[process] Make it safe to call process_add() multiple times

[people/peper/gpxe.git] / src / core / process.c

diff --git a/src/core/process.c b/src/core/process.c
index 6dacd66..9c13e02 100644 (file)
--- a/src/core/process.c
+++ b/src/core/process.c
@@ -37,11 +37,18 @@ static LIST_HEAD ( run_queue );
  * Add process to process list
  *
  * @v process          Process
  * Add process to process list
  *
  * @v process          Process

+ *
+ * It is safe to call process_add() multiple times; further calls will
+ * have no effect.

  */
 void process_add ( struct process *process ) {
  */
 void process_add ( struct process *process ) {

-       DBGC ( process, "PROCESS %p starting\n", process );
-       ref_get ( process->refcnt );
-       list_add_tail ( &process->list, &run_queue );
+       if ( list_empty ( &process->list ) ) {
+               DBGC ( process, "PROCESS %p starting\n", process );
+               ref_get ( process->refcnt );
+               list_add_tail ( &process->list, &run_queue );
+       } else {
+               DBGC ( process, "PROCESS %p already started\n", process );
+       }

 }
 
 /**
 }
 
 /**