linux/arch/tile/include/asm/bitops_64.h
Chris Metcalf 664c100bce arch/tile: fix gcc 4.6 warnings in <asm/bitops_64.h>
Fix some signedness and variable usage warnings in change_bit()
and test_and_change_bit().

Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2012-04-02 12:00:15 -04:00

102 lines
2.8 KiB
C

/*
* Copyright 2011 Tilera Corporation. All Rights Reserved.
*
* 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, version 2.
*
* This program 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, GOOD TITLE or
* NON INFRINGEMENT. See the GNU General Public License for
* more details.
*/
#ifndef _ASM_TILE_BITOPS_64_H
#define _ASM_TILE_BITOPS_64_H
#include <linux/compiler.h>
#include <linux/atomic.h>
/* See <asm/bitops.h> for API comments. */
static inline void set_bit(unsigned nr, volatile unsigned long *addr)
{
unsigned long mask = (1UL << (nr % BITS_PER_LONG));
__insn_fetchor((void *)(addr + nr / BITS_PER_LONG), mask);
}
static inline void clear_bit(unsigned nr, volatile unsigned long *addr)
{
unsigned long mask = (1UL << (nr % BITS_PER_LONG));
__insn_fetchand((void *)(addr + nr / BITS_PER_LONG), ~mask);
}
#define smp_mb__before_clear_bit() smp_mb()
#define smp_mb__after_clear_bit() smp_mb()
static inline void change_bit(unsigned nr, volatile unsigned long *addr)
{
unsigned long mask = (1UL << (nr % BITS_PER_LONG));
unsigned long guess, oldval;
addr += nr / BITS_PER_LONG;
oldval = *addr;
do {
guess = oldval;
oldval = atomic64_cmpxchg((atomic64_t *)addr,
guess, guess ^ mask);
} while (guess != oldval);
}
/*
* The test_and_xxx_bit() routines require a memory fence before we
* start the operation, and after the operation completes. We use
* smp_mb() before, and rely on the "!= 0" comparison, plus a compiler
* barrier(), to block until the atomic op is complete.
*/
static inline int test_and_set_bit(unsigned nr, volatile unsigned long *addr)
{
int val;
unsigned long mask = (1UL << (nr % BITS_PER_LONG));
smp_mb(); /* barrier for proper semantics */
val = (__insn_fetchor((void *)(addr + nr / BITS_PER_LONG), mask)
& mask) != 0;
barrier();
return val;
}
static inline int test_and_clear_bit(unsigned nr, volatile unsigned long *addr)
{
int val;
unsigned long mask = (1UL << (nr % BITS_PER_LONG));
smp_mb(); /* barrier for proper semantics */
val = (__insn_fetchand((void *)(addr + nr / BITS_PER_LONG), ~mask)
& mask) != 0;
barrier();
return val;
}
static inline int test_and_change_bit(unsigned nr,
volatile unsigned long *addr)
{
unsigned long mask = (1UL << (nr % BITS_PER_LONG));
unsigned long guess, oldval;
addr += nr / BITS_PER_LONG;
oldval = *addr;
do {
guess = oldval;
oldval = atomic64_cmpxchg((atomic64_t *)addr,
guess, guess ^ mask);
} while (guess != oldval);
return (oldval & mask) != 0;
}
#include <asm-generic/bitops/ext2-atomic-setbit.h>
#endif /* _ASM_TILE_BITOPS_64_H */