Merge 'Linux v3.0' into Litmus

Some notes:
* Litmus^RT scheduling class is the topmost scheduling class
  (above stop_sched_class).
* scheduler_ipi() function (e.g., in smp_reschedule_interrupt())
  may increase IPI latencies.
* Added path into schedule() to quickly re-evaluate scheduling
  decision without becoming preemptive again. This used to be
  a standard path before the removal of BKL.

Conflicts:
	Makefile
	arch/arm/kernel/calls.S
	arch/arm/kernel/smp.c
	arch/x86/include/asm/unistd_32.h
	arch/x86/kernel/smp.c
	arch/x86/kernel/syscall_table_32.S
	include/linux/hrtimer.h
	kernel/printk.c
	kernel/sched.c
	kernel/sched_fair.c

1 files changed, 29 insertions, 3 deletions

diff --git a/include/linux/timer.h b/include/linux/timer.h
index 38cf093ef62c..6abd9138beda 100644
--- a/include/linux/timer.h
+++ b/include/linux/timer.h
@@ -24,9 +24,9 @@ struct timer_list {
         int slack;
 
 #ifdef CONFIG_TIMER_STATS
+        int start_pid;
         void *start_site;
         char start_comm[16];
-        int start_pid;
 #endif
 #ifdef CONFIG_LOCKDEP
         struct lockdep_map lockdep_map;
@@ -48,12 +48,38 @@ extern struct tvec_base boot_tvec_bases;
 #define __TIMER_LOCKDEP_MAP_INITIALIZER(_kn)
 #endif
 
+/*
+ * Note that all tvec_bases are 2 byte aligned and lower bit of
+ * base in timer_list is guaranteed to be zero. Use the LSB to
+ * indicate whether the timer is deferrable.
+ *
+ * A deferrable timer will work normally when the system is busy, but
+ * will not cause a CPU to come out of idle just to service it; instead,
+ * the timer will be serviced when the CPU eventually wakes up with a
+ * subsequent non-deferrable timer.
+ */
+#define TBASE_DEFERRABLE_FLAG           (0x1)
+
 #define TIMER_INITIALIZER(_function, _expires, _data) {         \
                 .entry = { .prev = TIMER_ENTRY_STATIC },        \
                 .function = (_function),                        \
                 .expires = (_expires),                          \
                 .data = (_data),                                \
                 .base = &boot_tvec_bases,                       \
+                .slack = -1,                                    \
+                __TIMER_LOCKDEP_MAP_INITIALIZER(                \
+                        __FILE__ ":" __stringify(__LINE__))     \
+        }
+
+#define TBASE_MAKE_DEFERRED(ptr) ((struct tvec_base *)          \
+                  ((unsigned char *)(ptr) + TBASE_DEFERRABLE_FLAG))
+
+#define TIMER_DEFERRED_INITIALIZER(_function, _expires, _data) {\
+                .entry = { .prev = TIMER_ENTRY_STATIC },        \
+                .function = (_function),                        \
+                .expires = (_expires),                          \
+                .data = (_data),                                \
+                .base = TBASE_MAKE_DEFERRED(&boot_tvec_bases),  \
                 __TIMER_LOCKDEP_MAP_INITIALIZER(                \
                         __FILE__ ":" __stringify(__LINE__))     \
         }
@@ -248,11 +274,11 @@ static inline void timer_stats_timer_clear_start_info(struct timer_list *timer)
 
 extern void add_timer(struct timer_list *timer);
 
+extern int try_to_del_timer_sync(struct timer_list *timer);
+
 #ifdef CONFIG_SMP
-  extern int try_to_del_timer_sync(struct timer_list *timer);
   extern int del_timer_sync(struct timer_list *timer);
 #else
-# define try_to_del_timer_sync(t)       del_timer(t)
 # define del_timer_sync(t)              del_timer(t)
 #endif