[PATCH 1/4] KVM: Introduce kvm_make_all_cpus_request_except()

From: Suravee Suthikulpanit
Date: Wed May 06 2020 - 09:18:26 EST


This allows making request to all other vcpus except the one
specified in the parameter.

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@xxxxxxx>
---
arch/x86/kvm/hyperv.c | 2 +-
arch/x86/kvm/x86.c | 2 +-
include/linux/kvm_host.h | 3 +++
virt/kvm/kvm_main.c | 14 +++++++++++---
4 files changed, 16 insertions(+), 5 deletions(-)

diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
index bcefa9d..54d4b98 100644
--- a/arch/x86/kvm/hyperv.c
+++ b/arch/x86/kvm/hyperv.c
@@ -1427,7 +1427,7 @@ static u64 kvm_hv_flush_tlb(struct kvm_vcpu *current_vcpu, u64 ingpa,
*/
kvm_make_vcpus_request_mask(kvm,
KVM_REQ_TLB_FLUSH | KVM_REQUEST_NO_WAKEUP,
- vcpu_mask, &hv_vcpu->tlb_flush);
+ NULL, vcpu_mask, &hv_vcpu->tlb_flush);

ret_success:
/* We always do full TLB flush, set rep_done = rep_cnt. */
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 7900ea8..df473f9 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -8055,7 +8055,7 @@ void kvm_make_scan_ioapic_request_mask(struct kvm *kvm,
zalloc_cpumask_var(&cpus, GFP_ATOMIC);

kvm_make_vcpus_request_mask(kvm, KVM_REQ_SCAN_IOAPIC,
- vcpu_bitmap, cpus);
+ NULL, vcpu_bitmap, cpus);

free_cpumask_var(cpus);
}
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 01276e3..131cc15 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -813,8 +813,11 @@ int kvm_vcpu_write_guest(struct kvm_vcpu *vcpu, gpa_t gpa, const void *data,
void kvm_reload_remote_mmus(struct kvm *kvm);

bool kvm_make_vcpus_request_mask(struct kvm *kvm, unsigned int req,
+ struct kvm_vcpu *except,
unsigned long *vcpu_bitmap, cpumask_var_t tmp);
bool kvm_make_all_cpus_request(struct kvm *kvm, unsigned int req);
+bool kvm_make_all_cpus_request_except(struct kvm *kvm, unsigned int req,
+ struct kvm_vcpu *except);
bool kvm_make_cpus_request_mask(struct kvm *kvm, unsigned int req,
unsigned long *vcpu_bitmap);

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 74bdb7b..df73605 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -259,6 +259,7 @@ static inline bool kvm_kick_many_cpus(const struct cpumask *cpus, bool wait)
}

bool kvm_make_vcpus_request_mask(struct kvm *kvm, unsigned int req,
+ struct kvm_vcpu *except,
unsigned long *vcpu_bitmap, cpumask_var_t tmp)
{
int i, cpu, me;
@@ -268,7 +269,8 @@ bool kvm_make_vcpus_request_mask(struct kvm *kvm, unsigned int req,
me = get_cpu();

kvm_for_each_vcpu(i, vcpu, kvm) {
- if (vcpu_bitmap && !test_bit(i, vcpu_bitmap))
+ if ((vcpu_bitmap && !test_bit(i, vcpu_bitmap)) ||
+ (vcpu == except))
continue;

kvm_make_request(req, vcpu);
@@ -288,19 +290,25 @@ bool kvm_make_vcpus_request_mask(struct kvm *kvm, unsigned int req,
return called;
}

-bool kvm_make_all_cpus_request(struct kvm *kvm, unsigned int req)
+bool kvm_make_all_cpus_request_except(struct kvm *kvm, unsigned int req,
+ struct kvm_vcpu *except)
{
cpumask_var_t cpus;
bool called;

zalloc_cpumask_var(&cpus, GFP_ATOMIC);

- called = kvm_make_vcpus_request_mask(kvm, req, NULL, cpus);
+ called = kvm_make_vcpus_request_mask(kvm, req, except, NULL, cpus);

free_cpumask_var(cpus);
return called;
}

+bool kvm_make_all_cpus_request(struct kvm *kvm, unsigned int req)
+{
+ return kvm_make_all_cpus_request_except(kvm, req, NULL);
+}
+
#ifndef CONFIG_HAVE_KVM_ARCH_TLB_FLUSH_ALL
void kvm_flush_remote_tlbs(struct kvm *kvm)
{
--
1.8.3.1