| Message ID | 1344329006-10645-3-git-send-email-chenhui.zhao@freescale.com (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | Kumar Gala |
| Headers | show |
On Aug 7, 2012, at 3:43 AM, Zhao Chenhui wrote: > The cpufreq driver of mpc85xx will disable/enable cpu hotplug temporarily. > Therefore, the related functions should be exported. > > Signed-off-by: Zhao Chenhui <chenhui.zhao@freescale.com> > --- > include/linux/cpu.h | 4 ++++ > 1 files changed, 4 insertions(+), 0 deletions(-) Rafael, Srivatsa, Wanted to get your ack on export these functions for direct calling by arch code. - k > > diff --git a/include/linux/cpu.h b/include/linux/cpu.h > index ce7a074..df8f73d 100644 > --- a/include/linux/cpu.h > +++ b/include/linux/cpu.h > @@ -146,6 +146,8 @@ void notify_cpu_starting(unsigned int cpu); > extern void cpu_maps_update_begin(void); > extern void cpu_maps_update_done(void); > > +extern void cpu_hotplug_disable_before_freeze(void); > +extern void cpu_hotplug_enable_after_thaw(void); > #else /* CONFIG_SMP */ > > #define cpu_notifier(fn, pri) do { (void)(fn); } while (0) > @@ -167,6 +169,8 @@ static inline void cpu_maps_update_done(void) > { > } > > +static inline void cpu_hotplug_disable_before_freeze(void) {} > +static inline void cpu_hotplug_enable_after_thaw(void) {} > #endif /* CONFIG_SMP */ > extern struct bus_type cpu_subsys; > > -- > 1.6.4.1 >
On 08/07/2012 11:21 PM, Kumar Gala wrote: > > On Aug 7, 2012, at 3:43 AM, Zhao Chenhui wrote: > >> The cpufreq driver of mpc85xx will disable/enable cpu hotplug temporarily. >> Therefore, the related functions should be exported. >> >> Signed-off-by: Zhao Chenhui <chenhui.zhao@freescale.com> >> --- >> include/linux/cpu.h | 4 ++++ >> 1 files changed, 4 insertions(+), 0 deletions(-) > > Rafael, Srivatsa, > > Wanted to get your ack on export these functions for direct calling by arch code. > Why not just use get_online_cpus()/put_online_cpus()? In the case of suspend/resume/hibernation, we had introduced these CPU hotplug disable functions because we would end up doing CPU hotplug ourselves, further down the path. So if we did a get_online_cpus(), we would end up deadlocking ourselves. Whereas, the patch 4/4 looks like a straightforward case of wanting to simply disable CPU hotplug.. I don't see where you are doing CPU hotplug yourself in the path. So IMO, just get/put_online_cpus() should do. Regards, Srivatsa S. Bhat > >> >> diff --git a/include/linux/cpu.h b/include/linux/cpu.h >> index ce7a074..df8f73d 100644 >> --- a/include/linux/cpu.h >> +++ b/include/linux/cpu.h >> @@ -146,6 +146,8 @@ void notify_cpu_starting(unsigned int cpu); >> extern void cpu_maps_update_begin(void); >> extern void cpu_maps_update_done(void); >> >> +extern void cpu_hotplug_disable_before_freeze(void); >> +extern void cpu_hotplug_enable_after_thaw(void); >> #else /* CONFIG_SMP */ >> >> #define cpu_notifier(fn, pri) do { (void)(fn); } while (0) >> @@ -167,6 +169,8 @@ static inline void cpu_maps_update_done(void) >> { >> } >> >> +static inline void cpu_hotplug_disable_before_freeze(void) {} >> +static inline void cpu_hotplug_enable_after_thaw(void) {} >> #endif /* CONFIG_SMP */ >> extern struct bus_type cpu_subsys; >> >> -- >> 1.6.4.1 >> >
On Wed, Aug 08, 2012 at 11:43:22AM +0530, Srivatsa S. Bhat wrote: > On 08/07/2012 11:21 PM, Kumar Gala wrote: > > > > On Aug 7, 2012, at 3:43 AM, Zhao Chenhui wrote: > > > >> The cpufreq driver of mpc85xx will disable/enable cpu hotplug temporarily. > >> Therefore, the related functions should be exported. > >> > >> Signed-off-by: Zhao Chenhui <chenhui.zhao@freescale.com> > >> --- > >> include/linux/cpu.h | 4 ++++ > >> 1 files changed, 4 insertions(+), 0 deletions(-) > > > > Rafael, Srivatsa, > > > > Wanted to get your ack on export these functions for direct calling by arch code. > > > > Why not just use get_online_cpus()/put_online_cpus()? > > In the case of suspend/resume/hibernation, we had introduced these CPU hotplug disable > functions because we would end up doing CPU hotplug ourselves, further down the path. > So if we did a get_online_cpus(), we would end up deadlocking ourselves. Whereas, the > patch 4/4 looks like a straightforward case of wanting to simply disable CPU hotplug.. > I don't see where you are doing CPU hotplug yourself in the path. So IMO, just > get/put_online_cpus() should do. > > Regards, > Srivatsa S. Bhat > Thanks for your comment. I will try to use get/put_online_cpus() in my patch. -Chenhui
On Tue, Aug 07, 2012 at 04:43:25PM +0800, Zhao Chenhui wrote: > The cpufreq driver of mpc85xx will disable/enable cpu hotplug temporarily. > Therefore, the related functions should be exported. > > Signed-off-by: Zhao Chenhui <chenhui.zhao@freescale.com> > --- > include/linux/cpu.h | 4 ++++ > 1 files changed, 4 insertions(+), 0 deletions(-) > > diff --git a/include/linux/cpu.h b/include/linux/cpu.h > index ce7a074..df8f73d 100644 > --- a/include/linux/cpu.h > +++ b/include/linux/cpu.h > @@ -146,6 +146,8 @@ void notify_cpu_starting(unsigned int cpu); > extern void cpu_maps_update_begin(void); > extern void cpu_maps_update_done(void); > > +extern void cpu_hotplug_disable_before_freeze(void); > +extern void cpu_hotplug_enable_after_thaw(void); > #else /* CONFIG_SMP */ > > #define cpu_notifier(fn, pri) do { (void)(fn); } while (0) > @@ -167,6 +169,8 @@ static inline void cpu_maps_update_done(void) > { > } > > +static inline void cpu_hotplug_disable_before_freeze(void) {} > +static inline void cpu_hotplug_enable_after_thaw(void) {} > #endif /* CONFIG_SMP */ > extern struct bus_type cpu_subsys; > > -- > 1.6.4.1 > Hi kumar, I will not use these API in the 4/4 patch. please ignore this patch. -Chenhui
diff --git a/include/linux/cpu.h b/include/linux/cpu.h index ce7a074..df8f73d 100644 --- a/include/linux/cpu.h +++ b/include/linux/cpu.h @@ -146,6 +146,8 @@ void notify_cpu_starting(unsigned int cpu); extern void cpu_maps_update_begin(void); extern void cpu_maps_update_done(void); +extern void cpu_hotplug_disable_before_freeze(void); +extern void cpu_hotplug_enable_after_thaw(void); #else /* CONFIG_SMP */ #define cpu_notifier(fn, pri) do { (void)(fn); } while (0) @@ -167,6 +169,8 @@ static inline void cpu_maps_update_done(void) { } +static inline void cpu_hotplug_disable_before_freeze(void) {} +static inline void cpu_hotplug_enable_after_thaw(void) {} #endif /* CONFIG_SMP */ extern struct bus_type cpu_subsys;
The cpufreq driver of mpc85xx will disable/enable cpu hotplug temporarily. Therefore, the related functions should be exported. Signed-off-by: Zhao Chenhui <chenhui.zhao@freescale.com> --- include/linux/cpu.h | 4 ++++ 1 files changed, 4 insertions(+), 0 deletions(-)