core/locking changes for v3.12

GIT PULL Ingo Molnar 1 participant 1 message Sep 3, 2013

Subsystems (2)

Locking primitives Hung task detector

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Ingo Molnar

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2013-09-03 12:16 UTC #0 lore raw

Linus,

Please pull the latest core-locking-for-linus git tree from:

git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git core-locking-for-linus

HEAD: 15e71911fcc655508e02f767a3d9b8b138051d2b generic-ipi/locking: Fix misleading smp_call_function_any() description

Main changes:

- another mutex optimization, from Davidlohr Bueso

- improved lglock lockdep tracking, from Michel Lespinasse

- [ assorted smaller updates, improvements, cleanups. ]

Thanks,

Ingo

------------------>
Davidlohr Bueso (2):
mutex: Do not unnecessarily deal with waiters
mutex: Avoid label warning when !CONFIG_MUTEX_SPIN_ON_OWNER

Michel Lespinasse (2):
lockdep: Introduce lock_acquire_exclusive()/shared() helper macros
lglock: Update lockdep annotations to report recursive local locks

Oleg Nesterov (1):
hung_task debugging: Print more info when reporting the problem

Peter Zijlstra (1):
mutex: Fix/document access-once assumption in mutex_can_spin_on_owner()

Xie XiuQi (1):
generic-ipi/locking: Fix misleading smp_call_function_any() description

 include/linux/lockdep.h | 92 +++++++++++++------------------------------------
 kernel/hung_task.c      | 13 ++++---
 kernel/lglock.c         | 12 +++----
 kernel/mutex.c          | 43 +++++++++++------------
 kernel/smp.c            |  2 --
 5 files changed, 58 insertions(+), 104 deletions(-)

include/linux/lockdep.h +23 ~~-69~~

index f1e877b..cfc2f11 100644
@@ -365,7 +365,7 @@ extern void lockdep_trace_alloc(gfp_t mask);
 
 #define lockdep_recursing(tsk)	((tsk)->lockdep_recursion)
 
-#else /* !LOCKDEP */
+#else /* !CONFIG_LOCKDEP */
 
 static inline void lockdep_off(void)
 {

@@ -479,82 +479,36 @@ static inline void print_irqtrace_events(struct task_struct *curr)
  * on the per lock-class debug mode:
  */
 
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
-# ifdef CONFIG_PROVE_LOCKING
-#  define spin_acquire(l, s, t, i)		lock_acquire(l, s, t, 0, 2, NULL, i)
-#  define spin_acquire_nest(l, s, t, n, i)	lock_acquire(l, s, t, 0, 2, n, i)
-# else
-#  define spin_acquire(l, s, t, i)		lock_acquire(l, s, t, 0, 1, NULL, i)
-#  define spin_acquire_nest(l, s, t, n, i)	lock_acquire(l, s, t, 0, 1, NULL, i)
-# endif
-# define spin_release(l, n, i)			lock_release(l, n, i)
+#ifdef CONFIG_PROVE_LOCKING
+ #define lock_acquire_exclusive(l, s, t, n, i)		lock_acquire(l, s, t, 0, 2, n, i)
+ #define lock_acquire_shared(l, s, t, n, i)		lock_acquire(l, s, t, 1, 2, n, i)
+ #define lock_acquire_shared_recursive(l, s, t, n, i)	lock_acquire(l, s, t, 2, 2, n, i)
 #else
-# define spin_acquire(l, s, t, i)		do { } while (0)
-# define spin_release(l, n, i)			do { } while (0)
+ #define lock_acquire_exclusive(l, s, t, n, i)		lock_acquire(l, s, t, 0, 1, n, i)
+ #define lock_acquire_shared(l, s, t, n, i)		lock_acquire(l, s, t, 1, 1, n, i)
+ #define lock_acquire_shared_recursive(l, s, t, n, i)	lock_acquire(l, s, t, 2, 1, n, i)
 #endif
 
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
-# ifdef CONFIG_PROVE_LOCKING
-#  define rwlock_acquire(l, s, t, i)		lock_acquire(l, s, t, 0, 2, NULL, i)
-#  define rwlock_acquire_read(l, s, t, i)	lock_acquire(l, s, t, 2, 2, NULL, i)
-# else
-#  define rwlock_acquire(l, s, t, i)		lock_acquire(l, s, t, 0, 1, NULL, i)
-#  define rwlock_acquire_read(l, s, t, i)	lock_acquire(l, s, t, 2, 1, NULL, i)
-# endif
-# define rwlock_release(l, n, i)		lock_release(l, n, i)
-#else
-# define rwlock_acquire(l, s, t, i)		do { } while (0)
-# define rwlock_acquire_read(l, s, t, i)	do { } while (0)
-# define rwlock_release(l, n, i)		do { } while (0)
-#endif
+#define spin_acquire(l, s, t, i)		lock_acquire_exclusive(l, s, t, NULL, i)
+#define spin_acquire_nest(l, s, t, n, i)	lock_acquire_exclusive(l, s, t, n, i)
+#define spin_release(l, n, i)			lock_release(l, n, i)
 
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
-# ifdef CONFIG_PROVE_LOCKING
-#  define mutex_acquire(l, s, t, i)		lock_acquire(l, s, t, 0, 2, NULL, i)
-#  define mutex_acquire_nest(l, s, t, n, i)	lock_acquire(l, s, t, 0, 2, n, i)
-# else
-#  define mutex_acquire(l, s, t, i)		lock_acquire(l, s, t, 0, 1, NULL, i)
-#  define mutex_acquire_nest(l, s, t, n, i)	lock_acquire(l, s, t, 0, 1, n, i)
-# endif
-# define mutex_release(l, n, i)			lock_release(l, n, i)
-#else
-# define mutex_acquire(l, s, t, i)		do { } while (0)
-# define mutex_acquire_nest(l, s, t, n, i)	do { } while (0)
-# define mutex_release(l, n, i)			do { } while (0)
-#endif
+#define rwlock_acquire(l, s, t, i)		lock_acquire_exclusive(l, s, t, NULL, i)
+#define rwlock_acquire_read(l, s, t, i)		lock_acquire_shared_recursive(l, s, t, NULL, i)
+#define rwlock_release(l, n, i)			lock_release(l, n, i)
 
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
-# ifdef CONFIG_PROVE_LOCKING
-#  define rwsem_acquire(l, s, t, i)		lock_acquire(l, s, t, 0, 2, NULL, i)
-#  define rwsem_acquire_nest(l, s, t, n, i)	lock_acquire(l, s, t, 0, 2, n, i)
-#  define rwsem_acquire_read(l, s, t, i)	lock_acquire(l, s, t, 1, 2, NULL, i)
-# else
-#  define rwsem_acquire(l, s, t, i)		lock_acquire(l, s, t, 0, 1, NULL, i)
-#  define rwsem_acquire_nest(l, s, t, n, i)	lock_acquire(l, s, t, 0, 1, n, i)
-#  define rwsem_acquire_read(l, s, t, i)	lock_acquire(l, s, t, 1, 1, NULL, i)
-# endif
+#define mutex_acquire(l, s, t, i)		lock_acquire_exclusive(l, s, t, NULL, i)
+#define mutex_acquire_nest(l, s, t, n, i)	lock_acquire_exclusive(l, s, t, n, i)
+#define mutex_release(l, n, i)			lock_release(l, n, i)
+
+#define rwsem_acquire(l, s, t, i)		lock_acquire_exclusive(l, s, t, NULL, i)
+#define rwsem_acquire_nest(l, s, t, n, i)	lock_acquire_exclusive(l, s, t, n, i)
+#define rwsem_acquire_read(l, s, t, i)		lock_acquire_shared(l, s, t, NULL, i)
 # define rwsem_release(l, n, i)			lock_release(l, n, i)
-#else
-# define rwsem_acquire(l, s, t, i)		do { } while (0)
-# define rwsem_acquire_nest(l, s, t, n, i)	do { } while (0)
-# define rwsem_acquire_read(l, s, t, i)		do { } while (0)
-# define rwsem_release(l, n, i)			do { } while (0)
-#endif
 
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
-# ifdef CONFIG_PROVE_LOCKING
-#  define lock_map_acquire(l)		lock_acquire(l, 0, 0, 0, 2, NULL, _THIS_IP_)
-#  define lock_map_acquire_read(l)	lock_acquire(l, 0, 0, 2, 2, NULL, _THIS_IP_)
-# else
-#  define lock_map_acquire(l)		lock_acquire(l, 0, 0, 0, 1, NULL, _THIS_IP_)
-#  define lock_map_acquire_read(l)	lock_acquire(l, 0, 0, 2, 1, NULL, _THIS_IP_)
-# endif
+#define lock_map_acquire(l)			lock_acquire_exclusive(l, 0, 0, NULL, _THIS_IP_)
+#define lock_map_acquire_read(l)		lock_acquire_shared_recursive(l, 0, 0, NULL, _THIS_IP_)
 # define lock_map_release(l)			lock_release(l, 1, _THIS_IP_)
-#else
-# define lock_map_acquire(l)			do { } while (0)
-# define lock_map_acquire_read(l)		do { } while (0)
-# define lock_map_release(l)			do { } while (0)
-#endif
 
 #ifdef CONFIG_PROVE_LOCKING
 # define might_lock(lock) 						\

kernel/hung_task.c +9 -4

index 6df6149..3e97fb1 100644
@@ -15,6 +15,7 @@
 #include <linux/lockdep.h>
 #include <linux/export.h>
 #include <linux/sysctl.h>
+#include <linux/utsname.h>
 
 /*
  * The number of tasks checked:

@@ -99,10 +100,14 @@ static void check_hung_task(struct task_struct *t, unsigned long timeout)
 	 * Ok, the task did not get scheduled for more than 2 minutes,
 	 * complain:
 	 */
-	printk(KERN_ERR "INFO: task %s:%d blocked for more than "
-			"%ld seconds.\n", t->comm, t->pid, timeout);
-	printk(KERN_ERR "\"echo 0 > /proc/sys/kernel/hung_task_timeout_secs\""
-			" disables this message.\n");
+	pr_err("INFO: task %s:%d blocked for more than %ld seconds.\n",
+		t->comm, t->pid, timeout);
+	pr_err("      %s %s %.*s\n",
+		print_tainted(), init_utsname()->release,
+		(int)strcspn(init_utsname()->version, " "),
+		init_utsname()->version);
+	pr_err("\"echo 0 > /proc/sys/kernel/hung_task_timeout_secs\""
+		" disables this message.\n");
 	sched_show_task(t);
 	debug_show_held_locks(t);

kernel/lglock.c +6 -6

index 6535a66..86ae2ae 100644
@@ -21,7 +21,7 @@ void lg_local_lock(struct lglock *lg)
 	arch_spinlock_t *lock;
 
 	preempt_disable();
-	rwlock_acquire_read(&lg->lock_dep_map, 0, 0, _RET_IP_);
+	lock_acquire_shared(&lg->lock_dep_map, 0, 0, NULL, _RET_IP_);
 	lock = this_cpu_ptr(lg->lock);
 	arch_spin_lock(lock);
 }

@@ -31,7 +31,7 @@ void lg_local_unlock(struct lglock *lg)
 {
 	arch_spinlock_t *lock;
 
-	rwlock_release(&lg->lock_dep_map, 1, _RET_IP_);
+	lock_release(&lg->lock_dep_map, 1, _RET_IP_);
 	lock = this_cpu_ptr(lg->lock);
 	arch_spin_unlock(lock);
 	preempt_enable();

@@ -43,7 +43,7 @@ void lg_local_lock_cpu(struct lglock *lg, int cpu)
 	arch_spinlock_t *lock;
 
 	preempt_disable();
-	rwlock_acquire_read(&lg->lock_dep_map, 0, 0, _RET_IP_);
+	lock_acquire_shared(&lg->lock_dep_map, 0, 0, NULL, _RET_IP_);
 	lock = per_cpu_ptr(lg->lock, cpu);
 	arch_spin_lock(lock);
 }

@@ -53,7 +53,7 @@ void lg_local_unlock_cpu(struct lglock *lg, int cpu)
 {
 	arch_spinlock_t *lock;
 
-	rwlock_release(&lg->lock_dep_map, 1, _RET_IP_);
+	lock_release(&lg->lock_dep_map, 1, _RET_IP_);
 	lock = per_cpu_ptr(lg->lock, cpu);
 	arch_spin_unlock(lock);
 	preempt_enable();

@@ -65,7 +65,7 @@ void lg_global_lock(struct lglock *lg)
 	int i;
 
 	preempt_disable();
-	rwlock_acquire(&lg->lock_dep_map, 0, 0, _RET_IP_);
+	lock_acquire_exclusive(&lg->lock_dep_map, 0, 0, NULL, _RET_IP_);
 	for_each_possible_cpu(i) {
 		arch_spinlock_t *lock;
 		lock = per_cpu_ptr(lg->lock, i);

@@ -78,7 +78,7 @@ void lg_global_unlock(struct lglock *lg)
 {
 	int i;
 
-	rwlock_release(&lg->lock_dep_map, 1, _RET_IP_);
+	lock_release(&lg->lock_dep_map, 1, _RET_IP_);
 	for_each_possible_cpu(i) {
 		arch_spinlock_t *lock;
 		lock = per_cpu_ptr(lg->lock, i);

kernel/mutex.c +20 ~~-23~~

113 lines not on this page · raw message

kernel/smp.c +0 -2

index fe9f773..b1c9034 100644
@@ -278,8 +278,6 @@ EXPORT_SYMBOL(smp_call_function_single);
  * @wait: If true, wait until function has completed.
  *
  * Returns 0 on success, else a negative status code (if no cpus were online).
- * Note that @wait will be implicitly turned on in case of allocation failures,
- * since we fall back to on-stack allocation.
  *
  * Selection preference:
  *	1) current cpu if in @mask