RE: [PATCH v2 0/2] Drivers: hv: vmbus: use cpu_hotplug_enable/disable for CPU offlining prevention

From: KY Srinivasan
Date: Wed May 27 2015 - 10:37:23 EST




> -----Original Message-----
> From: Vitaly Kuznetsov [mailto:vkuznets@xxxxxxxxxx]
> Sent: Wednesday, May 27, 2015 2:15 AM
> To: KY Srinivasan
> Cc: devel@xxxxxxxxxxxxxxxxxxxxxx; Haiyang Zhang; linux-
> kernel@xxxxxxxxxxxxxxx; Dexuan Cui; Ingo Molnar; Paul E. McKenney; Rafael
> J. Wysocki; Peter Zijlstra; Thomas Gleixner; Radim KrÄmÃÅ
> Subject: Re: [PATCH v2 0/2] Drivers: hv: vmbus: use
> cpu_hotplug_enable/disable for CPU offlining prevention
>
> KY Srinivasan <kys@xxxxxxxxxxxxx> writes:
>
> >> -----Original Message-----
> >> From: Vitaly Kuznetsov [mailto:vkuznets@xxxxxxxxxx]
> >> Sent: Thursday, May 21, 2015 9:22 AM
> >> To: devel@xxxxxxxxxxxxxxxxxxxxxx
> >> Cc: KY Srinivasan; Haiyang Zhang; linux-kernel@xxxxxxxxxxxxxxx; Dexuan
> Cui;
> >> Ingo Molnar; Paul E. McKenney; Rafael J. Wysocki; Peter Zijlstra; Thomas
> >> Gleixner; Radim KrÄmÃÅ
> >> Subject: [PATCH v2 0/2] Drivers: hv: vmbus: use
> cpu_hotplug_enable/disable
> >> for CPU offlining prevention
> >>
> >> Changes since v1:
> >> - Make cpu_hotplug_disabled a counter [Radim KrÄmÃÅ]
> >>
> >> Export cpu_hotplug_enable/cpu_hotplug_disable functions from cpu.c
> and
> >> use
> >> them instead of altering smp_ops.cpu_disable in Hyper-V vmbus module.
> >>
> >> Vitaly Kuznetsov (2):
> >> cpu-hotplug: export cpu_hotplug_enable/cpu_hotplug_disable
> >> Drivers: hv: vmbus: use cpu_hotplug_enable/disable
> >
> > Vitaly,
> >
> > Since there is a cross tree dependency here, could you resubmit the vmbus
> patch
> > after the CPU hotplug patch has been committed.
>
> I'm afraid it won't be committed without the second patch as without a
> single user of cpu_hotplug_enable/cpu_hotplug_disable (among modules)
> this patch doesn't make much sense. I would rather expect both of them
> to go through Greg's tree but with proper sign-offs/reviewed-bys. And
> of course this decision is up to tree maintainers, I'll resubmit the
> vmbus patch in case CPU hotplug patch gets committed separately.

I had asked if Greg could take both the patches and I have not heard from him yet and I
assumed that he would not. This has happened to me before and I have done just that -
show the need by sending patches that would use the functionality and get them into
the tree in the correct order. Greg, please let us know how you want to handle this; I have a
bunch of patches that I am sitting not knowing how Vitaly's patches will be merged.

Regards,

K. Y
>
> Thanks,
>
> >
> > Regards,
> >
> > K. Y
> >>
> >> Documentation/power/suspend-and-cpuhotplug.txt | 6 ++--
> >> drivers/hv/vmbus_drv.c | 38 +++-----------------------
> >> kernel/cpu.c | 13 +++++----
> >> 3 files changed, 15 insertions(+), 42 deletions(-)
> >>
> >> --
> >> 1.9.3
>
> --
> Vitaly