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

[Suravee Suthikulpanit <suravee.suthikulpanit@xxxxxxx>]

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