Mailing List Archive

[PATCH v2 4/5] x86/xen: Don't register Xen IPIs when they aren't going to be used
From: David Woodhouse <dwmw@amazon.co.uk>

In the case where xen_have_vector_callback is false, we still register
the IPI vectors in xen_smp_intr_init() for the secondary CPUs even
though they aren't going to be used. Stop doing that.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
---
arch/x86/xen/enlighten_hvm.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/xen/enlighten_hvm.c b/arch/x86/xen/enlighten_hvm.c
index a1c07e0c888e..7a6ef517e81a 100644
--- a/arch/x86/xen/enlighten_hvm.c
+++ b/arch/x86/xen/enlighten_hvm.c
@@ -164,10 +164,10 @@ static int xen_cpu_up_prepare_hvm(unsigned int cpu)
else
per_cpu(xen_vcpu_id, cpu) = cpu;
rc = xen_vcpu_setup(cpu);
- if (rc)
+ if (rc || !xen_have_vector_callback)
return rc;

- if (xen_have_vector_callback && xen_feature(XENFEAT_hvm_safe_pvclock))
+ if (xen_feature(XENFEAT_hvm_safe_pvclock))
xen_setup_timer(cpu);

rc = xen_smp_intr_init(cpu);
--
2.29.2
Re: [PATCH v2 4/5] x86/xen: Don't register Xen IPIs when they aren't going to be used [ In reply to ]
On 1/5/21 6:57 PM, David Woodhouse wrote:
> From: David Woodhouse <dwmw@amazon.co.uk>
>
> In the case where xen_have_vector_callback is false, we still register
> the IPI vectors in xen_smp_intr_init() for the secondary CPUs even
> though they aren't going to be used. Stop doing that.
>
> Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>



Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>