Re: [libvirt] [PATCH] cpu: break out when a right cpuCandidate found
On Thu, Feb 13, 2014 at 07:44:20AM +0000, Wangyufei (James) wrote:
>From 8123c5d64f940fa0fb0de32fc5e68035980b6b01 Mon Sep 17 00:00:00
2001
From: WangYufei <james.wangyufei(a)huawei.com>
Date: Thu, 13 Feb 2014 07:17:11 +0000
Subject: [PATCH] cpu: break out when a right cpuCandidate found
In function x86Decode there's a code segment in while cycle like this:
if (cpuModel == NULL
|| cpuModel->nfeatures > cpuCandidate->nfeatures) {
virCPUDefFree(cpuModel);
cpuModel = cpuCandidate;
cpuData = candidate->data;
} else {
virCPUDefFree(cpuCandidate);
}
when it finds the right cpuCandidate, it doesn't break out the cycle, but continues
run in it, and cpuModel will never get a new value, it's meaningless. It should
break out when a right cpuCndidate found.
Inside this condition, the code doesn't always choose the perfect
candidate. You don't consider a situation when the cycle continues
and the next candidate model is the preferred one, thus satisfies
previous condition, which looks like this:
if (preferred && STREQ(cpuCandidate->model, preferred)) {
virCPUDefFree(cpuModel);
cpuModel = cpuCandidate;
cpuData = candidate->data;
break;
}
Where the "perfect" cpuModel is found, used and the condition breaks
(appropriately this time). But I could also misunderstood the code.
Martin
Attachments:
- signature.asc (application/pgp-signature — 836 bytes)