diff options
Diffstat (limited to 'lib/cpumask.c')
| -rw-r--r-- | lib/cpumask.c | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/lib/cpumask.c b/lib/cpumask.c index 81dedaab36cc..8b1a1bd77539 100644 --- a/lib/cpumask.c +++ b/lib/cpumask.c @@ -6,6 +6,22 @@ #include <linux/bootmem.h> /** + * cpumask_next - get the next cpu in a cpumask + * @n: the cpu prior to the place to search (ie. return will be > @n) + * @srcp: the cpumask pointer + * + * Returns >= nr_cpu_ids if no further cpus set. + */ +unsigned int cpumask_next(int n, const struct cpumask *srcp) +{ + /* -1 is a legal arg here. */ + if (n != -1) + cpumask_check(n); + return find_next_bit(cpumask_bits(srcp), nr_cpumask_bits, n + 1); +} +EXPORT_SYMBOL(cpumask_next); + +/** * cpumask_next_and - get the next cpu in *src1p & *src2p * @n: the cpu prior to the place to search (ie. return will be > @n) * @src1p: the first cpumask pointer @@ -43,6 +59,38 @@ int cpumask_any_but(const struct cpumask *mask, unsigned int cpu) } EXPORT_SYMBOL(cpumask_any_but); +/** + * cpumask_next_wrap - helper to implement for_each_cpu_wrap + * @n: the cpu prior to the place to search + * @mask: the cpumask pointer + * @start: the start point of the iteration + * @wrap: assume @n crossing @start terminates the iteration + * + * Returns >= nr_cpu_ids on completion + * + * Note: the @wrap argument is required for the start condition when + * we cannot assume @start is set in @mask. + */ +int cpumask_next_wrap(int n, const struct cpumask *mask, int start, bool wrap) +{ + int next; + +again: + next = cpumask_next(n, mask); + + if (wrap && n < start && next >= start) { + return nr_cpumask_bits; + + } else if (next >= nr_cpumask_bits) { + wrap = true; + n = -1; + goto again; + } + + return next; +} +EXPORT_SYMBOL(cpumask_next_wrap); + /* These are not inline because of header tangles. */ #ifdef CONFIG_CPUMASK_OFFSTACK /** |