diff options
| -rw-r--r-- | arch/Kconfig | 3 | ||||
| -rw-r--r-- | arch/s390/Kconfig | 2 | ||||
| -rw-r--r-- | arch/s390/include/asm/mutex.h | 2 | ||||
| -rw-r--r-- | arch/s390/include/asm/processor.h | 2 | ||||
| -rw-r--r-- | arch/s390/include/asm/spinlock.h | 5 | ||||
| -rw-r--r-- | include/linux/mutex.h | 6 | ||||
| -rw-r--r-- | lib/lockref.c | 10 |
7 files changed, 20 insertions, 10 deletions
diff --git a/arch/Kconfig b/arch/Kconfig index 1feb169274f..af2cc6eabcc 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -286,9 +286,6 @@ config HAVE_PERF_USER_STACK_DUMP config HAVE_ARCH_JUMP_LABEL bool -config HAVE_ARCH_MUTEX_CPU_RELAX - bool - config HAVE_RCU_TABLE_FREE bool diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig index dcc6ac2d802..7143793859f 100644 --- a/arch/s390/Kconfig +++ b/arch/s390/Kconfig @@ -93,6 +93,7 @@ config S390 select ARCH_INLINE_WRITE_UNLOCK_IRQ select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE select ARCH_SAVE_PAGE_KEYS if HIBERNATION + select ARCH_USE_CMPXCHG_LOCKREF select ARCH_WANT_IPC_PARSE_VERSION select BUILDTIME_EXTABLE_SORT select CLONE_BACKWARDS2 @@ -102,7 +103,6 @@ config S390 select GENERIC_TIME_VSYSCALL_OLD select HAVE_ALIGNED_STRUCT_PAGE if SLUB select HAVE_ARCH_JUMP_LABEL if !MARCH_G5 - select HAVE_ARCH_MUTEX_CPU_RELAX select HAVE_ARCH_SECCOMP_FILTER select HAVE_ARCH_TRACEHOOK select HAVE_ARCH_TRANSPARENT_HUGEPAGE if 64BIT diff --git a/arch/s390/include/asm/mutex.h b/arch/s390/include/asm/mutex.h index 688271f5f2e..458c1f7fbc1 100644 --- a/arch/s390/include/asm/mutex.h +++ b/arch/s390/include/asm/mutex.h @@ -7,5 +7,3 @@ */ #include <asm-generic/mutex-dec.h> - -#define arch_mutex_cpu_relax() barrier() diff --git a/arch/s390/include/asm/processor.h b/arch/s390/include/asm/processor.h index 0eb37505cab..ca7821f0726 100644 --- a/arch/s390/include/asm/processor.h +++ b/arch/s390/include/asm/processor.h @@ -198,6 +198,8 @@ static inline void cpu_relax(void) barrier(); } +#define arch_mutex_cpu_relax() barrier() + static inline void psw_set_key(unsigned int key) { asm volatile("spka 0(%0)" : : "d" (key)); diff --git a/arch/s390/include/asm/spinlock.h b/arch/s390/include/asm/spinlock.h index 701fe8c59e1..83e5d216105 100644 --- a/arch/s390/include/asm/spinlock.h +++ b/arch/s390/include/asm/spinlock.h @@ -44,6 +44,11 @@ extern void arch_spin_lock_wait_flags(arch_spinlock_t *, unsigned long flags); extern int arch_spin_trylock_retry(arch_spinlock_t *); extern void arch_spin_relax(arch_spinlock_t *lock); +static inline int arch_spin_value_unlocked(arch_spinlock_t lock) +{ + return lock.owner_cpu == 0; +} + static inline void arch_spin_lock(arch_spinlock_t *lp) { int old; diff --git a/include/linux/mutex.h b/include/linux/mutex.h index ccd4260834c..bab49da8a0f 100644 --- a/include/linux/mutex.h +++ b/include/linux/mutex.h @@ -15,8 +15,8 @@ #include <linux/spinlock_types.h> #include <linux/linkage.h> #include <linux/lockdep.h> - #include <linux/atomic.h> +#include <asm/processor.h> /* * Simple, straightforward mutexes with strict semantics: @@ -175,8 +175,8 @@ extern void mutex_unlock(struct mutex *lock); extern int atomic_dec_and_mutex_lock(atomic_t *cnt, struct mutex *lock); -#ifndef CONFIG_HAVE_ARCH_MUTEX_CPU_RELAX -#define arch_mutex_cpu_relax() cpu_relax() +#ifndef arch_mutex_cpu_relax +# define arch_mutex_cpu_relax() cpu_relax() #endif #endif diff --git a/lib/lockref.c b/lib/lockref.c index e294ae445c9..6f9d434c152 100644 --- a/lib/lockref.c +++ b/lib/lockref.c @@ -12,6 +12,14 @@ #endif /* + * Allow architectures to override the default cpu_relax() within CMPXCHG_LOOP. + * This is useful for architectures with an expensive cpu_relax(). + */ +#ifndef arch_mutex_cpu_relax +# define arch_mutex_cpu_relax() cpu_relax() +#endif + +/* * Note that the "cmpxchg()" reloads the "old" value for the * failure case. */ @@ -28,7 +36,7 @@ if (likely(old.lock_count == prev.lock_count)) { \ SUCCESS; \ } \ - cpu_relax(); \ + arch_mutex_cpu_relax(); \ } \ } while (0) |