linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Wanpeng Li <kernellwp@gmail.com>
To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org
Cc: "Paolo Bonzini" <pbonzini@redhat.com>,
	"Radim Krčmář" <rkrcmar@redhat.com>
Subject: [PATCH 1/3] KVM: Don't need to wakeup vCPU twice afer timer fire
Date: Wed, 31 Jul 2019 19:27:16 +0800	[thread overview]
Message-ID: <1564572438-15518-1-git-send-email-wanpengli@tencent.com> (raw)

From: Wanpeng Li <wanpengli@tencent.com>

kvm_set_pending_timer() will take care to wake up the sleeping vCPU which 
has pending timer, don't need to check this in apic_timer_expired() again.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
---
 arch/x86/kvm/lapic.c | 8 --------
 1 file changed, 8 deletions(-)

diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 0aa1586..685d17c 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -1548,7 +1548,6 @@ static void kvm_apic_inject_pending_timer_irqs(struct kvm_lapic *apic)
 static void apic_timer_expired(struct kvm_lapic *apic)
 {
 	struct kvm_vcpu *vcpu = apic->vcpu;
-	struct swait_queue_head *q = &vcpu->wq;
 	struct kvm_timer *ktimer = &apic->lapic_timer;
 
 	if (atomic_read(&apic->lapic_timer.pending))
@@ -1566,13 +1565,6 @@ static void apic_timer_expired(struct kvm_lapic *apic)
 
 	atomic_inc(&apic->lapic_timer.pending);
 	kvm_set_pending_timer(vcpu);
-
-	/*
-	 * For x86, the atomic_inc() is serialized, thus
-	 * using swait_active() is safe.
-	 */
-	if (swait_active(q))
-		swake_up_one(q);
 }
 
 static void start_sw_tscdeadline(struct kvm_lapic *apic)
-- 
2.7.4


             reply	other threads:[~2019-07-31 11:27 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-07-31 11:27 Wanpeng Li [this message]
2019-07-31 11:27 ` [PATCH 2/3] KVM: Check preempted_in_kernel for involuntary preemption Wanpeng Li
2019-07-31 11:27 ` [PATCH 3/3] KVM: Fix leak vCPU's VMCS value into other pCPU Wanpeng Li
2019-07-31 11:39   ` [PATCH v2 " Wanpeng Li
2019-07-31 12:55     ` Paolo Bonzini
2019-08-01  3:35       ` Wanpeng Li
2019-07-31 12:56 ` [PATCH 1/3] KVM: Don't need to wakeup vCPU twice afer timer fire Paolo Bonzini
2019-07-31 13:14   ` Vitaly Kuznetsov
2019-07-31 16:39     ` 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=1564572438-15518-1-git-send-email-wanpengli@tencent.com \
    --to=kernellwp@gmail.com \
    --cc=kvm@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=pbonzini@redhat.com \
    --cc=rkrcmar@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).