From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <4C76462C.8050408@domain.hid> Date: Thu, 26 Aug 2010 12:47:08 +0200 From: Jan Kiszka MIME-Version: 1.0 References: <1278071401-13880-1-git-send-email-wolfgang.mauerer@domain.hid> <1278071401-13880-2-git-send-email-wolfgang.mauerer@domain.hid> <1282725843.1709.12.camel@domain.hid> <4C74D948.6010906@domain.hid> <1282726435.1709.22.camel@domain.hid> <4C74DB38.3010104@domain.hid> <1282727242.1709.26.camel@domain.hid> <4C74E022.8030105@domain.hid> <1282728443.1709.46.camel@domain.hid> <4C74EF8B.5090704@domain.hid> <1282735410.1709.129.camel@domain.hid> <4C763627.6010907@domain.hid> <1282819064.1709.151.camel@domain.hid> In-Reply-To: <1282819064.1709.151.camel@domain.hid> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Subject: Re: [Adeos-main] [PATCH 1/2] ipipe: Pass NTP-corrected time information from Linux to higher domains List-Id: General discussion about Adeos List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Philippe Gerum Cc: "adeos-main@gna.org" , "Mauerer, Wolfgang" Philippe Gerum wrote: > On Thu, 2010-08-26 at 11:38 +0200, Jan Kiszka wrote: >> Philippe Gerum wrote: >>> On Wed, 2010-08-25 at 12:25 +0200, Jan Kiszka wrote: >>>> Philippe Gerum wrote: >>>>> On Wed, 2010-08-25 at 11:19 +0200, Jan Kiszka wrote: >>>>>> Philippe Gerum wrote: >>>>>>> On Wed, 2010-08-25 at 10:58 +0200, Jan Kiszka wrote: >>>>>>>> Philippe Gerum wrote: >>>>>>>>> On Wed, 2010-08-25 at 10:50 +0200, Jan Kiszka wrote: >>>>>>>>>> Philippe Gerum wrote: >>>>>>>>>>> On Fri, 2010-07-02 at 13:50 +0200, Wolfgang Mauerer wrote: >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>>> diff --git a/include/linux/ipipe_tickdev.h b/include/linux/ipipe_tickdev.h >>>>>>>>>>>> index 4a1cb1b..86f13e0 100644 >>>>>>>>>>>> --- a/include/linux/ipipe_tickdev.h >>>>>>>>>>>> +++ b/include/linux/ipipe_tickdev.h >>>>>>>>>>>> @@ -25,6 +25,7 @@ >>>>>>>>>>>> #if defined(CONFIG_IPIPE) && defined(CONFIG_GENERIC_CLOCKEVENTS) >>>>>>>>>>> Since we should have CONFIG_HAVE_IPIPE_HOSTRT by now, let's use it. >>>>>>>>>> Don't get yet how this fits here. >>>>>>>>> arch-dep would define CONFIG_HAVE_IPIPE_HOSTRT [if IPIPE] >>>>>>>>> >>>>>>>> Still don't see the relation to the line you cited above. >>>>>>>> >>>>>>> That is because you chose to have CONFIG_IPIPE_HOSTRT and >>>>>>> CONFIG_HAVE_IPIPE_HOSTRT. I would have only defined the latter, the way >>>>>>> you define the former. I'm looking for the hostrt support to be compiled >>>>>>> in if CONFIG_HAVE_IPIPE_HOSTRT is available from the arch-dep section, >>>>>>> so we don't need CONFIG_IPIPE_HOSTRT. Generic bits may depend on HAVE_* >>>>>>> as well. >>>>>> First of all, the code you cited _above_ is not changed by our patches, >>>>>> so the context still puzzles me (but maybe you are referring to some >>>>>> other place in fact). >>>>> Patch v2 says: >>>>> >>>>> diff --git a/kernel/ipipe/Kconfig b/kernel/ipipe/Kconfig >>>>> index de5e6a3..bc7a00c 100644 >>>>> --- a/kernel/ipipe/Kconfig >>>>> +++ b/kernel/ipipe/Kconfig >>>>> @@ -33,3 +33,10 @@ config IPIPE_UNMASKED_CONTEXT_SWITCH >>>>> bool >>>>> depends on IPIPE >>>>> default n >>>>> + >>>>> +config HAVE_IPIPE_HOSTRT >>>>> + bool >>>>> + >>>>> +config IPIPE_HOSTRT >>>>> + def_bool y >>>>> + depends on HAVE_IPIPE_HOSTRT && IPIPE >>>>> >>>>> So what's your point? >>>>> >>>>>> Second, CONFIG_HAVE_IPIPE_HOSTRT is designed to be set independently of >>>>>> CONFIG_IPIPE - it's a static arch feature like all the other >>>>>> CONFIG_HAVE_* in arch/*/Kconfig. So it takes a second, generically >>>>>> defined CONFIG switch if the generic support also depends on >>>>>> CONFIG_IPIPE like in this case. >>>>> Which does not make any sense. We don't want to make this selectable at >>>>> all. Mainline has CONFIG_HAVE_SYSCALL_WRAPPERS for instance, and you >>>>> won't find any CONFIG_SYSCALL_WRAPPERS, because it makes no sense not to >>>>> use them when the architecture _have_ them. It goes exactly the same way >>>>> with hostrt. >>>> Don't find your example. >>> I just did: >>> find . -name 'Kconfig*' -print |xargs grep SYSCALL_WRAPPERS >> Ah, now I see. >> >>>> But maybe you should have a look at >>>> [HAVE_]USER_RETURN_NOTIFIER (and maybe I should push [HAVE_]IPIPE_HOSTRT >>>> into arch/Kconfig). >>> And select it conditionally on IPIPE in arch/x86/Kconfig? why not. >> I can change this if you want us to, but I think it would be better to >> have the generic dependency on IPIPE in a generic Kconfig - not every >> arch version. > > What I mean is: > > diff --git a/arch/Kconfig b/arch/Kconfig > index acda512..1b87a53 100644 > --- a/arch/Kconfig > +++ b/arch/Kconfig > @@ -151,4 +151,7 @@ config HAVE_MIXED_BREAKPOINTS_REGS > config HAVE_USER_RETURN_NOTIFIER > bool > > +config HAVE_IPIPE_HOSTRT > + bool > + > source "kernel/gcov/Kconfig" > diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig > index dcb0593..96ab0f4 100644 > --- a/arch/x86/Kconfig > +++ b/arch/x86/Kconfig > @@ -58,6 +58,7 @@ config X86 > select ANON_INODES > select HAVE_ARCH_KMEMCHECK > select HAVE_USER_RETURN_NOTIFIER > + select HAVE_IPIPE_HOSTRT if IPIPE > > config INSTRUCTION_DECODER > def_bool (KPROBES || PERF_EVENTS) > I fully understood what you meant, and to end this discussion I already implemented it. We will just have to make sure that every arch properly adds the required "if IPIPE" suffix. Jan -- Siemens AG, Corporate Technology, CT T DE IT 1 Corporate Competence Center Embedded Linux