* Re: [PATCH] powerpc: use device_online/offline() instead of cpu_up/down()
2014-10-31 19:41 ` [PATCH] powerpc: use device_online/offline() instead of cpu_up/down() Dan Streetman
@ 2014-11-02 4:58 ` Bharata B Rao
2014-11-03 15:45 ` Nathan Fontenot
1 sibling, 0 replies; 3+ messages in thread
From: Bharata B Rao @ 2014-11-02 4:58 UTC (permalink / raw)
To: Dan Streetman
Cc: Thomas Falcon, Greg Kroah-Hartman, Rafael J. Wysocki,
Rafael J. Wysocki, linux-kernel, Paul Mackerras, Tyrel Datwyler,
Grant Likely, Nathan Fontenot, Andrew Morton, Neil Zhang,
linuxppc-dev, Daniel Walter
On Fri, Oct 31, 2014 at 03:41:34PM -0400, Dan Streetman wrote:
> In powerpc pseries platform dlpar operations, Use device_online() and
> device_offline() instead of cpu_up() and cpu_down().
>
> Calling cpu_up/down directly does not update the cpu device offline
> field, which is used to online/offline a cpu from sysfs. Calling
> device_online/offline instead keeps the sysfs cpu online value correct.
> The hotplug lock, which is required to be held when calling
> device_online/offline, is already held when dlpar_online/offline_cpu
> are called, since they are called only from cpu_probe|release_store.
>
> This patch fixes errors on PowerVM systems that have cpu(s) added/removed
> using dlpar operations; without this patch, the
> /sys/devices/system/cpu/cpuN/online nodes do not correctly show the
> online state of added/removed cpus.
Verified the patch to be working as expected when I online and offline
CPUs of a PowerKVM guest using QEMU (plus my RFC hotplug patchset for
QEMU)
Regards,
Bharata.
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [PATCH] powerpc: use device_online/offline() instead of cpu_up/down()
2014-10-31 19:41 ` [PATCH] powerpc: use device_online/offline() instead of cpu_up/down() Dan Streetman
2014-11-02 4:58 ` Bharata B Rao
@ 2014-11-03 15:45 ` Nathan Fontenot
1 sibling, 0 replies; 3+ messages in thread
From: Nathan Fontenot @ 2014-11-03 15:45 UTC (permalink / raw)
To: Dan Streetman, Benjamin Herrenschmidt, Michael Ellerman,
Tyrel Datwyler
Cc: Thomas Falcon, Greg Kroah-Hartman, Rafael J. Wysocki,
Rafael J. Wysocki, linux-kernel, Paul Mackerras, Daniel Walter,
Bharata B Rao, Grant Likely, Andrew Morton, Neil Zhang,
linuxppc-dev
On 10/31/2014 02:41 PM, Dan Streetman wrote:
> In powerpc pseries platform dlpar operations, Use device_online() and
> device_offline() instead of cpu_up() and cpu_down().
>
> Calling cpu_up/down directly does not update the cpu device offline
> field, which is used to online/offline a cpu from sysfs. Calling
> device_online/offline instead keeps the sysfs cpu online value correct.
> The hotplug lock, which is required to be held when calling
> device_online/offline, is already held when dlpar_online/offline_cpu
> are called, since they are called only from cpu_probe|release_store.
>
> This patch fixes errors on PowerVM systems that have cpu(s) added/removed
> using dlpar operations; without this patch, the
> /sys/devices/system/cpu/cpuN/online nodes do not correctly show the
> online state of added/removed cpus.
>
> Signed-off-by: Dan Streetman <ddstreet@ieee.org>
> Cc: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Acked-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
> ---
>
> Previous discussion for this:
> https://lkml.org/lkml/2014/10/29/839
>
> arch/powerpc/platforms/pseries/dlpar.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/arch/powerpc/platforms/pseries/dlpar.c b/arch/powerpc/platforms/pseries/dlpar.c
> index 6ad83bd..c22bb1b 100644
> --- a/arch/powerpc/platforms/pseries/dlpar.c
> +++ b/arch/powerpc/platforms/pseries/dlpar.c
> @@ -382,7 +382,7 @@ static int dlpar_online_cpu(struct device_node *dn)
> BUG_ON(get_cpu_current_state(cpu)
> != CPU_STATE_OFFLINE);
> cpu_maps_update_done();
> - rc = cpu_up(cpu);
> + rc = device_online(get_cpu_device(cpu));
> if (rc)
> goto out;
> cpu_maps_update_begin();
> @@ -467,7 +467,7 @@ static int dlpar_offline_cpu(struct device_node *dn)
> if (get_cpu_current_state(cpu) == CPU_STATE_ONLINE) {
> set_preferred_offline_state(cpu, CPU_STATE_OFFLINE);
> cpu_maps_update_done();
> - rc = cpu_down(cpu);
> + rc = device_offline(get_cpu_device(cpu));
> if (rc)
> goto out;
> cpu_maps_update_begin();
>
^ permalink raw reply [flat|nested] 3+ messages in thread