diff options
| author | Valentin Schneider <vschneid@redhat.com> | 2022-10-03 18:34:18 +0300 |
|---|---|---|
| committer | Yury Norov <yury.norov@gmail.com> | 2022-10-06 15:57:36 +0300 |
| commit | 5f75ff295c662c1c8fb9e1737e9dc3b9a1e7fb29 (patch) | |
| tree | 3d5bc8c5fe350f59a27426efb5b2de4c75f6fa31 | |
| parent | 90d482908eedd56f01a707325aa541cf9c40f936 (diff) | |
| download | linux-5f75ff295c662c1c8fb9e1737e9dc3b9a1e7fb29.tar.xz | |
cpumask: Introduce for_each_cpu_andnot()
for_each_cpu_and() is very convenient as it saves having to allocate a
temporary cpumask to store the result of cpumask_and(). The same issue
applies to cpumask_andnot() which doesn't actually need temporary storage
for iteration purposes.
Following what has been done for for_each_cpu_and(), introduce
for_each_cpu_andnot().
Signed-off-by: Valentin Schneider <vschneid@redhat.com>
| -rw-r--r-- | include/linux/cpumask.h | 18 | ||||
| -rw-r--r-- | include/linux/find.h | 5 |
2 files changed, 23 insertions, 0 deletions
diff --git a/include/linux/cpumask.h b/include/linux/cpumask.h index 286804bfe3b7..2f065ad97541 100644 --- a/include/linux/cpumask.h +++ b/include/linux/cpumask.h @@ -307,6 +307,24 @@ unsigned int __pure cpumask_next_wrap(int n, const struct cpumask *mask, int sta for_each_and_bit(cpu, cpumask_bits(mask1), cpumask_bits(mask2), nr_cpumask_bits) /** + * for_each_cpu_andnot - iterate over every cpu present in one mask, excluding + * those present in another. + * @cpu: the (optionally unsigned) integer iterator + * @mask1: the first cpumask pointer + * @mask2: the second cpumask pointer + * + * This saves a temporary CPU mask in many places. It is equivalent to: + * struct cpumask tmp; + * cpumask_andnot(&tmp, &mask1, &mask2); + * for_each_cpu(cpu, &tmp) + * ... + * + * After the loop, cpu is >= nr_cpu_ids. + */ +#define for_each_cpu_andnot(cpu, mask1, mask2) \ + for_each_andnot_bit(cpu, cpumask_bits(mask1), cpumask_bits(mask2), nr_cpumask_bits) + +/** * cpumask_any_but - return a "random" in a cpumask, but not this one. * @mask: the cpumask to search * @cpu: the cpu to ignore. diff --git a/include/linux/find.h b/include/linux/find.h index 2235af19e7e1..ccaf61a0f5fd 100644 --- a/include/linux/find.h +++ b/include/linux/find.h @@ -498,6 +498,11 @@ unsigned long find_next_bit_le(const void *addr, unsigned (bit) = find_next_and_bit((addr1), (addr2), (size), (bit)), (bit) < (size);\ (bit)++) +#define for_each_andnot_bit(bit, addr1, addr2, size) \ + for ((bit) = 0; \ + (bit) = find_next_andnot_bit((addr1), (addr2), (size), (bit)), (bit) < (size);\ + (bit)++) + /* same as for_each_set_bit() but use bit as value to start with */ #define for_each_set_bit_from(bit, addr, size) \ for (; (bit) = find_next_bit((addr), (size), (bit)), (bit) < (size); (bit)++) |