diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h index 7784b597e959..6013021a3b39 100644 --- a/include/linux/clocksource.h +++ b/include/linux/clocksource.h @@ -62,12 +62,18 @@ struct module; * @suspend: suspend function for the clocksource, if necessary * @resume: resume function for the clocksource, if necessary * @owner: module reference, must be set by clocksource in modules + * + * Note: This struct is not used in hotpathes of the timekeeping code + * because the timekeeper caches the hot path fields in its own data + * structure, so no line cache alignment is required, + * + * The pointer to the clocksource itself is handed to the read + * callback. If you need extra information there you can wrap struct + * clocksource into your own struct. Depending on the amount of + * information you need you should consider to cache line align that + * structure. */ struct clocksource { - /* - * Hotpath data, fits in a single cache line when the - * clocksource itself is cacheline aligned. - */ cycle_t (*read)(struct clocksource *cs); cycle_t mask; u32 mult; @@ -95,7 +101,7 @@ struct clocksource { cycle_t wd_last; #endif struct module *owner; -} ____cacheline_aligned; +}; /* * Clock source flags bits::