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authorArnaldo Carvalho de Melo <acme@redhat.com>2016-01-08 10:46:52 -0300
committerArnaldo Carvalho de Melo <acme@redhat.com>2016-01-08 12:35:35 -0300
commit552eb975b83756e3d95aeb5edaeb5c3c032b0021 (patch)
tree4fb711b60f9525fe4fa53a6681eaa39cd517deff /tools/lib/find_bit.c
parenta831e67913e356be63d5bb0509fc1af3c4e6ceb4 (diff)
downloadlinux-552eb975b83756e3d95aeb5edaeb5c3c032b0021.tar.bz2
tools lib: Move find_next_bit.c to tools/lib/
The commit that introduced it should've moved it to the same place, plus the 'tools/' prefix, but instead moved it to a bogus tools/lib/util/ directory, being the only file there. Move it to tools/lib/find_bit.c, picking the name for the file where these routines live since: 8f6f19dd5143 ("lib: move find_last_bit to lib/find_next_bit.c") Next step is to make tools/lib/find_bit.c to differ from lib/find_bit.c just in removing what is not used by tools/. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Borislav Petkov <bp@suse.de> Cc: David Ahern <dsahern@gmail.com> Cc: George Spelvin <linux@horizon.com Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Wang Nan <wangnan0@huawei.com> Cc: Yury Norov <yury.norov@gmail.com> Link: http://lkml.kernel.org/n/tip-p391cex5mqvahp4pwrton87n@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/lib/find_bit.c')
-rw-r--r--tools/lib/find_bit.c89
1 files changed, 89 insertions, 0 deletions
diff --git a/tools/lib/find_bit.c b/tools/lib/find_bit.c
new file mode 100644
index 000000000000..732d8c38d2c3
--- /dev/null
+++ b/tools/lib/find_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/find_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