From: Viktor Mihajlovski <mihajlov@linux.vnet.ibm.com>
Date: Tue, 6 Feb 2018 10:18:56 +0000 (+0100)
Subject: qemu: Limit refresh of CPU halted state to s390
X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=818a29e0c7d6840e87e9ca6019b9f0bc1983566e;p=libvirt.git

qemu: Limit refresh of CPU halted state to s390

Refreshing the halted state can cause VM performance issues. Since
s390 is currently the only architecture with a known interest in
the halted state, we're avoiding to call QEMU on other platforms.

Signed-off-by: Viktor Mihajlovski <mihajlov@linux.vnet.ibm.com>
---

diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c
index 5395cd093c..aa652959ed 100644
--- a/src/qemu/qemu_domain.c
+++ b/src/qemu/qemu_domain.c
@@ -8726,6 +8726,11 @@ qemuDomainRefreshVcpuHalted(virQEMUDriverPtr driver,
     if (vm->def->virtType == VIR_DOMAIN_VIRT_QEMU)
         return 0;
 
+    /* The halted state is interresting only on s390(x). On other platforms
+     * the data would be stale at the time when it would be used. */
+    if (!ARCH_IS_S390(vm->def->os.arch))
+        return 0;
+
     if (qemuDomainObjEnterMonitorAsync(driver, vm, asyncJob) < 0)
         return -1;