[GIT PULL 0/2] KVM: s390: Fixes for 5.2-rc2

[GIT PULL 0/2] KVM: s390: Fixes for 5.2-rc2

[Christian Borntraeger]

Paolo, Radim,

two small changes for rc2 via kvm/master. One is a fix for typo that
was merged during this merge window, the other is a CPU consumption 
improvement for halt polling on s390.

The following changes since commit a188339ca5a396acc588e5851ed7e19f66b0ebd9:

  Linux 5.2-rc1 (2019-05-19 15:47:09 -0700)

are available in the Git repository at:

  git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux.git  tags/kvm-s390-master-5.2-1

for you to fetch changes up to 6e9b622d1c3628fae65217465a148b157a361c2a:

  KVM: s390: change default halt poll time to 50us (2019-05-20 09:40:39 +0200)

----------------------------------------------------------------
KVM: s390: Fixes for s390

- Fix typo in module paramter description
- Change default poll timer to improve cpu consumption

----------------------------------------------------------------
Christian Borntraeger (1):
      KVM: s390: change default halt poll time to 50us

Wei Yongjun (1):
      KVM: s390: fix typo in parameter description

 arch/s390/include/asm/kvm_host.h | 2 +-
 arch/s390/kvm/kvm-s390.c         | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

[GIT PULL 1/2] KVM: s390: fix typo in parameter description

[Christian Borntraeger]

From: Wei Yongjun <weiyongjun1@huawei.com>

Fix typo in parameter description.

Fixes: 8b905d28ee17 ("KVM: s390: provide kvm_arch_no_poll function")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Message-Id: <20190504065145.53665-1-weiyongjun1@huawei.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
 arch/s390/kvm/kvm-s390.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 8d6d75db8de6..ac6163c334d6 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -181,7 +181,7 @@ MODULE_PARM_DESC(hpage, "1m huge page backing support");
 /* maximum percentage of steal time for polling.  >100 is treated like 100 */
 static u8 halt_poll_max_steal = 10;
 module_param(halt_poll_max_steal, byte, 0644);
-MODULE_PARM_DESC(hpage, "Maximum percentage of steal time to allow polling");
+MODULE_PARM_DESC(halt_poll_max_steal, "Maximum percentage of steal time to allow polling");
 
 /*
  * For now we handle at most 16 double words as this is what the s390 base
-- 
2.21.0

[GIT PULL 2/2] KVM: s390: change default halt poll time to 50us

[Christian Borntraeger]

Recent measurements indicate that using 50us results in a reduced CPU
consumption, while still providing the benefit of halt polling. Let's
use 50us instead.

Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Janosch Frank <frankja@linux.ibm.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
 arch/s390/include/asm/kvm_host.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h
index bdbc81b5bc91..2b00a3ebee08 100644
--- a/arch/s390/include/asm/kvm_host.h
+++ b/arch/s390/include/asm/kvm_host.h
@@ -36,7 +36,7 @@
  */
 #define KVM_NR_IRQCHIPS 1
 #define KVM_IRQCHIP_NUM_PINS 4096
-#define KVM_HALT_POLL_NS_DEFAULT 80000
+#define KVM_HALT_POLL_NS_DEFAULT 50000
 
 /* s390-specific vcpu->requests bit members */
 #define KVM_REQ_ENABLE_IBS	KVM_ARCH_REQ(0)
-- 
2.21.0

Re: [GIT PULL 0/2] KVM: s390: Fixes for 5.2-rc2

[Paolo Bonzini]

On 20/05/19 12:30, Christian Borntraeger wrote:
>   git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux.git  tags/kvm-s390-master-5.2-1

Pulled, thanks.

Paolo