Commit e513229b4c38 ("Drivers: hv: vmbus: prevent cpu offlining on newer
hypervisors") was altering smp_ops.cpu_disable to prevent CPU offlining.
We can bo better by using cpu_hotplug_enable/disable functions instead of
such hard-coding.
Reported-by: Radim Krčmář <rkrcmar@xxxxxxxxxx>
Signed-off-by: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>
Signed-off-by: K. Y. Srinivasan <kys@xxxxxxxxxxxxx>
---
drivers/hv/vmbus_drv.c | 38 ++++----------------------------------
1 file changed, 4 insertions(+), 34 deletions(-)
diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
index cf20400..6de65fb 100644
--- a/drivers/hv/vmbus_drv.c
+++ b/drivers/hv/vmbus_drv.c
@@ -763,38 +763,6 @@ static void vmbus_isr(void)
}
}
-#ifdef CONFIG_HOTPLUG_CPU
-static int hyperv_cpu_disable(void)
-{
- return -ENOSYS;
-}
-
-static void hv_cpu_hotplug_quirk(bool vmbus_loaded)
-{
- static void *previous_cpu_disable;
-
- /*
- * Offlining a CPU when running on newer hypervisors (WS2012R2, Win8,
- * ...) is not supported at this moment as channel interrupts are
- * distributed across all of them.
- */
-
- if ((vmbus_proto_version == VERSION_WS2008) ||
- (vmbus_proto_version == VERSION_WIN7))
- return;
-
- if (vmbus_loaded) {
- previous_cpu_disable = smp_ops.cpu_disable;
- smp_ops.cpu_disable = hyperv_cpu_disable;
- pr_notice("CPU offlining is not supported by hypervisor\n");
- } else if (previous_cpu_disable)
- smp_ops.cpu_disable = previous_cpu_disable;
-}
-#else
-static void hv_cpu_hotplug_quirk(bool vmbus_loaded)
-{
-}
-#endif
/*
* vmbus_bus_init -Main vmbus driver initialization routine.
@@ -836,7 +804,8 @@ static int vmbus_bus_init(int irq)
if (ret)
goto err_alloc;
- hv_cpu_hotplug_quirk(true);
+ if (vmbus_proto_version > VERSION_WIN7)
+ cpu_hotplug_disable();
/*
* Only register if the crash MSRs are available
@@ -1121,7 +1090,8 @@ static void __exit vmbus_exit(void)
smp_call_function_single(cpu, hv_synic_cleanup, NULL, 1);
}
acpi_bus_unregister_driver(&vmbus_acpi_driver);
- hv_cpu_hotplug_quirk(false);
+ if (vmbus_proto_version > VERSION_WIN7)
+ cpu_hotplug_enable();
}
--
2.4.3
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