[dpdk-dev] [PATCH v5 10/11] eal/windows: initialize hugepage info

[Dmitry Kozlyuk <dmitry.kozliuk@gmail.com>]

Add hugepages discovery ("large pages" in Windows terminology)
and update documentation for required privilege setup. Only 2MB
hugepages are supported and their number is estimated roughly
due to the lack or unstable status of suitable OS APIs.

Signed-off-by: Dmitry Kozlyuk <dmitry.kozliuk@gmail.com>
---
 config/meson.build                     |   2 +
 doc/guides/windows_gsg/build_dpdk.rst  |  20 -----
 doc/guides/windows_gsg/index.rst       |   1 +
 doc/guides/windows_gsg/run_apps.rst    |  47 +++++++++++
 lib/librte_eal/windows/eal.c           |  14 ++++
 lib/librte_eal/windows/eal_hugepages.c | 108 +++++++++++++++++++++++++
 lib/librte_eal/windows/meson.build     |   1 +
 7 files changed, 173 insertions(+), 20 deletions(-)
 create mode 100644 doc/guides/windows_gsg/run_apps.rst
 create mode 100644 lib/librte_eal/windows/eal_hugepages.c

diff --git a/config/meson.build b/config/meson.build
index 43ab11310..c1e80de4b 100644
--- a/config/meson.build
+++ b/config/meson.build
@@ -268,6 +268,8 @@ if is_windows
 	if cc.get_id() == 'gcc'
 		add_project_arguments('-D__USE_MINGW_ANSI_STDIO', language: 'c')
 	endif
+
+	add_project_link_arguments('-ladvapi32', language: 'c')
 endif
 
 if get_option('b_lto')
diff --git a/doc/guides/windows_gsg/build_dpdk.rst b/doc/guides/windows_gsg/build_dpdk.rst
index d46e84e3f..650483e3b 100644
--- a/doc/guides/windows_gsg/build_dpdk.rst
+++ b/doc/guides/windows_gsg/build_dpdk.rst
@@ -111,23 +111,3 @@ Depending on the distribution, paths in this file may need adjustments.
 
     meson --cross-file config/x86/meson_mingw.txt -Dexamples=helloworld build
     ninja -C build
-
-
-Run the helloworld example
-==========================
-
-Navigate to the examples in the build directory and run `dpdk-helloworld.exe`.
-
-.. code-block:: console
-
-    cd C:\Users\me\dpdk\build\examples
-    dpdk-helloworld.exe
-    hello from core 1
-    hello from core 3
-    hello from core 0
-    hello from core 2
-
-Note for MinGW-w64: applications are linked to ``libwinpthread-1.dll``
-by default. To run the example, either add toolchain executables directory
-to the PATH or copy the library to the working directory.
-Alternatively, static linking may be used (mind the LGPLv2.1 license).
diff --git a/doc/guides/windows_gsg/index.rst b/doc/guides/windows_gsg/index.rst
index d9b7990a8..e94593572 100644
--- a/doc/guides/windows_gsg/index.rst
+++ b/doc/guides/windows_gsg/index.rst
@@ -12,3 +12,4 @@ Getting Started Guide for Windows
 
     intro
     build_dpdk
+    run_apps
diff --git a/doc/guides/windows_gsg/run_apps.rst b/doc/guides/windows_gsg/run_apps.rst
new file mode 100644
index 000000000..21ac7f6c1
--- /dev/null
+++ b/doc/guides/windows_gsg/run_apps.rst
@@ -0,0 +1,47 @@
+..  SPDX-License-Identifier: BSD-3-Clause
+    Copyright(c) 2020 Dmitry Kozlyuk
+
+Running DPDK Applications
+=========================
+
+Grant *Lock pages in memory* Privilege
+--------------------------------------
+
+Use of hugepages ("large pages" in Windows terminolocy) requires
+``SeLockMemoryPrivilege`` for the user running an application.
+
+1. Open *Local Security Policy* snap in, either:
+
+   * Control Panel / Computer Management / Local Security Policy;
+   * or Win+R, type ``secpol``, press Enter.
+
+2. Open *Local Policies / User Rights Assignment / Lock pages in memory.*
+
+3. Add desired users or groups to the list of grantees.
+
+4. Privilege is applied upon next logon. In particular, if privilege has been
+   granted to current user, a logoff is required before it is available.
+
+See `Large-Page Support`_ in MSDN for details.
+
+.. _Large-page Support: https://docs.microsoft.com/en-us/windows/win32/memory/large-page-support
+
+
+Run the ``helloworld`` Example
+------------------------------
+
+Navigate to the examples in the build directory and run `dpdk-helloworld.exe`.
+
+.. code-block:: console
+
+    cd C:\Users\me\dpdk\build\examples
+    dpdk-helloworld.exe
+    hello from core 1
+    hello from core 3
+    hello from core 0
+    hello from core 2
+
+Note for MinGW-w64: applications are linked to ``libwinpthread-1.dll``
+by default. To run the example, either add toolchain executables directory
+to the PATH or copy the library to the working directory.
+Alternatively, static linking may be used (mind the LGPLv2.1 license).
diff --git a/lib/librte_eal/windows/eal.c b/lib/librte_eal/windows/eal.c
index e7461f731..7c2fcc860 100644
--- a/lib/librte_eal/windows/eal.c
+++ b/lib/librte_eal/windows/eal.c
@@ -19,8 +19,11 @@
 #include <eal_private.h>
 #include <rte_trace_point.h>
 
+#include "eal_hugepages.h"
 #include "eal_windows.h"
 
+#define MEMSIZE_IF_NO_HUGE_PAGE (64ULL * 1024ULL * 1024ULL)
+
  /* Allow the application to print its usage message too if set */
 static rte_usage_hook_t	rte_application_usage_hook;
 
@@ -276,6 +279,17 @@ rte_eal_init(int argc, char **argv)
 	if (fctret < 0)
 		exit(1);
 
+	if (!internal_config.no_hugetlbfs && (eal_hugepage_info_init() < 0)) {
+		rte_eal_init_alert("Cannot get hugepage information");
+		rte_errno = EACCES;
+		return -1;
+	}
+
+	if (internal_config.memory == 0 && !internal_config.force_sockets) {
+		if (internal_config.no_hugetlbfs)
+			internal_config.memory = MEMSIZE_IF_NO_HUGE_PAGE;
+	}
+
 	eal_thread_init_master(rte_config.master_lcore);
 
 	RTE_LCORE_FOREACH_SLAVE(i) {
diff --git a/lib/librte_eal/windows/eal_hugepages.c b/lib/librte_eal/windows/eal_hugepages.c
new file mode 100644
index 000000000..61d0dcd3c
--- /dev/null
+++ b/lib/librte_eal/windows/eal_hugepages.c
@@ -0,0 +1,108 @@
+#include <rte_errno.h>
+#include <rte_log.h>
+#include <rte_memory.h>
+#include <rte_memzone.h>
+#include <rte_os.h>
+
+#include "eal_filesystem.h"
+#include "eal_hugepages.h"
+#include "eal_internal_cfg.h"
+#include "eal_windows.h"
+
+static int
+hugepage_claim_privilege(void)
+{
+	static const wchar_t privilege[] = L"SeLockMemoryPrivilege";
+
+	HANDLE token;
+	LUID luid;
+	TOKEN_PRIVILEGES tp;
+	int ret = -1;
+
+	if (!OpenProcessToken(GetCurrentProcess(),
+			TOKEN_ADJUST_PRIVILEGES, &token)) {
+		RTE_LOG_WIN32_ERR("OpenProcessToken()");
+		return -1;
+	}
+
+	if (!LookupPrivilegeValueW(NULL, privilege, &luid)) {
+		RTE_LOG_WIN32_ERR("LookupPrivilegeValue(\"%S\")", privilege);
+		goto exit;
+	}
+
+	tp.PrivilegeCount = 1;
+	tp.Privileges[0].Luid = luid;
+	tp.Privileges[0].Attributes = SE_PRIVILEGE_ENABLED;
+
+	if (!AdjustTokenPrivileges(
+			token, FALSE, &tp, sizeof(tp), NULL, NULL)) {
+		RTE_LOG_WIN32_ERR("AdjustTokenPrivileges()");
+		goto exit;
+	}
+
+	ret = 0;
+
+exit:
+	CloseHandle(token);
+
+	return ret;
+}
+
+static int
+hugepage_info_init(void)
+{
+	struct hugepage_info *hpi;
+	unsigned int socket_id;
+	int ret = 0;
+
+	/* Only one hugepage size available on Windows. */
+	internal_config.num_hugepage_sizes = 1;
+	hpi = &internal_config.hugepage_info[0];
+
+	hpi->hugepage_sz = GetLargePageMinimum();
+	if (hpi->hugepage_sz == 0)
+		return -ENOTSUP;
+
+	/* Assume all memory on each NUMA node available for hugepages,
+	 * because Windows neither advertises additional limits,
+	 * nor provides an API to query them.
+	 */
+	for (socket_id = 0; socket_id < rte_socket_count(); socket_id++) {
+		ULONGLONG bytes;
+		unsigned int numa_node;
+
+		numa_node = eal_socket_numa_node(socket_id);
+		if (!GetNumaAvailableMemoryNodeEx(numa_node, &bytes)) {
+			RTE_LOG_WIN32_ERR("GetNumaAvailableMemoryNodeEx(%u)",
+				numa_node);
+			continue;
+		}
+
+		hpi->num_pages[socket_id] = bytes / hpi->hugepage_sz;
+		RTE_LOG(DEBUG, EAL,
+			"Found %u hugepages of %zu bytes on socket %u\n",
+			hpi->num_pages[socket_id], hpi->hugepage_sz, socket_id);
+	}
+
+	/* No hugepage filesystem on Windows. */
+	hpi->lock_descriptor = -1;
+	memset(hpi->hugedir, 0, sizeof(hpi->hugedir));
+
+	return ret;
+}
+
+int
+eal_hugepage_info_init(void)
+{
+	if (hugepage_claim_privilege() < 0) {
+		RTE_LOG(ERR, EAL, "Cannot claim hugepage privilege\n");
+		return -1;
+	}
+
+	if (hugepage_info_init() < 0) {
+		RTE_LOG(ERR, EAL, "Cannot get hugepage information\n");
+		return -1;
+	}
+
+	return 0;
+}
diff --git a/lib/librte_eal/windows/meson.build b/lib/librte_eal/windows/meson.build
index adfc8b9b7..52978e9d7 100644
--- a/lib/librte_eal/windows/meson.build
+++ b/lib/librte_eal/windows/meson.build
@@ -6,6 +6,7 @@ subdir('include')
 sources += files(
 	'eal.c',
 	'eal_debug.c',
+	'eal_hugepages.c',
 	'eal_lcore.c',
 	'eal_log.c',
 	'eal_thread.c',
-- 
2.25.4