Commit 4865a27c authored by Linus Torvalds's avatar Linus Torvalds
Browse files

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()
parents b6394d6f 5671dca2

MAINTAINERS

+14 −0
Original line number Diff line number Diff line
@@ -3725,6 +3725,20 @@ F: tools/include/vdso/bits.h 
F:	tools/lib/bitmap.c

F:	tools/lib/find_bit.c









BITOPS API









M:	Yury Norov <yury.norov@gmail.com>









R:	Rasmus Villemoes <linux@rasmusvillemoes.dk>









S:	Maintained









F:	arch/*/include/asm/bitops.h









F:	arch/*/include/asm/bitops_32.h









F:	arch/*/include/asm/bitops_64.h









F:	arch/*/lib/bitops.c









F:	include/asm-generic/bitops









F:	include/asm-generic/bitops.h









F:	include/linux/bitops.h









F:	lib/test_bitops.c









F:	tools/*/bitops*

















BLINKM RGB LED DRIVER









M:	Jan-Simon Moeller <jansimon.moeller@gmx.de>









S:	Maintained
































include/linux/bitops.h



+3
−16






























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@@ -8,13 +8,6 @@

















#include <uapi/linux/kernel.h>



















/* Set bits in the first 'n' bytes when loaded from memory */









#ifdef __LITTLE_ENDIAN









#  define aligned_byte_mask(n) ((1UL << 8*(n))-1)









#else









#  define aligned_byte_mask(n) (~0xffUL << (BITS_PER_LONG - 8 - 8*(n)))









#endif



















#define BITS_PER_TYPE(type)	(sizeof(type) * BITS_PER_BYTE)









#define BITS_TO_LONGS(nr)	__KERNEL_DIV_ROUND_UP(nr, BITS_PER_TYPE(long))









#define BITS_TO_U64(nr)		__KERNEL_DIV_ROUND_UP(nr, BITS_PER_TYPE(u64))








@@ -257,16 +250,10 @@ static inline unsigned int __ffs64(u64 word)







 */









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;









}



















/**
































include/linux/compiler_attributes.h



+13
−0






























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@@ -361,6 +361,19 @@







 */









#define __used                          __attribute__((__used__))



















/*









 * The __used attribute guarantees that the attributed variable will be









 * always emitted by a compiler. It doesn't prevent the compiler from









 * throwing 'unused' warnings when it can't detect how the variable is









 * actually used. It's a compiler implementation details either emit









 * the warning in that case or not.









 *









 * The combination of both 'used' and 'unused' attributes ensures that









 * the variable would be emitted, and will not trigger 'unused' warnings.









 * The attribute is applicable for functions, static and global variables.









 */









#define __always_used			__used __maybe_unused



















/*









 *   gcc: https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html#index-warn_005funused_005fresult-function-attribute









 * clang: https://clang.llvm.org/docs/AttributeReference.html#nodiscard-warn-unused-result
































include/linux/cpumask.h



+10
−0






























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@@ -385,6 +385,16 @@ unsigned int __pure cpumask_next_wrap(int n, const struct cpumask *mask, int sta







#define for_each_cpu_or(cpu, mask1, mask2)				\









	for_each_or_bit(cpu, cpumask_bits(mask1), cpumask_bits(mask2), small_cpumask_bits)



















/**









 * for_each_cpu_from - iterate over CPUs present in @mask, from @cpu to the end of @mask.









 * @cpu: the (optionally unsigned) integer iterator









 * @mask: the cpumask pointer









 *









 * After the loop, cpu is >= nr_cpu_ids.









 */









#define for_each_cpu_from(cpu, mask)				\









	for_each_set_bit_from(cpu, cpumask_bits(mask), small_cpumask_bits)



















/**









 * cpumask_any_but - return a "random" in a cpumask, but not this one.









 * @mask: the cpumask to search
































include/linux/find.h



+1
−1






























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@@ -222,7 +222,7 @@ unsigned long find_first_bit(const unsigned long *addr, unsigned long size)







 *	 idx = find_first_bit(addr, size);









 *









 * Returns the bit number of the N'th set bit.









 * If no such, returns @size.









 * If no such, returns >= @size.









 */









static inline









unsigned long find_nth_bit(const unsigned long *addr, unsigned long size, unsigned long n)