Added stubs for modifying "semaphore" priority, in order to facilitate

priority inheritance. Also fixed a few bugs. Many files were modified, as
the PI semaphores were are implementing replicate much of the original
Linux semaphore implementation with minor changes, often causing a cascade
of changes as functions were chased down and changed in several files.

2 files changed, 16 insertions, 1 deletions

diff --git a/include/linux/rt_param.h b/include/linux/rt_param.h
index c5c0452314..d79b100052 100644
--- a/include/linux/rt_param.h
+++ b/include/linux/rt_param.h
@@ -5,6 +5,8 @@
 #ifndef _LINUX_RT_PARAM_H_
 #define _LINUX_RT_PARAM_H_
 
+#include <linux/wait.h>
+
 typedef unsigned long jiffie_t;
 
 /* different types of clients */
@@ -115,7 +117,7 @@ memset(&(t)->rt_param,0, sizeof(struct task_rt_param))
         (t)->rt_param.times.exec_time))
 
 
-/* real-time comparisn macros */
+/* real-time comparison macros */
 #define earlier_deadline(a, b) (time_before(\
         (a)->rt_param.times.deadline,\
         (b)->rt_param.times.deadline))
@@ -123,4 +125,15 @@ memset(&(t)->rt_param,0, sizeof(struct task_rt_param))
         (a)->rt_param.times.release,\
         (b)->rt_param.times.release))
 
+/* definition of lowest semaphore priority */
+#define LOWEST_SEM_PRIO 200 /* TODO: change to meaningful prio value */
+
+/* struct for semaphore with priority inheritance */
+struct pi_semaphore {
+        atomic_t count;
+        int sleepers;
+        wait_queue_head_t wait;
+        jiffie_t sem_prio; /* priority of task holding the semaphore resource */
+};
+
 #endif
diff --git a/include/linux/wait.h b/include/linux/wait.h
index e820d00e13..c7e96b6b59 100644
--- a/include/linux/wait.h
+++ b/include/linux/wait.h
@@ -161,6 +161,8 @@ wait_queue_head_t *FASTCALL(bit_waitqueue(void *, int));
 #define wake_up_locked(x)               __wake_up_locked((x), TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE)
 #define wake_up_interruptible_sync(x)   __wake_up_sync((x),TASK_INTERRUPTIBLE, 1)
 
+#define pi_wake_up(x)                   __pi_wake_up(x, TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE, 1, NULL)
+
 #define __wait_event(wq, condition)                                     \
 do {                                                                    \
         DEFINE_WAIT(__wait);                                            \