lkml.org 
[lkml]   [2022]   [Sep]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v5 15/30] KVM: Add arch hook for cpu offline event
Date
From: Isaku Yamahata <isaku.yamahata@intel.com>

Factor out the logic on cpu offline event as arch callback. Later kvm/x86
will override it.

Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
---
include/linux/kvm_host.h | 1 +
virt/kvm/kvm_main.c | 30 +++++++++++++++++++-----------
2 files changed, 20 insertions(+), 11 deletions(-)

diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 013b33a19030..f3a79d55ca8c 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -1435,6 +1435,7 @@ static inline void kvm_create_vcpu_debugfs(struct kvm_vcpu *vcpu) {}
#endif

int kvm_arch_online_cpu(unsigned int cpu, int usage_count);
+int kvm_arch_offline_cpu(unsigned int cpu, int usage_count);
int kvm_arch_reboot(int val);
int kvm_arch_suspend(int usage_count);
void kvm_arch_resume(int usage_count);
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 4c535ae412a7..ad9b8b7d21fa 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -1174,6 +1174,21 @@ int __weak kvm_arch_online_cpu(unsigned int cpu, int usage_count)
return ret;
}

+int __weak kvm_arch_offline_cpu(unsigned int cpu, int usage_count)
+{
+ if (usage_count) {
+ /*
+ * arch callback kvm_arch_hardware_disable() assumes that
+ * preemption is disabled for historical reason. Disable
+ * preemption until all arch callbacks are fixed.
+ */
+ preempt_disable();
+ hardware_disable_nolock(NULL);
+ preempt_enable();
+ }
+ return 0;
+}
+
int __weak kvm_arch_reboot(int val)
{
on_each_cpu(hardware_disable_nolock, NULL, 1);
@@ -5137,19 +5152,12 @@ static void hardware_disable_nolock(void *junk)

static int kvm_offline_cpu(unsigned int cpu)
{
+ int ret;
+
mutex_lock(&kvm_lock);
- if (kvm_usage_count) {
- /*
- * arch callback kvm_arch_hardware_disable() assumes that
- * preemption is disabled for historical reason. Disable
- * preemption until all arch callbacks are fixed.
- */
- preempt_disable();
- hardware_disable_nolock(NULL);
- preempt_enable();
- }
+ ret = kvm_arch_offline_cpu(cpu, kvm_usage_count);
mutex_unlock(&kvm_lock);
- return 0;
+ return ret;
}

static void kvm_del_vm(void)
--
2.25.1
\
 
 \ /
  Last update: 2022-09-22 20:26    [W:0.395 / U:2.260 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site