From: Nathan Zimmer Date: Wed, 20 Feb 2013 02:13:46 +0000 (+1100) Subject: timer_list-convert-timer-list-to-be-a-proper-seq_file-v2 X-Git-Tag: next-20130220~1^2~633 X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=4250cbcc4a5fa9284482c8c1de4eb9af4533f172;p=karo-tx-linux.git timer_list-convert-timer-list-to-be-a-proper-seq_file-v2 v2: Added comments on the iteration. Signed-off-by: Nathan Zimmer Cc: John Stultz Cc: Thomas Gleixner Cc: Dave Jones Signed-off-by: Andrew Morton --- diff --git a/kernel/time/timer_list.c b/kernel/time/timer_list.c index c438d759228d..1098ee4d23c8 100644 --- a/kernel/time/timer_list.c +++ b/kernel/time/timer_list.c @@ -274,6 +274,19 @@ static int timer_list_show(struct seq_file *m, void *v) return 0; } +/* + * This itererator really needs some explination since it is offset and has + * two passes one of which is controlled by a config option. + * In a hotplugged system some cpus, including cpu 0, may be missing so we have + * to use cpumask_* to iterate over the cpus. + * For the first pass: + * It returns 1 for the header position. + * For cpu 0 it returns 2 and the final possible cpu would be nr_cpu_ids + 1. + * On the second pass: + * It returnes nr_cpu_ids + 1 for the second header position. + * For cpu 0 it returns nr_cpu_ids + 2 + * The final possible cpu would be nr_cpu_ids + nr_cpu_ids + 2. + */ static void *timer_list_start(struct seq_file *file, loff_t *offset) { unsigned long n = *offset;