first changes to compile with LITMUS 20082008.0

2 files changed, 40 insertions, 13 deletions

diff --git a/src/syscalls.c b/src/syscalls.c
index 40f5f7f..1ad709b 100644
--- a/src/syscalls.c
+++ b/src/syscalls.c
@@ -1,4 +1,4 @@
-/* To get syscall() we need to define _GNU_SOURCE 
+/* To get syscall() we need to define _GNU_SOURCE
  * in modern glibc versions.
  */
 #define _GNU_SOURCE
@@ -87,8 +87,12 @@ int wait_for_job_release(unsigned int job_no)
         return syscall(__NR_wait_for_job_release, job_no);
 }
 
-int task_mode(int target_mode)
+int sched_setscheduler(pid_t pid, int policy, int* priority)
 {
-        return syscall(__NR_task_mode, target_mode);
+        return syscall(__NR_sched_setscheduler, pid, policy, priority);
 }
 
+int sched_getscheduler(pid_t pid)
+{
+        return syscall(__NR_sched_getscheduler, pid);
+}
diff --git a/src/task.c b/src/task.c
index 7cfa6ce..0036efb 100644
--- a/src/task.c
+++ b/src/task.c
@@ -1,30 +1,31 @@
 #include <stdlib.h>
 #include <stdio.h>
 #include <unistd.h>
+#include <errno.h>
 
 #include "litmus.h"
 #include "internal.h"
 
-static void tperrorx(char* msg) 
+static void tperrorx(char* msg)
 {
-        fprintf(stderr, 
+        fprintf(stderr,
                 "Task %d: %s: %m",
-                getpid(), msg);
+                gettid(), msg);
         exit(-1);
 }
 
 /* common launch routine */
-int __launch_rt_task(rt_fn_t rt_prog, void *rt_arg, rt_setup_fn_t setup, 
-                     void* setup_arg) 
+int __launch_rt_task(rt_fn_t rt_prog, void *rt_arg, rt_setup_fn_t setup,
+                     void* setup_arg)
 {
         int ret;
         int rt_task = fork();
 
         if (rt_task == 0) {
-                /* we are the real-time task 
+                /* we are the real-time task
                  * launch task and die when it is done
-                 */             
-                rt_task = getpid();             
+                 */
+                rt_task = gettid();
                 ret = setup(rt_task, setup_arg);
                 if (ret < 0)
                         tperrorx("could not setup task parameters");
@@ -38,14 +39,14 @@ int __launch_rt_task(rt_fn_t rt_prog, void *rt_arg, rt_setup_fn_t setup,
 }
 
 int __create_rt_task(rt_fn_t rt_prog, void *arg, int cpu, int wcet, int period,
-                     task_class_t class) 
+                     task_class_t class)
 {
         struct rt_task params;
         params.cpu = cpu;
         params.period = period;
         params.exec_cost = wcet;
         params.cls = class;
-        return __launch_rt_task(rt_prog, arg, 
+        return __launch_rt_task(rt_prog, arg,
                                 (rt_setup_fn_t) set_rt_task_param, &params);
 }
 
@@ -53,3 +54,25 @@ int create_rt_task(rt_fn_t rt_prog, void *arg, int cpu, int wcet, int period) {
         return __create_rt_task(rt_prog, arg, cpu, wcet, period, RT_CLASS_HARD);
 }
 
+
+#define SCHED_NORMAL 0
+#define SCHED_LITMUS 6
+
+int task_mode(int mode)
+{
+        int prio   = 0;
+        int me     = gettid();
+        int policy = sched_getscheduler(gettid());
+        int old_mode = policy == SCHED_LITMUS ? LITMUS_RT_TASK : BACKGROUND_TASK;
+
+        if (old_mode == LITMUS_RT_TASK && mode == BACKGROUND_TASK) {
+                /* transition to normal task */
+                return sched_setscheduler(me, SCHED_NORMAL, &prio);
+        } else if (old_mode == BACKGROUND_TASK && mode == LITMUS_RT_TASK) {
+                /* transition to RT task */
+                return sched_setscheduler(me, SCHED_LITMUS, &prio);
+        } else {
+                errno = -EINVAL;
+                return -1;
+        }
+}