Re: [libvirt] [PATCH] qemuDomainNamespaceTeardownHostdev: Drop useless check

On Fri, Sep 07, 2018 at 07:21:18AM +0200, Michal Prívozník wrote: > On 09/07/2018 12:52 AM, John Ferlan wrote: >> >> >> On 09/06/2018 12:16 PM, Michal Privoznik wrote: >>> There is no need to check if @npaths is not zero. Let's >>> qemuDomainNamespaceUnlinkPaths() handle that. >>> >>> Signed-off-by: Michal Privoznik <mprivozn(a)redhat.com&gt; >>> --- >>>  src/qemu/qemu_domain.c | 3 +-- >>>  1 file changed, 1 insertion(+), 2 deletions(-) >>> >> >> At the cost of a possible unnecessary, but perhaps expensive call to >> qemuDomainGetPreservedMounts when npaths == 0? > Yes, this was exactly my reasoning when I touched this > Sure. But at least with my patch we are consistent. If it really bothers > us, we can have a check at the beginning of > qemuDomainNamespaceMknodPaths() and qemuDomainNamespaceUnlinkPaths(), > right after namespace check to return early if npaths is zero. > >> >> I think if you add a "filter" of npaths == 0, then return 0 in >> qemuDomainNamespaceUnlinkPaths, then that'd be a good thing... >> > > Okay. > >> >> Reviewed-by: John Ferlan <jferlan(a)redhat.com&gt; >> >> John >> >> I also wonder if the : >> >>     if (!qemuDomainNamespaceEnabled(vm, QEMU_DOMAIN_NS_MOUNT)) >>         return 0; >> >> that's "duplicated" in qemuDomainNamespaceTeardownHostdev and >> qemuDomainNamespaceUnlinkPaths could be "reworked"... >> > > Oh sure it could. We have two sets of functions apparently: one does the > check themselves and return early (e.g. qemuDomainNamespaceSetupDisk()) > and the other leave it to qemuDomainNamespaceMknodPaths() to return > return early (e.g. qemuDomainNamespaceSetupMemory()). and I left the early check in some places for the same reason. (For other places, it might've been just an oversight)