sched: preempt-rt support

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

2 files changed, 49 insertions, 13 deletions

diff --git a/include/linux/hardirq.h b/include/linux/hardirq.h
index 1518625411a4..70b12547cfb2 100644
--- a/include/linux/hardirq.h
+++ b/include/linux/hardirq.h
@@ -96,19 +96,6 @@
 #define in_atomic()             ((preempt_count() & ~PREEMPT_ACTIVE) != 0)
 
 #ifdef CONFIG_PREEMPT
-# define PREEMPT_CHECK_OFFSET 1
-#else
-# define PREEMPT_CHECK_OFFSET 0
-#endif
-
-/*
- * Check whether we were atomic before we did preempt_disable():
- * (used by the scheduler)
- */
-#define in_atomic_preempt_off() \
-                ((preempt_count() & ~PREEMPT_ACTIVE) != PREEMPT_CHECK_OFFSET)
-
-#ifdef CONFIG_PREEMPT
 # define preemptible()  (preempt_count() == 0 && !irqs_disabled())
 # define IRQ_EXIT_OFFSET (HARDIRQ_OFFSET-1)
 #else
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 69faf651b10a..2e5be662deef 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -100,6 +100,17 @@ struct fs_struct;
 struct bts_context;
 struct perf_counter_context;
 
+#ifdef CONFIG_PREEMPT
+extern int kernel_preemption;
+#else
+# define kernel_preemption 0
+#endif
+#ifdef CONFIG_PREEMPT_VOLUNTARY
+extern int voluntary_preemption;
+#else
+# define voluntary_preemption 0
+#endif
+
 #ifdef CONFIG_PREEMPT_SOFTIRQS
 extern int softirq_preemption;
 #else
@@ -225,6 +236,28 @@ extern struct semaphore kernel_sem;
 #define set_task_state(tsk, state_value)                \
         set_mb((tsk)->state, (state_value))
 
+// #define PREEMPT_DIRECT
+
+#ifdef CONFIG_X86_LOCAL_APIC
+extern void nmi_show_all_regs(void);
+#else
+# define nmi_show_all_regs() do { } while (0)
+#endif
+
+#include <linux/smp.h>
+#include <linux/sem.h>
+#include <linux/signal.h>
+#include <linux/securebits.h>
+#include <linux/fs_struct.h>
+#include <linux/compiler.h>
+#include <linux/completion.h>
+#include <linux/pid.h>
+#include <linux/percpu.h>
+#include <linux/topology.h>
+#include <linux/seccomp.h>
+
+struct exec_domain;
+
 /*
  * set_current_state() includes a barrier so that the write of current->state
  * is correctly serialised wrt the caller's subsequent test of whether to
@@ -354,6 +387,11 @@ extern signed long schedule_timeout_uninterruptible(signed long timeout);
 asmlinkage void __schedule(void);
 asmlinkage void schedule(void);
 extern int mutex_spin_on_owner(struct mutex *lock, struct thread_info *owner);
+/*
+ * This one can be called with interrupts disabled, only
+ * to be used by lowlevel arch code!
+ */
+asmlinkage void __sched __schedule(void);
 
 struct nsproxy;
 struct user_namespace;
@@ -1686,6 +1724,15 @@ extern struct pid *cad_pid;
 extern void free_task(struct task_struct *tsk);
 #define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
 
+#ifdef CONFIG_PREEMPT_RT
+extern void __put_task_struct_cb(struct rcu_head *rhp);
+
+static inline void put_task_struct(struct task_struct *t)
+{
+        if (atomic_dec_and_test(&t->usage))
+                call_rcu(&t->rcu, __put_task_struct_cb);
+}
+#else
 extern void __put_task_struct(struct task_struct *t);
 
 static inline void put_task_struct(struct task_struct *t)
@@ -1693,6 +1740,7 @@ static inline void put_task_struct(struct task_struct *t)
         if (atomic_dec_and_test(&t->usage))
                 __put_task_struct(t);
 }
+#endif
 
 extern cputime_t task_utime(struct task_struct *p);
 extern cputime_t task_stime(struct task_struct *p);
@@ -1910,6 +1958,7 @@ extern struct task_struct *curr_task(int cpu);
 extern void set_curr_task(int cpu, struct task_struct *p);
 
 void yield(void);
+void __yield(void);
 
 /*
  * The default (Linux) execution domain.