kvm: Use lscpu to get cpu max speed (#5506)

* kvm: Use lscpu to get cpu max speed

* Fix str conversion

* Reorder

* Refactor

* Apply suggestions from code review

Co-authored-by: Daniel Augusto Veronezi Salvador <38945620+GutoVeronezi@users.noreply.github.com>

* Updated the calling method name getCpuSpeedFromCommandLscpu

* Make it more readable

Co-authored-by: Daniel Augusto Veronezi Salvador <38945620+GutoVeronezi@users.noreply.github.com>
Co-authored-by: sureshanaparti <12028987+sureshanaparti@users.noreply.github.com>

Author: 3 people

plugins/hypervisors/kvm/src/main/java/org/apache/cloudstack/utils/linux/KVMHostInfo.java

@@ -18,6 +18,8 @@
 
 import com.cloud.hypervisor.kvm.resource.LibvirtCapXMLParser;
 import com.cloud.hypervisor.kvm.resource.LibvirtConnection;
+import com.cloud.utils.script.Script;
+
 import org.apache.commons.io.IOUtils;
 import org.apache.log4j.Logger;
 import org.libvirt.Connect;
@@ -80,13 +82,45 @@ public List<String> getCapabilities() {
     }
 
     protected static long getCpuSpeed(final NodeInfo nodeInfo) {
+        long speed = 0L;
+        speed = getCpuSpeedFromCommandLscpu();
+        if(speed > 0L) {
+            return speed;
+        }
+
+        speed = getCpuSpeedFromFile();
+        if(speed > 0L) {
+            return speed;
+        }
+
+        LOGGER.info(String.format("Using the value [%s] provided by Libvirt.", nodeInfo.mhz));
+        speed = nodeInfo.mhz;
+        return speed;
+    }
+
+    private static long getCpuSpeedFromCommandLscpu() {
+        try {
+            LOGGER.info("Fetching CPU speed from command \"lscpu\".");
+            String command = "lscpu | grep -i 'Model name' | head -n 1 | egrep -o '[[:digit:]].[[:digit:]]+GHz' | sed 's/GHz//g'";
+            String result = Script.runSimpleBashScript(command);
+            long speed = (long) (Float.parseFloat(result) * 1000);
+            LOGGER.info(String.format("Command [%s] resulted in the value [%s] for CPU speed.", command, speed));
+            return speed;
+        } catch (NullPointerException | NumberFormatException e) {
+            LOGGER.error(String.format("Unable to retrieve the CPU speed from lscpu."), e);
+            return 0L;
+        }
+    }
+
+    private static long getCpuSpeedFromFile() {
+        LOGGER.info(String.format("Fetching CPU speed from file [%s].", cpuInfoMaxFreqFileName));
         try (Reader reader = new FileReader(cpuInfoMaxFreqFileName)) {
             Long cpuInfoMaxFreq = Long.parseLong(IOUtils.toString(reader).trim());
             LOGGER.info(String.format("Retrieved value [%s] from file [%s]. This corresponds to a CPU speed of [%s] MHz.", cpuInfoMaxFreq, cpuInfoMaxFreqFileName, cpuInfoMaxFreq / 1000));
             return cpuInfoMaxFreq / 1000;
         } catch (IOException | NumberFormatException e) {
-            LOGGER.error(String.format("Unable to retrieve the CPU speed from file [%s]. Using the value [%s] provided by the Libvirt.", cpuInfoMaxFreqFileName, nodeInfo.mhz), e);
-            return nodeInfo.mhz;
+            LOGGER.error(String.format("Unable to retrieve the CPU speed from file [%s]", cpuInfoMaxFreqFileName), e);
+            return 0L;
         }
     }