lby/lk
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

generic: add ops/defines to work with multi-word bitmaps.

Browse Source
This commit is contained in:
Dima Zavin
2009-01-20 19:25:47 -08:00
committed by Brian Swetland
parent d153278b80
commit afa6839a16
1 changed files with 25 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

25
include/bits.h
View File

@@ -23,6 +23,8 @@
#ifndef __BITS_H
#define __BITS_H
#include <arch/ops.h>
#define clz(x) __builtin_clz(x)
#define BIT(x, bit) ((x) & (1 << (bit)))
@@ -31,4 +33,27 @@
#define BITS_SHIFT(x, high, low) (((x) >> (low)) & ((1<<((high)-(low)+1))-1))
#define BIT_SET(x, bit) (((x) & (1 << (bit))) ? 1 : 0)
#define BITMAP_BITS_PER_WORD (sizeof(unsigned long) * 8)
#define BITMAP_NUM_WORDS(x) (((x) / BITMAP_BITS_PER_WORD) + 1)
#define BITMAP_WORD(x) ((x) / BITMAP_BITS_PER_WORD)
#define BITMAP_BIT_IN_WORD(x) ((x) & (BITMAP_BITS_PER_WORD - 1))
static inline int bitmap_set(unsigned long *bitmap, int bit)
{
unsigned long mask = 1 << BITMAP_BIT_IN_WORD(bit);
return atomic_or((int*)&bitmap[BITMAP_WORD(bit)], mask) & mask ? 1 : 0;
}
static inline int bitmap_clear(unsigned long *bitmap, int bit)
{
unsigned long mask = 1 << BITMAP_BIT_IN_WORD(bit);
return atomic_and((int*)&bitmap[BITMAP_WORD(bit)], ~mask) & mask ? 1:0;
}
static inline int bitmap_test(unsigned long *bitmap, int bit)
{
return BIT_SET(bitmap[BITMAP_WORD(bit)], BITMAP_BIT_IN_WORD(bit));
}
#endif