Memory allocation refactoring.

src/crypto/common/LinuxMemory.cpp

@@ -0,0 +1,103 @@
+/* XMRig
+ * Copyright 2010      Jeff Garzik <jgarzik@pobox.com>
+ * Copyright 2012-2014 pooler      <pooler@litecoinpool.org>
+ * Copyright 2014      Lucas Jones <https://github.com/lucasjones>
+ * Copyright 2014-2016 Wolf9466    <https://github.com/OhGodAPet>
+ * Copyright 2016      Jay D Dee   <jayddee246@gmail.com>
+ * Copyright 2017-2018 XMR-Stak    <https://github.com/fireice-uk>, <https://github.com/psychocrypt>
+ * Copyright 2018-2019 SChernykh   <https://github.com/SChernykh>
+ * Copyright 2016-2019 XMRig       <https://github.com/xmrig>, <support@xmrig.com>
+ *
+ *   This program is free software: you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation, either version 3 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program 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 for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+
+//#include <iostream>
+
+#include "crypto/common/LinuxMemory.h"
+#include "base/io/log/Log.h"
+#include "crypto/common/VirtualMemory.h"
+#include "backend/cpu/Cpu.h"
+
+
+#include <algorithm>
+#include <fstream>
+#include <string>
+#include <mutex>
+
+
+namespace xmrig {
+
+
+static std::mutex mutex;
+constexpr size_t twoMiB = 2U * 1024U * 1024U;
+constexpr size_t oneGiB = 1024U * 1024U * 1024U;
+
+
+static inline std::string sysfs_path(uint32_t node, bool oneGbPages, bool nr)
+{
+    return "/sys/devices/system/node/node" + std::to_string(node) + "/hugepages/hugepages-" + (oneGbPages ? "1048576" : "2048") + "kB/" + (nr ? "nr" : "free") + "_hugepages";
+}
+
+
+static inline bool write_nr_hugepages(uint32_t node, bool oneGbPages, uint64_t count)    { return LinuxMemory::write(sysfs_path(node, oneGbPages, true).c_str(), count); }
+static inline int64_t free_hugepages(uint32_t node, bool oneGbPages)                     { return LinuxMemory::read(sysfs_path(node, oneGbPages, false).c_str()); }
+static inline int64_t nr_hugepages(uint32_t node, bool oneGbPages)                       { return LinuxMemory::read(sysfs_path(node, oneGbPages, true).c_str()); }
+
+
+} // namespace xmrig
+
+
+bool xmrig::LinuxMemory::reserve(size_t size, uint32_t node, bool oneGbPages)
+{
+    std::lock_guard<std::mutex> lock(mutex);
+
+    const size_t pageSize = oneGbPages ? oneGiB : twoMiB;
+    const size_t required = VirtualMemory::align(size, pageSize) / pageSize;
+
+    const auto available = free_hugepages(node, oneGbPages);
+    if (available < 0 || static_cast<size_t>(available) >= required) {
+        return false;
+    }
+
+    return write_nr_hugepages(node, oneGbPages, std::max<size_t>(nr_hugepages(node, oneGbPages), 0) + (required - available));
+}
+
+
+bool xmrig::LinuxMemory::write(const char *path, uint64_t value)
+{
+    std::ofstream file(path, std::ios::out | std::ios::binary | std::ios::trunc);
+    if (!file.is_open()) {
+        return false;
+    }
+
+    file << value;
+    file.flush();
+
+    return true;
+}
+
+
+int64_t xmrig::LinuxMemory::read(const char *path)
+{
+    std::ifstream file(path);
+    if (!file.is_open()) {
+        return -1;
+    }
+
+    uint64_t value = 0;
+    file >> value;
+
+    return value;
+}