| Message ID | 20170718172525.114514-1-salyzyn@android.com (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
On Tue, 2017-07-18 at 10:25 -0700, Mark Salyzyn wrote: > Go directly to the rtc for persistent wall clock time and print. > Useful if REALTIME is required to be logged in a low level power > management function or when clock activities are suspended. An > aid to permit user space alignment of kernel activities. [] > diff --git a/include/linux/rtc.h b/include/linux/rtc.h [] > @@ -22,6 +22,11 @@ extern int rtc_year_days(unsigned int day, unsigned int month, unsigned int year > extern int rtc_valid_tm(struct rtc_time *tm); > extern time64_t rtc_tm_to_time64(struct rtc_time *tm); > extern void rtc_time64_to_tm(time64_t time, struct rtc_time *tm); > +#ifdef CONFIG_RTC_SHOW_TIME > +extern void rtc_show_time(const char *prefix_msg); > +#else > +#define rtc_show_time(prefix_msg) It's generally better to use a static inline to avoid misuses in newly added code in the !CONFIG_RTC_SHOW_TIME compile path when CONFIG_RTC_SHOW_TIME may not be compiled. static inline void rtc_show_time(const char *prefix_msg) { }
On Tue, Jul 18, 2017 at 8:25 PM, Mark Salyzyn <salyzyn@android.com> wrote: > Go directly to the rtc for persistent wall clock time and print. > Useful if REALTIME is required to be logged in a low level power > management function or when clock activities are suspended. An > aid to permit user space alignment of kernel activities. > > Feature activated by CONFIG_RTC_SHOW_TIME. What's wrong with procfs device nodes for that?
On Tue, Jul 18, 2017 at 8:46 PM, Andy Shevchenko <andy.shevchenko@gmail.com> wrote: > On Tue, Jul 18, 2017 at 8:25 PM, Mark Salyzyn <salyzyn@android.com> wrote: >> Go directly to the rtc for persistent wall clock time and print. >> Useful if REALTIME is required to be logged in a low level power >> management function or when clock activities are suspended. An >> aid to permit user space alignment of kernel activities. >> >> Feature activated by CONFIG_RTC_SHOW_TIME. > > What's wrong with procfs device nodes for that? Ah, it's internal API, ok. Then would it be possible to use %pt [1] or alike? [1]: https://www.spinics.net/lists/kernel/msg2528401.html
Hi, On 18/07/2017 at 10:25:23 -0700, Mark Salyzyn wrote: > Go directly to the rtc for persistent wall clock time and print. > Useful if REALTIME is required to be logged in a low level power > management function or when clock activities are suspended. An > aid to permit user space alignment of kernel activities. > > Feature activated by CONFIG_RTC_SHOW_TIME. > > Signed-off-by: Mark Salyzyn <salyzyn@android.com> > --- > drivers/rtc/Kconfig | 11 +++++++++++ > drivers/rtc/rtc-lib.c | 16 ++++++++++++++++ > include/linux/rtc.h | 5 +++++ > 3 files changed, 32 insertions(+) > > diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig > index 72419ac2c52a..7c308605bf42 100644 > --- a/drivers/rtc/Kconfig > +++ b/drivers/rtc/Kconfig > @@ -5,6 +5,17 @@ > config RTC_LIB > bool > > +config RTC_SHOW_TIME > + bool "rtc_show_time instrumentation" > + select RTC_LIB > + help > + Activate rtc_show_time(const char *msg) wall clock time > + instrumentation. > + > + The instrumentation is used to help triage and synchronize > + kernel logs using CLOCK_MONOTONIC and user space activity > + logs utilizing CLOCK_REALTIME references. > + > config RTC_MC146818_LIB > bool > select RTC_LIB > diff --git a/drivers/rtc/rtc-lib.c b/drivers/rtc/rtc-lib.c > index 1ae7da5cfc60..676d6a83e843 100644 > --- a/drivers/rtc/rtc-lib.c > +++ b/drivers/rtc/rtc-lib.c > @@ -94,6 +94,22 @@ void rtc_time64_to_tm(time64_t time, struct rtc_time *tm) > } > EXPORT_SYMBOL(rtc_time64_to_tm); > > +#ifdef CONFIG_RTC_SHOW_TIME > +void rtc_show_time(const char *prefix_msg) > +{ > + struct timespec ts; > + struct rtc_time tm; > + > + getnstimeofday(&ts); > + rtc_time_to_tm(ts.tv_sec, &tm); Apart from using rtc_time_to_tm (and you should probably use rtc_time64_to_tm), none of this is actually related to the RTC subsystem. I feel like you should find another place to put that, maybe timekeeping_debug.c? > + pr_info("%s %d-%02d-%02d %02d:%02d:%02d.%09lu UTC\n", > + prefix_msg ? prefix_msg : "Time:", > + tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday, > + tm.tm_hour, tm.tm_min, tm.tm_sec, ts.tv_nsec); > +} > +EXPORT_SYMBOL(rtc_show_time); > +#endif > + > /* > * Does the rtc_time represent a valid date/time? > */ > diff --git a/include/linux/rtc.h b/include/linux/rtc.h > index 0a0f0d14a5fb..bf625e023799 100644 > --- a/include/linux/rtc.h > +++ b/include/linux/rtc.h > @@ -22,6 +22,11 @@ extern int rtc_year_days(unsigned int day, unsigned int month, unsigned int year > extern int rtc_valid_tm(struct rtc_time *tm); > extern time64_t rtc_tm_to_time64(struct rtc_time *tm); > extern void rtc_time64_to_tm(time64_t time, struct rtc_time *tm); > +#ifdef CONFIG_RTC_SHOW_TIME > +extern void rtc_show_time(const char *prefix_msg); > +#else > +#define rtc_show_time(prefix_msg) > +#endif > ktime_t rtc_tm_to_ktime(struct rtc_time tm); > struct rtc_time rtc_ktime_to_tm(ktime_t kt); > > -- > 2.13.2.932.g7449e964c-goog >
On 07/18/2017 10:52 AM, Alexandre Belloni wrote: > Hi, > > On 18/07/2017 at 10:25:23 -0700, Mark Salyzyn wrote: >> . . . > Apart from using rtc_time_to_tm (and you should probably use > rtc_time64_to_tm), none of this is actually related to the RTC > subsystem. I feel like you should find another place to put that, maybe > timekeeping_debug.c? Makes a lot of sense! -- Mark
On 07/18/2017 01:00 PM, Mark Salyzyn wrote: > On 07/18/2017 10:52 AM, Alexandre Belloni wrote: >> Hi, >> >> On 18/07/2017 at 10:25:23 -0700, Mark Salyzyn wrote: >>> . . . >> Apart from using rtc_time_to_tm (and you should probably use >> rtc_time64_to_tm), none of this is actually related to the RTC >> subsystem. I feel like you should find another place to put that, maybe >> timekeeping_debug.c? > Makes a lot of sense! > > -- Mark Ooops, timekeeping_debug.c is currently only to support a debugfs node. Perhaps a _new_ file in that hierarchy like kernel/time/rtc_show_time.c. -- Mark
diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig index 72419ac2c52a..7c308605bf42 100644 --- a/drivers/rtc/Kconfig +++ b/drivers/rtc/Kconfig @@ -5,6 +5,17 @@ config RTC_LIB bool +config RTC_SHOW_TIME + bool "rtc_show_time instrumentation" + select RTC_LIB + help + Activate rtc_show_time(const char *msg) wall clock time + instrumentation. + + The instrumentation is used to help triage and synchronize + kernel logs using CLOCK_MONOTONIC and user space activity + logs utilizing CLOCK_REALTIME references. + config RTC_MC146818_LIB bool select RTC_LIB diff --git a/drivers/rtc/rtc-lib.c b/drivers/rtc/rtc-lib.c index 1ae7da5cfc60..676d6a83e843 100644 --- a/drivers/rtc/rtc-lib.c +++ b/drivers/rtc/rtc-lib.c @@ -94,6 +94,22 @@ void rtc_time64_to_tm(time64_t time, struct rtc_time *tm) } EXPORT_SYMBOL(rtc_time64_to_tm); +#ifdef CONFIG_RTC_SHOW_TIME +void rtc_show_time(const char *prefix_msg) +{ + struct timespec ts; + struct rtc_time tm; + + getnstimeofday(&ts); + rtc_time_to_tm(ts.tv_sec, &tm); + pr_info("%s %d-%02d-%02d %02d:%02d:%02d.%09lu UTC\n", + prefix_msg ? prefix_msg : "Time:", + tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday, + tm.tm_hour, tm.tm_min, tm.tm_sec, ts.tv_nsec); +} +EXPORT_SYMBOL(rtc_show_time); +#endif + /* * Does the rtc_time represent a valid date/time? */ diff --git a/include/linux/rtc.h b/include/linux/rtc.h index 0a0f0d14a5fb..bf625e023799 100644 --- a/include/linux/rtc.h +++ b/include/linux/rtc.h @@ -22,6 +22,11 @@ extern int rtc_year_days(unsigned int day, unsigned int month, unsigned int year extern int rtc_valid_tm(struct rtc_time *tm); extern time64_t rtc_tm_to_time64(struct rtc_time *tm); extern void rtc_time64_to_tm(time64_t time, struct rtc_time *tm); +#ifdef CONFIG_RTC_SHOW_TIME +extern void rtc_show_time(const char *prefix_msg); +#else +#define rtc_show_time(prefix_msg) +#endif ktime_t rtc_tm_to_ktime(struct rtc_time tm); struct rtc_time rtc_ktime_to_tm(ktime_t kt);
Go directly to the rtc for persistent wall clock time and print. Useful if REALTIME is required to be logged in a low level power management function or when clock activities are suspended. An aid to permit user space alignment of kernel activities. Feature activated by CONFIG_RTC_SHOW_TIME. Signed-off-by: Mark Salyzyn <salyzyn@android.com> --- drivers/rtc/Kconfig | 11 +++++++++++ drivers/rtc/rtc-lib.c | 16 ++++++++++++++++ include/linux/rtc.h | 5 +++++ 3 files changed, 32 insertions(+)