[RFC 3/8] locking: Move spinlock into kernel/locking/
From: Peter Zijlstra
Date: Tue Nov 05 2013 - 07:24:47 EST
Suggested-by: Ingo Molnar <mingo@xxxxxxxxxx>
Signed-off-by: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
---
kernel/Makefile | 3
kernel/locking/Makefile | 4
kernel/locking/spinlock.c | 399 ++++++++++++++++++++++++++++++++++++++++
kernel/locking/spinlock_debug.c | 302 ++++++++++++++++++++++++++++++
kernel/spinlock.c | 399 ----------------------------------------
lib/Makefile | 1
lib/spinlock_debug.c | 302 ------------------------------
7 files changed, 705 insertions(+), 705 deletions(-)
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -43,9 +43,6 @@ obj-$(CONFIG_SMP) += smp.o
ifneq ($(CONFIG_SMP),y)
obj-y += up.o
endif
-obj-$(CONFIG_SMP) += spinlock.o
-obj-$(CONFIG_DEBUG_SPINLOCK) += spinlock.o
-obj-$(CONFIG_PROVE_LOCKING) += spinlock.o
obj-$(CONFIG_UID16) += uid16.o
obj-$(CONFIG_SYSTEM_TRUSTED_KEYRING) += system_keyring.o system_certificates.o
obj-$(CONFIG_MODULES) += module.o
--- a/kernel/locking/Makefile
+++ b/kernel/locking/Makefile
@@ -13,3 +13,7 @@ obj-$(CONFIG_LOCKDEP) += lockdep.o
ifeq ($(CONFIG_PROC_FS),y)
obj-$(CONFIG_LOCKDEP) += lockdep_proc.o
endif
+obj-$(CONFIG_SMP) += spinlock.o
+obj-$(CONFIG_PROVE_LOCKING) += spinlock.o
+obj-$(CONFIG_DEBUG_SPINLOCK) += spinlock.o
+obj-$(CONFIG_DEBUG_SPINLOCK) += spinlock_debug.o
--- /dev/null
+++ b/kernel/locking/spinlock.c
@@ -0,0 +1,399 @@
+/*
+ * Copyright (2004) Linus Torvalds
+ *
+ * Author: Zwane Mwaikambo <zwane@xxxxxxxxxxx>
+ *
+ * Copyright (2004, 2005) Ingo Molnar
+ *
+ * This file contains the spinlock/rwlock implementations for the
+ * SMP and the DEBUG_SPINLOCK cases. (UP-nondebug inlines them)
+ *
+ * Note that some architectures have special knowledge about the
+ * stack frames of these functions in their profile_pc. If you
+ * change anything significant here that could change the stack
+ * frame contact the architecture maintainers.
+ */
+
+#include <linux/linkage.h>
+#include <linux/preempt.h>
+#include <linux/spinlock.h>
+#include <linux/interrupt.h>
+#include <linux/debug_locks.h>
+#include <linux/export.h>
+
+/*
+ * If lockdep is enabled then we use the non-preemption spin-ops
+ * even on CONFIG_PREEMPT, because lockdep assumes that interrupts are
+ * not re-enabled during lock-acquire (which the preempt-spin-ops do):
+ */
+#if !defined(CONFIG_GENERIC_LOCKBREAK) || defined(CONFIG_DEBUG_LOCK_ALLOC)
+/*
+ * The __lock_function inlines are taken from
+ * include/linux/spinlock_api_smp.h
+ */
+#else
+#define raw_read_can_lock(l) read_can_lock(l)
+#define raw_write_can_lock(l) write_can_lock(l)
+
+/*
+ * Some architectures can relax in favour of the CPU owning the lock.
+ */
+#ifndef arch_read_relax
+# define arch_read_relax(l) cpu_relax()
+#endif
+#ifndef arch_write_relax
+# define arch_write_relax(l) cpu_relax()
+#endif
+#ifndef arch_spin_relax
+# define arch_spin_relax(l) cpu_relax()
+#endif
+
+/*
+ * We build the __lock_function inlines here. They are too large for
+ * inlining all over the place, but here is only one user per function
+ * which embedds them into the calling _lock_function below.
+ *
+ * This could be a long-held lock. We both prepare to spin for a long
+ * time (making _this_ CPU preemptable if possible), and we also signal
+ * towards that other CPU that it should break the lock ASAP.
+ */
+#define BUILD_LOCK_OPS(op, locktype) \
+void __lockfunc __raw_##op##_lock(locktype##_t *lock) \
+{ \
+ for (;;) { \
+ preempt_disable(); \
+ if (likely(do_raw_##op##_trylock(lock))) \
+ break; \
+ preempt_enable(); \
+ \
+ if (!(lock)->break_lock) \
+ (lock)->break_lock = 1; \
+ while (!raw_##op##_can_lock(lock) && (lock)->break_lock)\
+ arch_##op##_relax(&lock->raw_lock); \
+ } \
+ (lock)->break_lock = 0; \
+} \
+ \
+unsigned long __lockfunc __raw_##op##_lock_irqsave(locktype##_t *lock) \
+{ \
+ unsigned long flags; \
+ \
+ for (;;) { \
+ preempt_disable(); \
+ local_irq_save(flags); \
+ if (likely(do_raw_##op##_trylock(lock))) \
+ break; \
+ local_irq_restore(flags); \
+ preempt_enable(); \
+ \
+ if (!(lock)->break_lock) \
+ (lock)->break_lock = 1; \
+ while (!raw_##op##_can_lock(lock) && (lock)->break_lock)\
+ arch_##op##_relax(&lock->raw_lock); \
+ } \
+ (lock)->break_lock = 0; \
+ return flags; \
+} \
+ \
+void __lockfunc __raw_##op##_lock_irq(locktype##_t *lock) \
+{ \
+ _raw_##op##_lock_irqsave(lock); \
+} \
+ \
+void __lockfunc __raw_##op##_lock_bh(locktype##_t *lock) \
+{ \
+ unsigned long flags; \
+ \
+ /* */ \
+ /* Careful: we must exclude softirqs too, hence the */ \
+ /* irq-disabling. We use the generic preemption-aware */ \
+ /* function: */ \
+ /**/ \
+ flags = _raw_##op##_lock_irqsave(lock); \
+ local_bh_disable(); \
+ local_irq_restore(flags); \
+} \
+
+/*
+ * Build preemption-friendly versions of the following
+ * lock-spinning functions:
+ *
+ * __[spin|read|write]_lock()
+ * __[spin|read|write]_lock_irq()
+ * __[spin|read|write]_lock_irqsave()
+ * __[spin|read|write]_lock_bh()
+ */
+BUILD_LOCK_OPS(spin, raw_spinlock);
+BUILD_LOCK_OPS(read, rwlock);
+BUILD_LOCK_OPS(write, rwlock);
+
+#endif
+
+#ifndef CONFIG_INLINE_SPIN_TRYLOCK
+int __lockfunc _raw_spin_trylock(raw_spinlock_t *lock)
+{
+ return __raw_spin_trylock(lock);
+}
+EXPORT_SYMBOL(_raw_spin_trylock);
+#endif
+
+#ifndef CONFIG_INLINE_SPIN_TRYLOCK_BH
+int __lockfunc _raw_spin_trylock_bh(raw_spinlock_t *lock)
+{
+ return __raw_spin_trylock_bh(lock);
+}
+EXPORT_SYMBOL(_raw_spin_trylock_bh);
+#endif
+
+#ifndef CONFIG_INLINE_SPIN_LOCK
+void __lockfunc _raw_spin_lock(raw_spinlock_t *lock)
+{
+ __raw_spin_lock(lock);
+}
+EXPORT_SYMBOL(_raw_spin_lock);
+#endif
+
+#ifndef CONFIG_INLINE_SPIN_LOCK_IRQSAVE
+unsigned long __lockfunc _raw_spin_lock_irqsave(raw_spinlock_t *lock)
+{
+ return __raw_spin_lock_irqsave(lock);
+}
+EXPORT_SYMBOL(_raw_spin_lock_irqsave);
+#endif
+
+#ifndef CONFIG_INLINE_SPIN_LOCK_IRQ
+void __lockfunc _raw_spin_lock_irq(raw_spinlock_t *lock)
+{
+ __raw_spin_lock_irq(lock);
+}
+EXPORT_SYMBOL(_raw_spin_lock_irq);
+#endif
+
+#ifndef CONFIG_INLINE_SPIN_LOCK_BH
+void __lockfunc _raw_spin_lock_bh(raw_spinlock_t *lock)
+{
+ __raw_spin_lock_bh(lock);
+}
+EXPORT_SYMBOL(_raw_spin_lock_bh);
+#endif
+
+#ifdef CONFIG_UNINLINE_SPIN_UNLOCK
+void __lockfunc _raw_spin_unlock(raw_spinlock_t *lock)
+{
+ __raw_spin_unlock(lock);
+}
+EXPORT_SYMBOL(_raw_spin_unlock);
+#endif
+
+#ifndef CONFIG_INLINE_SPIN_UNLOCK_IRQRESTORE
+void __lockfunc _raw_spin_unlock_irqrestore(raw_spinlock_t *lock, unsigned long flags)
+{
+ __raw_spin_unlock_irqrestore(lock, flags);
+}
+EXPORT_SYMBOL(_raw_spin_unlock_irqrestore);
+#endif
+
+#ifndef CONFIG_INLINE_SPIN_UNLOCK_IRQ
+void __lockfunc _raw_spin_unlock_irq(raw_spinlock_t *lock)
+{
+ __raw_spin_unlock_irq(lock);
+}
+EXPORT_SYMBOL(_raw_spin_unlock_irq);
+#endif
+
+#ifndef CONFIG_INLINE_SPIN_UNLOCK_BH
+void __lockfunc _raw_spin_unlock_bh(raw_spinlock_t *lock)
+{
+ __raw_spin_unlock_bh(lock);
+}
+EXPORT_SYMBOL(_raw_spin_unlock_bh);
+#endif
+
+#ifndef CONFIG_INLINE_READ_TRYLOCK
+int __lockfunc _raw_read_trylock(rwlock_t *lock)
+{
+ return __raw_read_trylock(lock);
+}
+EXPORT_SYMBOL(_raw_read_trylock);
+#endif
+
+#ifndef CONFIG_INLINE_READ_LOCK
+void __lockfunc _raw_read_lock(rwlock_t *lock)
+{
+ __raw_read_lock(lock);
+}
+EXPORT_SYMBOL(_raw_read_lock);
+#endif
+
+#ifndef CONFIG_INLINE_READ_LOCK_IRQSAVE
+unsigned long __lockfunc _raw_read_lock_irqsave(rwlock_t *lock)
+{
+ return __raw_read_lock_irqsave(lock);
+}
+EXPORT_SYMBOL(_raw_read_lock_irqsave);
+#endif
+
+#ifndef CONFIG_INLINE_READ_LOCK_IRQ
+void __lockfunc _raw_read_lock_irq(rwlock_t *lock)
+{
+ __raw_read_lock_irq(lock);
+}
+EXPORT_SYMBOL(_raw_read_lock_irq);
+#endif
+
+#ifndef CONFIG_INLINE_READ_LOCK_BH
+void __lockfunc _raw_read_lock_bh(rwlock_t *lock)
+{
+ __raw_read_lock_bh(lock);
+}
+EXPORT_SYMBOL(_raw_read_lock_bh);
+#endif
+
+#ifndef CONFIG_INLINE_READ_UNLOCK
+void __lockfunc _raw_read_unlock(rwlock_t *lock)
+{
+ __raw_read_unlock(lock);
+}
+EXPORT_SYMBOL(_raw_read_unlock);
+#endif
+
+#ifndef CONFIG_INLINE_READ_UNLOCK_IRQRESTORE
+void __lockfunc _raw_read_unlock_irqrestore(rwlock_t *lock, unsigned long flags)
+{
+ __raw_read_unlock_irqrestore(lock, flags);
+}
+EXPORT_SYMBOL(_raw_read_unlock_irqrestore);
+#endif
+
+#ifndef CONFIG_INLINE_READ_UNLOCK_IRQ
+void __lockfunc _raw_read_unlock_irq(rwlock_t *lock)
+{
+ __raw_read_unlock_irq(lock);
+}
+EXPORT_SYMBOL(_raw_read_unlock_irq);
+#endif
+
+#ifndef CONFIG_INLINE_READ_UNLOCK_BH
+void __lockfunc _raw_read_unlock_bh(rwlock_t *lock)
+{
+ __raw_read_unlock_bh(lock);
+}
+EXPORT_SYMBOL(_raw_read_unlock_bh);
+#endif
+
+#ifndef CONFIG_INLINE_WRITE_TRYLOCK
+int __lockfunc _raw_write_trylock(rwlock_t *lock)
+{
+ return __raw_write_trylock(lock);
+}
+EXPORT_SYMBOL(_raw_write_trylock);
+#endif
+
+#ifndef CONFIG_INLINE_WRITE_LOCK
+void __lockfunc _raw_write_lock(rwlock_t *lock)
+{
+ __raw_write_lock(lock);
+}
+EXPORT_SYMBOL(_raw_write_lock);
+#endif
+
+#ifndef CONFIG_INLINE_WRITE_LOCK_IRQSAVE
+unsigned long __lockfunc _raw_write_lock_irqsave(rwlock_t *lock)
+{
+ return __raw_write_lock_irqsave(lock);
+}
+EXPORT_SYMBOL(_raw_write_lock_irqsave);
+#endif
+
+#ifndef CONFIG_INLINE_WRITE_LOCK_IRQ
+void __lockfunc _raw_write_lock_irq(rwlock_t *lock)
+{
+ __raw_write_lock_irq(lock);
+}
+EXPORT_SYMBOL(_raw_write_lock_irq);
+#endif
+
+#ifndef CONFIG_INLINE_WRITE_LOCK_BH
+void __lockfunc _raw_write_lock_bh(rwlock_t *lock)
+{
+ __raw_write_lock_bh(lock);
+}
+EXPORT_SYMBOL(_raw_write_lock_bh);
+#endif
+
+#ifndef CONFIG_INLINE_WRITE_UNLOCK
+void __lockfunc _raw_write_unlock(rwlock_t *lock)
+{
+ __raw_write_unlock(lock);
+}
+EXPORT_SYMBOL(_raw_write_unlock);
+#endif
+
+#ifndef CONFIG_INLINE_WRITE_UNLOCK_IRQRESTORE
+void __lockfunc _raw_write_unlock_irqrestore(rwlock_t *lock, unsigned long flags)
+{
+ __raw_write_unlock_irqrestore(lock, flags);
+}
+EXPORT_SYMBOL(_raw_write_unlock_irqrestore);
+#endif
+
+#ifndef CONFIG_INLINE_WRITE_UNLOCK_IRQ
+void __lockfunc _raw_write_unlock_irq(rwlock_t *lock)
+{
+ __raw_write_unlock_irq(lock);
+}
+EXPORT_SYMBOL(_raw_write_unlock_irq);
+#endif
+
+#ifndef CONFIG_INLINE_WRITE_UNLOCK_BH
+void __lockfunc _raw_write_unlock_bh(rwlock_t *lock)
+{
+ __raw_write_unlock_bh(lock);
+}
+EXPORT_SYMBOL(_raw_write_unlock_bh);
+#endif
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+
+void __lockfunc _raw_spin_lock_nested(raw_spinlock_t *lock, int subclass)
+{
+ preempt_disable();
+ spin_acquire(&lock->dep_map, subclass, 0, _RET_IP_);
+ LOCK_CONTENDED(lock, do_raw_spin_trylock, do_raw_spin_lock);
+}
+EXPORT_SYMBOL(_raw_spin_lock_nested);
+
+unsigned long __lockfunc _raw_spin_lock_irqsave_nested(raw_spinlock_t *lock,
+ int subclass)
+{
+ unsigned long flags;
+
+ local_irq_save(flags);
+ preempt_disable();
+ spin_acquire(&lock->dep_map, subclass, 0, _RET_IP_);
+ LOCK_CONTENDED_FLAGS(lock, do_raw_spin_trylock, do_raw_spin_lock,
+ do_raw_spin_lock_flags, &flags);
+ return flags;
+}
+EXPORT_SYMBOL(_raw_spin_lock_irqsave_nested);
+
+void __lockfunc _raw_spin_lock_nest_lock(raw_spinlock_t *lock,
+ struct lockdep_map *nest_lock)
+{
+ preempt_disable();
+ spin_acquire_nest(&lock->dep_map, 0, 0, nest_lock, _RET_IP_);
+ LOCK_CONTENDED(lock, do_raw_spin_trylock, do_raw_spin_lock);
+}
+EXPORT_SYMBOL(_raw_spin_lock_nest_lock);
+
+#endif
+
+notrace int in_lock_functions(unsigned long addr)
+{
+ /* Linker adds these: start and end of __lockfunc functions */
+ extern char __lock_text_start[], __lock_text_end[];
+
+ return addr >= (unsigned long)__lock_text_start
+ && addr < (unsigned long)__lock_text_end;
+}
+EXPORT_SYMBOL(in_lock_functions);
--- /dev/null
+++ b/kernel/locking/spinlock_debug.c
@@ -0,0 +1,302 @@
+/*
+ * Copyright 2005, Red Hat, Inc., Ingo Molnar
+ * Released under the General Public License (GPL).
+ *
+ * This file contains the spinlock/rwlock implementations for
+ * DEBUG_SPINLOCK.
+ */
+
+#include <linux/spinlock.h>
+#include <linux/nmi.h>
+#include <linux/interrupt.h>
+#include <linux/debug_locks.h>
+#include <linux/delay.h>
+#include <linux/export.h>
+
+void __raw_spin_lock_init(raw_spinlock_t *lock, const char *name,
+ struct lock_class_key *key)
+{
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+ /*
+ * Make sure we are not reinitializing a held lock:
+ */
+ debug_check_no_locks_freed((void *)lock, sizeof(*lock));
+ lockdep_init_map(&lock->dep_map, name, key, 0);
+#endif
+ lock->raw_lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED;
+ lock->magic = SPINLOCK_MAGIC;
+ lock->owner = SPINLOCK_OWNER_INIT;
+ lock->owner_cpu = -1;
+}
+
+EXPORT_SYMBOL(__raw_spin_lock_init);
+
+void __rwlock_init(rwlock_t *lock, const char *name,
+ struct lock_class_key *key)
+{
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+ /*
+ * Make sure we are not reinitializing a held lock:
+ */
+ debug_check_no_locks_freed((void *)lock, sizeof(*lock));
+ lockdep_init_map(&lock->dep_map, name, key, 0);
+#endif
+ lock->raw_lock = (arch_rwlock_t) __ARCH_RW_LOCK_UNLOCKED;
+ lock->magic = RWLOCK_MAGIC;
+ lock->owner = SPINLOCK_OWNER_INIT;
+ lock->owner_cpu = -1;
+}
+
+EXPORT_SYMBOL(__rwlock_init);
+
+static void spin_dump(raw_spinlock_t *lock, const char *msg)
+{
+ struct task_struct *owner = NULL;
+
+ if (lock->owner && lock->owner != SPINLOCK_OWNER_INIT)
+ owner = lock->owner;
+ printk(KERN_EMERG "BUG: spinlock %s on CPU#%d, %s/%d\n",
+ msg, raw_smp_processor_id(),
+ current->comm, task_pid_nr(current));
+ printk(KERN_EMERG " lock: %pS, .magic: %08x, .owner: %s/%d, "
+ ".owner_cpu: %d\n",
+ lock, lock->magic,
+ owner ? owner->comm : "<none>",
+ owner ? task_pid_nr(owner) : -1,
+ lock->owner_cpu);
+ dump_stack();
+}
+
+static void spin_bug(raw_spinlock_t *lock, const char *msg)
+{
+ if (!debug_locks_off())
+ return;
+
+ spin_dump(lock, msg);
+}
+
+#define SPIN_BUG_ON(cond, lock, msg) if (unlikely(cond)) spin_bug(lock, msg)
+
+static inline void
+debug_spin_lock_before(raw_spinlock_t *lock)
+{
+ SPIN_BUG_ON(lock->magic != SPINLOCK_MAGIC, lock, "bad magic");
+ SPIN_BUG_ON(lock->owner == current, lock, "recursion");
+ SPIN_BUG_ON(lock->owner_cpu == raw_smp_processor_id(),
+ lock, "cpu recursion");
+}
+
+static inline void debug_spin_lock_after(raw_spinlock_t *lock)
+{
+ lock->owner_cpu = raw_smp_processor_id();
+ lock->owner = current;
+}
+
+static inline void debug_spin_unlock(raw_spinlock_t *lock)
+{
+ SPIN_BUG_ON(lock->magic != SPINLOCK_MAGIC, lock, "bad magic");
+ SPIN_BUG_ON(!raw_spin_is_locked(lock), lock, "already unlocked");
+ SPIN_BUG_ON(lock->owner != current, lock, "wrong owner");
+ SPIN_BUG_ON(lock->owner_cpu != raw_smp_processor_id(),
+ lock, "wrong CPU");
+ lock->owner = SPINLOCK_OWNER_INIT;
+ lock->owner_cpu = -1;
+}
+
+static void __spin_lock_debug(raw_spinlock_t *lock)
+{
+ u64 i;
+ u64 loops = loops_per_jiffy * HZ;
+
+ for (i = 0; i < loops; i++) {
+ if (arch_spin_trylock(&lock->raw_lock))
+ return;
+ __delay(1);
+ }
+ /* lockup suspected: */
+ spin_dump(lock, "lockup suspected");
+#ifdef CONFIG_SMP
+ trigger_all_cpu_backtrace();
+#endif
+
+ /*
+ * The trylock above was causing a livelock. Give the lower level arch
+ * specific lock code a chance to acquire the lock. We have already
+ * printed a warning/backtrace at this point. The non-debug arch
+ * specific code might actually succeed in acquiring the lock. If it is
+ * not successful, the end-result is the same - there is no forward
+ * progress.
+ */
+ arch_spin_lock(&lock->raw_lock);
+}
+
+void do_raw_spin_lock(raw_spinlock_t *lock)
+{
+ debug_spin_lock_before(lock);
+ if (unlikely(!arch_spin_trylock(&lock->raw_lock)))
+ __spin_lock_debug(lock);
+ debug_spin_lock_after(lock);
+}
+
+int do_raw_spin_trylock(raw_spinlock_t *lock)
+{
+ int ret = arch_spin_trylock(&lock->raw_lock);
+
+ if (ret)
+ debug_spin_lock_after(lock);
+#ifndef CONFIG_SMP
+ /*
+ * Must not happen on UP:
+ */
+ SPIN_BUG_ON(!ret, lock, "trylock failure on UP");
+#endif
+ return ret;
+}
+
+void do_raw_spin_unlock(raw_spinlock_t *lock)
+{
+ debug_spin_unlock(lock);
+ arch_spin_unlock(&lock->raw_lock);
+}
+
+static void rwlock_bug(rwlock_t *lock, const char *msg)
+{
+ if (!debug_locks_off())
+ return;
+
+ printk(KERN_EMERG "BUG: rwlock %s on CPU#%d, %s/%d, %p\n",
+ msg, raw_smp_processor_id(), current->comm,
+ task_pid_nr(current), lock);
+ dump_stack();
+}
+
+#define RWLOCK_BUG_ON(cond, lock, msg) if (unlikely(cond)) rwlock_bug(lock, msg)
+
+#if 0 /* __write_lock_debug() can lock up - maybe this can too? */
+static void __read_lock_debug(rwlock_t *lock)
+{
+ u64 i;
+ u64 loops = loops_per_jiffy * HZ;
+ int print_once = 1;
+
+ for (;;) {
+ for (i = 0; i < loops; i++) {
+ if (arch_read_trylock(&lock->raw_lock))
+ return;
+ __delay(1);
+ }
+ /* lockup suspected: */
+ if (print_once) {
+ print_once = 0;
+ printk(KERN_EMERG "BUG: read-lock lockup on CPU#%d, "
+ "%s/%d, %p\n",
+ raw_smp_processor_id(), current->comm,
+ current->pid, lock);
+ dump_stack();
+ }
+ }
+}
+#endif
+
+void do_raw_read_lock(rwlock_t *lock)
+{
+ RWLOCK_BUG_ON(lock->magic != RWLOCK_MAGIC, lock, "bad magic");
+ arch_read_lock(&lock->raw_lock);
+}
+
+int do_raw_read_trylock(rwlock_t *lock)
+{
+ int ret = arch_read_trylock(&lock->raw_lock);
+
+#ifndef CONFIG_SMP
+ /*
+ * Must not happen on UP:
+ */
+ RWLOCK_BUG_ON(!ret, lock, "trylock failure on UP");
+#endif
+ return ret;
+}
+
+void do_raw_read_unlock(rwlock_t *lock)
+{
+ RWLOCK_BUG_ON(lock->magic != RWLOCK_MAGIC, lock, "bad magic");
+ arch_read_unlock(&lock->raw_lock);
+}
+
+static inline void debug_write_lock_before(rwlock_t *lock)
+{
+ RWLOCK_BUG_ON(lock->magic != RWLOCK_MAGIC, lock, "bad magic");
+ RWLOCK_BUG_ON(lock->owner == current, lock, "recursion");
+ RWLOCK_BUG_ON(lock->owner_cpu == raw_smp_processor_id(),
+ lock, "cpu recursion");
+}
+
+static inline void debug_write_lock_after(rwlock_t *lock)
+{
+ lock->owner_cpu = raw_smp_processor_id();
+ lock->owner = current;
+}
+
+static inline void debug_write_unlock(rwlock_t *lock)
+{
+ RWLOCK_BUG_ON(lock->magic != RWLOCK_MAGIC, lock, "bad magic");
+ RWLOCK_BUG_ON(lock->owner != current, lock, "wrong owner");
+ RWLOCK_BUG_ON(lock->owner_cpu != raw_smp_processor_id(),
+ lock, "wrong CPU");
+ lock->owner = SPINLOCK_OWNER_INIT;
+ lock->owner_cpu = -1;
+}
+
+#if 0 /* This can cause lockups */
+static void __write_lock_debug(rwlock_t *lock)
+{
+ u64 i;
+ u64 loops = loops_per_jiffy * HZ;
+ int print_once = 1;
+
+ for (;;) {
+ for (i = 0; i < loops; i++) {
+ if (arch_write_trylock(&lock->raw_lock))
+ return;
+ __delay(1);
+ }
+ /* lockup suspected: */
+ if (print_once) {
+ print_once = 0;
+ printk(KERN_EMERG "BUG: write-lock lockup on CPU#%d, "
+ "%s/%d, %p\n",
+ raw_smp_processor_id(), current->comm,
+ current->pid, lock);
+ dump_stack();
+ }
+ }
+}
+#endif
+
+void do_raw_write_lock(rwlock_t *lock)
+{
+ debug_write_lock_before(lock);
+ arch_write_lock(&lock->raw_lock);
+ debug_write_lock_after(lock);
+}
+
+int do_raw_write_trylock(rwlock_t *lock)
+{
+ int ret = arch_write_trylock(&lock->raw_lock);
+
+ if (ret)
+ debug_write_lock_after(lock);
+#ifndef CONFIG_SMP
+ /*
+ * Must not happen on UP:
+ */
+ RWLOCK_BUG_ON(!ret, lock, "trylock failure on UP");
+#endif
+ return ret;
+}
+
+void do_raw_write_unlock(rwlock_t *lock)
+{
+ debug_write_unlock(lock);
+ arch_write_unlock(&lock->raw_lock);
+}
--- a/kernel/spinlock.c
+++ /dev/null
@@ -1,399 +0,0 @@
-/*
- * Copyright (2004) Linus Torvalds
- *
- * Author: Zwane Mwaikambo <zwane@xxxxxxxxxxx>
- *
- * Copyright (2004, 2005) Ingo Molnar
- *
- * This file contains the spinlock/rwlock implementations for the
- * SMP and the DEBUG_SPINLOCK cases. (UP-nondebug inlines them)
- *
- * Note that some architectures have special knowledge about the
- * stack frames of these functions in their profile_pc. If you
- * change anything significant here that could change the stack
- * frame contact the architecture maintainers.
- */
-
-#include <linux/linkage.h>
-#include <linux/preempt.h>
-#include <linux/spinlock.h>
-#include <linux/interrupt.h>
-#include <linux/debug_locks.h>
-#include <linux/export.h>
-
-/*
- * If lockdep is enabled then we use the non-preemption spin-ops
- * even on CONFIG_PREEMPT, because lockdep assumes that interrupts are
- * not re-enabled during lock-acquire (which the preempt-spin-ops do):
- */
-#if !defined(CONFIG_GENERIC_LOCKBREAK) || defined(CONFIG_DEBUG_LOCK_ALLOC)
-/*
- * The __lock_function inlines are taken from
- * include/linux/spinlock_api_smp.h
- */
-#else
-#define raw_read_can_lock(l) read_can_lock(l)
-#define raw_write_can_lock(l) write_can_lock(l)
-
-/*
- * Some architectures can relax in favour of the CPU owning the lock.
- */
-#ifndef arch_read_relax
-# define arch_read_relax(l) cpu_relax()
-#endif
-#ifndef arch_write_relax
-# define arch_write_relax(l) cpu_relax()
-#endif
-#ifndef arch_spin_relax
-# define arch_spin_relax(l) cpu_relax()
-#endif
-
-/*
- * We build the __lock_function inlines here. They are too large for
- * inlining all over the place, but here is only one user per function
- * which embedds them into the calling _lock_function below.
- *
- * This could be a long-held lock. We both prepare to spin for a long
- * time (making _this_ CPU preemptable if possible), and we also signal
- * towards that other CPU that it should break the lock ASAP.
- */
-#define BUILD_LOCK_OPS(op, locktype) \
-void __lockfunc __raw_##op##_lock(locktype##_t *lock) \
-{ \
- for (;;) { \
- preempt_disable(); \
- if (likely(do_raw_##op##_trylock(lock))) \
- break; \
- preempt_enable(); \
- \
- if (!(lock)->break_lock) \
- (lock)->break_lock = 1; \
- while (!raw_##op##_can_lock(lock) && (lock)->break_lock)\
- arch_##op##_relax(&lock->raw_lock); \
- } \
- (lock)->break_lock = 0; \
-} \
- \
-unsigned long __lockfunc __raw_##op##_lock_irqsave(locktype##_t *lock) \
-{ \
- unsigned long flags; \
- \
- for (;;) { \
- preempt_disable(); \
- local_irq_save(flags); \
- if (likely(do_raw_##op##_trylock(lock))) \
- break; \
- local_irq_restore(flags); \
- preempt_enable(); \
- \
- if (!(lock)->break_lock) \
- (lock)->break_lock = 1; \
- while (!raw_##op##_can_lock(lock) && (lock)->break_lock)\
- arch_##op##_relax(&lock->raw_lock); \
- } \
- (lock)->break_lock = 0; \
- return flags; \
-} \
- \
-void __lockfunc __raw_##op##_lock_irq(locktype##_t *lock) \
-{ \
- _raw_##op##_lock_irqsave(lock); \
-} \
- \
-void __lockfunc __raw_##op##_lock_bh(locktype##_t *lock) \
-{ \
- unsigned long flags; \
- \
- /* */ \
- /* Careful: we must exclude softirqs too, hence the */ \
- /* irq-disabling. We use the generic preemption-aware */ \
- /* function: */ \
- /**/ \
- flags = _raw_##op##_lock_irqsave(lock); \
- local_bh_disable(); \
- local_irq_restore(flags); \
-} \
-
-/*
- * Build preemption-friendly versions of the following
- * lock-spinning functions:
- *
- * __[spin|read|write]_lock()
- * __[spin|read|write]_lock_irq()
- * __[spin|read|write]_lock_irqsave()
- * __[spin|read|write]_lock_bh()
- */
-BUILD_LOCK_OPS(spin, raw_spinlock);
-BUILD_LOCK_OPS(read, rwlock);
-BUILD_LOCK_OPS(write, rwlock);
-
-#endif
-
-#ifndef CONFIG_INLINE_SPIN_TRYLOCK
-int __lockfunc _raw_spin_trylock(raw_spinlock_t *lock)
-{
- return __raw_spin_trylock(lock);
-}
-EXPORT_SYMBOL(_raw_spin_trylock);
-#endif
-
-#ifndef CONFIG_INLINE_SPIN_TRYLOCK_BH
-int __lockfunc _raw_spin_trylock_bh(raw_spinlock_t *lock)
-{
- return __raw_spin_trylock_bh(lock);
-}
-EXPORT_SYMBOL(_raw_spin_trylock_bh);
-#endif
-
-#ifndef CONFIG_INLINE_SPIN_LOCK
-void __lockfunc _raw_spin_lock(raw_spinlock_t *lock)
-{
- __raw_spin_lock(lock);
-}
-EXPORT_SYMBOL(_raw_spin_lock);
-#endif
-
-#ifndef CONFIG_INLINE_SPIN_LOCK_IRQSAVE
-unsigned long __lockfunc _raw_spin_lock_irqsave(raw_spinlock_t *lock)
-{
- return __raw_spin_lock_irqsave(lock);
-}
-EXPORT_SYMBOL(_raw_spin_lock_irqsave);
-#endif
-
-#ifndef CONFIG_INLINE_SPIN_LOCK_IRQ
-void __lockfunc _raw_spin_lock_irq(raw_spinlock_t *lock)
-{
- __raw_spin_lock_irq(lock);
-}
-EXPORT_SYMBOL(_raw_spin_lock_irq);
-#endif
-
-#ifndef CONFIG_INLINE_SPIN_LOCK_BH
-void __lockfunc _raw_spin_lock_bh(raw_spinlock_t *lock)
-{
- __raw_spin_lock_bh(lock);
-}
-EXPORT_SYMBOL(_raw_spin_lock_bh);
-#endif
-
-#ifdef CONFIG_UNINLINE_SPIN_UNLOCK
-void __lockfunc _raw_spin_unlock(raw_spinlock_t *lock)
-{
- __raw_spin_unlock(lock);
-}
-EXPORT_SYMBOL(_raw_spin_unlock);
-#endif
-
-#ifndef CONFIG_INLINE_SPIN_UNLOCK_IRQRESTORE
-void __lockfunc _raw_spin_unlock_irqrestore(raw_spinlock_t *lock, unsigned long flags)
-{
- __raw_spin_unlock_irqrestore(lock, flags);
-}
-EXPORT_SYMBOL(_raw_spin_unlock_irqrestore);
-#endif
-
-#ifndef CONFIG_INLINE_SPIN_UNLOCK_IRQ
-void __lockfunc _raw_spin_unlock_irq(raw_spinlock_t *lock)
-{
- __raw_spin_unlock_irq(lock);
-}
-EXPORT_SYMBOL(_raw_spin_unlock_irq);
-#endif
-
-#ifndef CONFIG_INLINE_SPIN_UNLOCK_BH
-void __lockfunc _raw_spin_unlock_bh(raw_spinlock_t *lock)
-{
- __raw_spin_unlock_bh(lock);
-}
-EXPORT_SYMBOL(_raw_spin_unlock_bh);
-#endif
-
-#ifndef CONFIG_INLINE_READ_TRYLOCK
-int __lockfunc _raw_read_trylock(rwlock_t *lock)
-{
- return __raw_read_trylock(lock);
-}
-EXPORT_SYMBOL(_raw_read_trylock);
-#endif
-
-#ifndef CONFIG_INLINE_READ_LOCK
-void __lockfunc _raw_read_lock(rwlock_t *lock)
-{
- __raw_read_lock(lock);
-}
-EXPORT_SYMBOL(_raw_read_lock);
-#endif
-
-#ifndef CONFIG_INLINE_READ_LOCK_IRQSAVE
-unsigned long __lockfunc _raw_read_lock_irqsave(rwlock_t *lock)
-{
- return __raw_read_lock_irqsave(lock);
-}
-EXPORT_SYMBOL(_raw_read_lock_irqsave);
-#endif
-
-#ifndef CONFIG_INLINE_READ_LOCK_IRQ
-void __lockfunc _raw_read_lock_irq(rwlock_t *lock)
-{
- __raw_read_lock_irq(lock);
-}
-EXPORT_SYMBOL(_raw_read_lock_irq);
-#endif
-
-#ifndef CONFIG_INLINE_READ_LOCK_BH
-void __lockfunc _raw_read_lock_bh(rwlock_t *lock)
-{
- __raw_read_lock_bh(lock);
-}
-EXPORT_SYMBOL(_raw_read_lock_bh);
-#endif
-
-#ifndef CONFIG_INLINE_READ_UNLOCK
-void __lockfunc _raw_read_unlock(rwlock_t *lock)
-{
- __raw_read_unlock(lock);
-}
-EXPORT_SYMBOL(_raw_read_unlock);
-#endif
-
-#ifndef CONFIG_INLINE_READ_UNLOCK_IRQRESTORE
-void __lockfunc _raw_read_unlock_irqrestore(rwlock_t *lock, unsigned long flags)
-{
- __raw_read_unlock_irqrestore(lock, flags);
-}
-EXPORT_SYMBOL(_raw_read_unlock_irqrestore);
-#endif
-
-#ifndef CONFIG_INLINE_READ_UNLOCK_IRQ
-void __lockfunc _raw_read_unlock_irq(rwlock_t *lock)
-{
- __raw_read_unlock_irq(lock);
-}
-EXPORT_SYMBOL(_raw_read_unlock_irq);
-#endif
-
-#ifndef CONFIG_INLINE_READ_UNLOCK_BH
-void __lockfunc _raw_read_unlock_bh(rwlock_t *lock)
-{
- __raw_read_unlock_bh(lock);
-}
-EXPORT_SYMBOL(_raw_read_unlock_bh);
-#endif
-
-#ifndef CONFIG_INLINE_WRITE_TRYLOCK
-int __lockfunc _raw_write_trylock(rwlock_t *lock)
-{
- return __raw_write_trylock(lock);
-}
-EXPORT_SYMBOL(_raw_write_trylock);
-#endif
-
-#ifndef CONFIG_INLINE_WRITE_LOCK
-void __lockfunc _raw_write_lock(rwlock_t *lock)
-{
- __raw_write_lock(lock);
-}
-EXPORT_SYMBOL(_raw_write_lock);
-#endif
-
-#ifndef CONFIG_INLINE_WRITE_LOCK_IRQSAVE
-unsigned long __lockfunc _raw_write_lock_irqsave(rwlock_t *lock)
-{
- return __raw_write_lock_irqsave(lock);
-}
-EXPORT_SYMBOL(_raw_write_lock_irqsave);
-#endif
-
-#ifndef CONFIG_INLINE_WRITE_LOCK_IRQ
-void __lockfunc _raw_write_lock_irq(rwlock_t *lock)
-{
- __raw_write_lock_irq(lock);
-}
-EXPORT_SYMBOL(_raw_write_lock_irq);
-#endif
-
-#ifndef CONFIG_INLINE_WRITE_LOCK_BH
-void __lockfunc _raw_write_lock_bh(rwlock_t *lock)
-{
- __raw_write_lock_bh(lock);
-}
-EXPORT_SYMBOL(_raw_write_lock_bh);
-#endif
-
-#ifndef CONFIG_INLINE_WRITE_UNLOCK
-void __lockfunc _raw_write_unlock(rwlock_t *lock)
-{
- __raw_write_unlock(lock);
-}
-EXPORT_SYMBOL(_raw_write_unlock);
-#endif
-
-#ifndef CONFIG_INLINE_WRITE_UNLOCK_IRQRESTORE
-void __lockfunc _raw_write_unlock_irqrestore(rwlock_t *lock, unsigned long flags)
-{
- __raw_write_unlock_irqrestore(lock, flags);
-}
-EXPORT_SYMBOL(_raw_write_unlock_irqrestore);
-#endif
-
-#ifndef CONFIG_INLINE_WRITE_UNLOCK_IRQ
-void __lockfunc _raw_write_unlock_irq(rwlock_t *lock)
-{
- __raw_write_unlock_irq(lock);
-}
-EXPORT_SYMBOL(_raw_write_unlock_irq);
-#endif
-
-#ifndef CONFIG_INLINE_WRITE_UNLOCK_BH
-void __lockfunc _raw_write_unlock_bh(rwlock_t *lock)
-{
- __raw_write_unlock_bh(lock);
-}
-EXPORT_SYMBOL(_raw_write_unlock_bh);
-#endif
-
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
-
-void __lockfunc _raw_spin_lock_nested(raw_spinlock_t *lock, int subclass)
-{
- preempt_disable();
- spin_acquire(&lock->dep_map, subclass, 0, _RET_IP_);
- LOCK_CONTENDED(lock, do_raw_spin_trylock, do_raw_spin_lock);
-}
-EXPORT_SYMBOL(_raw_spin_lock_nested);
-
-unsigned long __lockfunc _raw_spin_lock_irqsave_nested(raw_spinlock_t *lock,
- int subclass)
-{
- unsigned long flags;
-
- local_irq_save(flags);
- preempt_disable();
- spin_acquire(&lock->dep_map, subclass, 0, _RET_IP_);
- LOCK_CONTENDED_FLAGS(lock, do_raw_spin_trylock, do_raw_spin_lock,
- do_raw_spin_lock_flags, &flags);
- return flags;
-}
-EXPORT_SYMBOL(_raw_spin_lock_irqsave_nested);
-
-void __lockfunc _raw_spin_lock_nest_lock(raw_spinlock_t *lock,
- struct lockdep_map *nest_lock)
-{
- preempt_disable();
- spin_acquire_nest(&lock->dep_map, 0, 0, nest_lock, _RET_IP_);
- LOCK_CONTENDED(lock, do_raw_spin_trylock, do_raw_spin_lock);
-}
-EXPORT_SYMBOL(_raw_spin_lock_nest_lock);
-
-#endif
-
-notrace int in_lock_functions(unsigned long addr)
-{
- /* Linker adds these: start and end of __lockfunc functions */
- extern char __lock_text_start[], __lock_text_end[];
-
- return addr >= (unsigned long)__lock_text_start
- && addr < (unsigned long)__lock_text_end;
-}
-EXPORT_SYMBOL(in_lock_functions);
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -42,7 +42,6 @@ obj-$(CONFIG_GENERIC_PCI_IOMAP) += pci_i
obj-$(CONFIG_HAS_IOMEM) += iomap_copy.o devres.o
obj-$(CONFIG_CHECK_SIGNATURE) += check_signature.o
obj-$(CONFIG_DEBUG_LOCKING_API_SELFTESTS) += locking-selftest.o
-obj-$(CONFIG_DEBUG_SPINLOCK) += spinlock_debug.o
lib-$(CONFIG_RWSEM_GENERIC_SPINLOCK) += rwsem-spinlock.o
lib-$(CONFIG_RWSEM_XCHGADD_ALGORITHM) += rwsem.o
lib-$(CONFIG_PERCPU_RWSEM) += percpu-rwsem.o
--- a/lib/spinlock_debug.c
+++ /dev/null
@@ -1,302 +0,0 @@
-/*
- * Copyright 2005, Red Hat, Inc., Ingo Molnar
- * Released under the General Public License (GPL).
- *
- * This file contains the spinlock/rwlock implementations for
- * DEBUG_SPINLOCK.
- */
-
-#include <linux/spinlock.h>
-#include <linux/nmi.h>
-#include <linux/interrupt.h>
-#include <linux/debug_locks.h>
-#include <linux/delay.h>
-#include <linux/export.h>
-
-void __raw_spin_lock_init(raw_spinlock_t *lock, const char *name,
- struct lock_class_key *key)
-{
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
- /*
- * Make sure we are not reinitializing a held lock:
- */
- debug_check_no_locks_freed((void *)lock, sizeof(*lock));
- lockdep_init_map(&lock->dep_map, name, key, 0);
-#endif
- lock->raw_lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED;
- lock->magic = SPINLOCK_MAGIC;
- lock->owner = SPINLOCK_OWNER_INIT;
- lock->owner_cpu = -1;
-}
-
-EXPORT_SYMBOL(__raw_spin_lock_init);
-
-void __rwlock_init(rwlock_t *lock, const char *name,
- struct lock_class_key *key)
-{
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
- /*
- * Make sure we are not reinitializing a held lock:
- */
- debug_check_no_locks_freed((void *)lock, sizeof(*lock));
- lockdep_init_map(&lock->dep_map, name, key, 0);
-#endif
- lock->raw_lock = (arch_rwlock_t) __ARCH_RW_LOCK_UNLOCKED;
- lock->magic = RWLOCK_MAGIC;
- lock->owner = SPINLOCK_OWNER_INIT;
- lock->owner_cpu = -1;
-}
-
-EXPORT_SYMBOL(__rwlock_init);
-
-static void spin_dump(raw_spinlock_t *lock, const char *msg)
-{
- struct task_struct *owner = NULL;
-
- if (lock->owner && lock->owner != SPINLOCK_OWNER_INIT)
- owner = lock->owner;
- printk(KERN_EMERG "BUG: spinlock %s on CPU#%d, %s/%d\n",
- msg, raw_smp_processor_id(),
- current->comm, task_pid_nr(current));
- printk(KERN_EMERG " lock: %pS, .magic: %08x, .owner: %s/%d, "
- ".owner_cpu: %d\n",
- lock, lock->magic,
- owner ? owner->comm : "<none>",
- owner ? task_pid_nr(owner) : -1,
- lock->owner_cpu);
- dump_stack();
-}
-
-static void spin_bug(raw_spinlock_t *lock, const char *msg)
-{
- if (!debug_locks_off())
- return;
-
- spin_dump(lock, msg);
-}
-
-#define SPIN_BUG_ON(cond, lock, msg) if (unlikely(cond)) spin_bug(lock, msg)
-
-static inline void
-debug_spin_lock_before(raw_spinlock_t *lock)
-{
- SPIN_BUG_ON(lock->magic != SPINLOCK_MAGIC, lock, "bad magic");
- SPIN_BUG_ON(lock->owner == current, lock, "recursion");
- SPIN_BUG_ON(lock->owner_cpu == raw_smp_processor_id(),
- lock, "cpu recursion");
-}
-
-static inline void debug_spin_lock_after(raw_spinlock_t *lock)
-{
- lock->owner_cpu = raw_smp_processor_id();
- lock->owner = current;
-}
-
-static inline void debug_spin_unlock(raw_spinlock_t *lock)
-{
- SPIN_BUG_ON(lock->magic != SPINLOCK_MAGIC, lock, "bad magic");
- SPIN_BUG_ON(!raw_spin_is_locked(lock), lock, "already unlocked");
- SPIN_BUG_ON(lock->owner != current, lock, "wrong owner");
- SPIN_BUG_ON(lock->owner_cpu != raw_smp_processor_id(),
- lock, "wrong CPU");
- lock->owner = SPINLOCK_OWNER_INIT;
- lock->owner_cpu = -1;
-}
-
-static void __spin_lock_debug(raw_spinlock_t *lock)
-{
- u64 i;
- u64 loops = loops_per_jiffy * HZ;
-
- for (i = 0; i < loops; i++) {
- if (arch_spin_trylock(&lock->raw_lock))
- return;
- __delay(1);
- }
- /* lockup suspected: */
- spin_dump(lock, "lockup suspected");
-#ifdef CONFIG_SMP
- trigger_all_cpu_backtrace();
-#endif
-
- /*
- * The trylock above was causing a livelock. Give the lower level arch
- * specific lock code a chance to acquire the lock. We have already
- * printed a warning/backtrace at this point. The non-debug arch
- * specific code might actually succeed in acquiring the lock. If it is
- * not successful, the end-result is the same - there is no forward
- * progress.
- */
- arch_spin_lock(&lock->raw_lock);
-}
-
-void do_raw_spin_lock(raw_spinlock_t *lock)
-{
- debug_spin_lock_before(lock);
- if (unlikely(!arch_spin_trylock(&lock->raw_lock)))
- __spin_lock_debug(lock);
- debug_spin_lock_after(lock);
-}
-
-int do_raw_spin_trylock(raw_spinlock_t *lock)
-{
- int ret = arch_spin_trylock(&lock->raw_lock);
-
- if (ret)
- debug_spin_lock_after(lock);
-#ifndef CONFIG_SMP
- /*
- * Must not happen on UP:
- */
- SPIN_BUG_ON(!ret, lock, "trylock failure on UP");
-#endif
- return ret;
-}
-
-void do_raw_spin_unlock(raw_spinlock_t *lock)
-{
- debug_spin_unlock(lock);
- arch_spin_unlock(&lock->raw_lock);
-}
-
-static void rwlock_bug(rwlock_t *lock, const char *msg)
-{
- if (!debug_locks_off())
- return;
-
- printk(KERN_EMERG "BUG: rwlock %s on CPU#%d, %s/%d, %p\n",
- msg, raw_smp_processor_id(), current->comm,
- task_pid_nr(current), lock);
- dump_stack();
-}
-
-#define RWLOCK_BUG_ON(cond, lock, msg) if (unlikely(cond)) rwlock_bug(lock, msg)
-
-#if 0 /* __write_lock_debug() can lock up - maybe this can too? */
-static void __read_lock_debug(rwlock_t *lock)
-{
- u64 i;
- u64 loops = loops_per_jiffy * HZ;
- int print_once = 1;
-
- for (;;) {
- for (i = 0; i < loops; i++) {
- if (arch_read_trylock(&lock->raw_lock))
- return;
- __delay(1);
- }
- /* lockup suspected: */
- if (print_once) {
- print_once = 0;
- printk(KERN_EMERG "BUG: read-lock lockup on CPU#%d, "
- "%s/%d, %p\n",
- raw_smp_processor_id(), current->comm,
- current->pid, lock);
- dump_stack();
- }
- }
-}
-#endif
-
-void do_raw_read_lock(rwlock_t *lock)
-{
- RWLOCK_BUG_ON(lock->magic != RWLOCK_MAGIC, lock, "bad magic");
- arch_read_lock(&lock->raw_lock);
-}
-
-int do_raw_read_trylock(rwlock_t *lock)
-{
- int ret = arch_read_trylock(&lock->raw_lock);
-
-#ifndef CONFIG_SMP
- /*
- * Must not happen on UP:
- */
- RWLOCK_BUG_ON(!ret, lock, "trylock failure on UP");
-#endif
- return ret;
-}
-
-void do_raw_read_unlock(rwlock_t *lock)
-{
- RWLOCK_BUG_ON(lock->magic != RWLOCK_MAGIC, lock, "bad magic");
- arch_read_unlock(&lock->raw_lock);
-}
-
-static inline void debug_write_lock_before(rwlock_t *lock)
-{
- RWLOCK_BUG_ON(lock->magic != RWLOCK_MAGIC, lock, "bad magic");
- RWLOCK_BUG_ON(lock->owner == current, lock, "recursion");
- RWLOCK_BUG_ON(lock->owner_cpu == raw_smp_processor_id(),
- lock, "cpu recursion");
-}
-
-static inline void debug_write_lock_after(rwlock_t *lock)
-{
- lock->owner_cpu = raw_smp_processor_id();
- lock->owner = current;
-}
-
-static inline void debug_write_unlock(rwlock_t *lock)
-{
- RWLOCK_BUG_ON(lock->magic != RWLOCK_MAGIC, lock, "bad magic");
- RWLOCK_BUG_ON(lock->owner != current, lock, "wrong owner");
- RWLOCK_BUG_ON(lock->owner_cpu != raw_smp_processor_id(),
- lock, "wrong CPU");
- lock->owner = SPINLOCK_OWNER_INIT;
- lock->owner_cpu = -1;
-}
-
-#if 0 /* This can cause lockups */
-static void __write_lock_debug(rwlock_t *lock)
-{
- u64 i;
- u64 loops = loops_per_jiffy * HZ;
- int print_once = 1;
-
- for (;;) {
- for (i = 0; i < loops; i++) {
- if (arch_write_trylock(&lock->raw_lock))
- return;
- __delay(1);
- }
- /* lockup suspected: */
- if (print_once) {
- print_once = 0;
- printk(KERN_EMERG "BUG: write-lock lockup on CPU#%d, "
- "%s/%d, %p\n",
- raw_smp_processor_id(), current->comm,
- current->pid, lock);
- dump_stack();
- }
- }
-}
-#endif
-
-void do_raw_write_lock(rwlock_t *lock)
-{
- debug_write_lock_before(lock);
- arch_write_lock(&lock->raw_lock);
- debug_write_lock_after(lock);
-}
-
-int do_raw_write_trylock(rwlock_t *lock)
-{
- int ret = arch_write_trylock(&lock->raw_lock);
-
- if (ret)
- debug_write_lock_after(lock);
-#ifndef CONFIG_SMP
- /*
- * Must not happen on UP:
- */
- RWLOCK_BUG_ON(!ret, lock, "trylock failure on UP");
-#endif
- return ret;
-}
-
-void do_raw_write_unlock(rwlock_t *lock)
-{
- debug_write_unlock(lock);
- arch_write_unlock(&lock->raw_lock);
-}
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