Merge branches 'doc.2014.02.24a', 'fixes.2014.02.26a' and 'rt.2014.02.17b' into HEAD

[firefly-linux-kernel-4.4.55.git] / include / linux / rcupdate.h

diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h
index 72bf3a01a4ee67ac8908212c3de3897d383a2161..cda2583d67e93ee199bca3c16877bdc114165533 100644 (file)
--- a/include/linux/rcupdate.h
+++ b/include/linux/rcupdate.h
@@ -12,8 +12,8 @@
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ * along with this program; if not, you can access it online at
+ * http://www.gnu.org/licenses/gpl-2.0.html.
  *
  * Copyright IBM Corporation, 2001
  *
@@ -44,7 +44,9 @@
 #include <linux/debugobjects.h>
 #include <linux/bug.h>
 #include <linux/compiler.h>
+#include <asm/barrier.h>
 
+extern int rcu_expedited; /* for sysctl */
 #ifdef CONFIG_RCU_TORTURE_TEST
 extern int rcutorture_runnable; /* for sysctl */
 #endif /* #ifdef CONFIG_RCU_TORTURE_TEST */
@@ -479,11 +481,9 @@ static inline void rcu_preempt_sleep_check(void)
        do {                                                            \
                rcu_preempt_sleep_check();                              \
                rcu_lockdep_assert(!lock_is_held(&rcu_bh_lock_map),     \
-                                  "Illegal context switch in RCU-bh"   \
-                                  " read-side critical section");      \
+                                  "Illegal context switch in RCU-bh read-side critical section"); \
                rcu_lockdep_assert(!lock_is_held(&rcu_sched_lock_map),  \
-                                  "Illegal context switch in RCU-sched"\
-                                  " read-side critical section");      \
+                                  "Illegal context switch in RCU-sched read-side critical section"); \
        } while (0)
 
 #else /* #ifdef CONFIG_PROVE_RCU */
@@ -510,43 +510,40 @@ static inline void rcu_preempt_sleep_check(void)
 #endif /* #else #ifdef __CHECKER__ */
 
 #define __rcu_access_pointer(p, space) \
-       ({ \
-               typeof(*p) *_________p1 = (typeof(*p)*__force )ACCESS_ONCE(p); \
-               rcu_dereference_sparse(p, space); \
-               ((typeof(*p) __force __kernel *)(_________p1)); \
-       })
+({ \
+       typeof(*p) *_________p1 = (typeof(*p) *__force)ACCESS_ONCE(p); \
+       rcu_dereference_sparse(p, space); \
+       ((typeof(*p) __force __kernel *)(_________p1)); \
+})
 #define __rcu_dereference_check(p, c, space) \
-       ({ \
-               typeof(*p) *_________p1 = (typeof(*p)*__force )ACCESS_ONCE(p); \
-               rcu_lockdep_assert(c, "suspicious rcu_dereference_check()" \
-                                     " usage"); \
-               rcu_dereference_sparse(p, space); \
-               smp_read_barrier_depends(); \
-               ((typeof(*p) __force __kernel *)(_________p1)); \
-       })
+({ \
+       typeof(*p) *_________p1 = (typeof(*p) *__force)ACCESS_ONCE(p); \
+       rcu_lockdep_assert(c, "suspicious rcu_dereference_check() usage"); \
+       rcu_dereference_sparse(p, space); \
+       smp_read_barrier_depends(); /* Dependency order vs. p above. */ \
+       ((typeof(*p) __force __kernel *)(_________p1)); \
+})
 #define __rcu_dereference_protected(p, c, space) \
-       ({ \
-               rcu_lockdep_assert(c, "suspicious rcu_dereference_protected()" \
-                                     " usage"); \
-               rcu_dereference_sparse(p, space); \
-               ((typeof(*p) __force __kernel *)(p)); \
-       })
+({ \
+       rcu_lockdep_assert(c, "suspicious rcu_dereference_protected() usage"); \
+       rcu_dereference_sparse(p, space); \
+       ((typeof(*p) __force __kernel *)(p)); \
+})
 
 #define __rcu_access_index(p, space) \
-       ({ \
-               typeof(p) _________p1 = ACCESS_ONCE(p); \
-               rcu_dereference_sparse(p, space); \
-               (_________p1); \
-       })
+({ \
+       typeof(p) _________p1 = ACCESS_ONCE(p); \
+       rcu_dereference_sparse(p, space); \
+       (_________p1); \
+})
 #define __rcu_dereference_index_check(p, c) \
-       ({ \
-               typeof(p) _________p1 = ACCESS_ONCE(p); \
-               rcu_lockdep_assert(c, \
-                                  "suspicious rcu_dereference_index_check()" \
-                                  " usage"); \
-               smp_read_barrier_depends(); \
-               (_________p1); \
-       })
+({ \
+       typeof(p) _________p1 = ACCESS_ONCE(p); \
+       rcu_lockdep_assert(c, \
+                          "suspicious rcu_dereference_index_check() usage"); \
+       smp_read_barrier_depends(); /* Dependency order vs. p above. */ \
+       (_________p1); \
+})
 
 /**
  * RCU_INITIALIZER() - statically initialize an RCU-protected global variable
@@ -585,12 +582,7 @@ static inline void rcu_preempt_sleep_check(void)
  * please be careful when making changes to rcu_assign_pointer() and the
  * other macros that it invokes.
  */
-#define rcu_assign_pointer(p, v) \
-       do { \
-               smp_wmb(); \
-               ACCESS_ONCE(p) = RCU_INITIALIZER(v); \
-       } while (0)
-
+#define rcu_assign_pointer(p, v) smp_store_release(&p, RCU_INITIALIZER(v))
 
 /**
  * rcu_access_pointer() - fetch RCU pointer with no dereferencing
@@ -1015,11 +1007,21 @@ static inline notrace void rcu_read_unlock_sched_notrace(void)
 #define kfree_rcu(ptr, rcu_head)                                       \
        __kfree_rcu(&((ptr)->rcu_head), offsetof(typeof(*(ptr)), rcu_head))
 
-#ifdef CONFIG_RCU_NOCB_CPU
+#if defined(CONFIG_TINY_RCU) || defined(CONFIG_RCU_NOCB_CPU_ALL)
+static inline int rcu_needs_cpu(int cpu, unsigned long *delta_jiffies)
+{
+       *delta_jiffies = ULONG_MAX;
+       return 0;
+}
+#endif /* #if defined(CONFIG_TINY_RCU) || defined(CONFIG_RCU_NOCB_CPU_ALL) */
+
+#if defined(CONFIG_RCU_NOCB_CPU_ALL)
+static inline bool rcu_is_nocb_cpu(int cpu) { return true; }
+#elif defined(CONFIG_RCU_NOCB_CPU)
 bool rcu_is_nocb_cpu(int cpu);
 #else
 static inline bool rcu_is_nocb_cpu(int cpu) { return false; }
-#endif /* #else #ifdef CONFIG_RCU_NOCB_CPU */
+#endif
 
 
 /* Only for use by adaptive-ticks code. */