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x86/spinlock changes for v3.2

GIT PULL Ingo Molnar 1 participant 1 message Oct 26, 2011

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x86 Locking primitives Atomic infrastructure x86 platform uv hpe superdome flex
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Ingo Molnar

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Linus,

Please pull the latest x86-spinlocks-for-linus git tree from:

git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git x86-spinlocks-for-linus

Thanks,

Ingo

------------------>
Jeremy Fitzhardinge (12):
x86, cmpxchg: <linux/alternative.h> has LOCK_PREFIX
x86, cmpxchg: Move 32-bit __cmpxchg_wrong_size to match 64 bit. x86, cmpxchg: Move 64-bit set64_bit() to match 32-bit
x86, cmpxchg: Unify cmpxchg into cmpxchg.h
x86: Add xadd helper macro
x86: Use xadd helper more widely
x86, ticketlock: Clean up types and accessors
x86, ticketlock: Convert spin loop to C
x86, ticketlock: Convert __ticket_spin_lock to use xadd() x86, ticketlock: Make __ticket_spin_trylock common
x86, cmpxchg: Use __compiletime_error() to make usage messages a bit nicer x86, ticketlock: remove obsolete comment

 arch/x86/include/asm/atomic.h         |    8 +-
 arch/x86/include/asm/atomic64_64.h    |    6 +-
 arch/x86/include/asm/cmpxchg.h        |  205 +++++++++++++++++++++++++++++++++
 arch/x86/include/asm/cmpxchg_32.h     |  114 ------------------
 arch/x86/include/asm/cmpxchg_64.h     |  131 ---------------------
 arch/x86/include/asm/rwsem.h          |    8 +-
 arch/x86/include/asm/spinlock.h       |  114 +++++--------------
 arch/x86/include/asm/spinlock_types.h |   22 +++-
 arch/x86/include/asm/uv/uv_bau.h      |    6 +-
 9 files changed, 257 insertions(+), 357 deletions(-)
arch/x86/include/asm/atomic.h +2 -6
index 10572e3..58cb6d4 100644
@@ -172,18 +172,14 @@ static inline int atomic_add_negative(int i, atomic_t *v)
  */
 static inline int atomic_add_return(int i, atomic_t *v)
 {
-	int __i;
 #ifdef CONFIG_M386
+	int __i;
 	unsigned long flags;
 	if (unlikely(boot_cpu_data.x86 <= 3))
 		goto no_xadd;
 #endif
 	/* Modern 486+ processor */
-	__i = i;
-	asm volatile(LOCK_PREFIX "xaddl %0, %1"
-		     : "+r" (i), "+m" (v->counter)
-		     : : "memory");
-	return i + __i;
+	return i + xadd(&v->counter, i);
 
 #ifdef CONFIG_M386
 no_xadd: /* Legacy 386 processor */
arch/x86/include/asm/atomic64_64.h +1 -5
index 017594d..0e1cbfc 100644
@@ -170,11 +170,7 @@ static inline int atomic64_add_negative(long i, atomic64_t *v)
  */
 static inline long atomic64_add_return(long i, atomic64_t *v)
 {
-	long __i = i;
-	asm volatile(LOCK_PREFIX "xaddq %0, %1;"
-		     : "+r" (i), "+m" (v->counter)
-		     : : "memory");
-	return i + __i;
+	return i + xadd(&v->counter, i);
 }
 
 static inline long atomic64_sub_return(long i, atomic64_t *v)
arch/x86/include/asm/cmpxchg.h +205 -0

210 lines not on this page · raw message

arch/x86/include/asm/cmpxchg_32.h +0 -114

133 lines not on this page · raw message

arch/x86/include/asm/cmpxchg_64.h +0 -131

144 lines not on this page · raw message

arch/x86/include/asm/rwsem.h +1 -7
index df4cd32..2dbe4a7 100644
@@ -204,13 +204,7 @@ static inline void rwsem_atomic_add(long delta, struct rw_semaphore *sem)
  */
 static inline long rwsem_atomic_update(long delta, struct rw_semaphore *sem)
 {
-	long tmp = delta;
-
-	asm volatile(LOCK_PREFIX "xadd %0,%1"
-		     : "+r" (tmp), "+m" (sem->count)
-		     : : "memory");
-
-	return tmp + delta;
+	return delta + xadd(&sem->count, delta);
 }
 
 #endif /* __KERNEL__ */
arch/x86/include/asm/spinlock.h +27 -87

152 lines not on this page · raw message

arch/x86/include/asm/spinlock_types.h +20 -2
index 7c7a486..8ebd5df 100644
@@ -5,11 +5,29 @@
 # error "please don't include this file directly"
 #endif
 
+#include <linux/types.h>
+
+#if (CONFIG_NR_CPUS < 256)
+typedef u8  __ticket_t;
+typedef u16 __ticketpair_t;
+#else
+typedef u16 __ticket_t;
+typedef u32 __ticketpair_t;
+#endif
+
+#define TICKET_SHIFT	(sizeof(__ticket_t) * 8)
+#define TICKET_MASK	((__ticket_t)((1 << TICKET_SHIFT) - 1))
+
 typedef struct arch_spinlock {
-	unsigned int slock;
+	union {
+		__ticketpair_t head_tail;
+		struct __raw_tickets {
+			__ticket_t head, tail;
+		} tickets;
+	};
 } arch_spinlock_t;
 
-#define __ARCH_SPIN_LOCK_UNLOCKED	{ 0 }
+#define __ARCH_SPIN_LOCK_UNLOCKED	{ { 0 } }
 
 #include <asm/rwlock.h>
arch/x86/include/asm/uv/uv_bau.h +1 -5
index 37d3698..c568ccc 100644
@@ -656,11 +656,7 @@ static inline int atomic_read_short(const struct atomic_short *v)
  */
 static inline int atom_asr(short i, struct atomic_short *v)
 {
-	short __i = i;
-	asm volatile(LOCK_PREFIX "xaddw %0, %1"
-			: "+r" (i), "+m" (v->counter)
-			: : "memory");
-	return i + __i;
+	return i + xadd(&v->counter, i);
 }
 
 /*