diff options
author | Dawei Li <dawei.li@shingroup.cn> | 2024-04-16 11:54:48 +0300 |
---|---|---|
committer | Thomas Gleixner <tglx@linutronix.de> | 2024-04-24 22:23:49 +0300 |
commit | cdc66553c4130735f0a2db943a5259e54ff1597a (patch) | |
tree | ec3ebe0bd50ede88a8dc482b80aacb2412a25e4b /include/linux | |
parent | c7cad38d37486668a448215fc92bace9c8cf747a (diff) | |
download | linux-cdc66553c4130735f0a2db943a5259e54ff1597a.tar.xz |
cpumask: Introduce cpumask_first_and_and()
Introduce cpumask_first_and_and() to get intersection between 3 cpumasks,
free of any intermediate cpumask variable. Instead, cpumask_first_and_and()
works in-place with all inputs and produces desired output directly.
Signed-off-by: Dawei Li <dawei.li@shingroup.cn>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Yury Norov <yury.norov@gmail.com>
Link: https://lore.kernel.org/r/20240416085454.3547175-2-dawei.li@shingroup.cn
Diffstat (limited to 'include/linux')
-rw-r--r-- | include/linux/cpumask.h | 17 | ||||
-rw-r--r-- | include/linux/find.h | 27 |
2 files changed, 44 insertions, 0 deletions
diff --git a/include/linux/cpumask.h b/include/linux/cpumask.h index 1c29947db848..c46f9e9e1d66 100644 --- a/include/linux/cpumask.h +++ b/include/linux/cpumask.h @@ -188,6 +188,23 @@ unsigned int cpumask_first_and(const struct cpumask *srcp1, const struct cpumask } /** + * cpumask_first_and_and - return the first cpu from *srcp1 & *srcp2 & *srcp3 + * @srcp1: the first input + * @srcp2: the second input + * @srcp3: the third input + * + * Return: >= nr_cpu_ids if no cpus set in all. + */ +static inline +unsigned int cpumask_first_and_and(const struct cpumask *srcp1, + const struct cpumask *srcp2, + const struct cpumask *srcp3) +{ + return find_first_and_and_bit(cpumask_bits(srcp1), cpumask_bits(srcp2), + cpumask_bits(srcp3), small_cpumask_bits); +} + +/** * cpumask_last - get the last CPU in a cpumask * @srcp: - the cpumask pointer * diff --git a/include/linux/find.h b/include/linux/find.h index c69598e383c1..28ec5a03393a 100644 --- a/include/linux/find.h +++ b/include/linux/find.h @@ -29,6 +29,8 @@ unsigned long __find_nth_and_andnot_bit(const unsigned long *addr1, const unsign unsigned long n); extern unsigned long _find_first_and_bit(const unsigned long *addr1, const unsigned long *addr2, unsigned long size); +unsigned long _find_first_and_and_bit(const unsigned long *addr1, const unsigned long *addr2, + const unsigned long *addr3, unsigned long size); extern unsigned long _find_first_zero_bit(const unsigned long *addr, unsigned long size); extern unsigned long _find_last_bit(const unsigned long *addr, unsigned long size); @@ -345,6 +347,31 @@ unsigned long find_first_and_bit(const unsigned long *addr1, } #endif +/** + * find_first_and_and_bit - find the first set bit in 3 memory regions + * @addr1: The first address to base the search on + * @addr2: The second address to base the search on + * @addr3: The third address to base the search on + * @size: The bitmap size in bits + * + * Returns the bit number for the first set bit + * If no bits are set, returns @size. + */ +static inline +unsigned long find_first_and_and_bit(const unsigned long *addr1, + const unsigned long *addr2, + const unsigned long *addr3, + unsigned long size) +{ + if (small_const_nbits(size)) { + unsigned long val = *addr1 & *addr2 & *addr3 & GENMASK(size - 1, 0); + + return val ? __ffs(val) : size; + } + + return _find_first_and_and_bit(addr1, addr2, addr3, size); +} + #ifndef find_first_zero_bit /** * find_first_zero_bit - find the first cleared bit in a memory region |