[REVIEW] FEA Support Multi-Instance GPUs

src/main/java/com/gpuopenanalytics/jenkins/remotedocker/config/NvidiaGpuDevicesConfigItem.java

@@ -26,12 +26,22 @@
 
 import com.gpuopenanalytics.jenkins.remotedocker.AbstractDockerLauncher;
 import hudson.Extension;
+import hudson.Launcher;
 import hudson.model.Descriptor;
 import hudson.util.ArgumentListBuilder;
 import org.apache.commons.lang.StringUtils;
 import org.jenkinsci.Symbol;
 import org.kohsuke.stapler.DataBoundConstructor;
 
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+import java.util.Arrays;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
 /**
  * Defines which GPU devices are visible in the container. Passes
  * <code>-e NVIDIA_VISIBLE_DEVICES=value</code>
@@ -69,7 +79,13 @@ public void addCreateArgs(AbstractDockerLauncher launcher,
                               ArgumentListBuilder args) {
         String value;
         if ("executor".equals(getValue())) {
-            value = launcher.getEnvironment().get("EXECUTOR_NUMBER");
+            String executorNum = launcher.getEnvironment().get("EXECUTOR_NUMBER");
+            String nvidiasmiOutput = executeWithOutput(launcher.getInner(), "nvidia-smi", "-L");
+            if (isMIG(nvidiasmiOutput)) {
+                value = getMIG(nvidiasmiOutput, executorNum);
+            } else {
+                value = executorNum;
+            }
         } else {
             value = getResolvedValue(launcher);
         }
@@ -99,4 +115,45 @@ public String getDisplayName() {
             return "NVIDIA Device Visibility";
         }
     }
+
+    private String executeWithOutput(Launcher launcher, String... args) {
+        try {
+            ByteArrayOutputStream baos = new ByteArrayOutputStream();
+            int status = launcher.launch()
+                    .cmds(args)
+                    .stdout(baos)
+                    .stderr(launcher.getListener().getLogger())
+                    .join();
+            if (status != 0) {
+                throw new RuntimeException(
+                        "Non-zero status " + status + ": " + Arrays
+                                .toString(args));
+            }
+            return baos.toString(StandardCharsets.UTF_8.name()).trim();
+        } catch (InterruptedException | IOException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    private boolean isMIG(String output) {
+        Pattern pattern = Pattern.compile("(MIG-GPU-[a-f0-9\\-\\/]+)");
+        Matcher m = pattern.matcher(output);
+
+        if (m.find()) {
+            return true;
+        }
+        return false;
+    }
+
+    private String getMIG(String output, String executor) {
+        int executorNum = Integer.parseInt(executor);
+        List<String> uuids = new ArrayList<String>();
+        Pattern pattern = Pattern.compile("(MIG-GPU-[a-f0-9\\-\\/]+)");
+        Matcher m = pattern.matcher(output);
+
+        while (m.find()) {
+            uuids.add(m.group());
+        }
+        return uuids.get(executorNum);
+    }
 }