public inbox for linux-s390@vger.kernel.org
 help / color / mirror / Atom feed
From: Christian Borntraeger <borntraeger@de.ibm.com>
To: "Paolo Bonzini" <pbonzini@redhat.com>,
	"Radim Krčmář" <rkrcmar@redhat.com>
Cc: KVM <kvm@vger.kernel.org>, Cornelia Huck <cohuck@redhat.com>,
	Christian Borntraeger <borntraeger@de.ibm.com>,
	linux-s390 <linux-s390@vger.kernel.org>,
	Janosch Frank <frankja@linux.vnet.ibm.com>
Subject: [GIT PULL 4/6] KVM: s390: drop use of spin lock in __floating_irq_kick
Date: Tue, 16 Jan 2018 16:03:12 +0100	[thread overview]
Message-ID: <20180116150314.201352-5-borntraeger@de.ibm.com> (raw)
In-Reply-To: <20180116150314.201352-1-borntraeger@de.ibm.com>

From: Michael Mueller <mimu@linux.vnet.ibm.com>

It is not required to take to a lock to protect access to the cpuflags
of the local interrupt structure of a vcpu as the performed operation
is an atomic_or.

Signed-off-by: Michael Mueller <mimu@linux.vnet.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
 arch/s390/kvm/interrupt.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/arch/s390/kvm/interrupt.c b/arch/s390/kvm/interrupt.c
index 024ad8bcc516..818aa4248b0f 100644
--- a/arch/s390/kvm/interrupt.c
+++ b/arch/s390/kvm/interrupt.c
@@ -1569,7 +1569,6 @@ static void __floating_irq_kick(struct kvm *kvm, u64 type)
 
 	/* make the VCPU drop out of the SIE, or wake it up if sleeping */
 	li = &dst_vcpu->arch.local_int;
-	spin_lock(&li->lock);
 	switch (type) {
 	case KVM_S390_MCHK:
 		atomic_or(CPUSTAT_STOP_INT, li->cpuflags);
@@ -1581,7 +1580,6 @@ static void __floating_irq_kick(struct kvm *kvm, u64 type)
 		atomic_or(CPUSTAT_EXT_INT, li->cpuflags);
 		break;
 	}
-	spin_unlock(&li->lock);
 	kvm_s390_vcpu_wakeup(dst_vcpu);
 }
 
-- 
2.13.4

  parent reply	other threads:[~2018-01-16 15:03 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-01-16 15:03 [GIT PULL 0/6] KVM: s390: Fixes and features for 4.16 Christian Borntraeger
2018-01-16 15:03 ` [GIT PULL 1/6] s390x/mm: cleanup gmap_pte_op_walk() Christian Borntraeger
2018-01-16 15:03 ` [GIT PULL 2/6] KVM: s390: use created_vcpus in more places Christian Borntraeger
2018-01-16 15:03 ` [GIT PULL 3/6] KVM: s390: add debug tracing for cpu features of CPU model Christian Borntraeger
2018-01-16 15:03 ` Christian Borntraeger [this message]
2018-01-16 15:03 ` [GIT PULL 5/6] kvm_config: add CONFIG_S390_GUEST Christian Borntraeger
2018-01-16 15:03 ` [GIT PULL 6/6] KVM: s390: cleanup struct kvm_s390_float_interrupt Christian Borntraeger
2018-01-16 15:09 ` [GIT PULL 0/6] KVM: s390: Fixes and features for 4.16 Paolo Bonzini
2018-01-16 15:14   ` Christian Borntraeger
2018-01-16 15:27     ` Radim Krčmář
2018-01-16 15:35       ` 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=20180116150314.201352-5-borntraeger@de.ibm.com \
    --to=borntraeger@de.ibm.com \
    --cc=cohuck@redhat.com \
    --cc=frankja@linux.vnet.ibm.com \
    --cc=kvm@vger.kernel.org \
    --cc=linux-s390@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