diff mbox series

[v4,10/10] powerpc/pseries: Honour current SMT state when DLPAR onlining CPUs

Message ID 20230705145143.40545-11-ldufour@linux.ibm.com
State New
Headers
Series Introduce SMT level and add PowerPC support |

Commit Message

Laurent Dufour July 5, 2023, 2:51 p.m. UTC 
  From: Michael Ellerman <mpe@ellerman.id.au>

Integrate with the generic SMT support, so that when a CPU is DLPAR
onlined it is brought up with the correct SMT mode.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
 arch/powerpc/platforms/pseries/hotplug-cpu.c | 8 ++++++++
 1 file changed, 8 insertions(+)

Comments

Srikar Dronamraju Aug. 14, 2023, 10:53 a.m. UTC | #1 
* Laurent Dufour <ldufour@linux.ibm.com> [2023-07-05 16:51:43]:

> From: Michael Ellerman <mpe@ellerman.id.au>
> 
> Integrate with the generic SMT support, so that when a CPU is DLPAR
> onlined it is brought up with the correct SMT mode.
> 

Looks good to me.

Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
> ---
>  arch/powerpc/platforms/pseries/hotplug-cpu.c | 8 ++++++++
>  1 file changed, 8 insertions(+)
>
diff mbox series

Patch

diff --git a/arch/powerpc/platforms/pseries/hotplug-cpu.c b/arch/powerpc/platforms/pseries/hotplug-cpu.c
index 61fb7cb00880..e62835a12d73 100644
--- a/arch/powerpc/platforms/pseries/hotplug-cpu.c
+++ b/arch/powerpc/platforms/pseries/hotplug-cpu.c
@@ -398,6 +398,14 @@  static int dlpar_online_cpu(struct device_node *dn)
 		for_each_present_cpu(cpu) {
 			if (get_hard_smp_processor_id(cpu) != thread)
 				continue;
+
+			if (!topology_is_primary_thread(cpu)) {
+				if (cpu_smt_control != CPU_SMT_ENABLED)
+					break;
+				if (!topology_smt_thread_allowed(cpu))
+					break;
+			}
+
 			cpu_maps_update_done();
 			find_and_update_cpu_nid(cpu);
 			rc = device_online(get_cpu_device(cpu));