linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: "Radim Krčmář" <rkrcmar@redhat.com>
To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org
Cc: Christoffer Dall <cdall@linaro.org>,
	Andrew Jones <drjones@redhat.com>,
	Marc Zyngier <marc.zyngier@arm.com>,
	Paolo Bonzini <pbonzini@redhat.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>
Subject: [PATCH v2 8/9] KVM: return if kvm_vcpu_wake_up() did wake up the VCPU
Date: Wed, 26 Apr 2017 22:32:26 +0200	[thread overview]
Message-ID: <20170426203227.12321-9-rkrcmar@redhat.com> (raw)
In-Reply-To: <20170426203227.12321-1-rkrcmar@redhat.com>

No need to kick a VCPU that we have just woken up.

Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
---
 include/linux/kvm_host.h |  2 +-
 virt/kvm/kvm_main.c      | 12 ++++++++----
 2 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 955debd82cf2..38cfe372918c 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -698,7 +698,7 @@ void kvm_vcpu_mark_page_dirty(struct kvm_vcpu *vcpu, gfn_t gfn);
 void kvm_vcpu_block(struct kvm_vcpu *vcpu);
 void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu);
 void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu);
-void kvm_vcpu_wake_up(struct kvm_vcpu *vcpu);
+bool kvm_vcpu_wake_up(struct kvm_vcpu *vcpu);
 void kvm_vcpu_kick(struct kvm_vcpu *vcpu);
 int kvm_vcpu_yield_to(struct kvm_vcpu *target);
 void kvm_vcpu_on_spin(struct kvm_vcpu *vcpu);
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 1efb07643035..632f7b3e198c 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -183,8 +183,8 @@ bool kvm_make_all_cpus_request(struct kvm *kvm, unsigned int req)
 		kvm_make_request(req, vcpu);
 		cpu = vcpu->cpu;
 
-		if (!(req & KVM_REQUEST_NO_WAKEUP))
-			kvm_vcpu_wake_up(vcpu);
+		if (!(req & KVM_REQUEST_NO_WAKEUP) && kvm_vcpu_wake_up(vcpu))
+			continue;
 
 		if (cpus != NULL && cpu != -1 && cpu != me &&
 		      kvm_vcpu_exiting_guest_mode(vcpu) != OUTSIDE_GUEST_MODE)
@@ -2195,7 +2195,7 @@ void kvm_vcpu_block(struct kvm_vcpu *vcpu)
 }
 EXPORT_SYMBOL_GPL(kvm_vcpu_block);
 
-void kvm_vcpu_wake_up(struct kvm_vcpu *vcpu)
+bool kvm_vcpu_wake_up(struct kvm_vcpu *vcpu)
 {
 	struct swait_queue_head *wqp;
 
@@ -2203,8 +2203,10 @@ void kvm_vcpu_wake_up(struct kvm_vcpu *vcpu)
 	if (swait_active(wqp)) {
 		swake_up(wqp);
 		++vcpu->stat.halt_wakeup;
+		return true;
 	}
 
+	return false;
 }
 EXPORT_SYMBOL_GPL(kvm_vcpu_wake_up);
 
@@ -2216,7 +2218,9 @@ void kvm_vcpu_kick(struct kvm_vcpu *vcpu)
 	int me;
 	int cpu = vcpu->cpu;
 
-	kvm_vcpu_wake_up(vcpu);
+	if (kvm_vcpu_wake_up(vcpu))
+		return;
+
 	me = get_cpu();
 	if (cpu != me && (unsigned)cpu < nr_cpu_ids && cpu_online(cpu))
 		if (kvm_arch_vcpu_should_kick(vcpu))
-- 
2.12.2

  parent reply	other threads:[~2017-04-26 20:33 UTC|newest]

Thread overview: 26+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-04-26 20:32 [PATCH v2 0/9] KVM: towards maintainable kvm_make_all_cpus_request() Radim Krčmář
2017-04-26 20:32 ` [PATCH v2 1/9] KVM: add kvm_{test,clear}_request to replace {test,clear}_bit Radim Krčmář
2017-04-27 11:33   ` Andrew Jones
2017-04-27 11:38   ` Cornelia Huck
2017-04-26 20:32 ` [PATCH v2 2/9] KVM: x86: always use kvm_make_request instead of set_bit Radim Krčmář
2017-04-27 11:33   ` Andrew Jones
2017-04-26 20:32 ` [PATCH v2 3/9] KVM: remove #ifndef CONFIG_S390 around kvm_vcpu_wake_up Radim Krčmář
2017-04-27 11:45   ` Cornelia Huck
2017-05-03 16:05   ` Radim Krčmář
2017-05-03 16:16   ` [PATCH v3] " Radim Krčmář
2017-05-03 17:04     ` Cornelia Huck
2017-04-26 20:32 ` [PATCH v2 4/9] KVM: mark requests that do not need a wakeup Radim Krčmář
2017-04-27 11:35   ` Andrew Jones
2017-04-27 12:00   ` Cornelia Huck
2017-04-26 20:32 ` [PATCH v2 5/9] KVM: perform a wake_up in kvm_make_all_cpus_request Radim Krčmář
2017-04-27 11:36   ` Andrew Jones
2017-04-27 12:06   ` Cornelia Huck
2017-04-27 12:15     ` Paolo Bonzini
2017-04-26 20:32 ` [PATCH v2 6/9] KVM: add explicit barrier to kvm_vcpu_kick Radim Krčmář
2017-04-26 20:32 ` [PATCH v2 7/9] KVM: improve arch vcpu request defining Radim Krčmář
2017-04-27 12:11   ` Cornelia Huck
2017-04-26 20:32 ` Radim Krčmář [this message]
2017-04-27 11:41   ` [PATCH v2 8/9] KVM: return if kvm_vcpu_wake_up() did wake up the VCPU Andrew Jones
2017-04-26 20:32 ` [PATCH v2 9/9] KVM: mark requests that need synchronization Radim Krčmář
2017-04-27 11:55   ` Andrew Jones
2017-04-27 12:36   ` Paolo Bonzini

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20170426203227.12321-9-rkrcmar@redhat.com \
    --to=rkrcmar@redhat.com \
    --cc=borntraeger@de.ibm.com \
    --cc=cdall@linaro.org \
    --cc=cornelia.huck@de.ibm.com \
    --cc=drjones@redhat.com \
    --cc=james.hogan@imgtec.com \
    --cc=kvm@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=marc.zyngier@arm.com \
    --cc=paulus@ozlabs.org \
    --cc=pbonzini@redhat.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).