Re: [PULL v2 0/5] 9p queue (previous 2020-10-15)

From: Christian Schoenebeck <qemu_oss@crudebyte.com>
To: qemu-devel@nongnu.org
Cc: Peter Maydell <peter.maydell@linaro.org>, Greg Kurz <groug@kaod.org>
Subject: Re: [PULL v2 0/5] 9p queue (previous 2020-10-15)
Date: Mon, 19 Oct 2020 12:27:21 +0200	[thread overview]
Message-ID: <3471677.uDMLW391hT@silver> (raw)
In-Reply-To: <CAFEAcA_1AcW9n949HXtX6QOmYvTRLcMb_PXLtKSG77s=zdzkwg@mail.gmail.com>

On Montag, 19. Oktober 2020 12:22:47 CEST Peter Maydell wrote:
> On Mon, 19 Oct 2020 at 11:19, Christian Schoenebeck
> 
> <qemu_oss@crudebyte.com> wrote:
> > On Montag, 19. Oktober 2020 11:52:38 CEST Peter Maydell wrote:
> > > This emits a lot of new warnings during 'make check':
> > > 
> > > PASS 27 qtest-arm: qos-test
> > > /arm/virt/virtio-mmio/virtio-bus/virtio-9p-device/virtio-9p/virtio-9p-te
> > > sts/ local/config qemu-system-arm: warning: 9p: degraded performance: a
> > > reasonable high msize should be chosen on client/guest side (chosen
> > > msize is <= 8192). See
> > > https://wiki.qemu.org/Documentation/9psetup#msize for details. PASS 28
> > > qtest-arm: qos-test
> > > /arm/virt/virtio-mmio/virtio-bus/virtio-9p-device/virtio-9p/virtio-9p-te
> > > sts/ local/create_dir
> > > 
> > > PASS 54 qtest-i386: qos-test
> > > /i386/pc/i440FX-pcihost/pci-bus-pc/pci-bus/virtio-9p-pci/virtio-9p/virti
> > > o-9p -tests/local/config qemu-system-i386: warning: 9p: degraded
> > > performance: a reasonable high msize should be chosen on client/guest
> > > side (chosen msize is <= 8192). See
> > > https://wiki.qemu.org/Documentation/9psetup#msize for details. PASS 55
> > > qtest-i386: qos-test
> > > /i386/pc/i440FX-pcihost/pci-bus-pc/pci-bus/virtio-9p-pci/virtio-9p/virti
> > > o-9p -tests/local/create_dir
> > 
> > One warning per test suite run (i.e. per architecture due to
> > warn_report_once()), yes. That performance warning is meant for end user
> > installations to remind them setting some (reasonable high) value for 9p
> > client parameter 'msize' on guest OS side. The warning triggers here
> > because the 9p test cases intentionally run with a small 'msize' to guard
> > edge cases.
> > 
> > Would it be Ok for you to merge it with this performance warning for now?
> > I
> > can take care of silencing it before 5.2 release. It probably requires to
> > introduce a new CL option to suppress performance warnings like these, or
> > by finding a way to detect that we're currently just running qtests.
> 
> The usual approach is to suppress this kind of warning by guarding
> it with if (qtest_enabled()) { ... }.

Ah, didn't see that one. I do that and resend, thanks!

Best regards,
Christian Schoenebeck