linux/arch/s390/include/asm/system.h
Heiko Carstens 189b93d00f [S390] switch_to: get rid of prev == next check
schedule() makes sure that prev != next before calling switch_to().
Therefore remove the redundant check.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-10-25 16:10:16 +02:00

480 lines
11 KiB
C

/*
* Copyright IBM Corp. 1999, 2009
*
* Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
*/
#ifndef __ASM_SYSTEM_H
#define __ASM_SYSTEM_H
#include <linux/kernel.h>
#include <linux/errno.h>
#include <asm/types.h>
#include <asm/ptrace.h>
#include <asm/setup.h>
#include <asm/processor.h>
#include <asm/lowcore.h>
#ifdef __KERNEL__
struct task_struct;
extern struct task_struct *__switch_to(void *, void *);
static inline void save_fp_regs(s390_fp_regs *fpregs)
{
asm volatile(
" std 0,%O0+8(%R0)\n"
" std 2,%O0+24(%R0)\n"
" std 4,%O0+40(%R0)\n"
" std 6,%O0+56(%R0)"
: "=Q" (*fpregs) : "Q" (*fpregs));
if (!MACHINE_HAS_IEEE)
return;
asm volatile(
" stfpc %0\n"
" std 1,%O0+16(%R0)\n"
" std 3,%O0+32(%R0)\n"
" std 5,%O0+48(%R0)\n"
" std 7,%O0+64(%R0)\n"
" std 8,%O0+72(%R0)\n"
" std 9,%O0+80(%R0)\n"
" std 10,%O0+88(%R0)\n"
" std 11,%O0+96(%R0)\n"
" std 12,%O0+104(%R0)\n"
" std 13,%O0+112(%R0)\n"
" std 14,%O0+120(%R0)\n"
" std 15,%O0+128(%R0)\n"
: "=Q" (*fpregs) : "Q" (*fpregs));
}
static inline void restore_fp_regs(s390_fp_regs *fpregs)
{
asm volatile(
" ld 0,%O0+8(%R0)\n"
" ld 2,%O0+24(%R0)\n"
" ld 4,%O0+40(%R0)\n"
" ld 6,%O0+56(%R0)"
: : "Q" (*fpregs));
if (!MACHINE_HAS_IEEE)
return;
asm volatile(
" lfpc %0\n"
" ld 1,%O0+16(%R0)\n"
" ld 3,%O0+32(%R0)\n"
" ld 5,%O0+48(%R0)\n"
" ld 7,%O0+64(%R0)\n"
" ld 8,%O0+72(%R0)\n"
" ld 9,%O0+80(%R0)\n"
" ld 10,%O0+88(%R0)\n"
" ld 11,%O0+96(%R0)\n"
" ld 12,%O0+104(%R0)\n"
" ld 13,%O0+112(%R0)\n"
" ld 14,%O0+120(%R0)\n"
" ld 15,%O0+128(%R0)\n"
: : "Q" (*fpregs));
}
static inline void save_access_regs(unsigned int *acrs)
{
asm volatile("stam 0,15,%0" : "=Q" (*acrs));
}
static inline void restore_access_regs(unsigned int *acrs)
{
asm volatile("lam 0,15,%0" : : "Q" (*acrs));
}
#define switch_to(prev,next,last) do { \
if (prev->mm) { \
save_fp_regs(&prev->thread.fp_regs); \
save_access_regs(&prev->thread.acrs[0]); \
} \
if (next->mm) { \
restore_fp_regs(&next->thread.fp_regs); \
restore_access_regs(&next->thread.acrs[0]); \
} \
prev = __switch_to(prev,next); \
} while (0)
extern void account_vtime(struct task_struct *, struct task_struct *);
extern void account_tick_vtime(struct task_struct *);
#ifdef CONFIG_PFAULT
extern void pfault_irq_init(void);
extern int pfault_init(void);
extern void pfault_fini(void);
#else /* CONFIG_PFAULT */
#define pfault_irq_init() do { } while (0)
#define pfault_init() ({-1;})
#define pfault_fini() do { } while (0)
#endif /* CONFIG_PFAULT */
extern void cmma_init(void);
extern int memcpy_real(void *, void *, size_t);
#define finish_arch_switch(prev) do { \
set_fs(current->thread.mm_segment); \
account_vtime(prev, current); \
} while (0)
#define nop() asm volatile("nop")
#define xchg(ptr,x) \
({ \
__typeof__(*(ptr)) __ret; \
__ret = (__typeof__(*(ptr))) \
__xchg((unsigned long)(x), (void *)(ptr),sizeof(*(ptr))); \
__ret; \
})
extern void __xchg_called_with_bad_pointer(void);
static inline unsigned long __xchg(unsigned long x, void * ptr, int size)
{
unsigned long addr, old;
int shift;
switch (size) {
case 1:
addr = (unsigned long) ptr;
shift = (3 ^ (addr & 3)) << 3;
addr ^= addr & 3;
asm volatile(
" l %0,%4\n"
"0: lr 0,%0\n"
" nr 0,%3\n"
" or 0,%2\n"
" cs %0,0,%4\n"
" jl 0b\n"
: "=&d" (old), "=Q" (*(int *) addr)
: "d" (x << shift), "d" (~(255 << shift)),
"Q" (*(int *) addr) : "memory", "cc", "0");
return old >> shift;
case 2:
addr = (unsigned long) ptr;
shift = (2 ^ (addr & 2)) << 3;
addr ^= addr & 2;
asm volatile(
" l %0,%4\n"
"0: lr 0,%0\n"
" nr 0,%3\n"
" or 0,%2\n"
" cs %0,0,%4\n"
" jl 0b\n"
: "=&d" (old), "=Q" (*(int *) addr)
: "d" (x << shift), "d" (~(65535 << shift)),
"Q" (*(int *) addr) : "memory", "cc", "0");
return old >> shift;
case 4:
asm volatile(
" l %0,%3\n"
"0: cs %0,%2,%3\n"
" jl 0b\n"
: "=&d" (old), "=Q" (*(int *) ptr)
: "d" (x), "Q" (*(int *) ptr)
: "memory", "cc");
return old;
#ifdef __s390x__
case 8:
asm volatile(
" lg %0,%3\n"
"0: csg %0,%2,%3\n"
" jl 0b\n"
: "=&d" (old), "=m" (*(long *) ptr)
: "d" (x), "Q" (*(long *) ptr)
: "memory", "cc");
return old;
#endif /* __s390x__ */
}
__xchg_called_with_bad_pointer();
return x;
}
/*
* Atomic compare and exchange. Compare OLD with MEM, if identical,
* store NEW in MEM. Return the initial value in MEM. Success is
* indicated by comparing RETURN with OLD.
*/
#define __HAVE_ARCH_CMPXCHG 1
#define cmpxchg(ptr, o, n) \
((__typeof__(*(ptr)))__cmpxchg((ptr), (unsigned long)(o), \
(unsigned long)(n), sizeof(*(ptr))))
extern void __cmpxchg_called_with_bad_pointer(void);
static inline unsigned long
__cmpxchg(volatile void *ptr, unsigned long old, unsigned long new, int size)
{
unsigned long addr, prev, tmp;
int shift;
switch (size) {
case 1:
addr = (unsigned long) ptr;
shift = (3 ^ (addr & 3)) << 3;
addr ^= addr & 3;
asm volatile(
" l %0,%2\n"
"0: nr %0,%5\n"
" lr %1,%0\n"
" or %0,%3\n"
" or %1,%4\n"
" cs %0,%1,%2\n"
" jnl 1f\n"
" xr %1,%0\n"
" nr %1,%5\n"
" jnz 0b\n"
"1:"
: "=&d" (prev), "=&d" (tmp), "=Q" (*(int *) ptr)
: "d" (old << shift), "d" (new << shift),
"d" (~(255 << shift)), "Q" (*(int *) ptr)
: "memory", "cc");
return prev >> shift;
case 2:
addr = (unsigned long) ptr;
shift = (2 ^ (addr & 2)) << 3;
addr ^= addr & 2;
asm volatile(
" l %0,%2\n"
"0: nr %0,%5\n"
" lr %1,%0\n"
" or %0,%3\n"
" or %1,%4\n"
" cs %0,%1,%2\n"
" jnl 1f\n"
" xr %1,%0\n"
" nr %1,%5\n"
" jnz 0b\n"
"1:"
: "=&d" (prev), "=&d" (tmp), "=Q" (*(int *) ptr)
: "d" (old << shift), "d" (new << shift),
"d" (~(65535 << shift)), "Q" (*(int *) ptr)
: "memory", "cc");
return prev >> shift;
case 4:
asm volatile(
" cs %0,%3,%1\n"
: "=&d" (prev), "=Q" (*(int *) ptr)
: "0" (old), "d" (new), "Q" (*(int *) ptr)
: "memory", "cc");
return prev;
#ifdef __s390x__
case 8:
asm volatile(
" csg %0,%3,%1\n"
: "=&d" (prev), "=Q" (*(long *) ptr)
: "0" (old), "d" (new), "Q" (*(long *) ptr)
: "memory", "cc");
return prev;
#endif /* __s390x__ */
}
__cmpxchg_called_with_bad_pointer();
return old;
}
/*
* Force strict CPU ordering.
* And yes, this is required on UP too when we're talking
* to devices.
*
* This is very similar to the ppc eieio/sync instruction in that is
* does a checkpoint syncronisation & makes sure that
* all memory ops have completed wrt other CPU's ( see 7-15 POP DJB ).
*/
#define eieio() asm volatile("bcr 15,0" : : : "memory")
#define SYNC_OTHER_CORES(x) eieio()
#define mb() eieio()
#define rmb() eieio()
#define wmb() eieio()
#define read_barrier_depends() do { } while(0)
#define smp_mb() mb()
#define smp_rmb() rmb()
#define smp_wmb() wmb()
#define smp_read_barrier_depends() read_barrier_depends()
#define smp_mb__before_clear_bit() smp_mb()
#define smp_mb__after_clear_bit() smp_mb()
#define set_mb(var, value) do { var = value; mb(); } while (0)
#ifdef __s390x__
#define __ctl_load(array, low, high) ({ \
typedef struct { char _[sizeof(array)]; } addrtype; \
asm volatile( \
" lctlg %1,%2,%0\n" \
: : "Q" (*(addrtype *)(&array)), \
"i" (low), "i" (high)); \
})
#define __ctl_store(array, low, high) ({ \
typedef struct { char _[sizeof(array)]; } addrtype; \
asm volatile( \
" stctg %1,%2,%0\n" \
: "=Q" (*(addrtype *)(&array)) \
: "i" (low), "i" (high)); \
})
#else /* __s390x__ */
#define __ctl_load(array, low, high) ({ \
typedef struct { char _[sizeof(array)]; } addrtype; \
asm volatile( \
" lctl %1,%2,%0\n" \
: : "Q" (*(addrtype *)(&array)), \
"i" (low), "i" (high)); \
})
#define __ctl_store(array, low, high) ({ \
typedef struct { char _[sizeof(array)]; } addrtype; \
asm volatile( \
" stctl %1,%2,%0\n" \
: "=Q" (*(addrtype *)(&array)) \
: "i" (low), "i" (high)); \
})
#endif /* __s390x__ */
#define __ctl_set_bit(cr, bit) ({ \
unsigned long __dummy; \
__ctl_store(__dummy, cr, cr); \
__dummy |= 1UL << (bit); \
__ctl_load(__dummy, cr, cr); \
})
#define __ctl_clear_bit(cr, bit) ({ \
unsigned long __dummy; \
__ctl_store(__dummy, cr, cr); \
__dummy &= ~(1UL << (bit)); \
__ctl_load(__dummy, cr, cr); \
})
#include <linux/irqflags.h>
#include <asm-generic/cmpxchg-local.h>
static inline unsigned long __cmpxchg_local(volatile void *ptr,
unsigned long old,
unsigned long new, int size)
{
switch (size) {
case 1:
case 2:
case 4:
#ifdef __s390x__
case 8:
#endif
return __cmpxchg(ptr, old, new, size);
default:
return __cmpxchg_local_generic(ptr, old, new, size);
}
return old;
}
/*
* cmpxchg_local and cmpxchg64_local are atomic wrt current CPU. Always make
* them available.
*/
#define cmpxchg_local(ptr, o, n) \
((__typeof__(*(ptr)))__cmpxchg_local((ptr), (unsigned long)(o), \
(unsigned long)(n), sizeof(*(ptr))))
#ifdef __s390x__
#define cmpxchg64_local(ptr, o, n) \
({ \
BUILD_BUG_ON(sizeof(*(ptr)) != 8); \
cmpxchg_local((ptr), (o), (n)); \
})
#else
#define cmpxchg64_local(ptr, o, n) __cmpxchg64_local_generic((ptr), (o), (n))
#endif
/*
* Use to set psw mask except for the first byte which
* won't be changed by this function.
*/
static inline void
__set_psw_mask(unsigned long mask)
{
__load_psw_mask(mask | (arch_local_save_flags() & ~(-1UL >> 8)));
}
#define local_mcck_enable() __set_psw_mask(psw_kernel_bits)
#define local_mcck_disable() __set_psw_mask(psw_kernel_bits & ~PSW_MASK_MCHECK)
#ifdef CONFIG_SMP
extern void smp_ctl_set_bit(int cr, int bit);
extern void smp_ctl_clear_bit(int cr, int bit);
#define ctl_set_bit(cr, bit) smp_ctl_set_bit(cr, bit)
#define ctl_clear_bit(cr, bit) smp_ctl_clear_bit(cr, bit)
#else
#define ctl_set_bit(cr, bit) __ctl_set_bit(cr, bit)
#define ctl_clear_bit(cr, bit) __ctl_clear_bit(cr, bit)
#endif /* CONFIG_SMP */
static inline unsigned int stfl(void)
{
asm volatile(
" .insn s,0xb2b10000,0(0)\n" /* stfl */
"0:\n"
EX_TABLE(0b,0b));
return S390_lowcore.stfl_fac_list;
}
static inline int __stfle(unsigned long long *list, int doublewords)
{
typedef struct { unsigned long long _[doublewords]; } addrtype;
register unsigned long __nr asm("0") = doublewords - 1;
asm volatile(".insn s,0xb2b00000,%0" /* stfle */
: "=m" (*(addrtype *) list), "+d" (__nr) : : "cc");
return __nr + 1;
}
static inline int stfle(unsigned long long *list, int doublewords)
{
if (!(stfl() & (1UL << 24)))
return -EOPNOTSUPP;
return __stfle(list, doublewords);
}
static inline unsigned short stap(void)
{
unsigned short cpu_address;
asm volatile("stap %0" : "=m" (cpu_address));
return cpu_address;
}
extern void (*_machine_restart)(char *command);
extern void (*_machine_halt)(void);
extern void (*_machine_power_off)(void);
#define arch_align_stack(x) (x)
static inline int tprot(unsigned long addr)
{
int rc = -EFAULT;
asm volatile(
" tprot 0(%1),0\n"
"0: ipm %0\n"
" srl %0,28\n"
"1:\n"
EX_TABLE(0b,1b)
: "+d" (rc) : "a" (addr) : "cc");
return rc;
}
#endif /* __KERNEL__ */
#endif