vold: Give logwrapper the ability to put jobs into the background sched group.

   Also set disk check/format execution to background.

Signed-off-by: San Mehat <san@google.com>
diff --git a/vold/logwrapper.c b/vold/logwrapper.c
index 2900f2e..46f6ed3 100644
--- a/vold/logwrapper.c
+++ b/vold/logwrapper.c
@@ -100,7 +100,7 @@
     }
 }
 
-int logwrap(int argc, char* argv[], pid_t *childPid)
+int logwrap(int argc, char* argv[], pid_t *childPid, int background)
 {
     pid_t pid;
 
@@ -138,6 +138,25 @@
         dup2(child_ptty, 2);
         close(child_ptty);
 
+        if (background) {
+            int fd = open("/dev/cpuctl/bg_non_interactive/tasks", O_WRONLY);
+      
+            if (fd >=0 ) {
+                char text[64];
+
+                sprintf(text, "%d", getpid());
+                if (write(fd, text, strlen(text)) < 0) {
+                    LOG(LOG_WARN, "logwrapper",
+                        "Unable to background process (%s)", strerror(errno));
+                    close(fd);
+                }
+                close(fd);
+            } else {
+                LOG(LOG_WARN, "logwrapper",
+                    "Unable to background process (%s)", strerror(errno));
+            }
+        }
+
         child(argc, argv);
     } else {
         return parent(argv[0], parent_ptty);