1 files changed, 53 insertions, 4 deletions

diff --git a/include/linux/timer.h b/include/linux/timer.h
index a2d1eb6cb3f0..6abd9138beda 100644
--- a/include/linux/timer.h
+++ b/include/linux/timer.h
@@ -10,17 +10,23 @@
 struct tvec_base;
 
 struct timer_list {
+        /*
+         * All fields that change during normal runtime grouped to the
+         * same cacheline
+         */
         struct list_head entry;
         unsigned long expires;
+        struct tvec_base *base;
 
         void (*function)(unsigned long);
         unsigned long data;
 
-        struct tvec_base *base;
+        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;
@@ -42,12 +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__))     \
         }
@@ -94,6 +126,13 @@ void init_timer_deferrable_key(struct timer_list *timer,
                 setup_timer_on_stack_key((timer), #timer, &__key,       \
                                          (fn), (data));                 \
         } while (0)
+#define setup_deferrable_timer_on_stack(timer, fn, data)                \
+        do {                                                            \
+                static struct lock_class_key __key;                     \
+                setup_deferrable_timer_on_stack_key((timer), #timer,    \
+                                                    &__key, (fn),       \
+                                                    (data));            \
+        } while (0)
 #else
 #define init_timer(timer)\
         init_timer_key((timer), NULL, NULL)
@@ -105,6 +144,8 @@ void init_timer_deferrable_key(struct timer_list *timer,
         setup_timer_key((timer), NULL, NULL, (fn), (data))
 #define setup_timer_on_stack(timer, fn, data)\
         setup_timer_on_stack_key((timer), NULL, NULL, (fn), (data))
+#define setup_deferrable_timer_on_stack(timer, fn, data)\
+        setup_deferrable_timer_on_stack_key((timer), NULL, NULL, (fn), (data))
 #endif
 
 #ifdef CONFIG_DEBUG_OBJECTS_TIMERS
@@ -144,6 +185,12 @@ static inline void setup_timer_on_stack_key(struct timer_list *timer,
         init_timer_on_stack_key(timer, name, key);
 }
 
+extern void setup_deferrable_timer_on_stack_key(struct timer_list *timer,
+                                                const char *name,
+                                                struct lock_class_key *key,
+                                                void (*function)(unsigned long),
+                                                unsigned long data);
+
 /**
  * timer_pending - is a timer pending?
  * @timer: the timer in question
@@ -165,6 +212,8 @@ extern int mod_timer(struct timer_list *timer, unsigned long expires);
 extern int mod_timer_pending(struct timer_list *timer, unsigned long expires);
 extern int mod_timer_pinned(struct timer_list *timer, unsigned long expires);
 
+extern void set_timer_slack(struct timer_list *time, int slack_hz);
+
 #define TIMER_NOT_PINNED        0
 #define TIMER_PINNED            1
 /*
@@ -225,11 +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