Messages in this thread | | | Date | Thu, 16 Oct 2008 15:56:30 -0700 | From | Mike Travis <> | Subject | Re: [PATCH 2/4] seq_file: Add seq_cpumask_list(), seq_nodemask_list() |
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Andrew Morton wrote: > On Sun, 12 Oct 2008 17:29:25 +0800 > Lai Jiangshan <laijs@cn.fujitsu.com> wrote: > >> +static inline int seq_cpumask_list(struct seq_file *m, cpumask_t *mask) >> +{ >> + return seq_bitmap_list(m, mask->bits, NR_CPUS); >> +} > > Is it possible to avoid using NR_CPUS? In some situations it'd be much > more efficient to use the runtime-determined max possible cpu index. > > But I don't immediately recall how to get at that number. > num_possible_cpus() assumes that there are no holes in the CPU > identifier list. >
nr_cpu_ids represents the max index +1 of the possible cpus. (Usually the same as num_possible_cpus() except a.) it doesn't need to do the cpus_weight() op, and b.) *if* (a big if) the cpu indices are sparse, then they wouldn't be the same values.)
Thanks, Mike
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