bitops.h

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#ifndef _ASM_IA64_BITOPS_H
#define _ASM_IA64_BITOPS_H

/*
 * Copyright (C) 1998-2003 Hewlett-Packard Co
 *  David Mosberger-Tang <[email protected]>
 *
 * 02/06/02 find_next_bit() and find_first_bit() added from Erich Focht's ia64
 * O(1) scheduler patch
 */

#ifndef _LINUX_BITOPS_H
#error only <linux/bitops.h> can be included directly
#endif

#include <linux/compiler.h>
#include <linux/types.h>
#include <asm/intrinsics.h>

static __inline__ void
set_bit (int nr, volatile void *addr)
{
    __u32 bit, old, new;
    volatile __u32 *m;
    CMPXCHG_BUGCHECK_DECL

    m = (volatile __u32 *) addr + (nr >> 5);
    bit = 1 << (nr & 31);
    do {
        CMPXCHG_BUGCHECK(m);
        old = *m;
        new = old | bit;
    } while (cmpxchg_acq(m, old, new) != old);
}

static __inline__ void
__set_bit (int nr, volatile void *addr)
{
    *((__u32 *) addr + (nr >> 5)) |= (1 << (nr & 31));
}

/*
 * clear_bit() has "acquire" semantics.
 */
#define smp_mb__before_clear_bit()  smp_mb()
#define smp_mb__after_clear_bit()   do { /* skip */; } while (0)

static __inline__ void
clear_bit (int nr, volatile void *addr)
{
    __u32 mask, old, new;
    volatile __u32 *m;
    CMPXCHG_BUGCHECK_DECL

    m = (volatile __u32 *) addr + (nr >> 5);
    mask = ~(1 << (nr & 31));
    do {
        CMPXCHG_BUGCHECK(m);
        old = *m;
        new = old & mask;
    } while (cmpxchg_acq(m, old, new) != old);
}

static __inline__ void
clear_bit_unlock (int nr, volatile void *addr)
{
    __u32 mask, old, new;
    volatile __u32 *m;
    CMPXCHG_BUGCHECK_DECL

    m = (volatile __u32 *) addr + (nr >> 5);
    mask = ~(1 << (nr & 31));
    do {
        CMPXCHG_BUGCHECK(m);
        old = *m;
        new = old & mask;
    } while (cmpxchg_rel(m, old, new) != old);
}

static __inline__ void
__clear_bit_unlock(int nr, void *addr)
{
    __u32 * const m = (__u32 *) addr + (nr >> 5);
    __u32 const new = *m & ~(1 << (nr & 31));

    ia64_st4_rel_nta(m, new);
}

static __inline__ void
__clear_bit (int nr, volatile void *addr)
{
    *((__u32 *) addr + (nr >> 5)) &= ~(1 << (nr & 31));
}

static __inline__ void
change_bit (int nr, volatile void *addr)
{
    __u32 bit, old, new;
    volatile __u32 *m;
    CMPXCHG_BUGCHECK_DECL

    m = (volatile __u32 *) addr + (nr >> 5);
    bit = (1 << (nr & 31));
    do {
        CMPXCHG_BUGCHECK(m);
        old = *m;
        new = old ^ bit;
    } while (cmpxchg_acq(m, old, new) != old);
}

static __inline__ void
__change_bit (int nr, volatile void *addr)
{
    *((__u32 *) addr + (nr >> 5)) ^= (1 << (nr & 31));
}

static __inline__ int
test_and_set_bit (int nr, volatile void *addr)
{
    __u32 bit, old, new;
    volatile __u32 *m;
    CMPXCHG_BUGCHECK_DECL

    m = (volatile __u32 *) addr + (nr >> 5);
    bit = 1 << (nr & 31);
    do {
        CMPXCHG_BUGCHECK(m);
        old = *m;
        new = old | bit;
    } while (cmpxchg_acq(m, old, new) != old);
    return (old & bit) != 0;
}

#define test_and_set_bit_lock test_and_set_bit

static __inline__ int
__test_and_set_bit (int nr, volatile void *addr)
{
    __u32 *p = (__u32 *) addr + (nr >> 5);
    __u32 m = 1 << (nr & 31);
    int oldbitset = (*p & m) != 0;

    *p |= m;
    return oldbitset;
}

static __inline__ int
test_and_clear_bit (int nr, volatile void *addr)
{
    __u32 mask, old, new;
    volatile __u32 *m;
    CMPXCHG_BUGCHECK_DECL

    m = (volatile __u32 *) addr + (nr >> 5);
    mask = ~(1 << (nr & 31));
    do {
        CMPXCHG_BUGCHECK(m);
        old = *m;
        new = old & mask;
    } while (cmpxchg_acq(m, old, new) != old);
    return (old & ~mask) != 0;
}

static __inline__ int
__test_and_clear_bit(int nr, volatile void * addr)
{
    __u32 *p = (__u32 *) addr + (nr >> 5);
    __u32 m = 1 << (nr & 31);
    int oldbitset = (*p & m) != 0;

    *p &= ~m;
    return oldbitset;
}

static __inline__ int
test_and_change_bit (int nr, volatile void *addr)
{
    __u32 bit, old, new;
    volatile __u32 *m;
    CMPXCHG_BUGCHECK_DECL

    m = (volatile __u32 *) addr + (nr >> 5);
    bit = (1 << (nr & 31));
    do {
        CMPXCHG_BUGCHECK(m);
        old = *m;
        new = old ^ bit;
    } while (cmpxchg_acq(m, old, new) != old);
    return (old & bit) != 0;
}

static __inline__ int
__test_and_change_bit (int nr, void *addr)
{
    __u32 old, bit = (1 << (nr & 31));
    __u32 *m = (__u32 *) addr + (nr >> 5);

    old = *m;
    *m = old ^ bit;
    return (old & bit) != 0;
}

static __inline__ int
test_bit (int nr, const volatile void *addr)
{
    return 1 & (((const volatile __u32 *) addr)[nr >> 5] >> (nr & 31));
}

static inline unsigned long
ffz (unsigned long x)
{
    unsigned long result;

    result = ia64_popcnt(x & (~x - 1));
    return result;
}

static __inline__ unsigned long
__ffs (unsigned long x)
{
    unsigned long result;

    result = ia64_popcnt((x-1) & ~x);
    return result;
}

#ifdef __KERNEL__

/*
 * Return bit number of last (most-significant) bit set.  Undefined
 * for x==0.  Bits are numbered from 0..63 (e.g., ia64_fls(9) == 3).
 */
static inline unsigned long
ia64_fls (unsigned long x)
{
    long double d = x;
    long exp;

    exp = ia64_getf_exp(d);
    return exp - 0xffff;
}

/*
 * Find the last (most significant) bit set.  Returns 0 for x==0 and
 * bits are numbered from 1..32 (e.g., fls(9) == 4).
 */
static inline int
fls (int t)
{
    unsigned long x = t & 0xffffffffu;

    if (!x)
        return 0;
    x |= x >> 1;
    x |= x >> 2;
    x |= x >> 4;
    x |= x >> 8;
    x |= x >> 16;
    return ia64_popcnt(x);
}

/*
 * Find the last (most significant) bit set.  Undefined for x==0.
 * Bits are numbered from 0..63 (e.g., __fls(9) == 3).
 */
static inline unsigned long
__fls (unsigned long x)
{
    x |= x >> 1;
    x |= x >> 2;
    x |= x >> 4;
    x |= x >> 8;
    x |= x >> 16;
    x |= x >> 32;
    return ia64_popcnt(x) - 1;
}

#include <asm-generic/bitops/fls64.h>

/*
 * ffs: find first bit set. This is defined the same way as the libc and
 * compiler builtin ffs routines, therefore differs in spirit from the above
 * ffz (man ffs): it operates on "int" values only and the result value is the
 * bit number + 1.  ffs(0) is defined to return zero.
 */
#define ffs(x)  __builtin_ffs(x)

/*
 * hweightN: returns the hamming weight (i.e. the number
 * of bits set) of a N-bit word
 */
static __inline__ unsigned long __arch_hweight64(unsigned long x)
{
    unsigned long result;
    result = ia64_popcnt(x);
    return result;
}

#define __arch_hweight32(x) ((unsigned int) __arch_hweight64((x) & 0xfffffffful))
#define __arch_hweight16(x) ((unsigned int) __arch_hweight64((x) & 0xfffful))
#define __arch_hweight8(x)  ((unsigned int) __arch_hweight64((x) & 0xfful))

#include <asm-generic/bitops/const_hweight.h>

#endif /* __KERNEL__ */

#include <asm-generic/bitops/find.h>

#ifdef __KERNEL__

#include <asm-generic/bitops/le.h>

#include <asm-generic/bitops/ext2-atomic-setbit.h>

#include <asm-generic/bitops/sched.h>

#endif /* __KERNEL__ */

#endif /* _ASM_IA64_BITOPS_H */