Thomas/Peter: On 06/17/2011 08:13 AM, David Ahern wrote: > > > On 06/17/2011 07:23 AM, Frederic Weisbecker wrote: >> On Tue, Jun 07, 2011 at 05:55:03PM -0600, David Ahern wrote: >>> Trace points in timekeeping.c where xtime is modified by a user >>> or ntp. >>> >>> Signed-off-by: David Ahern <[email protected]> >>> --- >>> include/trace/events/timekeeping.h | 43 >>> ++++++++++++++++++++++++++++++++++++ >>> kernel/time/timekeeping.c | 8 ++++++ >>> 2 files changed, 51 insertions(+), 0 deletions(-) >>> create mode 100644 include/trace/events/timekeeping.h >>> >>> diff --git a/include/trace/events/timekeeping.h >>> b/include/trace/events/timekeeping.h >>> new file mode 100644 >>> index 0000000..3d5d083 >>> --- /dev/null >>> +++ b/include/trace/events/timekeeping.h >>> @@ -0,0 +1,43 @@ >>> +#undef TRACE_SYSTEM >>> +#define TRACE_SYSTEM timekeeping >>> + >>> +#if !defined(_TRACE_TIMEKEEP_H) || defined(TRACE_HEADER_MULTI_READ) >>> +#define _TRACE_TIMEKEEP_H >>> + >>> +#include <linux/tracepoint.h> >>> +#include <linux/time.h> >>> + >>> +DECLARE_EVENT_CLASS(tod_template, >>> + >>> + TP_PROTO(const struct timespec *tv), >>> + >>> + TP_ARGS(tv), >>> + >>> + TP_STRUCT__entry( >>> + __field( __kernel_time_t, tv_sec) >>> + __field( long, tv_nsec) >>> + ), >>> + >>> + TP_fast_assign( >>> + __entry->tv_sec = tv->tv_sec; >>> + __entry->tv_nsec = tv->tv_nsec; >>> + ), >>> + >>> + TP_printk("tv_sec=%ld tv_nsec=%ld", __entry->tv_sec, __entry->tv_nsec) >>> +); >>> + >>> +DEFINE_EVENT(tod_template, settimeofday, >>> + TP_PROTO(const struct timespec *tv), >>> + TP_ARGS(tv)); >>> + >>> +DEFINE_EVENT(tod_template, timekeeping_inject_offset, >>> + TP_PROTO(const struct timespec *tv), >>> + TP_ARGS(tv)); >>> + >>> +DEFINE_EVENT(tod_template, timekeeping_inject_sleeptime, >>> + TP_PROTO(const struct timespec *tv), >>> + TP_ARGS(tv)); >> >> Does the fact it's any of the three way of updating xtime make any >> difference from the user point of view? > > This use case only cares that xtime is updated. > >> >> If not can we rather factorize that in a single settimeofday tracepoint? >> Or update_time_of_day if we don't want to confuse the user with the >> syscall. > > Peter and Thomas expressed interest in timekeeping tracepoints. How the > update happens might be wanted. If desired I can consolidate xtime = *tv > into a single update function and put the trace point there.
Any comments on the proposed trace points in the timekeeping code? I am working on a new spin of the patches and would like to know if there are changes needed here too. Thanks, David -- To unsubscribe from this list: send the line "unsubscribe linux-perf-users" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
