On Wed, Mar 27, 2024 at 4:07 PM Xuan Zhuo <xuanz...@linux.alibaba.com> wrote: > > On Wed, 27 Mar 2024 15:50:17 +0800, Jason Wang <jasow...@redhat.com> wrote: > > On Wed, Mar 27, 2024 at 3:16 PM Xuan Zhuo <xuanz...@linux.alibaba.com> > > wrote: > > > > > > On Tue, 26 Mar 2024 14:35:21 +0800, Jason Wang <jasow...@redhat.com> > > > wrote: > > > > On Mon, Mar 25, 2024 at 4:54 PM Xuan Zhuo <xuanz...@linux.alibaba.com> > > > > wrote: > > > > > > > > > > As discussed: > > > > > > > > > > http://lore.kernel.org/all/cacgkmevq0no8qgc46u4mgsmtud44fd_cflcpavmj3rhyqrz...@mail.gmail.com > > > > > > > > > > If the virtio is premapped mode, the driver should manage the dma > > > > > info by self. > > > > > So the virtio core should not store the dma info. We can release the > > > > > memory used > > > > > to store the dma info. > > > > > > > > > > For virtio-net xmit queue, if the virtio-net maintains the dma info, > > > > > the virtio-net must allocate too much memory(19 * queue_size for > > > > > per-queue), so > > > > > we do not plan to make the virtio-net to maintain the dma info by > > > > > default. The > > > > > virtio-net xmit queue only maintain the dma info when premapped mode > > > > > is enable > > > > > (such as AF_XDP is enable). > > > > > > > > > > So this patch set try to do: > > > > > > > > > > 1. make the virtio core to do not store the dma info when driver can > > > > > do that > > > > > - But if the desc_extra has not dma info, we face a new question, > > > > > it is hard to get the dma info of the desc with indirect flag. > > > > > For split mode, that is easy from desc, but for the packed mode, > > > > > it is hard to get the dma info from the desc. And hardening > > > > > the dma unmap is safe, we should store the dma info of indirect > > > > > descs when the virtio core does not store the bufer dma info. > > > > > > > > > > The follow patches to this: > > > > > * virtio_ring: packed: structure the indirect desc table > > > > > * virtio_ring: split: structure the indirect desc table > > > > > > > > > > - On the other side, in the umap handle, we mix the indirect > > > > > descs with > > > > > other descs. That make things too complex. I found if we we > > > > > distinguish > > > > > the descs with VRING_DESC_F_INDIRECT before unmap, thing will > > > > > be clearer. > > > > > > > > > > The follow patches do this. > > > > > * virtio_ring: packed: remove double check of the unmap ops > > > > > * virtio_ring: split: structure the indirect desc table > > > > > > > > > > 2. make the virtio core to enable premapped mode by find_vqs() params > > > > > - Because the find_vqs() will try to allocate memory for the dma > > > > > info. > > > > > If we set the premapped mode after find_vqs() and release the > > > > > dma info, that is odd. > > > > > > > > > > > > > > > Please review. > > > > > > > > > > Thanks > > > > > > > > This doesn't apply cleany on vhost.git linux-next branch. > > > > > > > > Which tree is this based on? > > > > > > > > > Sorry. That is on the top of "[PATCH vhost v5 0/6] refactor the params of > > > find_vqs()". > > > > > > Lore-URL: > > > http://lore.kernel.org/all/20240325090419.33677-1-xuanz...@linux.alibaba.com > > > > > > Thanks. > > > > I've tried that but it doesn't work: > > > > % git am ~/Downloads/\[PATCH\ vhost\ v5\ 01_10\]\ virtio_ring_\ > > introduce\ vring_need_unmap_buffer.eml > > Applying: virtio_ring: introduce vring_need_unmap_buffer > > error: patch failed: drivers/virtio/virtio_ring.c:2080 > > error: drivers/virtio/virtio_ring.c: patch does not apply > > Patch failed at 0001 virtio_ring: introduce vring_need_unmap_buffer > > hint: Use 'git am --show-current-patch=diff' to see the failed patch > > When you have resolved this problem, run "git am --continue". > > If you prefer to skip this patch, run "git am --skip" instead. > > To restore the original branch and stop patching, run "git am --abort". > > > > I'm using vhost.git linux-next branch, HEAD is > > > > commit 56e71885b0349241c07631a7b979b61e81afab6a > > Author: Maxime Coquelin <maxime.coque...@redhat.com> > > Date: Tue Jan 9 12:10:24 2024 +0100 > > > > vduse: Temporarily fail if control queue feature requested > > > NOT ON the vhost directly. > > That is on the top of "refactor the params of find_vqs"
I meant I just did it on top of this series. > > "refactor the params of find_vqs" said: > > """ > This pathset is splited from the > > > http://lore.kernel.org/all/20240229072044.77388-1-xuanz...@linux.alibaba.com > > That may needs some cycles to discuss. But that notifies too many > people. > """ > > But now that is broken due to the change of the that patch set. > > I will post the new version of these two patch set soon. Ok. Thanks > > Thanks. > > > > > > Thanks > > > > > > > > > > > > > Thanks > > > > > > > > > >
