From: "Radim Krčmář" <rkrcmar@redhat.com>
To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org
Cc: Paolo Bonzini <pbonzini@redhat.com>,
Andrew Jones <drjones@redhat.com>,
Marc Zyngier <marc.zyngier@arm.com>,
Christian Borntraeger <borntraeger@de.ibm.com>,
Cornelia Huck <cornelia.huck@de.ibm.com>,
James Hogan <james.hogan@imgtec.com>,
Paul Mackerras <paulus@ozlabs.org>,
Christoffer Dall <christoffer.dall@linaro.org>
Subject: [PATCH 3/5] KVM: optimize kvm_make_all_cpus_request
Date: Thu, 16 Feb 2017 17:04:47 +0100 [thread overview]
Message-ID: <20170216160449.13094-4-rkrcmar@redhat.com> (raw)
In-Reply-To: <20170216160449.13094-1-rkrcmar@redhat.com>
Use __kvm_request_set to avoid repeated use of wmb().
kvm_make_all_cpus_request is also a candidate for renaming.
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
---
virt/kvm/kvm_main.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 934f135c0d23..2250920ec965 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -177,8 +177,12 @@ bool kvm_make_all_cpus_request(struct kvm *kvm, unsigned int req)
zalloc_cpumask_var(&cpus, GFP_ATOMIC);
me = get_cpu();
+
+ /* Paired with the smp_mb__after_atomic in kvm_request_test_and_clear. */
+ smp_wmb();
+
kvm_for_each_vcpu(i, vcpu, kvm) {
- kvm_request_set(req, vcpu);
+ __kvm_request_set(req, vcpu);
cpu = vcpu->cpu;
/* Set ->requests bit before we read ->mode. */
--
2.11.1
next prev parent reply other threads:[~2017-02-16 16:06 UTC|newest]
Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-02-16 16:04 [PATCH 0/5] KVM: rename and extend vcpu->requests API Radim Krčmář
2017-02-16 16:04 ` [PATCH 1/5] KVM: change API for requests to match bit operations Radim Krčmář
2017-02-17 9:30 ` Cornelia Huck
2017-02-17 9:49 ` Andrew Jones
2017-02-17 9:52 ` Cornelia Huck
2017-02-17 15:01 ` Radim Krčmář
2017-02-16 16:04 ` [PATCH 2/5] KVM: add KVM request variants without barrier Radim Krčmář
2017-02-23 10:57 ` Paolo Bonzini
2017-02-23 15:50 ` Radim Krčmář
2017-02-16 16:04 ` Radim Krčmář [this message]
2017-02-16 16:04 ` [PATCH 4/5] KVM: add __kvm_request_needs_mb Radim Krčmář
2017-02-16 19:49 ` David Hildenbrand
2017-02-16 21:31 ` Radim Krčmář
2017-02-17 8:46 ` Christian Borntraeger
2017-02-17 10:13 ` David Hildenbrand
2017-02-17 10:19 ` Christian Borntraeger
2017-02-17 11:28 ` Christian Borntraeger
2017-02-22 15:17 ` Radim Krčmář
2017-02-22 19:23 ` Christian Borntraeger
2017-02-23 15:43 ` Radim Krčmář
2017-02-22 19:57 ` Christian Borntraeger
2017-02-23 10:20 ` David Hildenbrand
2017-02-23 15:39 ` Radim Krčmář
2017-02-24 11:34 ` Christoffer Dall
2017-02-24 12:46 ` Andrew Jones
2017-02-23 11:01 ` Paolo Bonzini
2017-02-23 15:52 ` Radim Krčmář
2017-02-16 16:04 ` [PATCH 5/5] KVM: add kvm_request_pending Radim Krčmář
2017-02-16 19:50 ` David Hildenbrand
2017-02-17 9:51 ` Andrew Jones
2017-02-17 14:59 ` Radim Krčmář
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