#ifndef TCMALLOC_INTERNAL_SPINLOCK_H__
#define TCMALLOC_INTERNAL_SPINLOCK_H__
#include "config.h"
#include <time.h>
#include <sched.h>
#if HAVE(STDINT_H)
#include <stdint.h>
#elif HAVE(INTTYPES_H)
#include <inttypes.h>
#else
#include <sys/types.h>
#endif
#include <stdlib.h>
#if (PLATFORM(X86) || PLATFORM(PPC)) && COMPILER(GCC)
static void TCMalloc_SlowLock(volatile unsigned int* lockword);
struct TCMalloc_SpinLock {
volatile unsigned int private_lockword_;
inline void Init() { private_lockword_ = 0; }
inline void Finalize() { }
inline void Lock() {
int r;
#if PLATFORM(X86)
__asm__ __volatile__
("xchgl %0, %1"
: "=r"(r), "=m"(private_lockword_)
: "0"(1), "m"(private_lockword_)
: "memory");
#else
volatile unsigned int *lockword_ptr = &private_lockword_;
__asm__ __volatile__
("1: lwarx %0, 0, %1\n\t"
"stwcx. %2, 0, %1\n\t"
"bne- 1b\n\t"
"isync"
: "=&r" (r), "=r" (lockword_ptr)
: "r" (1), "1" (lockword_ptr)
: "memory");
#endif
if (r) TCMalloc_SlowLock(&private_lockword_);
}
inline void Unlock() {
#if PLATFORM(X86)
__asm__ __volatile__
("movl $0, %0"
: "=m"(private_lockword_)
: "m" (private_lockword_)
: "memory");
#else
__asm__ __volatile__
("isync\n\t"
"eieio\n\t"
"stw %1, %0"
: "=o" (private_lockword_)
: "r" (0)
: "memory");
#endif
}
};
#define SPINLOCK_INITIALIZER { 0 }
static void TCMalloc_SlowLock(volatile unsigned int* lockword) {
sched_yield(); while (true) {
int r;
#if PLATFORM(X86)
__asm__ __volatile__
("xchgl %0, %1"
: "=r"(r), "=m"(*lockword)
: "0"(1), "m"(*lockword)
: "memory");
#else
int tmp = 1;
__asm__ __volatile__
("1: lwarx %0, 0, %1\n\t"
"stwcx. %2, 0, %1\n\t"
"bne- 1b\n\t"
"isync"
: "=&r" (r), "=r" (lockword)
: "r" (tmp), "1" (lockword)
: "memory");
#endif
if (!r) {
return;
}
struct timespec tm;
tm.tv_sec = 0;
tm.tv_nsec = 2000001;
nanosleep(&tm, NULL);
}
}
#else
#include <pthread.h>
struct TCMalloc_SpinLock {
pthread_mutex_t private_lock_;
inline void Init() {
if (pthread_mutex_init(&private_lock_, NULL) != 0) abort();
}
inline void Finalize() {
if (pthread_mutex_destroy(&private_lock_) != 0) abort();
}
inline void Lock() {
if (pthread_mutex_lock(&private_lock_) != 0) abort();
}
inline void Unlock() {
if (pthread_mutex_unlock(&private_lock_) != 0) abort();
}
};
#define SPINLOCK_INITIALIZER { PTHREAD_MUTEX_INITIALIZER }
#endif
class TCMalloc_SpinLockHolder {
private:
TCMalloc_SpinLock* lock_;
public:
inline explicit TCMalloc_SpinLockHolder(TCMalloc_SpinLock* l)
: lock_(l) { l->Lock(); }
inline ~TCMalloc_SpinLockHolder() { lock_->Unlock(); }
};
typedef TCMalloc_SpinLock SpinLock;
typedef TCMalloc_SpinLockHolder SpinLockHolder;
#endif // TCMALLOC_INTERNAL_SPINLOCK_H__