From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Tue, 21 May 2024 22:29:01 +0000 (-0700)
Subject: Merge tag 'bitmap-for-6.10v2' of https://github.com/norov/linux
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=4865a27c66fda6a32511ec5492f4bbec437f512d;p=linux.git

Merge tag 'bitmap-for-6.10v2' of https://github.com/norov/linux

Pull bitmap updates from Yury Norov:

 - topology_span_sane() optimization from Kyle Meyer

 - fns() rework from Kuan-Wei Chiu (used in cpumask_local_spread() and
   other places)

 - headers cleanup from Andy

 - add a MAINTAINERS record for bitops API

* tag 'bitmap-for-6.10v2' of https://github.com/norov/linux:
  usercopy: Don't use "proxy" headers
  bitops: Move aligned_byte_mask() to wordpart.h
  MAINTAINERS: add BITOPS API record
  bitmap: relax find_nth_bit() limitation on return value
  lib: make test_bitops compilable into the kernel image
  bitops: Optimize fns() for improved performance
  lib/test_bitops: Add benchmark test for fns()
  Compiler Attributes: Add __always_used macro
  sched/topology: Optimize topology_span_sane()
  cpumask: Add for_each_cpu_from()
---

4865a27c66fda6a32511ec5492f4bbec437f512d
diff --cc include/linux/bitops.h
index 3112ae7d6524b,3313d2c04e6d9..46d4bdc634c0b
--- a/include/linux/bitops.h
+++ b/include/linux/bitops.h
@@@ -255,18 -245,12 +248,12 @@@ static inline unsigned int __ffs64(u64 
   * @word: The word to search
   * @n: Bit to find
   */
 -static inline unsigned long fns(unsigned long word, unsigned int n)
 +static inline unsigned int fns(unsigned long word, unsigned int n)
  {
- 	unsigned int bit;
- 
- 	while (word) {
- 		bit = __ffs(word);
- 		if (n-- == 0)
- 			return bit;
- 		__clear_bit(bit, &word);
- 	}
+ 	while (word && n--)
+ 		word &= word - 1;
  
- 	return BITS_PER_LONG;
+ 	return word ? __ffs(word) : BITS_PER_LONG;
  }
  
  /**