#ifndef _ASM_SPINLOCK_H
#define _ASM_SPINLOCK_H
-#include <linux/compiler.h>
-
-#include <asm/barrier.h>
#include <asm/processor.h>
#include <asm/qrwlock.h>
-#include <asm/compiler.h>
-#include <asm/war.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
- *
- * (the type definitions are in asm/spinlock_types.h)
- */
-
-
-/*
- * Ticket locks are conceptually two parts, 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.
- */
-
-static inline int arch_spin_is_locked(arch_spinlock_t *lock)
-{
- u32 counters = ACCESS_ONCE(lock->lock);
-
- return ((counters >> 16) ^ counters) & 0xffff;
-}
-
-static inline int arch_spin_value_unlocked(arch_spinlock_t lock)
-{
- return lock.h.serving_now == lock.h.ticket;
-}
-
-#define arch_spin_lock_flags(lock, flags) arch_spin_lock(lock)
-
-static inline void arch_spin_unlock_wait(arch_spinlock_t *lock)
-{
- u16 owner = READ_ONCE(lock->h.serving_now);
- smp_rmb();
- for (;;) {
- arch_spinlock_t tmp = READ_ONCE(*lock);
-
- if (tmp.h.serving_now == tmp.h.ticket ||
- tmp.h.serving_now != owner)
- break;
-
- cpu_relax();
- }
- smp_acquire__after_ctrl_dep();
-}
-
-static inline int arch_spin_is_contended(arch_spinlock_t *lock)
-{
- u32 counters = ACCESS_ONCE(lock->lock);
-
- return (((counters >> 16) - counters) & 0xffff) > 1;
-}
-#define arch_spin_is_contended arch_spin_is_contended
-
-static inline void arch_spin_lock(arch_spinlock_t *lock)
-{
- int my_ticket;
- int tmp;
- int inc = 0x10000;
-
- if (R10000_LLSC_WAR) {
- __asm__ __volatile__ (
- " .set push # arch_spin_lock \n"
- " .set noreorder \n"
- " \n"
- "1: ll %[ticket], %[ticket_ptr] \n"
- " addu %[my_ticket], %[ticket], %[inc] \n"
- " sc %[my_ticket], %[ticket_ptr] \n"
- " beqzl %[my_ticket], 1b \n"
- " nop \n"
- " srl %[my_ticket], %[ticket], 16 \n"
- " andi %[ticket], %[ticket], 0xffff \n"
- " bne %[ticket], %[my_ticket], 4f \n"
- " subu %[ticket], %[my_ticket], %[ticket] \n"
- "2: \n"
- " .subsection 2 \n"
- "4: andi %[ticket], %[ticket], 0xffff \n"
- " sll %[ticket], 5 \n"
- " \n"
- "6: bnez %[ticket], 6b \n"
- " subu %[ticket], 1 \n"
- " \n"
- " lhu %[ticket], %[serving_now_ptr] \n"
- " beq %[ticket], %[my_ticket], 2b \n"
- " subu %[ticket], %[my_ticket], %[ticket] \n"
- " b 4b \n"
- " subu %[ticket], %[ticket], 1 \n"
- " .previous \n"
- " .set pop \n"
- : [ticket_ptr] "+" GCC_OFF_SMALL_ASM() (lock->lock),
- [serving_now_ptr] "+m" (lock->h.serving_now),
- [ticket] "=&r" (tmp),
- [my_ticket] "=&r" (my_ticket)
- : [inc] "r" (inc));
- } else {
- __asm__ __volatile__ (
- " .set push # arch_spin_lock \n"
- " .set noreorder \n"
- " \n"
- "1: ll %[ticket], %[ticket_ptr] \n"
- " addu %[my_ticket], %[ticket], %[inc] \n"
- " sc %[my_ticket], %[ticket_ptr] \n"
- " beqz %[my_ticket], 1b \n"
- " srl %[my_ticket], %[ticket], 16 \n"
- " andi %[ticket], %[ticket], 0xffff \n"
- " bne %[ticket], %[my_ticket], 4f \n"
- " subu %[ticket], %[my_ticket], %[ticket] \n"
- "2: .insn \n"
- " .subsection 2 \n"
- "4: andi %[ticket], %[ticket], 0xffff \n"
- " sll %[ticket], 5 \n"
- " \n"
- "6: bnez %[ticket], 6b \n"
- " subu %[ticket], 1 \n"
- " \n"
- " lhu %[ticket], %[serving_now_ptr] \n"
- " beq %[ticket], %[my_ticket], 2b \n"
- " subu %[ticket], %[my_ticket], %[ticket] \n"
- " b 4b \n"
- " subu %[ticket], %[ticket], 1 \n"
- " .previous \n"
- " .set pop \n"
- : [ticket_ptr] "+" GCC_OFF_SMALL_ASM() (lock->lock),
- [serving_now_ptr] "+m" (lock->h.serving_now),
- [ticket] "=&r" (tmp),
- [my_ticket] "=&r" (my_ticket)
- : [inc] "r" (inc));
- }
-
- smp_llsc_mb();
-}
-
-static inline void arch_spin_unlock(arch_spinlock_t *lock)
-{
- unsigned int serving_now = lock->h.serving_now + 1;
- wmb();
- lock->h.serving_now = (u16)serving_now;
- nudge_writes();
-}
-
-static inline unsigned int arch_spin_trylock(arch_spinlock_t *lock)
-{
- int tmp, tmp2, tmp3;
- int inc = 0x10000;
-
- if (R10000_LLSC_WAR) {
- __asm__ __volatile__ (
- " .set push # arch_spin_trylock \n"
- " .set noreorder \n"
- " \n"
- "1: ll %[ticket], %[ticket_ptr] \n"
- " srl %[my_ticket], %[ticket], 16 \n"
- " andi %[now_serving], %[ticket], 0xffff \n"
- " bne %[my_ticket], %[now_serving], 3f \n"
- " addu %[ticket], %[ticket], %[inc] \n"
- " sc %[ticket], %[ticket_ptr] \n"
- " beqzl %[ticket], 1b \n"
- " li %[ticket], 1 \n"
- "2: \n"
- " .subsection 2 \n"
- "3: b 2b \n"
- " li %[ticket], 0 \n"
- " .previous \n"
- " .set pop \n"
- : [ticket_ptr] "+" GCC_OFF_SMALL_ASM() (lock->lock),
- [ticket] "=&r" (tmp),
- [my_ticket] "=&r" (tmp2),
- [now_serving] "=&r" (tmp3)
- : [inc] "r" (inc));
- } else {
- __asm__ __volatile__ (
- " .set push # arch_spin_trylock \n"
- " .set noreorder \n"
- " \n"
- "1: ll %[ticket], %[ticket_ptr] \n"
- " srl %[my_ticket], %[ticket], 16 \n"
- " andi %[now_serving], %[ticket], 0xffff \n"
- " bne %[my_ticket], %[now_serving], 3f \n"
- " addu %[ticket], %[ticket], %[inc] \n"
- " sc %[ticket], %[ticket_ptr] \n"
- " beqz %[ticket], 1b \n"
- " li %[ticket], 1 \n"
- "2: .insn \n"
- " .subsection 2 \n"
- "3: b 2b \n"
- " li %[ticket], 0 \n"
- " .previous \n"
- " .set pop \n"
- : [ticket_ptr] "+" GCC_OFF_SMALL_ASM() (lock->lock),
- [ticket] "=&r" (tmp),
- [my_ticket] "=&r" (tmp2),
- [now_serving] "=&r" (tmp3)
- : [inc] "r" (inc));
- }
-
- smp_llsc_mb();
-
- return tmp;
-}
+#include <asm/qspinlock.h>
#define arch_read_lock_flags(lock, flags) arch_read_lock(lock)
#define arch_write_lock_flags(lock, flags) arch_write_lock(lock)
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