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author | Arnaldo Carvalho de Melo <acme@redhat.com> | 2014-12-15 19:50:12 -0300 |
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committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2014-12-17 11:14:48 -0300 |
commit | 23e1a358e81017759714cb413a0e930d4f892563 (patch) | |
tree | 6ad2a1c06e8b968c869e3f16a82cbbe8ce3ec502 /tools/lib/util | |
parent | 93c49b3e535659102aa1ca28b775b48e3594036c (diff) | |
download | op-kernel-dev-23e1a358e81017759714cb413a0e930d4f892563.zip op-kernel-dev-23e1a358e81017759714cb413a0e930d4f892563.tar.gz |
tools lib: Move asm-generic/bitops/find.h code to tools/include and tools/lib
To match the Linux kernel source code structure from where this code came from.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-fkbma1h04ki0zzdmp0dpgfyy@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/lib/util')
-rw-r--r-- | tools/lib/util/find_next_bit.c | 89 |
1 files changed, 89 insertions, 0 deletions
diff --git a/tools/lib/util/find_next_bit.c b/tools/lib/util/find_next_bit.c new file mode 100644 index 0000000..41b44f6 --- /dev/null +++ b/tools/lib/util/find_next_bit.c @@ -0,0 +1,89 @@ +/* find_next_bit.c: fallback find next bit implementation + * + * Copied from lib/find_next_bit.c to tools/lib/next_bit.c + * + * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * 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/bitops.h> +#include <asm/types.h> +#include <asm/byteorder.h> + +#define BITOP_WORD(nr) ((nr) / BITS_PER_LONG) + +#ifndef find_next_bit +/* + * Find the next set bit in a memory region. + */ +unsigned long find_next_bit(const unsigned long *addr, unsigned long size, + unsigned long offset) +{ + const unsigned long *p = addr + BITOP_WORD(offset); + unsigned long result = offset & ~(BITS_PER_LONG-1); + unsigned long tmp; + + if (offset >= size) + return size; + size -= result; + offset %= BITS_PER_LONG; + if (offset) { + tmp = *(p++); + tmp &= (~0UL << offset); + if (size < BITS_PER_LONG) + goto found_first; + if (tmp) + goto found_middle; + size -= BITS_PER_LONG; + result += BITS_PER_LONG; + } + while (size & ~(BITS_PER_LONG-1)) { + if ((tmp = *(p++))) + goto found_middle; + result += BITS_PER_LONG; + size -= BITS_PER_LONG; + } + if (!size) + return result; + tmp = *p; + +found_first: + tmp &= (~0UL >> (BITS_PER_LONG - size)); + if (tmp == 0UL) /* Are any bits set? */ + return result + size; /* Nope. */ +found_middle: + return result + __ffs(tmp); +} +#endif + +#ifndef find_first_bit +/* + * Find the first set bit in a memory region. + */ +unsigned long find_first_bit(const unsigned long *addr, unsigned long size) +{ + const unsigned long *p = addr; + unsigned long result = 0; + unsigned long tmp; + + while (size & ~(BITS_PER_LONG-1)) { + if ((tmp = *(p++))) + goto found; + result += BITS_PER_LONG; + size -= BITS_PER_LONG; + } + if (!size) + return result; + + tmp = (*p) & (~0UL >> (BITS_PER_LONG - size)); + if (tmp == 0UL) /* Are any bits set? */ + return result + size; /* Nope. */ +found: + return result + __ffs(tmp); +} +#endif |