* [PATCH] arm: kernel: utilize hrtimer based broadcast @ 2015-07-17 9:11 Alison Wang 2015-10-27 2:58 ` Huan Wang 2015-10-27 8:18 ` Mark Rutland 0 siblings, 2 replies; 11+ messages in thread From: Alison Wang @ 2015-07-17 9:11 UTC (permalink / raw) To: linux-arm-kernel Hrtimer based broadcast is used on ARM platform. It can be registered as the tick broadcast device in the absence of a real external clock device. Signed-off-by: Alison Wang <alison.wang@freescale.com> --- arch/arm/kernel/time.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/arm/kernel/time.c b/arch/arm/kernel/time.c index a66e37e..a9bc73c 100644 --- a/arch/arm/kernel/time.c +++ b/arch/arm/kernel/time.c @@ -12,6 +12,7 @@ * reading the RTC at bootup, etc... */ #include <linux/clk-provider.h> +#include <linux/clockchips.h> #include <linux/clocksource.h> #include <linux/errno.h> #include <linux/export.h> @@ -121,5 +122,7 @@ void __init time_init(void) of_clk_init(NULL); #endif clocksource_of_init(); + + tick_setup_hrtimer_broadcast(); } } -- 2.1.0.27.g96db324 ^ permalink raw reply related [flat|nested] 11+ messages in thread
* [PATCH] arm: kernel: utilize hrtimer based broadcast 2015-07-17 9:11 [PATCH] arm: kernel: utilize hrtimer based broadcast Alison Wang @ 2015-10-27 2:58 ` Huan Wang 2015-10-27 8:18 ` Mark Rutland 1 sibling, 0 replies; 11+ messages in thread From: Huan Wang @ 2015-10-27 2:58 UTC (permalink / raw) To: linux-arm-kernel Hi, Mark, Could you comment this patch? It is based on your suggestion in https://patchwork.kernel.org/patch/6764231/ . Thanks. Best Regards, Alison Wang > -----Original Message----- > From: Alison Wang [mailto:b18965 at freescale.com] > Sent: Friday, July 17, 2015 5:12 PM > To: mark.rutland at arm.com; linux-arm-kernel at lists.infradead.org; linux- > kernel at vger.kernel.org > Cc: Wang Huan-B18965 > Subject: [PATCH] arm: kernel: utilize hrtimer based broadcast > > Hrtimer based broadcast is used on ARM platform. It can be registered as > the tick broadcast device in the absence of a real external clock device. > > Signed-off-by: Alison Wang <alison.wang@freescale.com> > --- > arch/arm/kernel/time.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/arch/arm/kernel/time.c b/arch/arm/kernel/time.c index > a66e37e..a9bc73c 100644 > --- a/arch/arm/kernel/time.c > +++ b/arch/arm/kernel/time.c > @@ -12,6 +12,7 @@ > * reading the RTC at bootup, etc... > */ > #include <linux/clk-provider.h> > +#include <linux/clockchips.h> > #include <linux/clocksource.h> > #include <linux/errno.h> > #include <linux/export.h> > @@ -121,5 +122,7 @@ void __init time_init(void) > of_clk_init(NULL); > #endif > clocksource_of_init(); > + > + tick_setup_hrtimer_broadcast(); > } > } > -- > 2.1.0.27.g96db324 ^ permalink raw reply [flat|nested] 11+ messages in thread
* [PATCH] arm: kernel: utilize hrtimer based broadcast 2015-07-17 9:11 [PATCH] arm: kernel: utilize hrtimer based broadcast Alison Wang 2015-10-27 2:58 ` Huan Wang @ 2015-10-27 8:18 ` Mark Rutland 2015-11-06 6:35 ` Huan Wang 2015-12-28 7:18 ` Huan Wang 1 sibling, 2 replies; 11+ messages in thread From: Mark Rutland @ 2015-10-27 8:18 UTC (permalink / raw) To: linux-arm-kernel On Fri, Jul 17, 2015 at 10:11:52AM +0100, Alison Wang wrote: > Hrtimer based broadcast is used on ARM platform. It can be > registered as the tick broadcast device in the absence of > a real external clock device. > > Signed-off-by: Alison Wang <alison.wang@freescale.com> This looks sensible to me. FWIW: Acked-by: Mark Rutland <mark.rutland@arm.com> Thanks, Mark. > --- > arch/arm/kernel/time.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/arch/arm/kernel/time.c b/arch/arm/kernel/time.c > index a66e37e..a9bc73c 100644 > --- a/arch/arm/kernel/time.c > +++ b/arch/arm/kernel/time.c > @@ -12,6 +12,7 @@ > * reading the RTC at bootup, etc... > */ > #include <linux/clk-provider.h> > +#include <linux/clockchips.h> > #include <linux/clocksource.h> > #include <linux/errno.h> > #include <linux/export.h> > @@ -121,5 +122,7 @@ void __init time_init(void) > of_clk_init(NULL); > #endif > clocksource_of_init(); > + > + tick_setup_hrtimer_broadcast(); > } > } > -- > 2.1.0.27.g96db324 > ^ permalink raw reply [flat|nested] 11+ messages in thread
* [PATCH] arm: kernel: utilize hrtimer based broadcast 2015-10-27 8:18 ` Mark Rutland @ 2015-11-06 6:35 ` Huan Wang 2015-12-28 7:18 ` Huan Wang 1 sibling, 0 replies; 11+ messages in thread From: Huan Wang @ 2015-11-06 6:35 UTC (permalink / raw) To: linux-arm-kernel Hi, Could you help to review this patch? Thanks. Best Regards, Alison Wang > On Fri, Jul 17, 2015 at 10:11:52AM +0100, Alison Wang wrote: > > Hrtimer based broadcast is used on ARM platform. It can be registered > > as the tick broadcast device in the absence of a real external clock; > > device. > > > > Signed-off-by: Alison Wang <alison.wang@freescale.com> > > This looks sensible to me. FWIW: > > Acked-by: Mark Rutland <mark.rutland@arm.com> > > Thanks, > Mark. > > > --- > > arch/arm/kernel/time.c | 3 +++ > > 1 file changed, 3 insertions(+) > > > > diff --git a/arch/arm/kernel/time.c b/arch/arm/kernel/time.c index > > a66e37e..a9bc73c 100644 > > --- a/arch/arm/kernel/time.c > > +++ b/arch/arm/kernel/time.c > > @@ -12,6 +12,7 @@ > > * reading the RTC at bootup, etc... > > */ > > #include <linux/clk-provider.h> > > +#include <linux/clockchips.h> > > #include <linux/clocksource.h> > > #include <linux/errno.h> > > #include <linux/export.h> > > @@ -121,5 +122,7 @@ void __init time_init(void) > > of_clk_init(NULL); > > #endif > > clocksource_of_init(); > > + > > + tick_setup_hrtimer_broadcast(); > > } > > } > > -- > > 2.1.0.27.g96db324 > > ^ permalink raw reply [flat|nested] 11+ messages in thread
* [PATCH] arm: kernel: utilize hrtimer based broadcast 2015-10-27 8:18 ` Mark Rutland 2015-11-06 6:35 ` Huan Wang @ 2015-12-28 7:18 ` Huan Wang 2015-12-28 11:54 ` Arnd Bergmann 1 sibling, 1 reply; 11+ messages in thread From: Huan Wang @ 2015-12-28 7:18 UTC (permalink / raw) To: linux-arm-kernel Hi, Arnd, Could you help to review the following patch? Thanks. Best Regards, Alison Wang > On Fri, Jul 17, 2015 at 10:11:52AM +0100, Alison Wang wrote: > > Hrtimer based broadcast is used on ARM platform. It can be registered > > as the tick broadcast device in the absence of a real external clock > > device. > > > > Signed-off-by: Alison Wang <alison.wang@freescale.com> > > This looks sensible to me. FWIW: > > Acked-by: Mark Rutland <mark.rutland@arm.com> > > Thanks, > Mark. > > > --- > > arch/arm/kernel/time.c | 3 +++ > > 1 file changed, 3 insertions(+) > > > > diff --git a/arch/arm/kernel/time.c b/arch/arm/kernel/time.c index > > a66e37e..a9bc73c 100644 > > --- a/arch/arm/kernel/time.c > > +++ b/arch/arm/kernel/time.c > > @@ -12,6 +12,7 @@ > > * reading the RTC at bootup, etc... > > */ > > #include <linux/clk-provider.h> > > +#include <linux/clockchips.h> > > #include <linux/clocksource.h> > > #include <linux/errno.h> > > #include <linux/export.h> > > @@ -121,5 +122,7 @@ void __init time_init(void) > > of_clk_init(NULL); > > #endif > > clocksource_of_init(); > > + > > + tick_setup_hrtimer_broadcast(); > > } > > } > > -- > > 2.1.0.27.g96db324 > > ^ permalink raw reply [flat|nested] 11+ messages in thread
* [PATCH] arm: kernel: utilize hrtimer based broadcast 2015-12-28 7:18 ` Huan Wang @ 2015-12-28 11:54 ` Arnd Bergmann 2015-12-29 13:54 ` Thomas Gleixner 0 siblings, 1 reply; 11+ messages in thread From: Arnd Bergmann @ 2015-12-28 11:54 UTC (permalink / raw) To: linux-arm-kernel On Monday 28 December 2015 07:18:58 Huan Wang wrote: > Hi, Arnd, > > Could you help to review the following patch? Thanks. > Hi Alison, I'm sorry but I understand very little of this particular area of the kernel. I've added Daniel Lezcano, John Stultz and Thomas Gleixner to Cc, they all know this much better than I do and one of them should be able to comment after their Christmas break. Arnd > > On Fri, Jul 17, 2015 at 10:11:52AM +0100, Alison Wang wrote: > > > Hrtimer based broadcast is used on ARM platform. It can be registered > > > as the tick broadcast device in the absence of a real external clock > > > device. > > > > > > Signed-off-by: Alison Wang <alison.wang@freescale.com> > > > > This looks sensible to me. FWIW: > > > > Acked-by: Mark Rutland <mark.rutland@arm.com> > > > > Thanks, > > Mark. > > > > > --- > > > arch/arm/kernel/time.c | 3 +++ > > > 1 file changed, 3 insertions(+) > > > > > > diff --git a/arch/arm/kernel/time.c b/arch/arm/kernel/time.c index > > > a66e37e..a9bc73c 100644 > > > --- a/arch/arm/kernel/time.c > > > +++ b/arch/arm/kernel/time.c > > > @@ -12,6 +12,7 @@ > > > * reading the RTC at bootup, etc... > > > */ > > > #include <linux/clk-provider.h> > > > +#include <linux/clockchips.h> > > > #include <linux/clocksource.h> > > > #include <linux/errno.h> > > > #include <linux/export.h> > > > @@ -121,5 +122,7 @@ void __init time_init(void) > > > of_clk_init(NULL); > > > #endif > > > clocksource_of_init(); > > > + > > > + tick_setup_hrtimer_broadcast(); > > > } > > > } ^ permalink raw reply [flat|nested] 11+ messages in thread
* [PATCH] arm: kernel: utilize hrtimer based broadcast 2015-12-28 11:54 ` Arnd Bergmann @ 2015-12-29 13:54 ` Thomas Gleixner 2016-01-02 10:29 ` Russell King - ARM Linux 0 siblings, 1 reply; 11+ messages in thread From: Thomas Gleixner @ 2015-12-29 13:54 UTC (permalink / raw) To: linux-arm-kernel On Mon, 28 Dec 2015, Arnd Bergmann wrote: > On Monday 28 December 2015 07:18:58 Huan Wang wrote: > > Hi, Arnd, > > > > Could you help to review the following patch? Thanks. > > > > Hi Alison, > > I'm sorry but I understand very little of this particular area of the kernel. > > I've added Daniel Lezcano, John Stultz and Thomas Gleixner to Cc, they all > know this much better than I do and one of them should be able to comment after > their Christmas break. I have no real opinion about that patch. It does no harm to unconditionally setup the hrtimer based broadcast even if it's never used. Up to the arch maintainer to decide. Thanks, tglx > > > On Fri, Jul 17, 2015 at 10:11:52AM +0100, Alison Wang wrote: > > > > Hrtimer based broadcast is used on ARM platform. It can be registered > > > > as the tick broadcast device in the absence of a real external clock > > > > device. > > > > > > > > Signed-off-by: Alison Wang <alison.wang@freescale.com> > > > > > > This looks sensible to me. FWIW: > > > > > > Acked-by: Mark Rutland <mark.rutland@arm.com> > > > > > > Thanks, > > > Mark. > > > > > > > --- > > > > arch/arm/kernel/time.c | 3 +++ > > > > 1 file changed, 3 insertions(+) > > > > > > > > diff --git a/arch/arm/kernel/time.c b/arch/arm/kernel/time.c index > > > > a66e37e..a9bc73c 100644 > > > > --- a/arch/arm/kernel/time.c > > > > +++ b/arch/arm/kernel/time.c > > > > @@ -12,6 +12,7 @@ > > > > * reading the RTC at bootup, etc... > > > > */ > > > > #include <linux/clk-provider.h> > > > > +#include <linux/clockchips.h> > > > > #include <linux/clocksource.h> > > > > #include <linux/errno.h> > > > > #include <linux/export.h> > > > > @@ -121,5 +122,7 @@ void __init time_init(void) > > > > of_clk_init(NULL); > > > > #endif > > > > clocksource_of_init(); > > > > + > > > > + tick_setup_hrtimer_broadcast(); > > > > } > > > > } > > > ^ permalink raw reply [flat|nested] 11+ messages in thread
* [PATCH] arm: kernel: utilize hrtimer based broadcast 2015-12-29 13:54 ` Thomas Gleixner @ 2016-01-02 10:29 ` Russell King - ARM Linux 2016-01-05 9:42 ` Thomas Gleixner 0 siblings, 1 reply; 11+ messages in thread From: Russell King - ARM Linux @ 2016-01-02 10:29 UTC (permalink / raw) To: linux-arm-kernel On Tue, Dec 29, 2015 at 02:54:10PM +0100, Thomas Gleixner wrote: > On Mon, 28 Dec 2015, Arnd Bergmann wrote: > > > On Monday 28 December 2015 07:18:58 Huan Wang wrote: > > > Hi, Arnd, > > > > > > Could you help to review the following patch? Thanks. > > > > > > > Hi Alison, > > > > I'm sorry but I understand very little of this particular area of the kernel. > > > > I've added Daniel Lezcano, John Stultz and Thomas Gleixner to Cc, they all > > know this much better than I do and one of them should be able to comment after > > their Christmas break. > > I have no real opinion about that patch. It does no harm to unconditionally > setup the hrtimer based broadcast even if it's never used. > > Up to the arch maintainer to decide. That's really not fair to keep shovelling these kinds of decisions onto architecture maintainers without any kind of explanation about how an architecture maintainer should make such a decision. Do I roll a 6-face dice, and if it gives an odd number, I apply this patch, otherwise I reject it? Is there a technical basis for making the decision? If so, please explain what the technical arguments are against having or not having this change. Thanks. -- RMK's Patch system: http://www.arm.linux.org.uk/developer/patches/ FTTC broadband for 0.8mile line: currently at 9.6Mbps down 400kbps up according to speedtest.net. ^ permalink raw reply [flat|nested] 11+ messages in thread
* [PATCH] arm: kernel: utilize hrtimer based broadcast 2016-01-02 10:29 ` Russell King - ARM Linux @ 2016-01-05 9:42 ` Thomas Gleixner 2017-12-01 3:33 ` Alison Wang 2019-04-03 2:36 ` Yang Li 0 siblings, 2 replies; 11+ messages in thread From: Thomas Gleixner @ 2016-01-05 9:42 UTC (permalink / raw) To: linux-arm-kernel On Sat, 2 Jan 2016, Russell King - ARM Linux wrote: > On Tue, Dec 29, 2015 at 02:54:10PM +0100, Thomas Gleixner wrote: > > I have no real opinion about that patch. It does no harm to unconditionally > > setup the hrtimer based broadcast even if it's never used. > > > > Up to the arch maintainer to decide. > > That's really not fair to keep shovelling these kinds of decisions onto > architecture maintainers without any kind of explanation about how an > architecture maintainer should make such a decision. > > Do I roll a 6-face dice, and if it gives an odd number, I apply this > patch, otherwise I reject it? > > Is there a technical basis for making the decision? If so, please > explain what the technical arguments are against having or not having > this change. The hrtimer based broadcast device is used when you have per cpu timers which stop in deeper power states, but you have no other timer hardware on the chip which can backup the per cpu timer in deep power states. The trick is that it emulates a timer hardware via a hrtimer and then tells the cpu idle code not to go into deep power states on the cpu which owns that hrtimer. All other cpus can go as deep as they want and still get woken up. The only downside of adding this unconditionally is extra code in case that it is not needed on a particular platform. Hope that helps. tglx ^ permalink raw reply [flat|nested] 11+ messages in thread
* [PATCH] arm: kernel: utilize hrtimer based broadcast 2016-01-05 9:42 ` Thomas Gleixner @ 2017-12-01 3:33 ` Alison Wang 2019-04-03 2:36 ` Yang Li 1 sibling, 0 replies; 11+ messages in thread From: Alison Wang @ 2017-12-01 3:33 UTC (permalink / raw) To: linux-arm-kernel Hi, Russell, > On Sat, 2 Jan 2016, Russell King - ARM Linux wrote: > > On Tue, Dec 29, 2015 at 02:54:10PM +0100, Thomas Gleixner wrote: > > > I have no real opinion about that patch. It does no harm to > > > unconditionally setup the hrtimer based broadcast even if it's never > used. > > > > > > Up to the arch maintainer to decide. > > > > That's really not fair to keep shovelling these kinds of decisions > > onto architecture maintainers without any kind of explanation about > > how an architecture maintainer should make such a decision. > > > > Do I roll a 6-face dice, and if it gives an odd number, I apply this > > patch, otherwise I reject it? > > > > Is there a technical basis for making the decision? If so, please > > explain what the technical arguments are against having or not having > > this change. > > The hrtimer based broadcast device is used when you have per cpu timers > which stop in deeper power states, but you have no other timer hardware on > the chip which can backup the per cpu timer in deep power states. The > trick is that it emulates a timer hardware via a hrtimer and then tells > the cpu idle code not to go into deep power states on the cpu which owns > that hrtimer. All other cpus can go as deep as they want and still get > woken up. > > The only downside of adding this unconditionally is extra code in case > that it is not needed on a particular platform. > > Hope that helps. > [Alison Wang] What's your opinion about this explanation? Is this patch acceptable? Best Regards, Alison Wang ^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH] arm: kernel: utilize hrtimer based broadcast 2016-01-05 9:42 ` Thomas Gleixner 2017-12-01 3:33 ` Alison Wang @ 2019-04-03 2:36 ` Yang Li 1 sibling, 0 replies; 11+ messages in thread From: Yang Li @ 2019-04-03 2:36 UTC (permalink / raw) To: Thomas Gleixner Cc: mark.rutland@arm.com, Daniel Lezcano, Russell King - ARM Linux, Arnd Bergmann, Huan Wang, Huan Wang, linux-kernel@vger.kernel.org, John Stultz, LAK On Tue, Jan 5, 2016 at 3:46 AM Thomas Gleixner <tglx@linutronix.de> wrote: > > On Sat, 2 Jan 2016, Russell King - ARM Linux wrote: > > On Tue, Dec 29, 2015 at 02:54:10PM +0100, Thomas Gleixner wrote: > > > I have no real opinion about that patch. It does no harm to unconditionally > > > setup the hrtimer based broadcast even if it's never used. > > > > > > Up to the arch maintainer to decide. > > > > That's really not fair to keep shovelling these kinds of decisions onto > > architecture maintainers without any kind of explanation about how an > > architecture maintainer should make such a decision. > > > > Do I roll a 6-face dice, and if it gives an odd number, I apply this > > patch, otherwise I reject it? > > > > Is there a technical basis for making the decision? If so, please > > explain what the technical arguments are against having or not having > > this change. > > The hrtimer based broadcast device is used when you have per cpu timers which > stop in deeper power states, but you have no other timer hardware on the chip > which can backup the per cpu timer in deep power states. The trick is that it > emulates a timer hardware via a hrtimer and then tells the cpu idle code not > to go into deep power states on the cpu which owns that hrtimer. All other > cpus can go as deep as they want and still get woken up. > > The only downside of adding this unconditionally is extra code in case that it > is not needed on a particular platform. > > Hope that helps. Hi Russell, This has been pending for so long time. I assume this is an ack from Thomas. And given the same thing has been added for arm64 and powerpc architecture, can you also merge this for ARM? Regards, Leo _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel ^ permalink raw reply [flat|nested] 11+ messages in thread
end of thread, other threads:[~2019-04-03 2:37 UTC | newest] Thread overview: 11+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2015-07-17 9:11 [PATCH] arm: kernel: utilize hrtimer based broadcast Alison Wang 2015-10-27 2:58 ` Huan Wang 2015-10-27 8:18 ` Mark Rutland 2015-11-06 6:35 ` Huan Wang 2015-12-28 7:18 ` Huan Wang 2015-12-28 11:54 ` Arnd Bergmann 2015-12-29 13:54 ` Thomas Gleixner 2016-01-02 10:29 ` Russell King - ARM Linux 2016-01-05 9:42 ` Thomas Gleixner 2017-12-01 3:33 ` Alison Wang 2019-04-03 2:36 ` Yang Li
This is a public inbox, see mirroring instructions for how to clone and mirror all data and code used for this inbox; as well as URLs for NNTP newsgroup(s).