LITMUS: let plugins declare their willingness to allow synchronization

- don't let SRP be active under GSN-EDF
- later, don't let FMLP be active under PFAIR, either

3 files changed, 15 insertions, 0 deletions

diff --git a/include/litmus/sched_plugin.h b/include/litmus/sched_plugin.h
index 421c54f517..872a7cbff3 100644
--- a/include/litmus/sched_plugin.h
+++ b/include/litmus/sched_plugin.h
@@ -85,6 +85,8 @@ struct sched_plugin {
         struct list_head        list;
         /*      basic info              */
         char                    *plugin_name;
+        unsigned int            srp_active;
+        unsigned int            fmlp_active;
 
         /*      scheduler invocation    */
         scheduler_tick_t        tick;
@@ -115,4 +117,14 @@ int register_sched_plugin(struct sched_plugin* plugin);
 struct sched_plugin* find_sched_plugin(const char* name);
 int print_sched_plugins(char* buf, int max);
 
+static inline int srp_active(void)
+{
+        return litmus->srp_active;
+}
+
+static inline int fmlp_active(void)
+{
+        return litmus->fmlp_active;
+}
+
 #endif
diff --git a/litmus/sched_gsn_edf.c b/litmus/sched_gsn_edf.c
index 6d9539cc0b..5dcc250aa6 100644
--- a/litmus/sched_gsn_edf.c
+++ b/litmus/sched_gsn_edf.c
@@ -695,6 +695,7 @@ static long gsnedf_admit_task(struct task_struct* tsk)
 /*      Plugin object   */
 static struct sched_plugin gsn_edf_plugin __cacheline_aligned_in_smp = {
         .plugin_name            = "GSN-EDF",
+        .fmlp_active            = 1,
         .finish_switch          = gsnedf_finish_switch,
         .tick                   = gsnedf_tick,
         .task_new               = gsnedf_task_new,
diff --git a/litmus/sched_psn_edf.c b/litmus/sched_psn_edf.c
index 7fb61ff75a..d4d01789b0 100644
--- a/litmus/sched_psn_edf.c
+++ b/litmus/sched_psn_edf.c
@@ -436,6 +436,8 @@ static long psnedf_admit_task(struct task_struct* tsk)
 /*      Plugin object   */
 static struct sched_plugin psn_edf_plugin __cacheline_aligned_in_smp = {
         .plugin_name            = "PSN-EDF",
+        .fmlp_active            = 1,
+        .srp_active             = 1,
         .tick                   = psnedf_tick,
         .task_new               = psnedf_task_new,
         .complete_job           = complete_job,