Merge branch 'sched/core-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing into sched/core

15 files changed, 46 insertions, 34 deletions

diff --git a/Documentation/DocBook/kernel-hacking.tmpl b/Documentation/DocBook/kernel-hacking.tmpl
index 7b3f49363413..07a9c48de5a2 100644
--- a/Documentation/DocBook/kernel-hacking.tmpl
+++ b/Documentation/DocBook/kernel-hacking.tmpl
@@ -409,7 +409,7 @@ cond_resched(); /* Will sleep */
 
   <para>
    You should always compile your kernel
-   <symbol>CONFIG_DEBUG_SPINLOCK_SLEEP</symbol> on, and it will warn
+   <symbol>CONFIG_DEBUG_ATOMIC_SLEEP</symbol> on, and it will warn
    you if you break these rules.  If you <emphasis>do</emphasis> break
    the rules, you will eventually lock up your box.
   </para>
diff --git a/Documentation/SubmitChecklist b/Documentation/SubmitChecklist
index da0382daa395..7b13be41c085 100644
--- a/Documentation/SubmitChecklist
+++ b/Documentation/SubmitChecklist
@@ -53,7 +53,7 @@ kernel patches.
 
 12: Has been tested with CONFIG_PREEMPT, CONFIG_DEBUG_PREEMPT,
     CONFIG_DEBUG_SLAB, CONFIG_DEBUG_PAGEALLOC, CONFIG_DEBUG_MUTEXES,
-    CONFIG_DEBUG_SPINLOCK, CONFIG_DEBUG_SPINLOCK_SLEEP all simultaneously
+    CONFIG_DEBUG_SPINLOCK, CONFIG_DEBUG_ATOMIC_SLEEP all simultaneously
     enabled.
 
 13: Has been build- and runtime tested with and without CONFIG_SMP and
diff --git a/Documentation/development-process/4.Coding b/Documentation/development-process/4.Coding
index f3f1a469443c..83f5f5b365a3 100644
--- a/Documentation/development-process/4.Coding
+++ b/Documentation/development-process/4.Coding
@@ -244,7 +244,7 @@ testing purposes.  In particular, you should turn on:
  - DEBUG_SLAB can find a variety of memory allocation and use errors; it
    should be used on most development kernels.
 
- - DEBUG_SPINLOCK, DEBUG_SPINLOCK_SLEEP, and DEBUG_MUTEXES will find a
+ - DEBUG_SPINLOCK, DEBUG_ATOMIC_SLEEP, and DEBUG_MUTEXES will find a
    number of common locking errors.
 
 There are quite a few other debugging options, some of which will be
diff --git a/Documentation/ja_JP/SubmitChecklist b/Documentation/ja_JP/SubmitChecklist
index 2df4576f1173..cb5507b1ac81 100644
--- a/Documentation/ja_JP/SubmitChecklist
+++ b/Documentation/ja_JP/SubmitChecklist
@@ -68,7 +68,7 @@ Linux カーネルパッチ投稿者向けチェックリスト
 
 12: CONFIG_PREEMPT, CONFIG_DEBUG_PREEMPT, CONFIG_DEBUG_SLAB,
     CONFIG_DEBUG_PAGEALLOC, CONFIG_DEBUG_MUTEXES, CONFIG_DEBUG_SPINLOCK,
-    CONFIG_DEBUG_SPINLOCK_SLEEP これら全てを同時に有効にして動作確認を
+    CONFIG_DEBUG_ATOMIC_SLEEP これら全てを同時に有効にして動作確認を
     行ってください。
 
 13: CONFIG_SMP, CONFIG_PREEMPT を有効にした場合と無効にした場合の両方で
diff --git a/Documentation/zh_CN/SubmitChecklist b/Documentation/zh_CN/SubmitChecklist
index 951415bbab0c..4c741d6bc048 100644
--- a/Documentation/zh_CN/SubmitChecklist
+++ b/Documentation/zh_CN/SubmitChecklist
@@ -67,7 +67,7 @@ Linux�ں��ύ�嵥
 
 12���Ѿ�ͨ��CONFIG_PREEMPT, CONFIG_DEBUG_PREEMPT,
     CONFIG_DEBUG_SLAB, CONFIG_DEBUG_PAGEALLOC, CONFIG_DEBUG_MUTEXES,
-    CONFIG_DEBUG_SPINLOCK, CONFIG_DEBUG_SPINLOCK_SLEEP���ԣ�����ͬʱ��
+    CONFIG_DEBUG_SPINLOCK, CONFIG_DEBUG_ATOMIC_SLEEP���ԣ�����ͬʱ��
     ʹ�ܡ�
 
 13���Ѿ�����������ʹ�û��߲�ʹ�� CONFIG_SMP �� CONFIG_PREEMPT����ִ��ʱ�䡣
diff --git a/include/linux/bit_spinlock.h b/include/linux/bit_spinlock.h
index b4326bfa684f..564d997e2168 100644
--- a/include/linux/bit_spinlock.h
+++ b/include/linux/bit_spinlock.h
@@ -88,7 +88,7 @@ static inline int bit_spin_is_locked(int bitnum, unsigned long *addr)
 {
 #if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK)
         return test_bit(bitnum, addr);
-#elif defined CONFIG_PREEMPT
+#elif defined CONFIG_PREEMPT_COUNT
         return preempt_count();
 #else
         return 1;
diff --git a/include/linux/hardirq.h b/include/linux/hardirq.h
index ba362171e8ae..f743883f769e 100644
--- a/include/linux/hardirq.h
+++ b/include/linux/hardirq.h
@@ -93,7 +93,7 @@
  */
 #define in_nmi()        (preempt_count() & NMI_MASK)
 
-#if defined(CONFIG_PREEMPT)
+#if defined(CONFIG_PREEMPT_COUNT)
 # define PREEMPT_CHECK_OFFSET 1
 #else
 # define PREEMPT_CHECK_OFFSET 0
@@ -115,7 +115,7 @@
 #define in_atomic_preempt_off() \
                 ((preempt_count() & ~PREEMPT_ACTIVE) != PREEMPT_CHECK_OFFSET)
 
-#ifdef CONFIG_PREEMPT
+#ifdef CONFIG_PREEMPT_COUNT
 # define preemptible()  (preempt_count() == 0 && !irqs_disabled())
 # define IRQ_EXIT_OFFSET (HARDIRQ_OFFSET-1)
 #else
diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index 953352a88336..567a6f7bbeed 100644
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -121,7 +121,7 @@ extern int _cond_resched(void);
 # define might_resched() do { } while (0)
 #endif
 
-#ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
+#ifdef CONFIG_DEBUG_ATOMIC_SLEEP
   void __might_sleep(const char *file, int line, int preempt_offset);
 /**
  * might_sleep - annotation for functions that can sleep
diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h
index 716875e53520..8e38d4c140ff 100644
--- a/include/linux/pagemap.h
+++ b/include/linux/pagemap.h
@@ -134,7 +134,7 @@ static inline int page_cache_get_speculative(struct page *page)
         VM_BUG_ON(in_interrupt());
 
 #if !defined(CONFIG_SMP) && defined(CONFIG_TREE_RCU)
-# ifdef CONFIG_PREEMPT
+# ifdef CONFIG_PREEMPT_COUNT
         VM_BUG_ON(!in_atomic());
 # endif
         /*
@@ -172,7 +172,7 @@ static inline int page_cache_add_speculative(struct page *page, int count)
         VM_BUG_ON(in_interrupt());
 
 #if !defined(CONFIG_SMP) && defined(CONFIG_TREE_RCU)
-# ifdef CONFIG_PREEMPT
+# ifdef CONFIG_PREEMPT_COUNT
         VM_BUG_ON(!in_atomic());
 # endif
         VM_BUG_ON(page_count(page) == 0);
diff --git a/include/linux/preempt.h b/include/linux/preempt.h
index 2e681d9555bd..58969b2a8a82 100644
--- a/include/linux/preempt.h
+++ b/include/linux/preempt.h
@@ -27,6 +27,21 @@
 
 asmlinkage void preempt_schedule(void);
 
+#define preempt_check_resched() \
+do { \
+        if (unlikely(test_thread_flag(TIF_NEED_RESCHED))) \
+                preempt_schedule(); \
+} while (0)
+
+#else /* !CONFIG_PREEMPT */
+
+#define preempt_check_resched()         do { } while (0)
+
+#endif /* CONFIG_PREEMPT */
+
+
+#ifdef CONFIG_PREEMPT_COUNT
+
 #define preempt_disable() \
 do { \
         inc_preempt_count(); \
@@ -39,12 +54,6 @@ do { \
         dec_preempt_count(); \
 } while (0)
 
-#define preempt_check_resched() \
-do { \
-        if (unlikely(test_thread_flag(TIF_NEED_RESCHED))) \
-                preempt_schedule(); \
-} while (0)
-
 #define preempt_enable() \
 do { \
         preempt_enable_no_resched(); \
@@ -80,18 +89,17 @@ do { \
         preempt_check_resched(); \
 } while (0)
 
-#else
+#else /* !CONFIG_PREEMPT_COUNT */
 
 #define preempt_disable()               do { } while (0)
 #define preempt_enable_no_resched()     do { } while (0)
 #define preempt_enable()                do { } while (0)
-#define preempt_check_resched()         do { } while (0)
 
 #define preempt_disable_notrace()               do { } while (0)
 #define preempt_enable_no_resched_notrace()     do { } while (0)
 #define preempt_enable_notrace()                do { } while (0)
 
-#endif
+#endif /* CONFIG_PREEMPT_COUNT */
 
 #ifdef CONFIG_PREEMPT_NOTIFIERS
 
diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h
index 99f9aa7c2804..8f4f881a0ad8 100644
--- a/include/linux/rcupdate.h
+++ b/include/linux/rcupdate.h
@@ -239,7 +239,7 @@ extern int rcu_read_lock_bh_held(void);
  * Check debug_lockdep_rcu_enabled() to prevent false positives during boot
  * and while lockdep is disabled.
  */
-#ifdef CONFIG_PREEMPT
+#ifdef CONFIG_PREEMPT_COUNT
 static inline int rcu_read_lock_sched_held(void)
 {
         int lockdep_opinion = 0;
@@ -250,12 +250,12 @@ static inline int rcu_read_lock_sched_held(void)
                 lockdep_opinion = lock_is_held(&rcu_sched_lock_map);
         return lockdep_opinion || preempt_count() != 0 || irqs_disabled();
 }
-#else /* #ifdef CONFIG_PREEMPT */
+#else /* #ifdef CONFIG_PREEMPT_COUNT */
 static inline int rcu_read_lock_sched_held(void)
 {
         return 1;
 }
-#endif /* #else #ifdef CONFIG_PREEMPT */
+#endif /* #else #ifdef CONFIG_PREEMPT_COUNT */
 
 #else /* #ifdef CONFIG_DEBUG_LOCK_ALLOC */
 
@@ -276,17 +276,17 @@ static inline int rcu_read_lock_bh_held(void)
         return 1;
 }
 
-#ifdef CONFIG_PREEMPT
+#ifdef CONFIG_PREEMPT_COUNT
 static inline int rcu_read_lock_sched_held(void)
 {
         return preempt_count() != 0 || irqs_disabled();
 }
-#else /* #ifdef CONFIG_PREEMPT */
+#else /* #ifdef CONFIG_PREEMPT_COUNT */
 static inline int rcu_read_lock_sched_held(void)
 {
         return 1;
 }
-#endif /* #else #ifdef CONFIG_PREEMPT */
+#endif /* #else #ifdef CONFIG_PREEMPT_COUNT */
 
 #endif /* #else #ifdef CONFIG_DEBUG_LOCK_ALLOC */
 
diff --git a/include/linux/sched.h b/include/linux/sched.h
index a837b20ba190..9a9beef3c0fd 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -2501,7 +2501,7 @@ extern int _cond_resched(void);
 
 extern int __cond_resched_lock(spinlock_t *lock);
 
-#ifdef CONFIG_PREEMPT
+#ifdef CONFIG_PREEMPT_COUNT
 #define PREEMPT_LOCK_OFFSET     PREEMPT_OFFSET
 #else
 #define PREEMPT_LOCK_OFFSET     0
diff --git a/kernel/Kconfig.preempt b/kernel/Kconfig.preempt
index bf987b95b356..24e7cb0ba26a 100644
--- a/kernel/Kconfig.preempt
+++ b/kernel/Kconfig.preempt
@@ -35,6 +35,7 @@ config PREEMPT_VOLUNTARY
 
 config PREEMPT
         bool "Preemptible Kernel (Low-Latency Desktop)"
+        select PREEMPT_COUNT
         help
           This option reduces the latency of the kernel by making
           all kernel code (that is not executing in a critical section)
@@ -52,3 +53,5 @@ config PREEMPT
 
 endchoice
 
+config PREEMPT_COUNT
+       bool
\ No newline at end of file
diff --git a/kernel/sched.c b/kernel/sched.c
index e355ee72e83f..4380a80c1e7a 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -2854,7 +2854,7 @@ void sched_fork(struct task_struct *p)
 #if defined(CONFIG_SMP)
         p->on_cpu = 0;
 #endif
-#ifdef CONFIG_PREEMPT
+#ifdef CONFIG_PREEMPT_COUNT
         /* Want to start with kernel preemption disabled. */
         task_thread_info(p)->preempt_count = 1;
 #endif
@@ -8022,7 +8022,7 @@ void __init sched_init(void)
         scheduler_running = 1;
 }
 
-#ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
+#ifdef CONFIG_DEBUG_ATOMIC_SLEEP
 static inline int preempt_count_equals(int preempt_offset)
 {
         int nested = (preempt_count() & ~PREEMPT_ACTIVE) + rcu_preempt_depth();
@@ -8032,7 +8032,6 @@ static inline int preempt_count_equals(int preempt_offset)
 
 void __might_sleep(const char *file, int line, int preempt_offset)
 {
-#ifdef in_atomic
         static unsigned long prev_jiffy;        /* ratelimiting */
 
         if ((preempt_count_equals(preempt_offset) && !irqs_disabled()) ||
@@ -8054,7 +8053,6 @@ void __might_sleep(const char *file, int line, int preempt_offset)
         if (irqs_disabled())
                 print_irqtrace_events(current);
         dump_stack();
-#endif
 }
 EXPORT_SYMBOL(__might_sleep);
 #endif
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index dd373c8ee943..9f0d826cadc3 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -648,12 +648,15 @@ config TRACE_IRQFLAGS
           Enables hooks to interrupt enabling and disabling for
           either tracing or lock debugging.
 
-config DEBUG_SPINLOCK_SLEEP
-        bool "Spinlock debugging: sleep-inside-spinlock checking"
+config DEBUG_ATOMIC_SLEEP
+        bool "Sleep inside atomic section checking"
+        select PREEMPT_COUNT
         depends on DEBUG_KERNEL
         help
           If you say Y here, various routines which may sleep will become very
-          noisy if they are called with a spinlock held.
+          noisy if they are called inside atomic sections: when a spinlock is
+          held, inside an rcu read side critical section, inside preempt disabled
+          sections, inside an interrupt, etc...
 
 config DEBUG_LOCKING_API_SELFTESTS
         bool "Locking API boot-time self-tests"