From: Vineeth Pillai <virem...@linux.microsoft.com> Hotplug fixes to core-scheduling require a new cpumask iterator which iterates through all online cpus in both the given cpumasks. This patch introduces it.
Signed-off-by: Vineeth Pillai <virem...@linux.microsoft.com> Signed-off-by: Joel Fernandes (Google) <j...@joelfernandes.org> --- include/linux/cpumask.h | 42 ++++++++++++++++++++++++++++++++ lib/cpumask.c | 53 +++++++++++++++++++++++++++++++++++++++++ 2 files changed, 95 insertions(+) diff --git a/include/linux/cpumask.h b/include/linux/cpumask.h index f0d895d6ac39..03e8c57c6ca6 100644 --- a/include/linux/cpumask.h +++ b/include/linux/cpumask.h @@ -207,6 +207,10 @@ static inline int cpumask_any_and_distribute(const struct cpumask *src1p, for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask, (void)(start)) #define for_each_cpu_and(cpu, mask1, mask2) \ for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask1, (void)mask2) +#define for_each_cpu_or(cpu, mask1, mask2) \ + for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask1, (void)mask2) +#define for_each_cpu_wrap_or(cpu, mask1, mask2, start) \ + for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask1, (void)mask2, (void)(start)) #else /** * cpumask_first - get the first cpu in a cpumask @@ -248,6 +252,7 @@ static inline unsigned int cpumask_next_zero(int n, const struct cpumask *srcp) } int cpumask_next_and(int n, const struct cpumask *, const struct cpumask *); +int cpumask_next_or(int n, const struct cpumask *, const struct cpumask *); int cpumask_any_but(const struct cpumask *mask, unsigned int cpu); unsigned int cpumask_local_spread(unsigned int i, int node); int cpumask_any_and_distribute(const struct cpumask *src1p, @@ -278,6 +283,8 @@ int cpumask_any_and_distribute(const struct cpumask *src1p, (cpu) < nr_cpu_ids;) extern int cpumask_next_wrap(int n, const struct cpumask *mask, int start, bool wrap); +extern int cpumask_next_wrap_or(int n, const struct cpumask *mask1, + const struct cpumask *mask2, int start, bool wrap); /** * for_each_cpu_wrap - iterate over every cpu in a mask, starting at a specified location @@ -294,6 +301,22 @@ extern int cpumask_next_wrap(int n, const struct cpumask *mask, int start, bool (cpu) < nr_cpumask_bits; \ (cpu) = cpumask_next_wrap((cpu), (mask), (start), true)) +/** + * for_each_cpu_wrap_or - iterate over every cpu in both masks, starting at a specified location + * @cpu: the (optionally unsigned) integer iterator + * @mask1: the first cpumask pointer + * @mask2: the second cpumask pointer + * @start: the start location + * + * The implementation does not assume any bit both masks are set (including @start). + * + * After the loop, cpu is >= nr_cpu_ids. + */ +#define for_each_cpu_wrap_or(cpu, mask1, mask2, start) \ + for ((cpu) = cpumask_next_wrap_or((start)-1, (mask1), (mask2), (start), false); \ + (cpu) < nr_cpumask_bits; \ + (cpu) = cpumask_next_wrap_or((cpu), (mask1), (mask2), (start), true)) + /** * for_each_cpu_and - iterate over every cpu in both masks * @cpu: the (optionally unsigned) integer iterator @@ -312,6 +335,25 @@ extern int cpumask_next_wrap(int n, const struct cpumask *mask, int start, bool for ((cpu) = -1; \ (cpu) = cpumask_next_and((cpu), (mask1), (mask2)), \ (cpu) < nr_cpu_ids;) + +/** + * for_each_cpu_or - iterate over every cpu in both masks + * @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_and(&tmp, &mask1, &mask2); + * for_each_cpu(cpu, &tmp) + * ... + * + * After the loop, cpu is >= nr_cpu_ids. + */ +#define for_each_cpu_or(cpu, mask1, mask2) \ + for ((cpu) = -1; \ + (cpu) = cpumask_next_or((cpu), (mask1), (mask2)), \ + (cpu) < nr_cpu_ids;) #endif /* SMP */ #define CPU_BITS_NONE \ diff --git a/lib/cpumask.c b/lib/cpumask.c index fb22fb266f93..0a5cdbd4eb6a 100644 --- a/lib/cpumask.c +++ b/lib/cpumask.c @@ -42,6 +42,25 @@ int cpumask_next_and(int n, const struct cpumask *src1p, } EXPORT_SYMBOL(cpumask_next_and); +/** + * cpumask_next_or - 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 + * @src2p: the second cpumask pointer + * + * Returns >= nr_cpu_ids if no further cpus set in both. + */ +int cpumask_next_or(int n, const struct cpumask *src1p, + const struct cpumask *src2p) +{ + /* -1 is a legal arg here. */ + if (n != -1) + cpumask_check(n); + return find_next_or_bit(cpumask_bits(src1p), cpumask_bits(src2p), + nr_cpumask_bits, n + 1); +} +EXPORT_SYMBOL(cpumask_next_or); + /** * cpumask_any_but - return a "random" in a cpumask, but not this one. * @mask: the cpumask to search @@ -94,6 +113,40 @@ int cpumask_next_wrap(int n, const struct cpumask *mask, int start, bool wrap) } EXPORT_SYMBOL(cpumask_next_wrap); +/** + * cpumask_next_wrap_or - helper to implement for_each_cpu_wrap_or + * @n: the cpu prior to the place to search + * @mask1: first cpumask pointer + * @mask2: second 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_or(int n, const struct cpumask *mask1, const struct cpumask *mask2, + int start, bool wrap) +{ + int next; + +again: + next = cpumask_next_or(n, mask1, mask2); + + 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_or); + /* These are not inline because of header tangles. */ #ifdef CONFIG_CPUMASK_OFFSTACK /** -- 2.28.0.220.ged08abb693-goog