Commit a3a85a76 authored by Richard Weinberger's avatar Richard Weinberger
Browse files

um: Disintegrate asm/system.h 



Signed-off-by: default avatarRichard Weinberger <richard@nod.at>
Reported-by: default avatarToralf Förster <toralf.foerster@gmx.de>
CC: dhowells@redhat.com
parent d824d063

arch/um/drivers/mconsole_kern.c

+1 −0
Original line number Diff line number Diff line
@@ -22,6 +22,7 @@ 
#include <linux/workqueue.h>

#include <linux/mutex.h>

#include <asm/uaccess.h>

#include <asm/switch_to.h>



#include "init.h"

#include "irq_kern.h"

arch/um/include/asm/Kbuild

+1 −1
Original line number Diff line number Diff line 
generic-y += bug.h cputime.h device.h emergency-restart.h futex.h hardirq.h

generic-y += hw_irq.h irq_regs.h kdebug.h percpu.h sections.h topology.h xor.h

generic-y += ftrace.h pci.h io.h param.h delay.h mutex.h current.h
 
generic-y += ftrace.h pci.h io.h param.h delay.h mutex.h current.h exec.h

arch/x86/um/asm/system.h→arch/x86/um/asm/barrier.h

+75 −0
Original line number Diff line number Diff line 
#ifndef _ASM_X86_SYSTEM_H_

#define _ASM_X86_SYSTEM_H_

#ifndef _ASM_UM_BARRIER_H_

#define _ASM_UM_BARRIER_H_



#include <asm/asm.h>

#include <asm/segment.h>
@@ -10,111 +10,54 @@ 
#include <linux/kernel.h>

#include <linux/irqflags.h>



/* entries in ARCH_DLINFO: */

#ifdef CONFIG_IA32_EMULATION

# define AT_VECTOR_SIZE_ARCH 2

#else

# define AT_VECTOR_SIZE_ARCH 1

#endif



extern unsigned long arch_align_stack(unsigned long sp);



void default_idle(void);



/*

 * Force strict CPU ordering.

 * And yes, this is required on UP too when we're talking

 * to devices.

 */

#ifdef CONFIG_X86_32

/*

 * Some non-Intel clones support out of order store. wmb() ceases to be a

 * nop for these.

 */



#define mb()	alternative("lock; addl $0,0(%%esp)", "mfence", X86_FEATURE_XMM2)

#define rmb()	alternative("lock; addl $0,0(%%esp)", "lfence", X86_FEATURE_XMM2)

#define wmb()	alternative("lock; addl $0,0(%%esp)", "sfence", X86_FEATURE_XMM)

#else



#else /* CONFIG_X86_32 */



#define mb()	asm volatile("mfence" : : : "memory")

#define rmb()	asm volatile("lfence" : : : "memory")

#define wmb()	asm volatile("sfence" : : : "memory")

#endif



/**

 * read_barrier_depends - Flush all pending reads that subsequents reads

 * depend on.

 *

 * No data-dependent reads from memory-like regions are ever reordered

 * over this barrier.  All reads preceding this primitive are guaranteed

 * to access memory (but not necessarily other CPUs' caches) before any

 * reads following this primitive that depend on the data return by

 * any of the preceding reads.  This primitive is much lighter weight than

 * rmb() on most CPUs, and is never heavier weight than is

 * rmb().

 *

 * These ordering constraints are respected by both the local CPU

 * and the compiler.

 *

 * Ordering is not guaranteed by anything other than these primitives,

 * not even by data dependencies.  See the documentation for

 * memory_barrier() for examples and URLs to more information.

 *

 * For example, the following code would force ordering (the initial

 * value of "a" is zero, "b" is one, and "p" is "&a"):

 *

 * <programlisting>

 *	CPU 0				CPU 1

 *

 *	b = 2;

 *	memory_barrier();

 *	p = &b;				q = p;

 *					read_barrier_depends();

 *					d = *q;

 * </programlisting>

 *

 * because the read of "*q" depends on the read of "p" and these

 * two reads are separated by a read_barrier_depends().  However,

 * the following code, with the same initial values for "a" and "b":

 *

 * <programlisting>

 *	CPU 0				CPU 1

 *

 *	a = 2;

 *	memory_barrier();

 *	b = 3;				y = b;

 *					read_barrier_depends();

 *					x = a;

 * </programlisting>

 *

 * does not enforce ordering, since there is no data dependency between

 * the read of "a" and the read of "b".  Therefore, on some CPUs, such

 * as Alpha, "y" could be set to 3 and "x" to 0.  Use rmb()

 * in cases like this where there are no data dependencies.

 **/

#endif /* CONFIG_X86_32 */



#define read_barrier_depends()	do { } while (0)



#ifdef CONFIG_SMP



#define smp_mb()	mb()

#ifdef CONFIG_X86_PPRO_FENCE

#define smp_rmb()	rmb()

#else

#else /* CONFIG_X86_PPRO_FENCE */

#define smp_rmb()	barrier()

#endif

#endif /* CONFIG_X86_PPRO_FENCE */



#ifdef CONFIG_X86_OOSTORE

#define smp_wmb()	wmb()

#else

#else /* CONFIG_X86_OOSTORE */

#define smp_wmb()	barrier()

#endif

#endif /* CONFIG_X86_OOSTORE */



#define smp_read_barrier_depends()	read_barrier_depends()

#define set_mb(var, value) do { (void)xchg(&var, value); } while (0)

#else



#else /* CONFIG_SMP */



#define smp_mb()	barrier()

#define smp_rmb()	barrier()

#define smp_wmb()	barrier()

#define smp_read_barrier_depends()	do { } while (0)

#define set_mb(var, value) do { var = value; barrier(); } while (0)

#endif



#endif /* CONFIG_SMP */



/*

 * Stop RDTSC speculation. This is needed when you need to use RDTSC
@@ -129,7 +72,4 @@ static inline void rdtsc_barrier(void) 
	alternative(ASM_NOP3, "lfence", X86_FEATURE_LFENCE_RDTSC);

}



extern void *_switch_to(void *prev, void *next, void *last);

#define switch_to(prev, next, last) prev = _switch_to(prev, next, last)



#endif

arch/x86/um/asm/switch_to.h

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+7 −0
Original line number Diff line number Diff line 
#ifndef _ASM_UM_SWITCH_TO_H_

#define _ASM_UM_SWITCH_TO_H_



extern void *_switch_to(void *prev, void *next, void *last);

#define switch_to(prev, next, last) prev = _switch_to(prev, next, last)



#endif