Added new class Msr.

src/hw/msr/Msr_linux.cpp

@@ -0,0 +1,86 @@
+/* XMRig
+ * Copyright (c) 2018-2021 SChernykh   <https://github.com/SChernykh>
+ * Copyright (c) 2016-2021 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 "hw/msr/Msr.h"
+#include "3rdparty/fmt/core.h"
+#include "base/io/log/Log.h"
+
+
+#include <array>
+#include <cctype>
+#include <cinttypes>
+#include <cstdio>
+#include <dirent.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+#include <signal.h>
+#include <ucontext.h>
+
+
+namespace xmrig {
+
+
+class MsrPrivate
+{
+public:
+    bool available = true;
+};
+
+
+} // namespace xmrig
+
+
+xmrig::Msr::Msr() : d_ptr(new MsrPrivate())
+{
+    if (system("/sbin/modprobe msr allow_writes=on > /dev/null 2>&1") != 0) {
+        LOG_WARN("%s " YELLOW_BOLD("msr kernel module is not available"), Msr::tag());
+
+        d_ptr->available = false;
+    }
+}
+
+
+xmrig::Msr::~Msr()
+{
+    delete d_ptr;
+}
+
+
+bool xmrig::Msr::isAvailable() const
+{
+    return d_ptr->available;
+}
+
+
+bool xmrig::Msr::rdmsr(uint32_t reg, int32_t cpu, uint64_t &value) const
+{
+    const auto name = fmt::format("/dev/cpu/{}/msr", cpu < 0 ? 0 : cpu);
+    const int fd    = open(name.c_str(), O_RDONLY);
+
+    if (fd < 0) {
+        return false;
+    }
+
+    const bool success = pread(fd, &value, sizeof value, reg) == sizeof value;
+    close(fd);
+
+    return success;
+}