linux_dsm_epyc7002/include/asm-ppc64/system.h
Anton Blanchard b2c0ab17ba [PATCH] ppc64: speedup cmpxchg
cmpxchg has the following code:

__typeof__(*(ptr)) _o_ = (o);
__typeof__(*(ptr)) _n_ = (n);

Unfortunately it makes gcc 4.0 store and load the variables to the stack.
Eg in atomic_dec_and_test we get:

  stw     r10,112(r1)
  stw     r9,116(r1)
  lwz     r9,112(r1)
  lwz     r0,116(r1)

x86 is just casting the values so do that instead. Also change __xchg*
and __cmpxchg* to take unsigned values, removing a few sign extensions.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-09-06 16:07:53 +10:00

306 lines
8.5 KiB
C

#ifndef __PPC64_SYSTEM_H
#define __PPC64_SYSTEM_H
/*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <linux/config.h>
#include <linux/compiler.h>
#include <asm/page.h>
#include <asm/processor.h>
#include <asm/hw_irq.h>
#include <asm/memory.h>
/*
* Memory barrier.
* The sync instruction guarantees that all memory accesses initiated
* by this processor have been performed (with respect to all other
* mechanisms that access memory). The eieio instruction is a barrier
* providing an ordering (separately) for (a) cacheable stores and (b)
* loads and stores to non-cacheable memory (e.g. I/O devices).
*
* mb() prevents loads and stores being reordered across this point.
* rmb() prevents loads being reordered across this point.
* wmb() prevents stores being reordered across this point.
* read_barrier_depends() prevents data-dependent loads being reordered
* across this point (nop on PPC).
*
* We have to use the sync instructions for mb(), since lwsync doesn't
* order loads with respect to previous stores. Lwsync is fine for
* rmb(), though.
* For wmb(), we use sync since wmb is used in drivers to order
* stores to system memory with respect to writes to the device.
* However, smp_wmb() can be a lighter-weight eieio barrier on
* SMP since it is only used to order updates to system memory.
*/
#define mb() __asm__ __volatile__ ("sync" : : : "memory")
#define rmb() __asm__ __volatile__ ("lwsync" : : : "memory")
#define wmb() __asm__ __volatile__ ("sync" : : : "memory")
#define read_barrier_depends() do { } while(0)
#define set_mb(var, value) do { var = value; smp_mb(); } while (0)
#define set_wmb(var, value) do { var = value; smp_wmb(); } while (0)
#ifdef CONFIG_SMP
#define smp_mb() mb()
#define smp_rmb() rmb()
#define smp_wmb() __asm__ __volatile__ ("eieio" : : : "memory")
#define smp_read_barrier_depends() read_barrier_depends()
#else
#define smp_mb() __asm__ __volatile__("": : :"memory")
#define smp_rmb() __asm__ __volatile__("": : :"memory")
#define smp_wmb() __asm__ __volatile__("": : :"memory")
#define smp_read_barrier_depends() do { } while(0)
#endif /* CONFIG_SMP */
#ifdef __KERNEL__
struct task_struct;
struct pt_regs;
#ifdef CONFIG_DEBUGGER
extern int (*__debugger)(struct pt_regs *regs);
extern int (*__debugger_ipi)(struct pt_regs *regs);
extern int (*__debugger_bpt)(struct pt_regs *regs);
extern int (*__debugger_sstep)(struct pt_regs *regs);
extern int (*__debugger_iabr_match)(struct pt_regs *regs);
extern int (*__debugger_dabr_match)(struct pt_regs *regs);
extern int (*__debugger_fault_handler)(struct pt_regs *regs);
#define DEBUGGER_BOILERPLATE(__NAME) \
static inline int __NAME(struct pt_regs *regs) \
{ \
if (unlikely(__ ## __NAME)) \
return __ ## __NAME(regs); \
return 0; \
}
DEBUGGER_BOILERPLATE(debugger)
DEBUGGER_BOILERPLATE(debugger_ipi)
DEBUGGER_BOILERPLATE(debugger_bpt)
DEBUGGER_BOILERPLATE(debugger_sstep)
DEBUGGER_BOILERPLATE(debugger_iabr_match)
DEBUGGER_BOILERPLATE(debugger_dabr_match)
DEBUGGER_BOILERPLATE(debugger_fault_handler)
#ifdef CONFIG_XMON
extern void xmon_init(int enable);
#endif
#else
static inline int debugger(struct pt_regs *regs) { return 0; }
static inline int debugger_ipi(struct pt_regs *regs) { return 0; }
static inline int debugger_bpt(struct pt_regs *regs) { return 0; }
static inline int debugger_sstep(struct pt_regs *regs) { return 0; }
static inline int debugger_iabr_match(struct pt_regs *regs) { return 0; }
static inline int debugger_dabr_match(struct pt_regs *regs) { return 0; }
static inline int debugger_fault_handler(struct pt_regs *regs) { return 0; }
#endif
extern int fix_alignment(struct pt_regs *regs);
extern void bad_page_fault(struct pt_regs *regs, unsigned long address,
int sig);
extern void show_regs(struct pt_regs * regs);
extern void low_hash_fault(struct pt_regs *regs, unsigned long address);
extern int die(const char *str, struct pt_regs *regs, long err);
extern int _get_PVR(void);
extern void giveup_fpu(struct task_struct *);
extern void disable_kernel_fp(void);
extern void flush_fp_to_thread(struct task_struct *);
extern void enable_kernel_fp(void);
extern void giveup_altivec(struct task_struct *);
extern void disable_kernel_altivec(void);
extern void enable_kernel_altivec(void);
extern int emulate_altivec(struct pt_regs *);
extern void cvt_fd(float *from, double *to, unsigned long *fpscr);
extern void cvt_df(double *from, float *to, unsigned long *fpscr);
#ifdef CONFIG_ALTIVEC
extern void flush_altivec_to_thread(struct task_struct *);
#else
static inline void flush_altivec_to_thread(struct task_struct *t)
{
}
#endif
extern int mem_init_done; /* set on boot once kmalloc can be called */
/* EBCDIC -> ASCII conversion for [0-9A-Z] on iSeries */
extern unsigned char e2a(unsigned char);
extern struct task_struct *__switch_to(struct task_struct *,
struct task_struct *);
#define switch_to(prev, next, last) ((last) = __switch_to((prev), (next)))
struct thread_struct;
extern struct task_struct * _switch(struct thread_struct *prev,
struct thread_struct *next);
static inline int __is_processor(unsigned long pv)
{
unsigned long pvr;
asm("mfspr %0, 0x11F" : "=r" (pvr));
return(PVR_VER(pvr) == pv);
}
/*
* Atomic exchange
*
* Changes the memory location '*ptr' to be val and returns
* the previous value stored there.
*
* Inline asm pulled from arch/ppc/kernel/misc.S so ppc64
* is more like most of the other architectures.
*/
static __inline__ unsigned long
__xchg_u32(volatile unsigned int *m, unsigned long val)
{
unsigned long dummy;
__asm__ __volatile__(
EIEIO_ON_SMP
"1: lwarx %0,0,%3 # __xchg_u32\n\
stwcx. %2,0,%3\n\
2: bne- 1b"
ISYNC_ON_SMP
: "=&r" (dummy), "=m" (*m)
: "r" (val), "r" (m)
: "cc", "memory");
return (dummy);
}
static __inline__ unsigned long
__xchg_u64(volatile long *m, unsigned long val)
{
unsigned long dummy;
__asm__ __volatile__(
EIEIO_ON_SMP
"1: ldarx %0,0,%3 # __xchg_u64\n\
stdcx. %2,0,%3\n\
2: bne- 1b"
ISYNC_ON_SMP
: "=&r" (dummy), "=m" (*m)
: "r" (val), "r" (m)
: "cc", "memory");
return (dummy);
}
/*
* This function doesn't exist, so you'll get a linker error
* if something tries to do an invalid xchg().
*/
extern void __xchg_called_with_bad_pointer(void);
static __inline__ unsigned long
__xchg(volatile void *ptr, unsigned long x, unsigned int size)
{
switch (size) {
case 4:
return __xchg_u32(ptr, x);
case 8:
return __xchg_u64(ptr, x);
}
__xchg_called_with_bad_pointer();
return x;
}
#define xchg(ptr,x) \
({ \
__typeof__(*(ptr)) _x_ = (x); \
(__typeof__(*(ptr))) __xchg((ptr), (unsigned long)_x_, sizeof(*(ptr))); \
})
#define tas(ptr) (xchg((ptr),1))
#define __HAVE_ARCH_CMPXCHG 1
static __inline__ unsigned long
__cmpxchg_u32(volatile unsigned int *p, unsigned long old, unsigned long new)
{
unsigned int prev;
__asm__ __volatile__ (
EIEIO_ON_SMP
"1: lwarx %0,0,%2 # __cmpxchg_u32\n\
cmpw 0,%0,%3\n\
bne- 2f\n\
stwcx. %4,0,%2\n\
bne- 1b"
ISYNC_ON_SMP
"\n\
2:"
: "=&r" (prev), "=m" (*p)
: "r" (p), "r" (old), "r" (new), "m" (*p)
: "cc", "memory");
return prev;
}
static __inline__ unsigned long
__cmpxchg_u64(volatile long *p, unsigned long old, unsigned long new)
{
unsigned long prev;
__asm__ __volatile__ (
EIEIO_ON_SMP
"1: ldarx %0,0,%2 # __cmpxchg_u64\n\
cmpd 0,%0,%3\n\
bne- 2f\n\
stdcx. %4,0,%2\n\
bne- 1b"
ISYNC_ON_SMP
"\n\
2:"
: "=&r" (prev), "=m" (*p)
: "r" (p), "r" (old), "r" (new), "m" (*p)
: "cc", "memory");
return prev;
}
/* This function doesn't exist, so you'll get a linker error
if something tries to do an invalid cmpxchg(). */
extern void __cmpxchg_called_with_bad_pointer(void);
static __inline__ unsigned long
__cmpxchg(volatile void *ptr, unsigned long old, unsigned long new,
unsigned int size)
{
switch (size) {
case 4:
return __cmpxchg_u32(ptr, old, new);
case 8:
return __cmpxchg_u64(ptr, old, new);
}
__cmpxchg_called_with_bad_pointer();
return old;
}
#define cmpxchg(ptr,o,n)\
((__typeof__(*(ptr)))__cmpxchg((ptr),(unsigned long)(o),\
(unsigned long)(n),sizeof(*(ptr))))
/*
* We handle most unaligned accesses in hardware. On the other hand
* unaligned DMA can be very expensive on some ppc64 IO chips (it does
* powers of 2 writes until it reaches sufficient alignment).
*
* Based on this we disable the IP header alignment in network drivers.
*/
#define NET_IP_ALIGN 0
#define arch_align_stack(x) (x)
extern unsigned long reloc_offset(void);
#endif /* __KERNEL__ */
#endif