To prepare for queued spinlocks. This is a simple rename except to update preprocessor guard name and a file reference. Signed-off-by: Nicholas Piggin <npiggin@xxxxxxxxx> --- arch/powerpc/include/asm/simple_spinlock.h | 288 ++++++++++++++++++ .../include/asm/simple_spinlock_types.h | 21 ++ arch/powerpc/include/asm/spinlock.h | 285 +---------------- arch/powerpc/include/asm/spinlock_types.h | 12 +- 4 files changed, 311 insertions(+), 295 deletions(-) create mode 100644 arch/powerpc/include/asm/simple_spinlock.h create mode 100644 arch/powerpc/include/asm/simple_spinlock_types.h diff --git a/arch/powerpc/include/asm/simple_spinlock.h b/arch/powerpc/include/asm/simple_spinlock.h new file mode 100644 index 000000000000..fe6cff7df48e --- /dev/null +++ b/arch/powerpc/include/asm/simple_spinlock.h @@ -0,0 +1,288 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +#ifndef _ASM_POWERPC_SIMPLE_SPINLOCK_H +#define _ASM_POWERPC_SIMPLE_SPINLOCK_H + +/* + * Simple spin lock operations. + * + * Copyright (C) 2001-2004 Paul Mackerras <paulus@xxxxxxxxxx>, IBM + * Copyright (C) 2001 Anton Blanchard <anton@xxxxxxxxxx>, IBM + * Copyright (C) 2002 Dave Engebretsen <engebret@xxxxxxxxxx>, IBM + * Rework to support virtual processors + * + * Type of int is used as a full 64b word is not necessary. + * + * (the type definitions are in asm/simple_spinlock_types.h) + */ +#include <linux/irqflags.h> +#include <asm/paravirt.h> +#include <asm/paca.h> +#include <asm/synch.h> +#include <asm/ppc-opcode.h> + +#ifdef CONFIG_PPC64 +/* use 0x800000yy when locked, where yy == CPU number */ +#ifdef __BIG_ENDIAN__ +#define LOCK_TOKEN (*(u32 *)(&get_paca()->lock_token)) +#else +#define LOCK_TOKEN (*(u32 *)(&get_paca()->paca_index)) +#endif +#else +#define LOCK_TOKEN 1 +#endif + +static __always_inline int arch_spin_value_unlocked(arch_spinlock_t lock) +{ + return lock.slock == 0; +} + +static inline int arch_spin_is_locked(arch_spinlock_t *lock) +{ + smp_mb(); + return !arch_spin_value_unlocked(*lock); +} + +/* + * This returns the old value in the lock, so we succeeded + * in getting the lock if the return value is 0. + */ +static inline unsigned long __arch_spin_trylock(arch_spinlock_t *lock) +{ + unsigned long tmp, token; + + token = LOCK_TOKEN; + __asm__ __volatile__( +"1: " PPC_LWARX(%0,0,%2,1) "\n\ + cmpwi 0,%0,0\n\ + bne- 2f\n\ + stwcx. %1,0,%2\n\ + bne- 1b\n" + PPC_ACQUIRE_BARRIER +"2:" + : "=&r" (tmp) + : "r" (token), "r" (&lock->slock) + : "cr0", "memory"); + + return tmp; +} + +static inline int arch_spin_trylock(arch_spinlock_t *lock) +{ + return __arch_spin_trylock(lock) == 0; +} + +/* + * On a system with shared processors (that is, where a physical + * processor is multiplexed between several virtual processors), + * there is no point spinning on a lock if the holder of the lock + * isn't currently scheduled on a physical processor. Instead + * we detect this situation and ask the hypervisor to give the + * rest of our timeslice to the lock holder. + * + * So that we can tell which virtual processor is holding a lock, + * we put 0x80000000 | smp_processor_id() in the lock when it is + * held. Conveniently, we have a word in the paca that holds this + * value. + */ + +#if defined(CONFIG_PPC_SPLPAR) +/* We only yield to the hypervisor if we are in shared processor mode */ +void splpar_spin_yield(arch_spinlock_t *lock); +void splpar_rw_yield(arch_rwlock_t *lock); +#else /* SPLPAR */ +static inline void splpar_spin_yield(arch_spinlock_t *lock) {}; +static inline void splpar_rw_yield(arch_rwlock_t *lock) {}; +#endif + +static inline void spin_yield(arch_spinlock_t *lock) +{ + if (is_shared_processor()) + splpar_spin_yield(lock); + else + barrier(); +} + +static inline void rw_yield(arch_rwlock_t *lock) +{ + if (is_shared_processor()) + splpar_rw_yield(lock); + else + barrier(); +} + +static inline void arch_spin_lock(arch_spinlock_t *lock) +{ + while (1) { + if (likely(__arch_spin_trylock(lock) == 0)) + break; + do { + HMT_low(); + if (is_shared_processor()) + splpar_spin_yield(lock); + } while (unlikely(lock->slock != 0)); + HMT_medium(); + } +} + +static inline +void arch_spin_lock_flags(arch_spinlock_t *lock, unsigned long flags) +{ + unsigned long flags_dis; + + while (1) { + if (likely(__arch_spin_trylock(lock) == 0)) + break; + local_save_flags(flags_dis); + local_irq_restore(flags); + do { + HMT_low(); + if (is_shared_processor()) + splpar_spin_yield(lock); + } while (unlikely(lock->slock != 0)); + HMT_medium(); + local_irq_restore(flags_dis); + } +} +#define arch_spin_lock_flags arch_spin_lock_flags + +static inline void arch_spin_unlock(arch_spinlock_t *lock) +{ + __asm__ __volatile__("# arch_spin_unlock\n\t" + PPC_RELEASE_BARRIER: : :"memory"); + lock->slock = 0; +} + +/* + * 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. + */ + +#ifdef CONFIG_PPC64 +#define __DO_SIGN_EXTEND "extsw %0,%0\n" +#define WRLOCK_TOKEN LOCK_TOKEN /* it's negative */ +#else +#define __DO_SIGN_EXTEND +#define WRLOCK_TOKEN (-1) +#endif + +/* + * This returns the old value in the lock + 1, + * so we got a read lock if the return value is > 0. + */ +static inline long __arch_read_trylock(arch_rwlock_t *rw) +{ + long tmp; + + __asm__ __volatile__( +"1: " PPC_LWARX(%0,0,%1,1) "\n" + __DO_SIGN_EXTEND +" addic. %0,%0,1\n\ + ble- 2f\n" +" stwcx. %0,0,%1\n\ + bne- 1b\n" + PPC_ACQUIRE_BARRIER +"2:" : "=&r" (tmp) + : "r" (&rw->lock) + : "cr0", "xer", "memory"); + + return tmp; +} + +/* + * This returns the old value in the lock, + * so we got the write lock if the return value is 0. + */ +static inline long __arch_write_trylock(arch_rwlock_t *rw) +{ + long tmp, token; + + token = WRLOCK_TOKEN; + __asm__ __volatile__( +"1: " PPC_LWARX(%0,0,%2,1) "\n\ + cmpwi 0,%0,0\n\ + bne- 2f\n" +" stwcx. %1,0,%2\n\ + bne- 1b\n" + PPC_ACQUIRE_BARRIER +"2:" : "=&r" (tmp) + : "r" (token), "r" (&rw->lock) + : "cr0", "memory"); + + return tmp; +} + +static inline void arch_read_lock(arch_rwlock_t *rw) +{ + while (1) { + if (likely(__arch_read_trylock(rw) > 0)) + break; + do { + HMT_low(); + if (is_shared_processor()) + splpar_rw_yield(rw); + } while (unlikely(rw->lock < 0)); + HMT_medium(); + } +} + +static inline void arch_write_lock(arch_rwlock_t *rw) +{ + while (1) { + if (likely(__arch_write_trylock(rw) == 0)) + break; + do { + HMT_low(); + if (is_shared_processor()) + splpar_rw_yield(rw); + } while (unlikely(rw->lock != 0)); + HMT_medium(); + } +} + +static inline int arch_read_trylock(arch_rwlock_t *rw) +{ + return __arch_read_trylock(rw) > 0; +} + +static inline int arch_write_trylock(arch_rwlock_t *rw) +{ + return __arch_write_trylock(rw) == 0; +} + +static inline void arch_read_unlock(arch_rwlock_t *rw) +{ + long tmp; + + __asm__ __volatile__( + "# read_unlock\n\t" + PPC_RELEASE_BARRIER +"1: lwarx %0,0,%1\n\ + addic %0,%0,-1\n" +" stwcx. %0,0,%1\n\ + bne- 1b" + : "=&r"(tmp) + : "r"(&rw->lock) + : "cr0", "xer", "memory"); +} + +static inline void arch_write_unlock(arch_rwlock_t *rw) +{ + __asm__ __volatile__("# write_unlock\n\t" + PPC_RELEASE_BARRIER: : :"memory"); + rw->lock = 0; +} + +#define arch_spin_relax(lock) spin_yield(lock) +#define arch_read_relax(lock) rw_yield(lock) +#define arch_write_relax(lock) rw_yield(lock) + +/* See include/linux/spinlock.h */ +#define smp_mb__after_spinlock() smp_mb() + +#endif /* _ASM_POWERPC_SIMPLE_SPINLOCK_H */ diff --git a/arch/powerpc/include/asm/simple_spinlock_types.h b/arch/powerpc/include/asm/simple_spinlock_types.h new file mode 100644 index 000000000000..0f3cdd8faa95 --- /dev/null +++ b/arch/powerpc/include/asm/simple_spinlock_types.h @@ -0,0 +1,21 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _ASM_POWERPC_SIMPLE_SPINLOCK_TYPES_H +#define _ASM_POWERPC_SIMPLE_SPINLOCK_TYPES_H + +#ifndef __LINUX_SPINLOCK_TYPES_H +# error "please don't include this file directly" +#endif + +typedef struct { + volatile unsigned int slock; +} arch_spinlock_t; + +#define __ARCH_SPIN_LOCK_UNLOCKED { 0 } + +typedef struct { + volatile signed int lock; +} arch_rwlock_t; + +#define __ARCH_RW_LOCK_UNLOCKED { 0 } + +#endif /* _ASM_POWERPC_SIMPLE_SPINLOCK_TYPES_H */ diff --git a/arch/powerpc/include/asm/spinlock.h b/arch/powerpc/include/asm/spinlock.h index 79be9bb10bbb..21357fe05fe0 100644 --- a/arch/powerpc/include/asm/spinlock.h +++ b/arch/powerpc/include/asm/spinlock.h @@ -3,290 +3,7 @@ #define __ASM_SPINLOCK_H #ifdef __KERNEL__ -/* - * Simple spin lock operations. - * - * Copyright (C) 2001-2004 Paul Mackerras <paulus@xxxxxxxxxx>, IBM - * Copyright (C) 2001 Anton Blanchard <anton@xxxxxxxxxx>, IBM - * Copyright (C) 2002 Dave Engebretsen <engebret@xxxxxxxxxx>, IBM - * Rework to support virtual processors - * - * Type of int is used as a full 64b word is not necessary. - * - * (the type definitions are in asm/spinlock_types.h) - */ -#include <linux/irqflags.h> -#include <asm/paravirt.h> -#ifdef CONFIG_PPC64 -#include <asm/paca.h> -#endif -#include <asm/synch.h> -#include <asm/ppc-opcode.h> - -#ifdef CONFIG_PPC64 -/* use 0x800000yy when locked, where yy == CPU number */ -#ifdef __BIG_ENDIAN__ -#define LOCK_TOKEN (*(u32 *)(&get_paca()->lock_token)) -#else -#define LOCK_TOKEN (*(u32 *)(&get_paca()->paca_index)) -#endif -#else -#define LOCK_TOKEN 1 -#endif - -static __always_inline int arch_spin_value_unlocked(arch_spinlock_t lock) -{ - return lock.slock == 0; -} - -static inline int arch_spin_is_locked(arch_spinlock_t *lock) -{ - smp_mb(); - return !arch_spin_value_unlocked(*lock); -} - -/* - * This returns the old value in the lock, so we succeeded - * in getting the lock if the return value is 0. - */ -static inline unsigned long __arch_spin_trylock(arch_spinlock_t *lock) -{ - unsigned long tmp, token; - - token = LOCK_TOKEN; - __asm__ __volatile__( -"1: " PPC_LWARX(%0,0,%2,1) "\n\ - cmpwi 0,%0,0\n\ - bne- 2f\n\ - stwcx. %1,0,%2\n\ - bne- 1b\n" - PPC_ACQUIRE_BARRIER -"2:" - : "=&r" (tmp) - : "r" (token), "r" (&lock->slock) - : "cr0", "memory"); - - return tmp; -} - -static inline int arch_spin_trylock(arch_spinlock_t *lock) -{ - return __arch_spin_trylock(lock) == 0; -} - -/* - * On a system with shared processors (that is, where a physical - * processor is multiplexed between several virtual processors), - * there is no point spinning on a lock if the holder of the lock - * isn't currently scheduled on a physical processor. Instead - * we detect this situation and ask the hypervisor to give the - * rest of our timeslice to the lock holder. - * - * So that we can tell which virtual processor is holding a lock, - * we put 0x80000000 | smp_processor_id() in the lock when it is - * held. Conveniently, we have a word in the paca that holds this - * value. - */ - -#if defined(CONFIG_PPC_SPLPAR) -/* We only yield to the hypervisor if we are in shared processor mode */ -void splpar_spin_yield(arch_spinlock_t *lock); -void splpar_rw_yield(arch_rwlock_t *lock); -#else /* SPLPAR */ -static inline void splpar_spin_yield(arch_spinlock_t *lock) {}; -static inline void splpar_rw_yield(arch_rwlock_t *lock) {}; -#endif - -static inline void spin_yield(arch_spinlock_t *lock) -{ - if (is_shared_processor()) - splpar_spin_yield(lock); - else - barrier(); -} - -static inline void rw_yield(arch_rwlock_t *lock) -{ - if (is_shared_processor()) - splpar_rw_yield(lock); - else - barrier(); -} - -static inline void arch_spin_lock(arch_spinlock_t *lock) -{ - while (1) { - if (likely(__arch_spin_trylock(lock) == 0)) - break; - do { - HMT_low(); - if (is_shared_processor()) - splpar_spin_yield(lock); - } while (unlikely(lock->slock != 0)); - HMT_medium(); - } -} - -static inline -void arch_spin_lock_flags(arch_spinlock_t *lock, unsigned long flags) -{ - unsigned long flags_dis; - - while (1) { - if (likely(__arch_spin_trylock(lock) == 0)) - break; - local_save_flags(flags_dis); - local_irq_restore(flags); - do { - HMT_low(); - if (is_shared_processor()) - splpar_spin_yield(lock); - } while (unlikely(lock->slock != 0)); - HMT_medium(); - local_irq_restore(flags_dis); - } -} -#define arch_spin_lock_flags arch_spin_lock_flags - -static inline void arch_spin_unlock(arch_spinlock_t *lock) -{ - __asm__ __volatile__("# arch_spin_unlock\n\t" - PPC_RELEASE_BARRIER: : :"memory"); - lock->slock = 0; -} - -/* - * 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. - */ - -#ifdef CONFIG_PPC64 -#define __DO_SIGN_EXTEND "extsw %0,%0\n" -#define WRLOCK_TOKEN LOCK_TOKEN /* it's negative */ -#else -#define __DO_SIGN_EXTEND -#define WRLOCK_TOKEN (-1) -#endif - -/* - * This returns the old value in the lock + 1, - * so we got a read lock if the return value is > 0. - */ -static inline long __arch_read_trylock(arch_rwlock_t *rw) -{ - long tmp; - - __asm__ __volatile__( -"1: " PPC_LWARX(%0,0,%1,1) "\n" - __DO_SIGN_EXTEND -" addic. %0,%0,1\n\ - ble- 2f\n" -" stwcx. %0,0,%1\n\ - bne- 1b\n" - PPC_ACQUIRE_BARRIER -"2:" : "=&r" (tmp) - : "r" (&rw->lock) - : "cr0", "xer", "memory"); - - return tmp; -} - -/* - * This returns the old value in the lock, - * so we got the write lock if the return value is 0. - */ -static inline long __arch_write_trylock(arch_rwlock_t *rw) -{ - long tmp, token; - - token = WRLOCK_TOKEN; - __asm__ __volatile__( -"1: " PPC_LWARX(%0,0,%2,1) "\n\ - cmpwi 0,%0,0\n\ - bne- 2f\n" -" stwcx. %1,0,%2\n\ - bne- 1b\n" - PPC_ACQUIRE_BARRIER -"2:" : "=&r" (tmp) - : "r" (token), "r" (&rw->lock) - : "cr0", "memory"); - - return tmp; -} - -static inline void arch_read_lock(arch_rwlock_t *rw) -{ - while (1) { - if (likely(__arch_read_trylock(rw) > 0)) - break; - do { - HMT_low(); - if (is_shared_processor()) - splpar_rw_yield(rw); - } while (unlikely(rw->lock < 0)); - HMT_medium(); - } -} - -static inline void arch_write_lock(arch_rwlock_t *rw) -{ - while (1) { - if (likely(__arch_write_trylock(rw) == 0)) - break; - do { - HMT_low(); - if (is_shared_processor()) - splpar_rw_yield(rw); - } while (unlikely(rw->lock != 0)); - HMT_medium(); - } -} - -static inline int arch_read_trylock(arch_rwlock_t *rw) -{ - return __arch_read_trylock(rw) > 0; -} - -static inline int arch_write_trylock(arch_rwlock_t *rw) -{ - return __arch_write_trylock(rw) == 0; -} - -static inline void arch_read_unlock(arch_rwlock_t *rw) -{ - long tmp; - - __asm__ __volatile__( - "# read_unlock\n\t" - PPC_RELEASE_BARRIER -"1: lwarx %0,0,%1\n\ - addic %0,%0,-1\n" -" stwcx. %0,0,%1\n\ - bne- 1b" - : "=&r"(tmp) - : "r"(&rw->lock) - : "cr0", "xer", "memory"); -} - -static inline void arch_write_unlock(arch_rwlock_t *rw) -{ - __asm__ __volatile__("# write_unlock\n\t" - PPC_RELEASE_BARRIER: : :"memory"); - rw->lock = 0; -} - -#define arch_spin_relax(lock) spin_yield(lock) -#define arch_read_relax(lock) rw_yield(lock) -#define arch_write_relax(lock) rw_yield(lock) - -/* See include/linux/spinlock.h */ -#define smp_mb__after_spinlock() smp_mb() +#include <asm/simple_spinlock.h> #endif /* __KERNEL__ */ #endif /* __ASM_SPINLOCK_H */ diff --git a/arch/powerpc/include/asm/spinlock_types.h b/arch/powerpc/include/asm/spinlock_types.h index 87adaf13b7e8..3906f52dae65 100644 --- a/arch/powerpc/include/asm/spinlock_types.h +++ b/arch/powerpc/include/asm/spinlock_types.h @@ -6,16 +6,6 @@ # error "please don't include this file directly" #endif -typedef struct { - volatile unsigned int slock; -} arch_spinlock_t; - -#define __ARCH_SPIN_LOCK_UNLOCKED { 0 } - -typedef struct { - volatile signed int lock; -} arch_rwlock_t; - -#define __ARCH_RW_LOCK_UNLOCKED { 0 } +#include <asm/simple_spinlock_types.h> #endif -- 2.23.0