LITMUS^RT core: add next_became_invalid() callback

1 files changed, 8 insertions, 0 deletions

diff --git a/include/litmus/sched_plugin.h b/include/litmus/sched_plugin.h
index 1906a139e6e9..2021e817b243 100644
--- a/include/litmus/sched_plugin.h
+++ b/include/litmus/sched_plugin.h
@@ -35,6 +35,11 @@ typedef void (*finish_switch_t)(struct task_struct *prev);
  * the scheduler is invoked again. */
 typedef bool (*should_wait_for_stack_t)(struct task_struct *next);
 
+/* After dropping the lock to facilitate a pull migration, the task
+ * state may have changed. In this case, the core notifies the plugin
+ * with this callback and then invokes the scheduler again. */
+typedef void (*next_became_invalid_t)(struct task_struct *next);
+
 /********************* task state changes ********************/
 
 /* Called to setup a new real-time task.
@@ -109,7 +114,10 @@ struct sched_plugin {
         /*      scheduler invocation    */
         schedule_t              schedule;
         finish_switch_t         finish_switch;
+
+        /* control over pull migrations */
         should_wait_for_stack_t should_wait_for_stack;
+        next_became_invalid_t next_became_invalid;
 
         /*      syscall backend         */
         complete_job_t          complete_job;