Message ID | 1519483453-12613-1-git-send-email-junjie.j.chen@intel.com (mailing list archive) |
---|---|
State | Superseded, archived |
Delegated to: | Maxime Coquelin |
Headers | show |
Context | Check | Description |
---|---|---|
ci/checkpatch | warning | coding style issues |
ci/Intel-compilation | success | Compilation OK |
Hi Junjie, > -----Original Message----- > From: Chen, Junjie J > Sent: Saturday, February 24, 2018 10:44 PM > To: yliu@fridaylinux.org; maxime.coquelin@redhat.com; Tan, Jianfeng > Cc: dev@dpdk.org; Chen, Junjie J > Subject: [PATCH] doc: add driver limitation for vhost dequeue zero copy > > In vhost-switch example, when binding nic to vfio-pci, dequeue zero > copy cannot work in VM2NIC mode due to no iommu dma mapping is setup > for guest memory currently. IMO, it's a limitation that can be fixed. Do you want to try fixing it? > > Signed-off-by: Junjie Chen <junjie.j.chen@intel.com> > --- > doc/guides/sample_app_ug/vhost.rst | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/doc/guides/sample_app_ug/vhost.rst > b/doc/guides/sample_app_ug/vhost.rst > index a4bdc6a..1591a31 100644 > --- a/doc/guides/sample_app_ug/vhost.rst > +++ b/doc/guides/sample_app_ug/vhost.rst Besides, we might also need to put such limitation at http://dpdk.org/doc/guides/prog_guide/vhost_lib.html Thanks, Jianfeng > @@ -147,7 +147,10 @@ retries on an RX burst, it takes effect only when rx > retry is enabled. The > default value is 15. > > **--dequeue-zero-copy** > -Dequeue zero copy will be enabled when this option is given. > +Dequeue zero copy will be enabled when this option is given, it is worth to > +note that if NIC is binded to vfio-pci driver, dequeue zero copy cannot work > +at VM2NIC mode (vm2vm=0) due to currently we don't setup iommu dma > mapping for > +guest memory. > > **--vlan-strip 0|1** > VLAN strip option is removed, because different NICs have different > behaviors > -- > 2.0.1
> > Signed-off-by: Junjie Chen <junjie.j.chen@intel.com> > > --- > > doc/guides/sample_app_ug/vhost.rst | 5 ++++- > > 1 file changed, 4 insertions(+), 1 deletion(-) > > > > diff --git a/doc/guides/sample_app_ug/vhost.rst > > b/doc/guides/sample_app_ug/vhost.rst > > index a4bdc6a..1591a31 100644 > > --- a/doc/guides/sample_app_ug/vhost.rst > > +++ b/doc/guides/sample_app_ug/vhost.rst Can you please supersede this patch and the V2 if you have sent a V3 to the mailing list. Thanks
Done, Thanks for reminder. Cheers JJ > -----Original Message----- > From: Kovacevic, Marko > Sent: Tuesday, March 13, 2018 5:13 PM > To: Tan, Jianfeng <jianfeng.tan@intel.com>; Chen, Junjie J > <junjie.j.chen@intel.com>; dev@dpdk.org > Cc: yliu@fridaylinux.org; maxime.coquelin@redhat.com > Subject: RE: [dpdk-dev] [PATCH] doc: add driver limitation for vhost dequeue > zero copy > > > > Signed-off-by: Junjie Chen <junjie.j.chen@intel.com> > > > --- > > > doc/guides/sample_app_ug/vhost.rst | 5 ++++- > > > 1 file changed, 4 insertions(+), 1 deletion(-) > > > > > > diff --git a/doc/guides/sample_app_ug/vhost.rst > > > b/doc/guides/sample_app_ug/vhost.rst > > > index a4bdc6a..1591a31 100644 > > > --- a/doc/guides/sample_app_ug/vhost.rst > > > +++ b/doc/guides/sample_app_ug/vhost.rst > > > Can you please supersede this patch and the V2 if you have sent a V3 to the > mailing list. > > Thanks
diff --git a/doc/guides/sample_app_ug/vhost.rst b/doc/guides/sample_app_ug/vhost.rst index a4bdc6a..1591a31 100644 --- a/doc/guides/sample_app_ug/vhost.rst +++ b/doc/guides/sample_app_ug/vhost.rst @@ -147,7 +147,10 @@ retries on an RX burst, it takes effect only when rx retry is enabled. The default value is 15. **--dequeue-zero-copy** -Dequeue zero copy will be enabled when this option is given. +Dequeue zero copy will be enabled when this option is given, it is worth to +note that if NIC is binded to vfio-pci driver, dequeue zero copy cannot work +at VM2NIC mode (vm2vm=0) due to currently we don't setup iommu dma mapping for +guest memory. **--vlan-strip 0|1** VLAN strip option is removed, because different NICs have different behaviors
In vhost-switch example, when binding nic to vfio-pci, dequeue zero copy cannot work in VM2NIC mode due to no iommu dma mapping is setup for guest memory currently. Signed-off-by: Junjie Chen <junjie.j.chen@intel.com> --- doc/guides/sample_app_ug/vhost.rst | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)