Hi, all In xen code, some place will call NOW() function. Now I do not know how to know the unit for this function. There are two places given the definition for this function NOW() one is xen-4.2.1/extras/mini-os/include/Time.h In this file xen-4.2.1/extras/mini-os/include/Time.h, from the comment NOW() the unit for time is /*System Time 64 bit value containing the nanoseconds elapsed since boot time.*/ the other is xen-4.2.1/xen/include/xen/Time.h In xen schedule related places, they call the function NOW() in the xen-4.2.1/xen/include/xen/Time.h. At first, I think NOW() the unit for time in xen-4.2.1/xen/include/xen/Time.h file, should also nanosecond. However, From here, set_timer(&spc->ticker, NOW() + MICROSECS(prv->tick_period_us) ); In the function csched_alloc_pdata(), it seems the unit is microsecs. Now I am confused with it. If someone knows the answer, please let me know. Thank you in advance! _______________________________________________ Xen-users mailing list Xen-users@lists.xen.org http://lists.xen.org/xen-users
On Tue, Jul 9, 2013 at 9:30 AM, 张伟 <zhangwqh@126.com> wrote:> Hi, all > > In xen code, some place will call NOW() function. Now I do not know how to > know the unit for this function. > There are two places given the definition for this function NOW() > one is xen-4.2.1/extras/mini-os/include/Time.h > In this file xen-4.2.1/extras/mini-os/include/Time.h, from the comment > NOW() the unit for time is > /*System Time > 64 bit value containing the nanoseconds elapsed since boot time.*/ > the other is xen-4.2.1/xen/include/xen/Time.h > In xen schedule related places, they call the function NOW() in the > xen-4.2.1/xen/include/xen/Time.h. > > At first, I think NOW() the unit for time in > xen-4.2.1/xen/include/xen/Time.h file, should also nanosecond. > However, From here, > set_timer(&spc->ticker, NOW() + MICROSECS(prv->tick_period_us) ); In the > function csched_alloc_pdata(), it seems the unit is microsecs.#define MICROSECS(_us) (((s_time_t)(_us)) * 1000UL ) To nanosecond...> > Now I am confused with it. > > If someone knows the answer, please let me know. Thank you in advance! > > > > > _______________________________________________ > Xen-users mailing list > Xen-users@lists.xen.org > http://lists.xen.org/xen-users_______________________________________________ Xen-users mailing list Xen-users@lists.xen.org http://lists.xen.org/xen-users
Thank you very much! At first, I did not carefully read these macros and I have a misunderstanding- at first I thought these macros change the unit to related unit. Eg, #define MICROSECS(_us) (((s_time_t)(_us)) * 1000UL ) change to microsecs. Thank you for your guidance. These macros change from the related unit to nano. 在 2013-07-09 21:53:31，"jinho hwang" <hwang.jinho@gmail.com> 写道：>On Tue, Jul 9, 2013 at 9:30 AM, 张伟 <zhangwqh@126.com> wrote: >> Hi, all >> >> In xen code, some place will call NOW() function. Now I do not know how to >> know the unit for this function. >> There are two places given the definition for this function NOW() >> one is xen-4.2.1/extras/mini-os/include/Time.h >> In this file xen-4.2.1/extras/mini-os/include/Time.h, from the comment >> NOW() the unit for time is >> /*System Time >> 64 bit value containing the nanoseconds elapsed since boot time.*/ >> the other is xen-4.2.1/xen/include/xen/Time.h >> In xen schedule related places, they call the function NOW() in the >> xen-4.2.1/xen/include/xen/Time.h. >> >> At first, I think NOW() the unit for time in >> xen-4.2.1/xen/include/xen/Time.h file, should also nanosecond. >> However, From here, >> set_timer(&spc->ticker, NOW() + MICROSECS(prv->tick_period_us) ); In the >> function csched_alloc_pdata(), it seems the unit is microsecs. > >#define MICROSECS(_us) (((s_time_t)(_us)) * 1000UL ) > >To nanosecond... > >> >> Now I am confused with it. >> >> If someone knows the answer, please let me know. Thank you in advance! >> >> >> >> >> _______________________________________________ >> Xen-users mailing list >> Xen-users@lists.xen.org >> http://lists.xen.org/xen-users > >_______________________________________________ >Xen-users mailing list >Xen-users@lists.xen.org >http://lists.xen.org/xen-users_______________________________________________ Xen-users mailing list Xen-users@lists.xen.org http://lists.xen.org/xen-users