[urcu.git] / arch_x86.h

#ifndef _ARCH_X86_H
#define _ARCH_X86_H

/*
 * arch_x86.h: trivial definitions for the x86 architecture.
 *
 * Copyright (c) 2009 Paul E. McKenney, IBM Corporation.
 * Copyright (c) 2009 Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
*
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include <compiler.h>
#include <arch_atomic.h>

/* Assume P4 or newer */
#define CONFIG_HAVE_FENCE 1
#define CONFIG_HAVE_MEM_COHERENCY

#ifndef BITS_PER_LONG
#define BITS_PER_LONG	(__SIZEOF_LONG__ * 8)
#endif

#ifdef CONFIG_HAVE_FENCE
#define mb()    asm volatile("mfence":::"memory")
#define rmb()   asm volatile("lfence":::"memory")
#define wmb()   asm volatile("sfence"::: "memory")
#else
/*
 * Some non-Intel clones support out of order store. wmb() ceases to be a
 * nop for these.
 */
#define mb()    asm volatile("lock; addl $0,0(%%esp)":::"memory")
#define rmb()   asm volatile("lock; addl $0,0(%%esp)":::"memory")
#define wmb()   asm volatile("lock; addl $0,0(%%esp)"::: "memory")
#endif

/*
 * Architectures without cache coherency need something like the following:
 *
 * #define mb()		mc()
 * #define rmb()	rmc()
 * #define wmb()	wmc()
 * #define mc()		arch_cache_flush()
 * #define rmc()	arch_cache_flush_read()
 * #define wmc()	arch_cache_flush_write()
 */

#define mc()	barrier()
#define rmc()	barrier()
#define wmc()	barrier()

/* Assume SMP machine, given we don't have this information */
#define CONFIG_SMP 1

#ifdef CONFIG_SMP
#define smp_mb()	mb()
#define smp_rmb()	rmb()
#define smp_wmb()	wmb()
#define smp_mc()	mc()
#define smp_rmc()	rmc()
#define smp_wmc()	wmc()
#else
#define smp_mb()	barrier()
#define smp_rmb()	barrier()
#define smp_wmb()	barrier()
#define smp_mc()	barrier()
#define smp_rmc()	barrier()
#define smp_wmc()	barrier()
#endif

/* Nop everywhere except on alpha. */
#define smp_read_barrier_depends()

static inline void rep_nop(void)
{
	asm volatile("rep; nop" : : : "memory");
}

static inline void cpu_relax(void)
{
	rep_nop();
}

/*
 * Serialize core instruction execution. Also acts as a compiler barrier.
 */
static inline void sync_core(void)
{
	asm volatile("cpuid" : : : "memory", "eax", "ebx", "ecx", "edx");
}

#define rdtscll(val)							  \
	do {						  		  \
	     unsigned int __a, __d;					  \
	     asm volatile("rdtsc" : "=a" (__a), "=d" (__d));		  \
	     (val) = ((unsigned long long)__a)				  \
			| (((unsigned long long)__d) << 32);		  \
	} while(0)

typedef unsigned long long cycles_t;

static inline cycles_t get_cycles(void)
{
        cycles_t ret = 0;

        rdtscll(ret);
        return ret;
}

#endif /* _ARCH_X86_H */
Commit	Line	Data
	1	#ifndef _ARCH_X86_H
	2	#define _ARCH_X86_H
	3
	4	/*
	5	* arch_x86.h: trivial definitions for the x86 architecture.
	6	*
	7	* Copyright (c) 2009 Paul E. McKenney, IBM Corporation.
	8	* Copyright (c) 2009 Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
	9	*
	10	* This library is free software; you can redistribute it and/or
	11	* modify it under the terms of the GNU Lesser General Public
	12	* License as published by the Free Software Foundation; either
	13	* version 2.1 of the License, or (at your option) any later version.
	14	*
	15	* This library is distributed in the hope that it will be useful,
	16	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	17	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	18	* Lesser General Public License for more details.
	19	*
	20	* You should have received a copy of the GNU Lesser General Public
	21	* License along with this library; if not, write to the Free Software
	22	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
	23	*/
	24
	25	#include <compiler.h>
	26	#include <arch_atomic.h>
	27
	28	/* Assume P4 or newer */
	29	#define CONFIG_HAVE_FENCE 1
	30	#define CONFIG_HAVE_MEM_COHERENCY
	31
	32	#ifndef BITS_PER_LONG
	33	#define BITS_PER_LONG (__SIZEOF_LONG__ * 8)
	34	#endif
	35
	36	#ifdef CONFIG_HAVE_FENCE
	37	#define mb() asm volatile("mfence":::"memory")
	38	#define rmb() asm volatile("lfence":::"memory")
	39	#define wmb() asm volatile("sfence"::: "memory")
	40	#else
	41	/*
	42	* Some non-Intel clones support out of order store. wmb() ceases to be a
	43	* nop for these.
	44	*/
	45	#define mb() asm volatile("lock; addl $0,0(%%esp)":::"memory")
	46	#define rmb() asm volatile("lock; addl $0,0(%%esp)":::"memory")
	47	#define wmb() asm volatile("lock; addl $0,0(%%esp)"::: "memory")
	48	#endif
	49
	50	/*
	51	* Architectures without cache coherency need something like the following:
	52	*
	53	* #define mb() mc()
	54	* #define rmb() rmc()
	55	* #define wmb() wmc()
	56	* #define mc() arch_cache_flush()
	57	* #define rmc() arch_cache_flush_read()
	58	* #define wmc() arch_cache_flush_write()
	59	*/
	60
	61	#define mc() barrier()
	62	#define rmc() barrier()
	63	#define wmc() barrier()
	64
	65	/* Assume SMP machine, given we don't have this information */
	66	#define CONFIG_SMP 1
	67
	68	#ifdef CONFIG_SMP
	69	#define smp_mb() mb()
	70	#define smp_rmb() rmb()
	71	#define smp_wmb() wmb()
	72	#define smp_mc() mc()
	73	#define smp_rmc() rmc()
	74	#define smp_wmc() wmc()
	75	#else
	76	#define smp_mb() barrier()
	77	#define smp_rmb() barrier()
	78	#define smp_wmb() barrier()
	79	#define smp_mc() barrier()
	80	#define smp_rmc() barrier()
	81	#define smp_wmc() barrier()
	82	#endif
	83
	84	/* Nop everywhere except on alpha. */
	85	#define smp_read_barrier_depends()
	86
	87	static inline void rep_nop(void)
	88	{
	89	asm volatile("rep; nop" : : : "memory");
	90	}
	91
	92	static inline void cpu_relax(void)
	93	{
	94	rep_nop();
	95	}
	96
	97	/*
	98	* Serialize core instruction execution. Also acts as a compiler barrier.
	99	*/
	100	static inline void sync_core(void)
	101	{
	102	asm volatile("cpuid" : : : "memory", "eax", "ebx", "ecx", "edx");
	103	}
	104
	105	#define rdtscll(val) \
	106	do { \
	107	unsigned int __a, __d; \
	108	asm volatile("rdtsc" : "=a" (__a), "=d" (__d)); \
	109	(val) = ((unsigned long long)__a) \
	110	\| (((unsigned long long)__d) << 32); \
	111	} while(0)
	112
	113	typedef unsigned long long cycles_t;
	114
	115	static inline cycles_t get_cycles(void)
	116	{
	117	cycles_t ret = 0;
	118
	119	rdtscll(ret);
	120	return ret;
	121	}
	122
	123	#endif /* _ARCH_X86_H */