85 lines
1.8 KiB
C
85 lines
1.8 KiB
C
/*
|
|
* Excerpted from Linux 3.0: arch/x86/include/asm/spinlock.h
|
|
*/
|
|
#ifndef __HEADER_X86_COMMON_ARCH_LOCK
|
|
#define __HEADER_X86_COMMON_ARCH_LOCK
|
|
|
|
#include <ihk/cpu.h>
|
|
|
|
//#define DEBUG_SPINLOCK
|
|
|
|
#ifdef DEBUG_SPINLOCK
|
|
int __kprintf(const char *format, ...);
|
|
#endif
|
|
|
|
typedef int aal_spinlock_t;
|
|
|
|
#define AAL_STATIC_SPINLOCK_FUNCS
|
|
|
|
static void aal_mc_spinlock_init(aal_spinlock_t *lock)
|
|
{
|
|
*lock = 0;
|
|
}
|
|
#define SPIN_LOCK_UNLOCKED 0
|
|
|
|
static unsigned long aal_mc_spinlock_lock(aal_spinlock_t *lock)
|
|
{
|
|
int inc = 0x00010000;
|
|
int tmp;
|
|
unsigned long flags;
|
|
|
|
flags = cpu_disable_interrupt_save();
|
|
|
|
#if 0
|
|
asm volatile("lock ; xaddl %0, %1\n"
|
|
"movzwl %w0, %2\n\t"
|
|
"shrl $16, %0\n\t"
|
|
"1:\t"
|
|
"cmpl %0, %2\n\t"
|
|
"je 2f\n\t"
|
|
"rep ; nop\n\t"
|
|
"movzwl %1, %2\n\t"
|
|
"jmp 1b\n"
|
|
"2:"
|
|
: "+Q" (inc), "+m" (*lock), "=r" (tmp) : : "memory", "cc");
|
|
#endif
|
|
|
|
#ifdef DEBUG_SPINLOCK
|
|
__kprintf("[%d] trying to grab lock: 0x%lX\n",
|
|
aal_mc_get_processor_id(), lock);
|
|
#endif
|
|
asm volatile("lock; xaddl %0, %1\n"
|
|
"movzwl %w0, %2\n\t"
|
|
"shrl $16, %0\n\t"
|
|
"1:\t"
|
|
"cmpl %0, %2\n\t"
|
|
"je 2f\n\t"
|
|
"rep ; nop\n\t"
|
|
"movzwl %1, %2\n\t"
|
|
/* don't need lfence here, because loads are in-order */
|
|
"jmp 1b\n"
|
|
"2:"
|
|
: "+r" (inc), "+m" (*lock), "=&r" (tmp)
|
|
:
|
|
: "memory", "cc");
|
|
|
|
#ifdef DEBUG_SPINLOCK
|
|
__kprintf("[%d] holding lock: 0x%lX\n", aal_mc_get_processor_id(), lock);
|
|
#endif
|
|
|
|
return flags;
|
|
}
|
|
|
|
static void aal_mc_spinlock_unlock(aal_spinlock_t *lock, unsigned long flags)
|
|
{
|
|
asm volatile ("lock incw %0" : "+m"(*lock) : : "memory", "cc");
|
|
|
|
cpu_restore_interrupt(flags);
|
|
#ifdef DEBUG_SPINLOCK
|
|
__kprintf("[%d] released lock: 0x%lX\n", aal_mc_get_processor_id(), lock);
|
|
#endif
|
|
}
|
|
|
|
#endif
|
|
|