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authorIngo Molnar <mingo@elte.hu>2005-09-10 11:25:56 +0400
committerLinus Torvalds <torvalds@g5.osdl.org>2005-09-10 21:06:21 +0400
commitfb1c8f93d869b34cacb8b8932e2b83d96a19d720 (patch)
treea006d078aa02e421a7dc4793c335308204859d36 /include/linux
parent4327edf6b8a7ac7dce144313947995538842d8fd (diff)
downloadlinux-fb1c8f93d869b34cacb8b8932e2b83d96a19d720.tar.xz
[PATCH] spinlock consolidation
This patch (written by me and also containing many suggestions of Arjan van de Ven) does a major cleanup of the spinlock code. It does the following things: - consolidates and enhances the spinlock/rwlock debugging code - simplifies the asm/spinlock.h files - encapsulates the raw spinlock type and moves generic spinlock features (such as ->break_lock) into the generic code. - cleans up the spinlock code hierarchy to get rid of the spaghetti. Most notably there's now only a single variant of the debugging code, located in lib/spinlock_debug.c. (previously we had one SMP debugging variant per architecture, plus a separate generic one for UP builds) Also, i've enhanced the rwlock debugging facility, it will now track write-owners. There is new spinlock-owner/CPU-tracking on SMP builds too. All locks have lockup detection now, which will work for both soft and hard spin/rwlock lockups. The arch-level include files now only contain the minimally necessary subset of the spinlock code - all the rest that can be generalized now lives in the generic headers: include/asm-i386/spinlock_types.h | 16 include/asm-x86_64/spinlock_types.h | 16 I have also split up the various spinlock variants into separate files, making it easier to see which does what. The new layout is: SMP | UP ----------------------------|----------------------------------- asm/spinlock_types_smp.h | linux/spinlock_types_up.h linux/spinlock_types.h | linux/spinlock_types.h asm/spinlock_smp.h | linux/spinlock_up.h linux/spinlock_api_smp.h | linux/spinlock_api_up.h linux/spinlock.h | linux/spinlock.h /* * here's the role of the various spinlock/rwlock related include files: * * on SMP builds: * * asm/spinlock_types.h: contains the raw_spinlock_t/raw_rwlock_t and the * initializers * * linux/spinlock_types.h: * defines the generic type and initializers * * asm/spinlock.h: contains the __raw_spin_*()/etc. lowlevel * implementations, mostly inline assembly code * * (also included on UP-debug builds:) * * linux/spinlock_api_smp.h: * contains the prototypes for the _spin_*() APIs. * * linux/spinlock.h: builds the final spin_*() APIs. * * on UP builds: * * linux/spinlock_type_up.h: * contains the generic, simplified UP spinlock type. * (which is an empty structure on non-debug builds) * * linux/spinlock_types.h: * defines the generic type and initializers * * linux/spinlock_up.h: * contains the __raw_spin_*()/etc. version of UP * builds. (which are NOPs on non-debug, non-preempt * builds) * * (included on UP-non-debug builds:) * * linux/spinlock_api_up.h: * builds the _spin_*() APIs. * * linux/spinlock.h: builds the final spin_*() APIs. */ All SMP and UP architectures are converted by this patch. arm, i386, ia64, ppc, ppc64, s390/s390x, x64 was build-tested via crosscompilers. m32r, mips, sh, sparc, have not been tested yet, but should be mostly fine. From: Grant Grundler <grundler@parisc-linux.org> Booted and lightly tested on a500-44 (64-bit, SMP kernel, dual CPU). Builds 32-bit SMP kernel (not booted or tested). I did not try to build non-SMP kernels. That should be trivial to fix up later if necessary. I converted bit ops atomic_hash lock to raw_spinlock_t. Doing so avoids some ugly nesting of linux/*.h and asm/*.h files. Those particular locks are well tested and contained entirely inside arch specific code. I do NOT expect any new issues to arise with them. If someone does ever need to use debug/metrics with them, then they will need to unravel this hairball between spinlocks, atomic ops, and bit ops that exist only because parisc has exactly one atomic instruction: LDCW (load and clear word). From: "Luck, Tony" <tony.luck@intel.com> ia64 fix Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjanv@infradead.org> Signed-off-by: Grant Grundler <grundler@parisc-linux.org> Cc: Matthew Wilcox <willy@debian.org> Signed-off-by: Hirokazu Takata <takata@linux-m32r.org> Signed-off-by: Mikael Pettersson <mikpe@csd.uu.se> Signed-off-by: Benoit Boissinot <benoit.boissinot@ens-lyon.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'include/linux')
-rw-r--r--include/linux/bit_spinlock.h77
-rw-r--r--include/linux/jbd.h1
-rw-r--r--include/linux/spinlock.h627
-rw-r--r--include/linux/spinlock_api_smp.h57
-rw-r--r--include/linux/spinlock_api_up.h80
-rw-r--r--include/linux/spinlock_types.h67
-rw-r--r--include/linux/spinlock_types_up.h51
-rw-r--r--include/linux/spinlock_up.h74
8 files changed, 532 insertions, 502 deletions
diff --git a/include/linux/bit_spinlock.h b/include/linux/bit_spinlock.h
new file mode 100644
index 000000000000..6b20af0bbb79
--- /dev/null
+++ b/include/linux/bit_spinlock.h
@@ -0,0 +1,77 @@
+#ifndef __LINUX_BIT_SPINLOCK_H
+#define __LINUX_BIT_SPINLOCK_H
+
+/*
+ * bit-based spin_lock()
+ *
+ * Don't use this unless you really need to: spin_lock() and spin_unlock()
+ * are significantly faster.
+ */
+static inline void bit_spin_lock(int bitnum, unsigned long *addr)
+{
+ /*
+ * Assuming the lock is uncontended, this never enters
+ * the body of the outer loop. If it is contended, then
+ * within the inner loop a non-atomic test is used to
+ * busywait with less bus contention for a good time to
+ * attempt to acquire the lock bit.
+ */
+ preempt_disable();
+#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK)
+ while (test_and_set_bit(bitnum, addr)) {
+ while (test_bit(bitnum, addr)) {
+ preempt_enable();
+ cpu_relax();
+ preempt_disable();
+ }
+ }
+#endif
+ __acquire(bitlock);
+}
+
+/*
+ * Return true if it was acquired
+ */
+static inline int bit_spin_trylock(int bitnum, unsigned long *addr)
+{
+ preempt_disable();
+#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK)
+ if (test_and_set_bit(bitnum, addr)) {
+ preempt_enable();
+ return 0;
+ }
+#endif
+ __acquire(bitlock);
+ return 1;
+}
+
+/*
+ * bit-based spin_unlock()
+ */
+static inline void bit_spin_unlock(int bitnum, unsigned long *addr)
+{
+#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK)
+ BUG_ON(!test_bit(bitnum, addr));
+ smp_mb__before_clear_bit();
+ clear_bit(bitnum, addr);
+#endif
+ preempt_enable();
+ __release(bitlock);
+}
+
+/*
+ * Return true if the lock is held.
+ */
+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
+ return preempt_count();
+#else
+ return 1;
+#endif
+}
+
+#endif /* __LINUX_BIT_SPINLOCK_H */
+
diff --git a/include/linux/jbd.h b/include/linux/jbd.h
index 84321a4cac93..de097269bd7f 100644
--- a/include/linux/jbd.h
+++ b/include/linux/jbd.h
@@ -28,6 +28,7 @@
#include <linux/buffer_head.h>
#include <linux/journal-head.h>
#include <linux/stddef.h>
+#include <linux/bit_spinlock.h>
#include <asm/semaphore.h>
#endif
diff --git a/include/linux/spinlock.h b/include/linux/spinlock.h
index d6ba068719b6..cdc99a27840d 100644
--- a/include/linux/spinlock.h
+++ b/include/linux/spinlock.h
@@ -2,7 +2,48 @@
#define __LINUX_SPINLOCK_H
/*
- * include/linux/spinlock.h - generic locking declarations
+ * include/linux/spinlock.h - generic spinlock/rwlock declarations
+ *
+ * here's the role of the various spinlock/rwlock related include files:
+ *
+ * on SMP builds:
+ *
+ * asm/spinlock_types.h: contains the raw_spinlock_t/raw_rwlock_t and the
+ * initializers
+ *
+ * linux/spinlock_types.h:
+ * defines the generic type and initializers
+ *
+ * asm/spinlock.h: contains the __raw_spin_*()/etc. lowlevel
+ * implementations, mostly inline assembly code
+ *
+ * (also included on UP-debug builds:)
+ *
+ * linux/spinlock_api_smp.h:
+ * contains the prototypes for the _spin_*() APIs.
+ *
+ * linux/spinlock.h: builds the final spin_*() APIs.
+ *
+ * on UP builds:
+ *
+ * linux/spinlock_type_up.h:
+ * contains the generic, simplified UP spinlock type.
+ * (which is an empty structure on non-debug builds)
+ *
+ * linux/spinlock_types.h:
+ * defines the generic type and initializers
+ *
+ * linux/spinlock_up.h:
+ * contains the __raw_spin_*()/etc. version of UP
+ * builds. (which are NOPs on non-debug, non-preempt
+ * builds)
+ *
+ * (included on UP-non-debug builds:)
+ *
+ * linux/spinlock_api_up.h:
+ * builds the _spin_*() APIs.
+ *
+ * linux/spinlock.h: builds the final spin_*() APIs.
*/
#include <linux/config.h>
@@ -13,7 +54,6 @@
#include <linux/kernel.h>
#include <linux/stringify.h>
-#include <asm/processor.h> /* for cpu relax */
#include <asm/system.h>
/*
@@ -35,423 +75,84 @@
#define __lockfunc fastcall __attribute__((section(".spinlock.text")))
/*
- * If CONFIG_SMP is set, pull in the _raw_* definitions
+ * Pull the raw_spinlock_t and raw_rwlock_t definitions:
*/
-#ifdef CONFIG_SMP
-
-#define assert_spin_locked(x) BUG_ON(!spin_is_locked(x))
-#include <asm/spinlock.h>
-
-int __lockfunc _spin_trylock(spinlock_t *lock);
-int __lockfunc _read_trylock(rwlock_t *lock);
-int __lockfunc _write_trylock(rwlock_t *lock);
-
-void __lockfunc _spin_lock(spinlock_t *lock) __acquires(spinlock_t);
-void __lockfunc _read_lock(rwlock_t *lock) __acquires(rwlock_t);
-void __lockfunc _write_lock(rwlock_t *lock) __acquires(rwlock_t);
-
-void __lockfunc _spin_unlock(spinlock_t *lock) __releases(spinlock_t);
-void __lockfunc _read_unlock(rwlock_t *lock) __releases(rwlock_t);
-void __lockfunc _write_unlock(rwlock_t *lock) __releases(rwlock_t);
-
-unsigned long __lockfunc _spin_lock_irqsave(spinlock_t *lock) __acquires(spinlock_t);
-unsigned long __lockfunc _read_lock_irqsave(rwlock_t *lock) __acquires(rwlock_t);
-unsigned long __lockfunc _write_lock_irqsave(rwlock_t *lock) __acquires(rwlock_t);
-
-void __lockfunc _spin_lock_irq(spinlock_t *lock) __acquires(spinlock_t);
-void __lockfunc _spin_lock_bh(spinlock_t *lock) __acquires(spinlock_t);
-void __lockfunc _read_lock_irq(rwlock_t *lock) __acquires(rwlock_t);
-void __lockfunc _read_lock_bh(rwlock_t *lock) __acquires(rwlock_t);
-void __lockfunc _write_lock_irq(rwlock_t *lock) __acquires(rwlock_t);
-void __lockfunc _write_lock_bh(rwlock_t *lock) __acquires(rwlock_t);
-
-void __lockfunc _spin_unlock_irqrestore(spinlock_t *lock, unsigned long flags) __releases(spinlock_t);
-void __lockfunc _spin_unlock_irq(spinlock_t *lock) __releases(spinlock_t);
-void __lockfunc _spin_unlock_bh(spinlock_t *lock) __releases(spinlock_t);
-void __lockfunc _read_unlock_irqrestore(rwlock_t *lock, unsigned long flags) __releases(rwlock_t);
-void __lockfunc _read_unlock_irq(rwlock_t *lock) __releases(rwlock_t);
-void __lockfunc _read_unlock_bh(rwlock_t *lock) __releases(rwlock_t);
-void __lockfunc _write_unlock_irqrestore(rwlock_t *lock, unsigned long flags) __releases(rwlock_t);
-void __lockfunc _write_unlock_irq(rwlock_t *lock) __releases(rwlock_t);
-void __lockfunc _write_unlock_bh(rwlock_t *lock) __releases(rwlock_t);
-
-int __lockfunc _spin_trylock_bh(spinlock_t *lock);
-int __lockfunc generic_raw_read_trylock(rwlock_t *lock);
-int in_lock_functions(unsigned long addr);
-
-#else
+#include <linux/spinlock_types.h>
-#define in_lock_functions(ADDR) 0
+extern int __lockfunc generic__raw_read_trylock(raw_rwlock_t *lock);
-#if !defined(CONFIG_PREEMPT) && !defined(CONFIG_DEBUG_SPINLOCK)
-# define _atomic_dec_and_lock(atomic,lock) atomic_dec_and_test(atomic)
-# define ATOMIC_DEC_AND_LOCK
-#endif
-
-#ifdef CONFIG_DEBUG_SPINLOCK
-
-#define SPINLOCK_MAGIC 0x1D244B3C
-typedef struct {
- unsigned long magic;
- volatile unsigned long lock;
- volatile unsigned int babble;
- const char *module;
- char *owner;
- int oline;
-} spinlock_t;
-#define SPIN_LOCK_UNLOCKED (spinlock_t) { SPINLOCK_MAGIC, 0, 10, __FILE__ , NULL, 0}
-
-#define spin_lock_init(x) \
- do { \
- (x)->magic = SPINLOCK_MAGIC; \
- (x)->lock = 0; \
- (x)->babble = 5; \
- (x)->module = __FILE__; \
- (x)->owner = NULL; \
- (x)->oline = 0; \
- } while (0)
-
-#define CHECK_LOCK(x) \
- do { \
- if ((x)->magic != SPINLOCK_MAGIC) { \
- printk(KERN_ERR "%s:%d: spin_is_locked on uninitialized spinlock %p.\n", \
- __FILE__, __LINE__, (x)); \
- } \
- } while(0)
-
-#define _raw_spin_lock(x) \
- do { \
- CHECK_LOCK(x); \
- if ((x)->lock&&(x)->babble) { \
- (x)->babble--; \
- printk("%s:%d: spin_lock(%s:%p) already locked by %s/%d\n", \
- __FILE__,__LINE__, (x)->module, \
- (x), (x)->owner, (x)->oline); \
- } \
- (x)->lock = 1; \
- (x)->owner = __FILE__; \
- (x)->oline = __LINE__; \
- } while (0)
-
-/* without debugging, spin_is_locked on UP always says
- * FALSE. --> printk if already locked. */
-#define spin_is_locked(x) \
- ({ \
- CHECK_LOCK(x); \
- if ((x)->lock&&(x)->babble) { \
- (x)->babble--; \
- printk("%s:%d: spin_is_locked(%s:%p) already locked by %s/%d\n", \
- __FILE__,__LINE__, (x)->module, \
- (x), (x)->owner, (x)->oline); \
- } \
- 0; \
- })
-
-/* with debugging, assert_spin_locked() on UP does check
- * the lock value properly */
-#define assert_spin_locked(x) \
- ({ \
- CHECK_LOCK(x); \
- BUG_ON(!(x)->lock); \
- })
-
-/* without debugging, spin_trylock on UP always says
- * TRUE. --> printk if already locked. */
-#define _raw_spin_trylock(x) \
- ({ \
- CHECK_LOCK(x); \
- if ((x)->lock&&(x)->babble) { \
- (x)->babble--; \
- printk("%s:%d: spin_trylock(%s:%p) already locked by %s/%d\n", \
- __FILE__,__LINE__, (x)->module, \
- (x), (x)->owner, (x)->oline); \
- } \
- (x)->lock = 1; \
- (x)->owner = __FILE__; \
- (x)->oline = __LINE__; \
- 1; \
- })
-
-#define spin_unlock_wait(x) \
- do { \
- CHECK_LOCK(x); \
- if ((x)->lock&&(x)->babble) { \
- (x)->babble--; \
- printk("%s:%d: spin_unlock_wait(%s:%p) owned by %s/%d\n", \
- __FILE__,__LINE__, (x)->module, (x), \
- (x)->owner, (x)->oline); \
- }\
- } while (0)
-
-#define _raw_spin_unlock(x) \
- do { \
- CHECK_LOCK(x); \
- if (!(x)->lock&&(x)->babble) { \
- (x)->babble--; \
- printk("%s:%d: spin_unlock(%s:%p) not locked\n", \
- __FILE__,__LINE__, (x)->module, (x));\
- } \
- (x)->lock = 0; \
- } while (0)
-#else
/*
- * gcc versions before ~2.95 have a nasty bug with empty initializers.
+ * Pull the __raw*() functions/declarations (UP-nondebug doesnt need them):
*/
-#if (__GNUC__ > 2)
- typedef struct { } spinlock_t;
- #define SPIN_LOCK_UNLOCKED (spinlock_t) { }
+#if defined(CONFIG_SMP)
+# include <asm/spinlock.h>
#else
- typedef struct { int gcc_is_buggy; } spinlock_t;
- #define SPIN_LOCK_UNLOCKED (spinlock_t) { 0 }
+# include <linux/spinlock_up.h>
#endif
+#define spin_lock_init(lock) do { *(lock) = SPIN_LOCK_UNLOCKED; } while (0)
+#define rwlock_init(lock) do { *(lock) = RW_LOCK_UNLOCKED; } while (0)
+
+#define spin_is_locked(lock) __raw_spin_is_locked(&(lock)->raw_lock)
+
+/**
+ * spin_unlock_wait - wait until the spinlock gets unlocked
+ * @lock: the spinlock in question.
+ */
+#define spin_unlock_wait(lock) __raw_spin_unlock_wait(&(lock)->raw_lock)
+
/*
- * If CONFIG_SMP is unset, declare the _raw_* definitions as nops
+ * Pull the _spin_*()/_read_*()/_write_*() functions/declarations:
*/
-#define spin_lock_init(lock) do { (void)(lock); } while(0)
-#define _raw_spin_lock(lock) do { (void)(lock); } while(0)
-#define spin_is_locked(lock) ((void)(lock), 0)
-#define assert_spin_locked(lock) do { (void)(lock); } while(0)
-#define _raw_spin_trylock(lock) (((void)(lock), 1))
-#define spin_unlock_wait(lock) (void)(lock)
-#define _raw_spin_unlock(lock) do { (void)(lock); } while(0)
-#endif /* CONFIG_DEBUG_SPINLOCK */
-
-/* RW spinlocks: No debug version */
-
-#if (__GNUC__ > 2)
- typedef struct { } rwlock_t;
- #define RW_LOCK_UNLOCKED (rwlock_t) { }
+#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK)
+# include <linux/spinlock_api_smp.h>
#else
- typedef struct { int gcc_is_buggy; } rwlock_t;
- #define RW_LOCK_UNLOCKED (rwlock_t) { 0 }
+# include <linux/spinlock_api_up.h>
#endif
-#define rwlock_init(lock) do { (void)(lock); } while(0)
-#define _raw_read_lock(lock) do { (void)(lock); } while(0)
-#define _raw_read_unlock(lock) do { (void)(lock); } while(0)
-#define _raw_write_lock(lock) do { (void)(lock); } while(0)
-#define _raw_write_unlock(lock) do { (void)(lock); } while(0)
-#define read_can_lock(lock) (((void)(lock), 1))
-#define write_can_lock(lock) (((void)(lock), 1))
-#define _raw_read_trylock(lock) ({ (void)(lock); (1); })
-#define _raw_write_trylock(lock) ({ (void)(lock); (1); })
-
-#define _spin_trylock(lock) ({preempt_disable(); _raw_spin_trylock(lock) ? \
- 1 : ({preempt_enable(); 0;});})
-
-#define _read_trylock(lock) ({preempt_disable();_raw_read_trylock(lock) ? \
- 1 : ({preempt_enable(); 0;});})
-
-#define _write_trylock(lock) ({preempt_disable(); _raw_write_trylock(lock) ? \
- 1 : ({preempt_enable(); 0;});})
-
-#define _spin_trylock_bh(lock) ({preempt_disable(); local_bh_disable(); \
- _raw_spin_trylock(lock) ? \
- 1 : ({preempt_enable_no_resched(); local_bh_enable(); 0;});})
-
-#define _spin_lock(lock) \
-do { \
- preempt_disable(); \
- _raw_spin_lock(lock); \
- __acquire(lock); \
-} while(0)
-
-#define _write_lock(lock) \
-do { \
- preempt_disable(); \
- _raw_write_lock(lock); \
- __acquire(lock); \
-} while(0)
-
-#define _read_lock(lock) \
-do { \
- preempt_disable(); \
- _raw_read_lock(lock); \
- __acquire(lock); \
-} while(0)
-
-#define _spin_unlock(lock) \
-do { \
- _raw_spin_unlock(lock); \
- preempt_enable(); \
- __release(lock); \
-} while (0)
-
-#define _write_unlock(lock) \
-do { \
- _raw_write_unlock(lock); \
- preempt_enable(); \
- __release(lock); \
-} while(0)
-
-#define _read_unlock(lock) \
-do { \
- _raw_read_unlock(lock); \
- preempt_enable(); \
- __release(lock); \
-} while(0)
-
-#define _spin_lock_irqsave(lock, flags) \
-do { \
- local_irq_save(flags); \
- preempt_disable(); \
- _raw_spin_lock(lock); \
- __acquire(lock); \
-} while (0)
-
-#define _spin_lock_irq(lock) \
-do { \
- local_irq_disable(); \
- preempt_disable(); \
- _raw_spin_lock(lock); \
- __acquire(lock); \
-} while (0)
-
-#define _spin_lock_bh(lock) \
-do { \
- local_bh_disable(); \
- preempt_disable(); \
- _raw_spin_lock(lock); \
- __acquire(lock); \
-} while (0)
-
-#define _read_lock_irqsave(lock, flags) \
-do { \
- local_irq_save(flags); \
- preempt_disable(); \
- _raw_read_lock(lock); \
- __acquire(lock); \
-} while (0)
-
-#define _read_lock_irq(lock) \
-do { \
- local_irq_disable(); \
- preempt_disable(); \
- _raw_read_lock(lock); \
- __acquire(lock); \
-} while (0)
-
-#define _read_lock_bh(lock) \
-do { \
- local_bh_disable(); \
- preempt_disable(); \
- _raw_read_lock(lock); \
- __acquire(lock); \
-} while (0)
-
-#define _write_lock_irqsave(lock, flags) \
-do { \
- local_irq_save(flags); \
- preempt_disable(); \
- _raw_write_lock(lock); \
- __acquire(lock); \
-} while (0)
+#ifdef CONFIG_DEBUG_SPINLOCK
+ extern void _raw_spin_lock(spinlock_t *lock);
+#define _raw_spin_lock_flags(lock, flags) _raw_spin_lock(lock)
+ extern int _raw_spin_trylock(spinlock_t *lock);
+ extern void _raw_spin_unlock(spinlock_t *lock);
+
+ extern void _raw_read_lock(rwlock_t *lock);
+ extern int _raw_read_trylock(rwlock_t *lock);
+ extern void _raw_read_unlock(rwlock_t *lock);
+ extern void _raw_write_lock(rwlock_t *lock);
+ extern int _raw_write_trylock(rwlock_t *lock);
+ extern void _raw_write_unlock(rwlock_t *lock);
+#else
+# define _raw_spin_unlock(lock) __raw_spin_unlock(&(lock)->raw_lock)
+# define _raw_spin_trylock(lock) __raw_spin_trylock(&(lock)->raw_lock)
+# define _raw_spin_lock(lock) __raw_spin_lock(&(lock)->raw_lock)
+# define _raw_spin_lock_flags(lock, flags) \
+ __raw_spin_lock_flags(&(lock)->raw_lock, *(flags))
+# define _raw_read_lock(rwlock) __raw_read_lock(&(rwlock)->raw_lock)
+# define _raw_write_lock(rwlock) __raw_write_lock(&(rwlock)->raw_lock)
+# define _raw_read_unlock(rwlock) __raw_read_unlock(&(rwlock)->raw_lock)
+# define _raw_write_unlock(rwlock) __raw_write_unlock(&(rwlock)->raw_lock)
+# define _raw_read_trylock(rwlock) __raw_read_trylock(&(rwlock)->raw_lock)
+# define _raw_write_trylock(rwlock) __raw_write_trylock(&(rwlock)->raw_lock)
+#endif
-#define _write_lock_irq(lock) \
-do { \
- local_irq_disable(); \
- preempt_disable(); \
- _raw_write_lock(lock); \
- __acquire(lock); \
-} while (0)
-
-#define _write_lock_bh(lock) \
-do { \
- local_bh_disable(); \
- preempt_disable(); \
- _raw_write_lock(lock); \
- __acquire(lock); \
-} while (0)
-
-#define _spin_unlock_irqrestore(lock, flags) \
-do { \
- _raw_spin_unlock(lock); \
- local_irq_restore(flags); \
- preempt_enable(); \
- __release(lock); \
-} while (0)
-
-#define _spin_unlock_irq(lock) \
-do { \
- _raw_spin_unlock(lock); \
- local_irq_enable(); \
- preempt_enable(); \
- __release(lock); \
-} while (0)
-
-#define _spin_unlock_bh(lock) \
-do { \
- _raw_spin_unlock(lock); \
- preempt_enable_no_resched(); \
- local_bh_enable(); \
- __release(lock); \
-} while (0)
-
-#define _write_unlock_bh(lock) \
-do { \
- _raw_write_unlock(lock); \
- preempt_enable_no_resched(); \
- local_bh_enable(); \
- __release(lock); \
-} while (0)
-
-#define _read_unlock_irqrestore(lock, flags) \
-do { \
- _raw_read_unlock(lock); \
- local_irq_restore(flags); \
- preempt_enable(); \
- __release(lock); \
-} while (0)
-
-#define _write_unlock_irqrestore(lock, flags) \
-do { \
- _raw_write_unlock(lock); \
- local_irq_restore(flags); \
- preempt_enable(); \
- __release(lock); \
-} while (0)
-
-#define _read_unlock_irq(lock) \
-do { \
- _raw_read_unlock(lock); \
- local_irq_enable(); \
- preempt_enable(); \
- __release(lock); \
-} while (0)
-
-#define _read_unlock_bh(lock) \
-do { \
- _raw_read_unlock(lock); \
- preempt_enable_no_resched(); \
- local_bh_enable(); \
- __release(lock); \
-} while (0)
-
-#define _write_unlock_irq(lock) \
-do { \
- _raw_write_unlock(lock); \
- local_irq_enable(); \
- preempt_enable(); \
- __release(lock); \
-} while (0)
-
-#endif /* !SMP */
+#define read_can_lock(rwlock) __raw_read_can_lock(&(rwlock)->raw_lock)
+#define write_can_lock(rwlock) __raw_write_can_lock(&(rwlock)->raw_lock)
/*
* Define the various spin_lock and rw_lock methods. Note we define these
* regardless of whether CONFIG_SMP or CONFIG_PREEMPT are set. The various
* methods are defined as nops in the case they are not required.
*/
-#define spin_trylock(lock) __cond_lock(_spin_trylock(lock))
-#define read_trylock(lock) __cond_lock(_read_trylock(lock))
-#define write_trylock(lock) __cond_lock(_write_trylock(lock))
+#define spin_trylock(lock) __cond_lock(_spin_trylock(lock))
+#define read_trylock(lock) __cond_lock(_read_trylock(lock))
+#define write_trylock(lock) __cond_lock(_write_trylock(lock))
-#define spin_lock(lock) _spin_lock(lock)
-#define write_lock(lock) _write_lock(lock)
-#define read_lock(lock) _read_lock(lock)
+#define spin_lock(lock) _spin_lock(lock)
+#define write_lock(lock) _write_lock(lock)
+#define read_lock(lock) _read_lock(lock)
-#ifdef CONFIG_SMP
+#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK)
#define spin_lock_irqsave(lock, flags) flags = _spin_lock_irqsave(lock)
#define read_lock_irqsave(lock, flags) flags = _read_lock_irqsave(lock)
#define write_lock_irqsave(lock, flags) flags = _write_lock_irqsave(lock)
@@ -470,137 +171,59 @@ do { \
#define write_lock_irq(lock) _write_lock_irq(lock)
#define write_lock_bh(lock) _write_lock_bh(lock)
-#define spin_unlock(lock) _spin_unlock(lock)
-#define write_unlock(lock) _write_unlock(lock)
-#define read_unlock(lock) _read_unlock(lock)
+#define spin_unlock(lock) _spin_unlock(lock)
+#define write_unlock(lock) _write_unlock(lock)
+#define read_unlock(lock) _read_unlock(lock)
-#define spin_unlock_irqrestore(lock, flags) _spin_unlock_irqrestore(lock, flags)
+#define spin_unlock_irqrestore(lock, flags) \
+ _spin_unlock_irqrestore(lock, flags)
#define spin_unlock_irq(lock) _spin_unlock_irq(lock)
#define spin_unlock_bh(lock) _spin_unlock_bh(lock)
-#define read_unlock_irqrestore(lock, flags) _read_unlock_irqrestore(lock, flags)
-#define read_unlock_irq(lock) _read_unlock_irq(lock)
-#define read_unlock_bh(lock) _read_unlock_bh(lock)
+#define read_unlock_irqrestore(lock, flags) \
+ _read_unlock_irqrestore(lock, flags)
+#define read_unlock_irq(lock) _read_unlock_irq(lock)
+#define read_unlock_bh(lock) _read_unlock_bh(lock)
-#define write_unlock_irqrestore(lock, flags) _write_unlock_irqrestore(lock, flags)
-#define write_unlock_irq(lock) _write_unlock_irq(lock)
-#define write_unlock_bh(lock) _write_unlock_bh(lock)
+#define write_unlock_irqrestore(lock, flags) \
+ _write_unlock_irqrestore(lock, flags)
+#define write_unlock_irq(lock) _write_unlock_irq(lock)
+#define write_unlock_bh(lock) _write_unlock_bh(lock)
-#define spin_trylock_bh(lock) __cond_lock(_spin_trylock_bh(lock))
+#define spin_trylock_bh(lock) __cond_lock(_spin_trylock_bh(lock))
#define spin_trylock_irq(lock) \
({ \
local_irq_disable(); \
_spin_trylock(lock) ? \
- 1 : ({local_irq_enable(); 0; }); \
+ 1 : ({ local_irq_enable(); 0; }); \
})
#define spin_trylock_irqsave(lock, flags) \
({ \
local_irq_save(flags); \
_spin_trylock(lock) ? \
- 1 : ({local_irq_restore(flags); 0;}); \
+ 1 : ({ local_irq_restore(flags); 0; }); \
})
-#ifdef CONFIG_LOCKMETER
-extern void _metered_spin_lock (spinlock_t *lock);
-extern void _metered_spin_unlock (spinlock_t *lock);
-extern int _metered_spin_trylock(spinlock_t *lock);
-extern void _metered_read_lock (rwlock_t *lock);
-extern void _metered_read_unlock (rwlock_t *lock);
-extern void _metered_write_lock (rwlock_t *lock);
-extern void _metered_write_unlock (rwlock_t *lock);
-extern int _metered_read_trylock (rwlock_t *lock);
-extern int _metered_write_trylock(rwlock_t *lock);
-#endif
-
-/* "lock on reference count zero" */
-#ifndef ATOMIC_DEC_AND_LOCK
-#include <asm/atomic.h>
-extern int _atomic_dec_and_lock(atomic_t *atomic, spinlock_t *lock);
-#endif
-
-#define atomic_dec_and_lock(atomic,lock) __cond_lock(_atomic_dec_and_lock(atomic,lock))
-
-/*
- * bit-based spin_lock()
- *
- * Don't use this unless you really need to: spin_lock() and spin_unlock()
- * are significantly faster.
- */
-static inline void bit_spin_lock(int bitnum, unsigned long *addr)
-{
- /*
- * Assuming the lock is uncontended, this never enters
- * the body of the outer loop. If it is contended, then
- * within the inner loop a non-atomic test is used to
- * busywait with less bus contention for a good time to
- * attempt to acquire the lock bit.
- */
- preempt_disable();
-#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK)
- while (test_and_set_bit(bitnum, addr)) {
- while (test_bit(bitnum, addr)) {
- preempt_enable();
- cpu_relax();
- preempt_disable();
- }
- }
-#endif
- __acquire(bitlock);
-}
-
/*
- * Return true if it was acquired
+ * Pull the atomic_t declaration:
+ * (asm-mips/atomic.h needs above definitions)
*/
-static inline int bit_spin_trylock(int bitnum, unsigned long *addr)
-{
- preempt_disable();
-#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK)
- if (test_and_set_bit(bitnum, addr)) {
- preempt_enable();
- return 0;
- }
-#endif
- __acquire(bitlock);
- return 1;
-}
-
-/*
- * bit-based spin_unlock()
- */
-static inline void bit_spin_unlock(int bitnum, unsigned long *addr)
-{
-#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK)
- BUG_ON(!test_bit(bitnum, addr));
- smp_mb__before_clear_bit();
- clear_bit(bitnum, addr);
-#endif
- preempt_enable();
- __release(bitlock);
-}
-
-/*
- * Return true if the lock is held.
+#include <asm/atomic.h>
+/**
+ * atomic_dec_and_lock - lock on reaching reference count zero
+ * @atomic: the atomic counter
+ * @lock: the spinlock in question
*/
-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
- return preempt_count();
-#else
- return 1;
-#endif
-}
-
-#define DEFINE_SPINLOCK(x) spinlock_t x = SPIN_LOCK_UNLOCKED
-#define DEFINE_RWLOCK(x) rwlock_t x = RW_LOCK_UNLOCKED
+extern int _atomic_dec_and_lock(atomic_t *atomic, spinlock_t *lock);
+#define atomic_dec_and_lock(atomic, lock) \
+ __cond_lock(_atomic_dec_and_lock(atomic, lock))
/**
* spin_can_lock - would spin_trylock() succeed?
* @lock: the spinlock in question.
*/
-#define spin_can_lock(lock) (!spin_is_locked(lock))
+#define spin_can_lock(lock) (!spin_is_locked(lock))
#endif /* __LINUX_SPINLOCK_H */
diff --git a/include/linux/spinlock_api_smp.h b/include/linux/spinlock_api_smp.h
new file mode 100644
index 000000000000..78e6989ffb54
--- /dev/null
+++ b/include/linux/spinlock_api_smp.h
@@ -0,0 +1,57 @@
+#ifndef __LINUX_SPINLOCK_API_SMP_H
+#define __LINUX_SPINLOCK_API_SMP_H
+
+#ifndef __LINUX_SPINLOCK_H
+# error "please don't include this file directly"
+#endif
+
+/*
+ * include/linux/spinlock_api_smp.h
+ *
+ * spinlock API declarations on SMP (and debug)
+ * (implemented in kernel/spinlock.c)
+ *
+ * portions Copyright 2005, Red Hat, Inc., Ingo Molnar
+ * Released under the General Public License (GPL).
+ */
+
+int in_lock_functions(unsigned long addr);
+
+#define assert_spin_locked(x) BUG_ON(!spin_is_locked(x))
+
+void __lockfunc _spin_lock(spinlock_t *lock) __acquires(spinlock_t);
+void __lockfunc _read_lock(rwlock_t *lock) __acquires(rwlock_t);
+void __lockfunc _write_lock(rwlock_t *lock) __acquires(rwlock_t);
+void __lockfunc _spin_lock_bh(spinlock_t *lock) __acquires(spinlock_t);
+void __lockfunc _read_lock_bh(rwlock_t *lock) __acquires(rwlock_t);
+void __lockfunc _write_lock_bh(rwlock_t *lock) __acquires(rwlock_t);
+void __lockfunc _spin_lock_irq(spinlock_t *lock) __acquires(spinlock_t);
+void __lockfunc _read_lock_irq(rwlock_t *lock) __acquires(rwlock_t);
+void __lockfunc _write_lock_irq(rwlock_t *lock) __acquires(rwlock_t);
+unsigned long __lockfunc _spin_lock_irqsave(spinlock_t *lock)
+ __acquires(spinlock_t);
+unsigned long __lockfunc _read_lock_irqsave(rwlock_t *lock)
+ __acquires(rwlock_t);
+unsigned long __lockfunc _write_lock_irqsave(rwlock_t *lock)
+ __acquires(rwlock_t);
+int __lockfunc _spin_trylock(spinlock_t *lock);
+int __lockfunc _read_trylock(rwlock_t *lock);
+int __lockfunc _write_trylock(rwlock_t *lock);
+int __lockfunc _spin_trylock_bh(spinlock_t *lock);
+void __lockfunc _spin_unlock(spinlock_t *lock) __releases(spinlock_t);
+void __lockfunc _read_unlock(rwlock_t *lock) __releases(rwlock_t);
+void __lockfunc _write_unlock(rwlock_t *lock) __releases(rwlock_t);
+void __lockfunc _spin_unlock_bh(spinlock_t *lock) __releases(spinlock_t);
+void __lockfunc _read_unlock_bh(rwlock_t *lock) __releases(rwlock_t);
+void __lockfunc _write_unlock_bh(rwlock_t *lock) __releases(rwlock_t);
+void __lockfunc _spin_unlock_irq(spinlock_t *lock) __releases(spinlock_t);
+void __lockfunc _read_unlock_irq(rwlock_t *lock) __releases(rwlock_t);
+void __lockfunc _write_unlock_irq(rwlock_t *lock) __releases(rwlock_t);
+void __lockfunc _spin_unlock_irqrestore(spinlock_t *lock, unsigned long flags)
+ __releases(spinlock_t);
+void __lockfunc _read_unlock_irqrestore(rwlock_t *lock, unsigned long flags)
+ __releases(rwlock_t);
+void __lockfunc _write_unlock_irqrestore(rwlock_t *lock, unsigned long flags)
+ __releases(rwlock_t);
+
+#endif /* __LINUX_SPINLOCK_API_SMP_H */
diff --git a/include/linux/spinlock_api_up.h b/include/linux/spinlock_api_up.h
new file mode 100644
index 000000000000..cd81cee566f4
--- /dev/null
+++ b/include/linux/spinlock_api_up.h
@@ -0,0 +1,80 @@
+#ifndef __LINUX_SPINLOCK_API_UP_H
+#define __LINUX_SPINLOCK_API_UP_H
+
+#ifndef __LINUX_SPINLOCK_H
+# error "please don't include this file directly"
+#endif
+
+/*
+ * include/linux/spinlock_api_up.h
+ *
+ * spinlock API implementation on UP-nondebug (inlined implementation)
+ *
+ * portions Copyright 2005, Red Hat, Inc., Ingo Molnar
+ * Released under the General Public License (GPL).
+ */
+
+#define in_lock_functions(ADDR) 0
+
+#define assert_spin_locked(lock) do { (void)(lock); } while (0)
+
+/*
+ * In the UP-nondebug case there's no real locking going on, so the
+ * only thing we have to do is to keep the preempt counts and irq
+ * flags straight, to supress compiler warnings of unused lock
+ * variables, and to add the proper checker annotations:
+ */
+#define __LOCK(lock) \
+ do { preempt_disable(); __acquire(lock); (void)(lock); } while (0)
+
+#define __LOCK_BH(lock) \
+ do { local_bh_disable(); __LOCK(lock); } while (0)
+
+#define __LOCK_IRQ(lock) \
+ do { local_irq_disable(); __LOCK(lock); } while (0)
+
+#define __LOCK_IRQSAVE(lock, flags) \
+ do { local_irq_save(flags); __LOCK(lock); } while (0)
+
+#define __UNLOCK(lock) \
+ do { preempt_enable(); __release(lock); (void)(lock); } while (0)
+
+#define __UNLOCK_BH(lock) \
+ do { preempt_enable_no_resched(); local_bh_enable(); __release(lock); (void)(lock); } while (0)
+
+#define __UNLOCK_IRQ(lock) \
+ do { local_irq_enable(); __UNLOCK(lock); } while (0)
+
+#define __UNLOCK_IRQRESTORE(lock, flags) \
+ do { local_irq_restore(flags); __UNLOCK(lock); } while (0)
+
+#define _spin_lock(lock) __LOCK(lock)
+#define _read_lock(lock) __LOCK(lock)
+#define _write_lock(lock) __LOCK(lock)
+#define _spin_lock_bh(lock) __LOCK_BH(lock)
+#define _read_lock_bh(lock) __LOCK_BH(lock)
+#define _write_lock_bh(lock) __LOCK_BH(lock)
+#define _spin_lock_irq(lock) __LOCK_IRQ(lock)
+#define _read_lock_irq(lock) __LOCK_IRQ(lock)
+#define _write_lock_irq(lock) __LOCK_IRQ(lock)
+#define _spin_lock_irqsave(lock, flags) __LOCK_IRQSAVE(lock, flags)
+#define _read_lock_irqsave(lock, flags) __LOCK_IRQSAVE(lock, flags)
+#define _write_lock_irqsave(lock, flags) __LOCK_IRQSAVE(lock, flags)
+#define _spin_trylock(lock) ({ __LOCK(lock); 1; })
+#define _read_trylock(lock) ({ __LOCK(lock); 1; })
+#define _write_trylock(lock) ({ __LOCK(lock); 1; })
+#define _spin_trylock_bh(lock) ({ __LOCK_BH(lock); 1; })
+#define _spin_unlock(lock) __UNLOCK(lock)
+#define _read_unlock(lock) __UNLOCK(lock)
+#define _write_unlock(lock) __UNLOCK(lock)
+#define _spin_unlock_bh(lock) __UNLOCK_BH(lock)
+#define _write_unlock_bh(lock) __UNLOCK_BH(lock)
+#define _read_unlock_bh(lock) __UNLOCK_BH(lock)
+#define _spin_unlock_irq(lock) __UNLOCK_IRQ(lock)
+#define _read_unlock_irq(lock) __UNLOCK_IRQ(lock)
+#define _write_unlock_irq(lock) __UNLOCK_IRQ(lock)
+#define _spin_unlock_irqrestore(lock, flags) __UNLOCK_IRQRESTORE(lock, flags)
+#define _read_unlock_irqrestore(lock, flags) __UNLOCK_IRQRESTORE(lock, flags)
+#define _write_unlock_irqrestore(lock, flags) __UNLOCK_IRQRESTORE(lock, flags)
+
+#endif /* __LINUX_SPINLOCK_API_UP_H */
diff --git a/include/linux/spinlock_types.h b/include/linux/spinlock_types.h
new file mode 100644
index 000000000000..9cb51e070390
--- /dev/null
+++ b/include/linux/spinlock_types.h
@@ -0,0 +1,67 @@
+#ifndef __LINUX_SPINLOCK_TYPES_H
+#define __LINUX_SPINLOCK_TYPES_H
+
+/*
+ * include/linux/spinlock_types.h - generic spinlock type definitions
+ * and initializers
+ *
+ * portions Copyright 2005, Red Hat, Inc., Ingo Molnar
+ * Released under the General Public License (GPL).
+ */
+
+#if defined(CONFIG_SMP)
+# include <asm/spinlock_types.h>
+#else
+# include <linux/spinlock_types_up.h>
+#endif
+
+typedef struct {
+ raw_spinlock_t raw_lock;
+#if defined(CONFIG_PREEMPT) && defined(CONFIG_SMP)
+ unsigned int break_lock;
+#endif
+#ifdef CONFIG_DEBUG_SPINLOCK
+ unsigned int magic, owner_cpu;
+ void *owner;
+#endif
+} spinlock_t;
+
+#define SPINLOCK_MAGIC 0xdead4ead
+
+typedef struct {
+ raw_rwlock_t raw_lock;
+#if defined(CONFIG_PREEMPT) && defined(CONFIG_SMP)
+ unsigned int break_lock;
+#endif
+#ifdef CONFIG_DEBUG_SPINLOCK
+ unsigned int magic, owner_cpu;
+ void *owner;
+#endif
+} rwlock_t;
+
+#define RWLOCK_MAGIC 0xdeaf1eed
+
+#define SPINLOCK_OWNER_INIT ((void *)-1L)
+
+#ifdef CONFIG_DEBUG_SPINLOCK
+# define SPIN_LOCK_UNLOCKED \
+ (spinlock_t) { .raw_lock = __RAW_SPIN_LOCK_UNLOCKED, \
+ .magic = SPINLOCK_MAGIC, \
+ .owner = SPINLOCK_OWNER_INIT, \
+ .owner_cpu = -1 }
+#define RW_LOCK_UNLOCKED \
+ (rwlock_t) { .raw_lock = __RAW_RW_LOCK_UNLOCKED, \
+ .magic = RWLOCK_MAGIC, \
+ .owner = SPINLOCK_OWNER_INIT, \
+ .owner_cpu = -1 }
+#else
+# define SPIN_LOCK_UNLOCKED \
+ (spinlock_t) { .raw_lock = __RAW_SPIN_LOCK_UNLOCKED }
+#define RW_LOCK_UNLOCKED \
+ (rwlock_t) { .raw_lock = __RAW_RW_LOCK_UNLOCKED }
+#endif
+
+#define DEFINE_SPINLOCK(x) spinlock_t x = SPIN_LOCK_UNLOCKED
+#define DEFINE_RWLOCK(x) rwlock_t x = RW_LOCK_UNLOCKED
+
+#endif /* __LINUX_SPINLOCK_TYPES_H */
diff --git a/include/linux/spinlock_types_up.h b/include/linux/spinlock_types_up.h
new file mode 100644
index 000000000000..def2d173a8db
--- /dev/null
+++ b/include/linux/spinlock_types_up.h
@@ -0,0 +1,51 @@
+#ifndef __LINUX_SPINLOCK_TYPES_UP_H
+#define __LINUX_SPINLOCK_TYPES_UP_H
+
+#ifndef __LINUX_SPINLOCK_TYPES_H
+# error "please don't include this file directly"
+#endif
+
+/*
+ * include/linux/spinlock_types_up.h - spinlock type definitions for UP
+ *
+ * portions Copyright 2005, Red Hat, Inc., Ingo Molnar
+ * Released under the General Public License (GPL).
+ */
+
+#ifdef CONFIG_DEBUG_SPINLOCK
+
+typedef struct {
+ volatile unsigned int slock;
+} raw_spinlock_t;
+
+#define __RAW_SPIN_LOCK_UNLOCKED { 1 }
+
+#else
+
+/*
+ * All gcc 2.95 versions and early versions of 2.96 have a nasty bug
+ * with empty initializers.
+ */
+#if (__GNUC__ > 2)
+typedef struct { } raw_spinlock_t;
+
+#define __RAW_SPIN_LOCK_UNLOCKED { }
+#else
+typedef struct { int gcc_is_buggy; } raw_spinlock_t;
+#define __RAW_SPIN_LOCK_UNLOCKED (raw_spinlock_t) { 0 }
+#endif
+
+#endif
+
+#if (__GNUC__ > 2)
+typedef struct {
+ /* no debug version on UP */
+} raw_rwlock_t;
+
+#define __RAW_RW_LOCK_UNLOCKED { }
+#else
+typedef struct { int gcc_is_buggy; } raw_rwlock_t;
+#define __RAW_RW_LOCK_UNLOCKED (raw_rwlock_t) { 0 }
+#endif
+
+#endif /* __LINUX_SPINLOCK_TYPES_UP_H */
diff --git a/include/linux/spinlock_up.h b/include/linux/spinlock_up.h
new file mode 100644
index 000000000000..31accf2f0b13
--- /dev/null
+++ b/include/linux/spinlock_up.h
@@ -0,0 +1,74 @@
+#ifndef __LINUX_SPINLOCK_UP_H
+#define __LINUX_SPINLOCK_UP_H
+
+#ifndef __LINUX_SPINLOCK_H
+# error "please don't include this file directly"
+#endif
+
+/*
+ * include/linux/spinlock_up.h - UP-debug version of spinlocks.
+ *
+ * portions Copyright 2005, Red Hat, Inc., Ingo Molnar
+ * Released under the General Public License (GPL).
+ *
+ * In the debug case, 1 means unlocked, 0 means locked. (the values
+ * are inverted, to catch initialization bugs)
+ *
+ * No atomicity anywhere, we are on UP.
+ */
+
+#ifdef CONFIG_DEBUG_SPINLOCK
+
+#define __raw_spin_is_locked(x) ((x)->slock == 0)
+
+static inline void __raw_spin_lock(raw_spinlock_t *lock)
+{
+ lock->slock = 0;
+}
+
+static inline void
+__raw_spin_lock_flags(raw_spinlock_t *lock, unsigned long flags)
+{
+ local_irq_save(flags);
+ lock->slock = 0;
+}
+
+static inline int __raw_spin_trylock(raw_spinlock_t *lock)
+{
+ char oldval = lock->slock;
+
+ lock->slock = 0;
+
+ return oldval > 0;
+}
+
+static inline void __raw_spin_unlock(raw_spinlock_t *lock)
+{
+ lock->slock = 1;
+}
+
+/*
+ * Read-write spinlocks. No debug version.
+ */
+#define __raw_read_lock(lock) do { (void)(lock); } while (0)
+#define __raw_write_lock(lock) do { (void)(lock); } while (0)
+#define __raw_read_trylock(lock) ({ (void)(lock); 1; })
+#define __raw_write_trylock(lock) ({ (void)(lock); 1; })
+#define __raw_read_unlock(lock) do { (void)(lock); } while (0)
+#define __raw_write_unlock(lock) do { (void)(lock); } while (0)
+
+#else /* DEBUG_SPINLOCK */
+#define __raw_spin_is_locked(lock) ((void)(lock), 0)
+/* for sched.c and kernel_lock.c: */
+# define __raw_spin_lock(lock) do { (void)(lock); } while (0)
+# define __raw_spin_unlock(lock) do { (void)(lock); } while (0)
+# define __raw_spin_trylock(lock) ({ (void)(lock); 1; })
+#endif /* DEBUG_SPINLOCK */
+
+#define __raw_read_can_lock(lock) (((void)(lock), 1))
+#define __raw_write_can_lock(lock) (((void)(lock), 1))
+
+#define __raw_spin_unlock_wait(lock) \
+ do { cpu_relax(); } while (__raw_spin_is_locked(lock))
+
+#endif /* __LINUX_SPINLOCK_UP_H */