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Release 4.14 arch/m32r/include/asm/spinlock.h

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_M32R_SPINLOCK_H

#define _ASM_M32R_SPINLOCK_H

/*
 *  linux/include/asm-m32r/spinlock.h
 *
 *  M32R version:
 *    Copyright (C) 2001, 2002  Hitoshi Yamamoto
 *    Copyright (C) 2004  Hirokazu Takata <takata at linux-m32r.org>
 */

#include <linux/compiler.h>
#include <linux/atomic.h>
#include <asm/dcache_clear.h>
#include <asm/page.h>
#include <asm/barrier.h>
#include <asm/processor.h>

/*
 * Your basic SMP spinlocks, allowing only a single CPU anywhere
 *
 * (the type definitions are in asm/spinlock_types.h)
 *
 * Simple spin lock operations.  There are two variants, one clears IRQ's
 * on the local processor, one does not.
 *
 * We make no fairness assumptions. They have a cost.
 */


#define arch_spin_is_locked(x)		(*(volatile int *)(&(x)->slock) <= 0)

#define arch_spin_lock_flags(lock, flags) arch_spin_lock(lock)

/**
 * arch_spin_trylock - Try spin lock and return a result
 * @lock: Pointer to the lock variable
 *
 * arch_spin_trylock() tries to get the lock and returns a result.
 * On the m32r, the result value is 1 (= Success) or 0 (= Failure).
 */

static inline int arch_spin_trylock(arch_spinlock_t *lock) { int oldval; unsigned long tmp1, tmp2; /* * lock->slock : =1 : unlock * : <=0 : lock * { * oldval = lock->slock; <--+ need atomic operation * lock->slock = 0; <--+ * } */ __asm__ __volatile__ ( "# arch_spin_trylock \n\t" "ldi %1, #0; \n\t" "mvfc %2, psw; \n\t" "clrpsw #0x40 -> nop; \n\t" DCACHE_CLEAR("%0", "r6", "%3") "lock %0, @%3; \n\t" "unlock %1, @%3; \n\t" "mvtc %2, psw; \n\t" : "=&r" (oldval), "=&r" (tmp1), "=&r" (tmp2) : "r" (&lock->slock) : "memory" #ifdef CONFIG_CHIP_M32700_TS1 , "r6" #endif /* CONFIG_CHIP_M32700_TS1 */ ); return (oldval > 0); }

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PersonTokensPropCommitsCommitProp
Hirokazu Takata3692.31%360.00%
Thomas Gleixner37.69%240.00%
Total39100.00%5100.00%


static inline void arch_spin_lock(arch_spinlock_t *lock) { unsigned long tmp0, tmp1; /* * lock->slock : =1 : unlock * : <=0 : lock * * for ( ; ; ) { * lock->slock -= 1; <-- need atomic operation * if (lock->slock == 0) break; * for ( ; lock->slock <= 0 ; ); * } */ __asm__ __volatile__ ( "# arch_spin_lock \n\t" ".fillinsn \n" "1: \n\t" "mvfc %1, psw; \n\t" "clrpsw #0x40 -> nop; \n\t" DCACHE_CLEAR("%0", "r6", "%2") "lock %0, @%2; \n\t" "addi %0, #-1; \n\t" "unlock %0, @%2; \n\t" "mvtc %1, psw; \n\t" "bltz %0, 2f; \n\t" LOCK_SECTION_START(".balign 4 \n\t") ".fillinsn \n" "2: \n\t" "ld %0, @%2; \n\t" "bgtz %0, 1b; \n\t" "bra 2b; \n\t" LOCK_SECTION_END : "=&r" (tmp0), "=&r" (tmp1) : "r" (&lock->slock) : "memory" #ifdef CONFIG_CHIP_M32700_TS1 , "r6" #endif /* CONFIG_CHIP_M32700_TS1 */ ); }

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PersonTokensPropCommitsCommitProp
Hirokazu Takata2689.66%360.00%
Thomas Gleixner310.34%240.00%
Total29100.00%5100.00%


static inline void arch_spin_unlock(arch_spinlock_t *lock) { mb(); lock->slock = 1; }

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Hirokazu Takata1890.00%360.00%
Thomas Gleixner210.00%240.00%
Total20100.00%5100.00%

/* * 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. * * The inline assembly is non-obvious. Think about it. * * Changed to use the same technique as rw semaphores. See * semaphore.h for details. -ben */ /** * read_can_lock - would read_trylock() succeed? * @lock: the rwlock in question. */ #define arch_read_can_lock(x) ((int)(x)->lock > 0) /** * write_can_lock - would write_trylock() succeed? * @lock: the rwlock in question. */ #define arch_write_can_lock(x) ((x)->lock == RW_LOCK_BIAS)
static inline void arch_read_lock(arch_rwlock_t *rw) { unsigned long tmp0, tmp1; /* * rw->lock : >0 : unlock * : <=0 : lock * * for ( ; ; ) { * rw->lock -= 1; <-- need atomic operation * if (rw->lock >= 0) break; * rw->lock += 1; <-- need atomic operation * for ( ; rw->lock <= 0 ; ); * } */ __asm__ __volatile__ ( "# read_lock \n\t" ".fillinsn \n" "1: \n\t" "mvfc %1, psw; \n\t" "clrpsw #0x40 -> nop; \n\t" DCACHE_CLEAR("%0", "r6", "%2") "lock %0, @%2; \n\t" "addi %0, #-1; \n\t" "unlock %0, @%2; \n\t" "mvtc %1, psw; \n\t" "bltz %0, 2f; \n\t" LOCK_SECTION_START(".balign 4 \n\t") ".fillinsn \n" "2: \n\t" "clrpsw #0x40 -> nop; \n\t" DCACHE_CLEAR("%0", "r6", "%2") "lock %0, @%2; \n\t" "addi %0, #1; \n\t" "unlock %0, @%2; \n\t" "mvtc %1, psw; \n\t" ".fillinsn \n" "3: \n\t" "ld %0, @%2; \n\t" "bgtz %0, 1b; \n\t" "bra 3b; \n\t" LOCK_SECTION_END : "=&r" (tmp0), "=&r" (tmp1) : "r" (&rw->lock) : "memory" #ifdef CONFIG_CHIP_M32700_TS1 , "r6" #endif /* CONFIG_CHIP_M32700_TS1 */ ); }

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Hirokazu Takata2793.10%250.00%
Thomas Gleixner26.90%250.00%
Total29100.00%4100.00%


static inline void arch_write_lock(arch_rwlock_t *rw) { unsigned long tmp0, tmp1, tmp2; /* * rw->lock : =RW_LOCK_BIAS_STR : unlock * : !=RW_LOCK_BIAS_STR : lock * * for ( ; ; ) { * rw->lock -= RW_LOCK_BIAS_STR; <-- need atomic operation * if (rw->lock == 0) break; * rw->lock += RW_LOCK_BIAS_STR; <-- need atomic operation * for ( ; rw->lock != RW_LOCK_BIAS_STR ; ) ; * } */ __asm__ __volatile__ ( "# write_lock \n\t" "seth %1, #high(" RW_LOCK_BIAS_STR "); \n\t" "or3 %1, %1, #low(" RW_LOCK_BIAS_STR "); \n\t" ".fillinsn \n" "1: \n\t" "mvfc %2, psw; \n\t" "clrpsw #0x40 -> nop; \n\t" DCACHE_CLEAR("%0", "r7", "%3") "lock %0, @%3; \n\t" "sub %0, %1; \n\t" "unlock %0, @%3; \n\t" "mvtc %2, psw; \n\t" "bnez %0, 2f; \n\t" LOCK_SECTION_START(".balign 4 \n\t") ".fillinsn \n" "2: \n\t" "clrpsw #0x40 -> nop; \n\t" DCACHE_CLEAR("%0", "r7", "%3") "lock %0, @%3; \n\t" "add %0, %1; \n\t" "unlock %0, @%3; \n\t" "mvtc %2, psw; \n\t" ".fillinsn \n" "3: \n\t" "ld %0, @%3; \n\t" "beq %0, %1, 1b; \n\t" "bra 3b; \n\t" LOCK_SECTION_END : "=&r" (tmp0), "=&r" (tmp1), "=&r" (tmp2) : "r" (&rw->lock) : "memory" #ifdef CONFIG_CHIP_M32700_TS1 , "r7" #endif /* CONFIG_CHIP_M32700_TS1 */ ); }

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Hirokazu Takata2993.55%250.00%
Thomas Gleixner26.45%250.00%
Total31100.00%4100.00%


static inline void arch_read_unlock(arch_rwlock_t *rw) { unsigned long tmp0, tmp1; __asm__ __volatile__ ( "# read_unlock \n\t" "mvfc %1, psw; \n\t" "clrpsw #0x40 -> nop; \n\t" DCACHE_CLEAR("%0", "r6", "%2") "lock %0, @%2; \n\t" "addi %0, #1; \n\t" "unlock %0, @%2; \n\t" "mvtc %1, psw; \n\t" : "=&r" (tmp0), "=&r" (tmp1) : "r" (&rw->lock) : "memory" #ifdef CONFIG_CHIP_M32700_TS1 , "r6" #endif /* CONFIG_CHIP_M32700_TS1 */ ); }

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PersonTokensPropCommitsCommitProp
Hirokazu Takata2692.86%250.00%
Thomas Gleixner27.14%250.00%
Total28100.00%4100.00%


static inline void arch_write_unlock(arch_rwlock_t *rw) { unsigned long tmp0, tmp1, tmp2; __asm__ __volatile__ ( "# write_unlock \n\t" "seth %1, #high(" RW_LOCK_BIAS_STR "); \n\t" "or3 %1, %1, #low(" RW_LOCK_BIAS_STR "); \n\t" "mvfc %2, psw; \n\t" "clrpsw #0x40 -> nop; \n\t" DCACHE_CLEAR("%0", "r7", "%3") "lock %0, @%3; \n\t" "add %0, %1; \n\t" "unlock %0, @%3; \n\t" "mvtc %2, psw; \n\t" : "=&r" (tmp0), "=&r" (tmp1), "=&r" (tmp2) : "r" (&rw->lock) : "memory" #ifdef CONFIG_CHIP_M32700_TS1 , "r7" #endif /* CONFIG_CHIP_M32700_TS1 */ ); }

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PersonTokensPropCommitsCommitProp
Hirokazu Takata2893.33%250.00%
Thomas Gleixner26.67%250.00%
Total30100.00%4100.00%


static inline int arch_read_trylock(arch_rwlock_t *lock) { atomic_t *count = (atomic_t*)lock; if (atomic_dec_return(count) >= 0) return 1; atomic_inc(count); return 0; }

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Hirokazu Takata3995.12%250.00%
Thomas Gleixner24.88%250.00%
Total41100.00%4100.00%


static inline int arch_write_trylock(arch_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; }

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Hirokazu Takata4195.35%250.00%
Thomas Gleixner24.65%250.00%
Total43100.00%4100.00%

#define arch_read_lock_flags(lock, flags) arch_read_lock(lock) #define arch_write_lock_flags(lock, flags) arch_write_lock(lock) #define arch_spin_relax(lock) cpu_relax() #define arch_read_relax(lock) cpu_relax() #define arch_write_relax(lock) cpu_relax() #endif /* _ASM_M32R_SPINLOCK_H */

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PersonTokensPropCommitsCommitProp
Hirokazu Takata31279.39%426.67%
Thomas Gleixner338.40%426.67%
Martin Schwidefsky184.58%16.67%
Robin Holt143.56%16.67%
Peter Zijlstra61.53%16.67%
Ingo Molnar51.27%16.67%
David Howells30.76%16.67%
Greg Kroah-Hartman10.25%16.67%
Arun Sharma10.25%16.67%
Total393100.00%15100.00%
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