summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorArjan van de Ven <arjan@linux.intel.com>2006-11-25 20:09:37 +0100
committerLinus Torvalds <torvalds@woody.osdl.org>2006-11-25 22:28:34 +0100
commitcfd3ef2346f924d6c0e82236c20fdb3a8840136a (patch)
treef0289367f0dbf80a5bcfa2969f428c605c54dd6a
parent[PATCH] Enforce "unsigned long flags;" when spinlocking (diff)
downloadlinux-cfd3ef2346f924d6c0e82236c20fdb3a8840136a.tar.xz
linux-cfd3ef2346f924d6c0e82236c20fdb3a8840136a.zip
[PATCH] lockdep: spin_lock_irqsave_nested()
Introduce spin_lock_irqsave_nested(); implementation from: http://lkml.org/lkml/2006/6/1/122 Patch from: http://lkml.org/lkml/2006/9/13/258 [akpm@osdl.org: two compile fixes] Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Jiri Kosina <jikos@jikos.cz> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
-rw-r--r--include/linux/spinlock.h18
-rw-r--r--include/linux/spinlock_api_smp.h2
-rw-r--r--kernel/spinlock.c21
3 files changed, 41 insertions, 0 deletions
diff --git a/include/linux/spinlock.h b/include/linux/spinlock.h
index 54ad37089c49..57f670d78f7c 100644
--- a/include/linux/spinlock.h
+++ b/include/linux/spinlock.h
@@ -199,6 +199,21 @@ do { \
BUILD_CHECK_IRQ_FLAGS(flags); \
flags = _write_lock_irqsave(lock); \
} while (0)
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+#define spin_lock_irqsave_nested(lock, flags, subclass) \
+ do { \
+ BUILD_CHECK_IRQ_FLAGS(flags); \
+ flags = _spin_lock_irqsave_nested(lock, subclass); \
+ } while (0)
+#else
+#define spin_lock_irqsave_nested(lock, flags, subclass) \
+ do { \
+ BUILD_CHECK_IRQ_FLAGS(flags); \
+ flags = _spin_lock_irqsave(lock); \
+ } while (0)
+#endif
+
#else
#define spin_lock_irqsave(lock, flags) \
do { \
@@ -215,6 +230,9 @@ do { \
BUILD_CHECK_IRQ_FLAGS(flags); \
_write_lock_irqsave(lock, flags); \
} while (0)
+#define spin_lock_irqsave_nested(lock, flags, subclass) \
+ spin_lock_irqsave(lock, flags)
+
#endif
#define spin_lock_irq(lock) _spin_lock_irq(lock)
diff --git a/include/linux/spinlock_api_smp.h b/include/linux/spinlock_api_smp.h
index 8828b8155e9c..8a2307ce7296 100644
--- a/include/linux/spinlock_api_smp.h
+++ b/include/linux/spinlock_api_smp.h
@@ -32,6 +32,8 @@ void __lockfunc _read_lock_irq(rwlock_t *lock) __acquires(lock);
void __lockfunc _write_lock_irq(rwlock_t *lock) __acquires(lock);
unsigned long __lockfunc _spin_lock_irqsave(spinlock_t *lock)
__acquires(lock);
+unsigned long __lockfunc _spin_lock_irqsave_nested(spinlock_t *lock, int subclass)
+ __acquires(lock);
unsigned long __lockfunc _read_lock_irqsave(rwlock_t *lock)
__acquires(lock);
unsigned long __lockfunc _write_lock_irqsave(rwlock_t *lock)
diff --git a/kernel/spinlock.c b/kernel/spinlock.c
index 476c3741511b..2c6c2bf85514 100644
--- a/kernel/spinlock.c
+++ b/kernel/spinlock.c
@@ -293,6 +293,27 @@ void __lockfunc _spin_lock_nested(spinlock_t *lock, int subclass)
}
EXPORT_SYMBOL(_spin_lock_nested);
+unsigned long __lockfunc _spin_lock_irqsave_nested(spinlock_t *lock, int subclass)
+{
+ unsigned long flags;
+
+ local_irq_save(flags);
+ preempt_disable();
+ spin_acquire(&lock->dep_map, subclass, 0, _RET_IP_);
+ /*
+ * On lockdep we dont want the hand-coded irq-enable of
+ * _raw_spin_lock_flags() code, because lockdep assumes
+ * that interrupts are not re-enabled during lock-acquire:
+ */
+#ifdef CONFIG_PROVE_SPIN_LOCKING
+ _raw_spin_lock(lock);
+#else
+ _raw_spin_lock_flags(lock, &flags);
+#endif
+ return flags;
+}
+
+EXPORT_SYMBOL(_spin_lock_irqsave_nested);
#endif