABLE_LARGE_CODE_PAGES) && NODE_ENABLE_LARGE_CODE_PAGES
   if (per_process::cli_options->use_largepages == "on" ||
       per_process::cli_options->use_largepages == "silent") {
-    if (node::IsLargePagesEnabled()) {
-      if (node::MapStaticCodeToLargePages() != 0 &&
-          per_process::cli_options->use_largepages != "silent") {
-        fprintf(stderr,
-                "Mapping code to large pages failed. Reverting to default page "
-                "size.\n");
-      }
-    } else if (per_process::cli_options->use_largepages != "silent") {
-      fprintf(stderr, "Large pages are not enabled.\n");
+    int result = node::MapStaticCodeToLargePages();
+    if (per_process::cli_options->use_largepages == "on" && result != 0) {
+      fprintf(stderr, "%s\n", node::LargePagesError(result));
     }
   }
-#else
-  if (per_process::cli_options->use_largepages == "on") {
-    fprintf(stderr, "Mapping to large pages is not supported.\n");
-  }
-#endif  // NODE_ENABLE_LARGE_CODE_PAGES
 
   if (per_process::cli_options->print_version) {
     printf("%s\n", NODE_VERSION);

From f2572a1b078ddb192e6be8a3b85b9a5a466ee712 Mon Sep 17 00:00:00 2001
From: Gabriel Schulhof <gabriel.schulhof@intel.com>
Date: Wed, 26 Feb 2020 16:21:41 -0800
Subject: [PATCH 8/9] src: start the .text section with an asm symbol

We create an object file in assembly which introduces the symbol
`__node_text_start` into the .text section and place the resulting
object file as the first file the linker encounters. We do this to
ensure that we can recognize the boundaries of the .text section when
attempting to establish the address range to map to large pages.

Additionally, we rename the section containing the remapping code from
`.lpstub` to `lpstub` so as to take advantage of the linker's feature
whereby it inserts the symbol `__start_lpstub` when the section's name
can be rendered as a valid C variable. We need this symbol in order to
avoid self-mapping the remapping code to large pages, because doing so
would cause the process to crash.

PR-URL: https://github.com/nodejs/node/pull/31981
Reviewed-By: Franziska Hinkelmann <franziska.hinkelmann@gmail.com>
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: David Carlier <devnexen@gmail.com>
Signed-off-by: Gabriel Schulhof <gabriel.schulhof@intel.com>
---
 node.gyp                           | 20 ++++++++++++++++++++
 src/large_pages/node_large_page.cc | 28 ++++++++++++++--------------
 src/large_pages/node_text_start.S  |  5 +++++
 3 files changed, 39 insertions(+), 14 deletions(-)
 create mode 100644 src/large_pages/node_text_start.S

diff --git a/node.gyp b/node.gyp
index 695476811d8569..b63bc44061620b 100644
--- a/node.gyp
+++ b/node.gyp
@@ -307,6 +307,19 @@
   },
 
   'targets': [
+    {
+      'target_name': 'node_text_start',
+      'type': 'none',
+      'conditions': [
+        [ 'OS=="linux" and '
+          'target_arch=="x64"', {
+          'type': 'static_library',
+          'sources': [
+            'src/large_pages/node_text_start.S'
+          ]
+        }],
+      ]
+    },
     {
       'target_name': '<(node_core_target_name)',
       'type': 'executable',
@@ -492,6 +505,13 @@
             'src/node_snapshot_stub.cc'
           ],
         }],
+        [ 'OS=="linux" and '
+          'target_arch=="x64"', {
+          'dependencies': [ 'node_text_start' ],
+          'ldflags+': [
+            '<(PRODUCT_DIR)/obj.target/node_text_start/src/large_pages/node_text_start.o'
+          ]
+        }],
       ],
     }, # node_core_target_name
     {
diff --git a/src/large_pages/node_large_page.cc b/src/large_pages/node_large_page.cc
index a72cb65bb65674..31d85c1734a63c 100644
--- a/src/large_pages/node_large_page.cc
+++ b/src/large_pages/node_large_page.cc
@@ -71,7 +71,11 @@
 
 #if defined(__linux__)
 extern "C" {
-extern char __executable_start;
+// This symbol must be declared weak because this file becomes part of all
+// Node.js targets (like node_mksnapshot, node_mkcodecache, and cctest) and
+// those files do not supply the symbol.
+extern char __attribute__((weak)) __node_text_start;
+extern char __start_lpstub;
 }  // extern "C"
 #endif  // defined(__linux__)
 
@@ -121,6 +125,8 @@ struct text_region FindNodeTextRegion() {
   std::string dev;
   char dash;
   uintptr_t start, end, offset, inode;
+  uintptr_t node_text_start = reinterpret_cast<uintptr_t>(&__node_text_start);
+  uintptr_t lpstub_start = reinterpret_cast<uintptr_t>(&__start_lpstub);
 
   ifs.open("/proc/self/maps");
   if (!ifs) {
@@ -144,21 +150,15 @@ struct text_region FindNodeTextRegion() {
     std::string pathname;
     iss >> pathname;
 
-    if (start != reinterpret_cast<uintptr_t>(&__executable_start))
+    if (permission != "r-xp")
       continue;
 
-    // The next line is our .text section.
-    if (!std::getline(ifs, map_line))
-      break;
-
-    iss = std::istringstream(map_line);
-    iss >> std::hex >> start;
-    iss >> dash;
-    iss >> std::hex >> end;
-    iss >> permission;
+    if (node_text_start < start || node_text_start >= end)
+      continue;
 
-    if (permission != "r-xp")
-      break;
+    start = node_text_start;
+    if (lpstub_start > start && lpstub_start <= end)
+      end = lpstub_start;
 
     char* from = reinterpret_cast<char*>(hugepage_align_up(start));
     char* to = reinterpret_cast<char*>(hugepage_align_down(end));
@@ -318,7 +318,7 @@ static bool IsSuperPagesEnabled() {
 // d. If successful copy the code there and unmap the original region
 int
 #if !defined(__APPLE__)
-__attribute__((__section__(".lpstub")))
+__attribute__((__section__("lpstub")))
 #else
 __attribute__((__section__("__TEXT,__lpstub")))
 #endif
diff --git a/src/large_pages/node_text_start.S b/src/large_pages/node_text_start.S
new file mode 100644
index 00000000000000..1609b254f0495a
--- /dev/null
+++ b/src/large_pages/node_text_start.S
@@ -0,0 +1,5 @@
+.text
+.align 0x2000
+.global __node_text_start
+.hidden __node_text_start
+__node_text_start:

From 0c391fb510e3ba51cb1d69dbe8b3979490ffa696 Mon Sep 17 00:00:00 2001
From: Richard Lau <riclau@uk.ibm.com>
Date: Tue, 3 Mar 2020 15:02:02 -0500
Subject: [PATCH 9/9] build: fix building with ninja

The ninja build places objects in a different directory.

Co-authored-by: Gabriel Schulhof <gabriel.schulhof@intel.com>
Signed-off-by: Richard Lau <riclau@uk.ibm.com>

PR-URL: https://github.com/nodejs/node/pull/32071
Reviewed-By: Matheus Marchini <mat@mmarchini.me>
Reviewed-By: Gabriel Schulhof <gabriel.schulhof@intel.com>
Reviewed-By: Sam Roberts <vieuxtech@gmail.com>
Reviewed-By: Shelley Vohr <codebytere@gmail.com>
Reviewed-By: Myles Borins <myles.borins@gmail.com>
Reviewed-By: Jiawen Geng <technicalcute@gmail.com>
---
 node.gyp | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/node.gyp b/node.gyp
index b63bc44061620b..4599a02195bcf6 100644
--- a/node.gyp
+++ b/node.gyp
@@ -244,6 +244,11 @@
     'node_mksnapshot_exec': '<(PRODUCT_DIR)/<(EXECUTABLE_PREFIX)node_mksnapshot<(EXECUTABLE_SUFFIX)',
     'mkcodecache_exec': '<(PRODUCT_DIR)/<(EXECUTABLE_PREFIX)mkcodecache<(EXECUTABLE_SUFFIX)',
     'conditions': [
+      ['GENERATOR == "ninja"', {
+        'node_text_start_object_path': 'src/large_pages/node_text_start.node_text_start.o'
+      }, {
+        'node_text_start_object_path': 'node_text_start/src/large_pages/node_text_start.o'
+      }],
       [ 'node_shared=="true"', {
         'node_target_type%': 'shared_library',
         'conditions': [
@@ -509,7 +514,7 @@
           'target_arch=="x64"', {
           'dependencies': [ 'node_text_start' ],
           'ldflags+': [
-            '<(PRODUCT_DIR)/obj.target/node_text_start/src/large_pages/node_text_start.o'
+            '<(obj_dir)/<(node_text_start_object_path)'
           ]
         }],
       ],