[patch 4/4] x86: spinlock.h merge

[Nick Piggin]

Merge spinlock_32.h and spinlock_64.h into spinlock.h.

Signed-off-by: Nick Piggin <npiggin@xxxxxxx>
---
Index: linux-2.6/include/asm-x86/spinlock.h
===================================================================
--- linux-2.6.orig/include/asm-x86/spinlock.h
+++ linux-2.6/include/asm-x86/spinlock.h
@@ -1,5 +1,211 @@
-#ifdef CONFIG_X86_32
-# include "spinlock_32.h"
+#ifndef __ASM_SPINLOCK_H
+#define __ASM_SPINLOCK_H
+
+#include <asm/atomic.h>
+#include <asm/rwlock.h>
+#include <asm/page.h>
+#include <asm/processor.h>
+#include <linux/compiler.h>
+
+/*
+ * Your basic SMP spinlocks, allowing only a single CPU anywhere
+ *
+ * Simple spin lock operations.  There are two variants, one clears IRQ's
+ * on the local processor, one does not.
+ *
+ * These are fair FIFO ticket locks, which are currently limited to 256
+ * CPUs.
+ *
+ * (the type definitions are in asm/spinlock_types.h)
+ */
+
+#if (NR_CPUS > 256)
+#error spinlock supports a maximum of 256 CPUs
+#endif
+
+static inline int __raw_spin_is_locked(raw_spinlock_t *lock)
+{
+	int tmp = *(volatile signed int *)(&(lock)->slock);
+
+	return (((tmp >> 8) & 0xff) != (tmp & 0xff));
+}
+
+static inline int __raw_spin_is_contended(raw_spinlock_t *lock)
+{
+	int tmp = *(volatile signed int *)(&(lock)->slock);
+
+	return (((tmp >> 8) & 0xff) - (tmp & 0xff)) > 1;
+}
+
+static inline void __raw_spin_lock(raw_spinlock_t *lock)
+{
+	short inc = 0x0100;
+
+	/*
+	 * Ticket locks are conceptually two bytes, one indicating the current
+	 * head of the queue, and the other indicating the current tail. The
+	 * lock is acquired by atomically noting the tail and incrementing it
+	 * by one (thus adding ourself to the queue and noting our position),
+	 * then waiting until the head becomes equal to the the initial value
+	 * of the tail.
+	 *
+	 * This uses a 16-bit xadd to increment the tail and also load the
+	 * position of the head, which takes care of memory ordering issues
+	 * and should be optimal for the uncontended case. Note the tail must
+	 * be in the high byte, otherwise the 16-bit wide increment of the low
+	 * byte would carry up and contaminate the high byte.
+	 */
+
+	__asm__ __volatile__ (
+		LOCK_PREFIX "xaddw %w0, %1\n"
+		"1:\t"
+		"cmpb %h0, %b0\n\t"
+		"je 2f\n\t"
+		"rep ; nop\n\t"
+		"movb %1, %b0\n\t"
+		/* don't need lfence here, because loads are in-order */
+		"jmp 1b\n"
+		"2:"
+		:"+Q" (inc), "+m" (lock->slock)
+		:
+		:"memory", "cc");
+}
+
+#define __raw_spin_lock_flags(lock, flags) __raw_spin_lock(lock)
+
+static inline int __raw_spin_trylock(raw_spinlock_t *lock)
+{
+	short prev;
+	short new;
+	int ret = 0;
+
+	asm volatile(
+		"movw %2,%w0\n\t"
+		"cmpb %h0,%b0\n\t"
+		"jne 1f\n\t"
+		"movw %w0,%w1\n\t"
+		"incb %h1\n\t"
+		"lock ; cmpxchgw %w1,%2\n\t"
+		"decb %h1\n\t"
+		"cmpw %w0,%w1\n\t"
+		"jne 1f\n\t"
+		"movl $1,%3\n\t"
+		"1:"
+		:"=a" (prev), "=Q" (new), "+m" (lock->slock), "+m" (ret)
+		:
+		: "memory", "cc");
+
+	return ret;
+}
+
+#if defined(CONFIG_X86_32) && \
+	(defined(CONFIG_X86_OOSTORE) || defined(CONFIG_X86_PPRO_FENCE))
+/*
+ * On PPro SMP or if we are using OOSTORE, we use a locked operation to unlock
+ * (PPro errata 66, 92)
+ */
+# define UNLOCK_LOCK_PREFIX LOCK_PREFIX
 #else
-# include "spinlock_64.h"
+# define UNLOCK_LOCK_PREFIX
 #endif
+
+static inline void __raw_spin_unlock(raw_spinlock_t *lock)
+{
+	__asm__ __volatile__(
+		UNLOCK_LOCK_PREFIX "incb %0"
+		:"+m" (lock->slock)
+		:
+		:"memory", "cc");
+}
+
+static inline void __raw_spin_unlock_wait(raw_spinlock_t *lock)
+{
+	while (__raw_spin_is_locked(lock))
+		cpu_relax();
+}
+
+/*
+ * Read-write spinlocks, allowing multiple readers
+ * but only one writer.
+ *
+ * NOTE! it is quite common to have readers in interrupts
+ * but no interrupt writers. For those circumstances we
+ * can "mix" irq-safe locks - any writer needs to get a
+ * irq-safe write-lock, but readers can get non-irqsafe
+ * read-locks.
+ *
+ * On x86, we implement read-write locks as a 32-bit counter
+ * with the high bit (sign) being the "contended" bit.
+ */
+
+/**
+ * read_can_lock - would read_trylock() succeed?
+ * @lock: the rwlock in question.
+ */
+static inline int __raw_read_can_lock(raw_rwlock_t *lock)
+{
+	return (int)(lock)->lock > 0;
+}
+
+/**
+ * write_can_lock - would write_trylock() succeed?
+ * @lock: the rwlock in question.
+ */
+static inline int __raw_write_can_lock(raw_rwlock_t *lock)
+{
+	return (lock)->lock == RW_LOCK_BIAS;
+}
+
+static inline void __raw_read_lock(raw_rwlock_t *rw)
+{
+	asm volatile(LOCK_PREFIX "subl $1,(%0)\n\t"
+		     "jns 1f\n"
+		     "call __read_lock_failed\n\t"
+		     "1:\n"
+		     ::"r" (rw) : "memory");
+}
+
+static inline void __raw_write_lock(raw_rwlock_t *rw)
+{
+	asm volatile(LOCK_PREFIX "subl %1,(%0)\n\t"
+		     "jz 1f\n"
+		     "call __write_lock_failed\n\t"
+		     "1:\n"
+		     ::"r" (rw), "i" (RW_LOCK_BIAS) : "memory");
+}
+
+static inline int __raw_read_trylock(raw_rwlock_t *lock)
+{
+	atomic_t *count = (atomic_t *)lock;
+	atomic_dec(count);
+	if (atomic_read(count) >= 0)
+		return 1;
+	atomic_inc(count);
+	return 0;
+}
+
+static inline int __raw_write_trylock(raw_rwlock_t *lock)
+{
+	atomic_t *count = (atomic_t *)lock;
+	if (atomic_sub_and_test(RW_LOCK_BIAS, count))
+		return 1;
+	atomic_add(RW_LOCK_BIAS, count);
+	return 0;
+}
+
+static inline void __raw_read_unlock(raw_rwlock_t *rw)
+{
+	asm volatile(LOCK_PREFIX "incl %0" :"+m" (rw->lock) : : "memory");
+}
+
+static inline void __raw_write_unlock(raw_rwlock_t *rw)
+{
+	asm volatile(LOCK_PREFIX "addl %1,%0"
+			: "+m" (rw->lock) : "i" (RW_LOCK_BIAS) : "memory");
+}
+
+#define _raw_spin_relax(lock)	cpu_relax()
+#define _raw_read_relax(lock)	cpu_relax()
+#define _raw_write_relax(lock)	cpu_relax()
+
+#endif /* __ASM_SPINLOCK_H */
Index: linux-2.6/include/asm-x86/spinlock_32.h
===================================================================
--- linux-2.6.orig/include/asm-x86/spinlock_32.h
+++ /dev/null
@@ -1,211 +0,0 @@
-#ifndef __ASM_SPINLOCK_H
-#define __ASM_SPINLOCK_H
-
-#include <asm/atomic.h>
-#include <asm/rwlock.h>
-#include <asm/page.h>
-#include <asm/processor.h>
-#include <linux/compiler.h>
-
-/*
- * Your basic SMP spinlocks, allowing only a single CPU anywhere
- *
- * Simple spin lock operations.  There are two variants, one clears IRQ's
- * on the local processor, one does not.
- *
- * These are fair FIFO ticket locks, which are currently limited to 256
- * CPUs.
- *
- * (the type definitions are in asm/spinlock_types.h)
- */
-
-#if (NR_CPUS > 256)
-#error spinlock supports a maximum of 256 CPUs
-#endif
-
-static inline int __raw_spin_is_locked(raw_spinlock_t *lock)
-{
-	int tmp = *(volatile signed int *)(&(lock)->slock);
-
-	return (((tmp >> 8) & 0xff) != (tmp & 0xff));
-}
-
-static inline int __raw_spin_is_contended(raw_spinlock_t *lock)
-{
-	int tmp = *(volatile signed int *)(&(lock)->slock);
-
-	return (((tmp >> 8) & 0xff) - (tmp & 0xff)) > 1;
-}
-
-static inline void __raw_spin_lock(raw_spinlock_t *lock)
-{
-	short inc = 0x0100;
-
-	/*
-	 * Ticket locks are conceptually two bytes, one indicating the current
-	 * head of the queue, and the other indicating the current tail. The
-	 * lock is acquired by atomically noting the tail and incrementing it
-	 * by one (thus adding ourself to the queue and noting our position),
-	 * then waiting until the head becomes equal to the the initial value
-	 * of the tail.
-	 *
-	 * This uses a 16-bit xadd to increment the tail and also load the
-	 * position of the head, which takes care of memory ordering issues
-	 * and should be optimal for the uncontended case. Note the tail must
-	 * be in the high byte, otherwise the 16-bit wide increment of the low
-	 * byte would carry up and contaminate the high byte.
-	 */
-
-	__asm__ __volatile__ (
-		LOCK_PREFIX "xaddw %w0, %1\n"
-		"1:\t"
-		"cmpb %h0, %b0\n\t"
-		"je 2f\n\t"
-		"rep ; nop\n\t"
-		"movb %1, %b0\n\t"
-		/* don't need lfence here, because loads are in-order */
-		"jmp 1b\n"
-		"2:"
-		:"+Q" (inc), "+m" (lock->slock)
-		:
-		:"memory", "cc");
-}
-
-#define __raw_spin_lock_flags(lock, flags) __raw_spin_lock(lock)
-
-static inline int __raw_spin_trylock(raw_spinlock_t *lock)
-{
-	short prev;
-	short new;
-	int ret = 0;
-
-	asm volatile(
-		"movw %2,%w0\n\t"
-		"cmpb %h0,%b0\n\t"
-		"jne 1f\n\t"
-		"movw %w0,%w1\n\t"
-		"incb %h1\n\t"
-		"lock ; cmpxchgw %w1,%2\n\t"
-		"decb %h1\n\t"
-		"cmpw %w0,%w1\n\t"
-		"jne 1f\n\t"
-		"movl $1,%3\n\t"
-		"1:"
-		:"=a" (prev), "=Q" (new), "+m" (lock->slock), "+m" (ret)
-		:
-		: "memory", "cc");
-
-	return ret;
-}
-
-#if defined(CONFIG_X86_32) && \
-	(defined(CONFIG_X86_OOSTORE) || defined(CONFIG_X86_PPRO_FENCE))
-/*
- * On PPro SMP or if we are using OOSTORE, we use a locked operation to unlock
- * (PPro errata 66, 92)
- */
-# define UNLOCK_LOCK_PREFIX LOCK_PREFIX
-#else
-# define UNLOCK_LOCK_PREFIX
-#endif
-
-static inline void __raw_spin_unlock(raw_spinlock_t *lock)
-{
-	__asm__ __volatile__(
-		UNLOCK_LOCK_PREFIX "incb %0"
-		:"+m" (lock->slock)
-		:
-		:"memory", "cc");
-}
-
-static inline void __raw_spin_unlock_wait(raw_spinlock_t *lock)
-{
-	while (__raw_spin_is_locked(lock))
-		cpu_relax();
-}
-
-/*
- * Read-write spinlocks, allowing multiple readers
- * but only one writer.
- *
- * NOTE! it is quite common to have readers in interrupts
- * but no interrupt writers. For those circumstances we
- * can "mix" irq-safe locks - any writer needs to get a
- * irq-safe write-lock, but readers can get non-irqsafe
- * read-locks.
- *
- * On x86, we implement read-write locks as a 32-bit counter
- * with the high bit (sign) being the "contended" bit.
- */
-
-/**
- * read_can_lock - would read_trylock() succeed?
- * @lock: the rwlock in question.
- */
-static inline int __raw_read_can_lock(raw_rwlock_t *lock)
-{
-	return (int)(lock)->lock > 0;
-}
-
-/**
- * write_can_lock - would write_trylock() succeed?
- * @lock: the rwlock in question.
- */
-static inline int __raw_write_can_lock(raw_rwlock_t *lock)
-{
-	return (lock)->lock == RW_LOCK_BIAS;
-}
-
-static inline void __raw_read_lock(raw_rwlock_t *rw)
-{
-	asm volatile(LOCK_PREFIX "subl $1,(%0)\n\t"
-		     "jns 1f\n"
-		     "call __read_lock_failed\n\t"
-		     "1:\n"
-		     ::"r" (rw) : "memory");
-}
-
-static inline void __raw_write_lock(raw_rwlock_t *rw)
-{
-	asm volatile(LOCK_PREFIX "subl %1,(%0)\n\t"
-		     "jz 1f\n"
-		     "call __write_lock_failed\n\t"
-		     "1:\n"
-		     ::"r" (rw), "i" (RW_LOCK_BIAS) : "memory");
-}
-
-static inline int __raw_read_trylock(raw_rwlock_t *lock)
-{
-	atomic_t *count = (atomic_t *)lock;
-	atomic_dec(count);
-	if (atomic_read(count) >= 0)
-		return 1;
-	atomic_inc(count);
-	return 0;
-}
-
-static inline int __raw_write_trylock(raw_rwlock_t *lock)
-{
-	atomic_t *count = (atomic_t *)lock;
-	if (atomic_sub_and_test(RW_LOCK_BIAS, count))
-		return 1;
-	atomic_add(RW_LOCK_BIAS, count);
-	return 0;
-}
-
-static inline void __raw_read_unlock(raw_rwlock_t *rw)
-{
-	asm volatile(LOCK_PREFIX "incl %0" :"+m" (rw->lock) : : "memory");
-}
-
-static inline void __raw_write_unlock(raw_rwlock_t *rw)
-{
-	asm volatile(LOCK_PREFIX "addl %1,%0"
-			: "+m" (rw->lock) : "i" (RW_LOCK_BIAS) : "memory");
-}
-
-#define _raw_spin_relax(lock)	cpu_relax()
-#define _raw_read_relax(lock)	cpu_relax()
-#define _raw_write_relax(lock)	cpu_relax()
-
-#endif /* __ASM_SPINLOCK_H */
Index: linux-2.6/include/asm-x86/spinlock_64.h
===================================================================
--- linux-2.6.orig/include/asm-x86/spinlock_64.h
+++ /dev/null
@@ -1,200 +0,0 @@
-#ifndef __ASM_SPINLOCK_H
-#define __ASM_SPINLOCK_H
-
-#include <asm/atomic.h>
-#include <asm/rwlock.h>
-#include <asm/page.h>
-#include <asm/processor.h>
-#include <linux/compiler.h>
-
-/*
- * Your basic SMP spinlocks, allowing only a single CPU anywhere
- *
- * Simple spin lock operations.  There are two variants, one clears IRQ's
- * on the local processor, one does not.
- *
- * These are fair FIFO ticket locks, which are currently limited to 256
- * CPUs.
- *
- * (the type definitions are in asm/spinlock_types.h)
- */
-
-#if (NR_CPUS > 256)
-#error spinlock supports a maximum of 256 CPUs
-#endif
-
-static inline int __raw_spin_is_locked(raw_spinlock_t *lock)
-{
-	int tmp = *(volatile signed int *)(&(lock)->slock);
-
-	return (((tmp >> 8) & 0xff) != (tmp & 0xff));
-}
-
-static inline int __raw_spin_is_contended(raw_spinlock_t *lock)
-{
-	int tmp = *(volatile signed int *)(&(lock)->slock);
-
-	return (((tmp >> 8) & 0xff) - (tmp & 0xff)) > 1;
-}
-
-static inline void __raw_spin_lock(raw_spinlock_t *lock)
-{
-	short inc = 0x0100;
-
-	/*
-	 * Ticket locks are conceptually two bytes, one indicating the current
-	 * head of the queue, and the other indicating the current tail. The
-	 * lock is acquired by atomically noting the tail and incrementing it
-	 * by one (thus adding ourself to the queue and noting our position),
-	 * then waiting until the head becomes equal to the the initial value
-	 * of the tail.
-	 *
-	 * This uses a 16-bit xadd to increment the tail and also load the
-	 * position of the head, which takes care of memory ordering issues
-	 * and should be optimal for the uncontended case. Note the tail must
-	 * be in the high byte, otherwise the 16-bit wide increment of the low
-	 * byte would carry up and contaminate the high byte.
-	 */
-
-	__asm__ __volatile__ (
-		LOCK_PREFIX "xaddw %w0, %1\n"
-		"1:\t"
-		"cmpb %h0, %b0\n\t"
-		"je 2f\n\t"
-		"rep ; nop\n\t"
-		"movb %1, %b0\n\t"
-		/* don't need lfence here, because loads are in-order */
-		"jmp 1b\n"
-		"2:"
-		:"+Q" (inc), "+m" (lock->slock)
-		:
-		:"memory", "cc");
-}
-
-#define __raw_spin_lock_flags(lock, flags) __raw_spin_lock(lock)
-
-static inline int __raw_spin_trylock(raw_spinlock_t *lock)
-{
-	short prev;
-	short new;
-	int ret = 0;
-
-	asm volatile(
-		"movw %2,%w0\n\t"
-		"cmpb %h0,%b0\n\t"
-		"jne 1f\n\t"
-		"movw %w0,%w1\n\t"
-		"incb %h1\n\t"
-		"lock ; cmpxchgw %w1,%2\n\t"
-		"decb %h1\n\t"
-		"cmpw %w0,%w1\n\t"
-		"jne 1f\n\t"
-		"movl $1,%3\n\t"
-		"1:"
-		:"=a" (prev), "=Q" (new), "+m" (lock->slock), "+m" (ret)
-		:
-		: "memory", "cc");
-
-	return ret;
-}
-
-static inline void __raw_spin_unlock(raw_spinlock_t *lock)
-{
-	__asm__ __volatile__(
-		"incb %0"
-		:"+m" (lock->slock)
-		:
-		:"memory", "cc");
-}
-
-static inline void __raw_spin_unlock_wait(raw_spinlock_t *lock)
-{
-	while (__raw_spin_is_locked(lock))
-		cpu_relax();
-}
-
-/*
- * Read-write spinlocks, allowing multiple readers
- * but only one writer.
- *
- * NOTE! it is quite common to have readers in interrupts
- * but no interrupt writers. For those circumstances we
- * can "mix" irq-safe locks - any writer needs to get a
- * irq-safe write-lock, but readers can get non-irqsafe
- * read-locks.
- *
- * On x86, we implement read-write locks as a 32-bit counter
- * with the high bit (sign) being the "contended" bit.
- */
-
-/**
- * read_can_lock - would read_trylock() succeed?
- * @lock: the rwlock in question.
- */
-static inline int __raw_read_can_lock(raw_rwlock_t *lock)
-{
-	return (int)(lock)->lock > 0;
-}
-
-/**
- * write_can_lock - would write_trylock() succeed?
- * @lock: the rwlock in question.
- */
-static inline int __raw_write_can_lock(raw_rwlock_t *lock)
-{
-	return (lock)->lock == RW_LOCK_BIAS;
-}
-
-static inline void __raw_read_lock(raw_rwlock_t *rw)
-{
-	asm volatile(LOCK_PREFIX "subl $1,(%0)\n\t"
-		     "jns 1f\n"
-		     "call __read_lock_failed\n\t"
-		     "1:\n"
-		     ::"r" (rw) : "memory");
-}
-
-static inline void __raw_write_lock(raw_rwlock_t *rw)
-{
-	asm volatile(LOCK_PREFIX "subl %1,(%0)\n\t"
-		     "jz 1f\n"
-		     "call __write_lock_failed\n\t"
-		     "1:\n"
-		     ::"r" (rw), "i" (RW_LOCK_BIAS) : "memory");
-}
-
-static inline int __raw_read_trylock(raw_rwlock_t *lock)
-{
-	atomic_t *count = (atomic_t *)lock;
-	atomic_dec(count);
-	if (atomic_read(count) >= 0)
-		return 1;
-	atomic_inc(count);
-	return 0;
-}
-
-static inline int __raw_write_trylock(raw_rwlock_t *lock)
-{
-	atomic_t *count = (atomic_t *)lock;
-	if (atomic_sub_and_test(RW_LOCK_BIAS, count))
-		return 1;
-	atomic_add(RW_LOCK_BIAS, count);
-	return 0;
-}
-
-static inline void __raw_read_unlock(raw_rwlock_t *rw)
-{
-	asm volatile(LOCK_PREFIX "incl %0" :"+m" (rw->lock) : : "memory");
-}
-
-static inline void __raw_write_unlock(raw_rwlock_t *rw)
-{
-	asm volatile(LOCK_PREFIX "addl %1,%0"
-			: "+m" (rw->lock) : "i" (RW_LOCK_BIAS) : "memory");
-}
-
-#define _raw_spin_relax(lock)	cpu_relax()
-#define _raw_read_relax(lock)	cpu_relax()
-#define _raw_write_relax(lock)	cpu_relax()
-
-#endif /* __ASM_SPINLOCK_H */
-
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