similar to: [External] Re: [PATCH] virtio_ring: Suppress tx interrupt when napi_tx disable

On Fri, Mar 24, 2023 at 02:47:02PM +0800, Jason Wang wrote: > On Fri, Mar 24, 2023 at 2:42?PM Michael S. Tsirkin <mst at redhat.com> wrote: > > > > On Fri, Mar 24, 2023 at 02:32:40PM +0800, Jason Wang wrote: > > > On Fri, Mar 24, 2023 at 1:59?PM Michael S. Tsirkin <mst at redhat.com> wrote: > > > > > > > > On Fri, Mar 24, 2023 at

Hi Michael, Albert, Albert Huang wrote on Sat, Mar 25, 2023 at 06:56:33PM +0800: > in virtio_net, if we disable the napi_tx, when we triger a tx interrupt, > the vq->event_triggered will be set to true. It will no longer be set to > false. Unless we explicitly call virtqueue_enable_cb_delayed or > virtqueue_enable_cb_prepare. This patch (commited as 35395770f803

On Tue, Mar 21, 2023 at 5:00?PM Albert Huang <huangjie.albert at bytedance.com> wrote: > > From: "huangjie.albert" <huangjie.albert at bytedance.com> > > fix commit 8d622d21d248 ("virtio: fix up virtio_disable_cb") > > if we disable the napi_tx. when we triger a tx interrupt, the typo should be "trigger" > vq->event_triggered will

is the below same as what I posted or different? how? On Sat, Mar 25, 2023 at 06:56:33PM +0800, Albert Huang wrote: > in virtio_net, if we disable the napi_tx, when we triger a tx interrupt, > the vq->event_triggered will be set to true. It will no longer be set to > false. Unless we explicitly call virtqueue_enable_cb_delayed or > virtqueue_enable_cb_prepare. > > If we

virtio_disable_cb is currently a nop for split ring with event index. This is because it used to be always called from a callback when we know device won't trigger more events until we update the index. However, now that we run with interrupts enabled a lot we also poll without a callback so that is different: disabling callbacks will help reduce the number of spurious interrupts. Further, if

With the implementation of napi-tx in virtio driver, we clean tx descriptors from rx napi handler, for the purpose of reducing tx complete interrupts. But this introduces a race where tx complete interrupt has been raised, but the handler finds there is no work to do because we have done the work in the previous rx interrupt handler. A similar issue exists with polling from start_xmit, it is

With the implementation of napi-tx in virtio driver, we clean tx descriptors from rx napi handler, for the purpose of reducing tx complete interrupts. But this introduces a race where tx complete interrupt has been raised, but the handler finds there is no work to do because we have done the work in the previous rx interrupt handler. A similar issue exists with polling from start_xmit, it is

Hello everyone, This RFC implements packed ring support for virtio driver. The code was tested with DPDK vhost (testpmd/vhost-PMD) implemented by Jens at http://dpdk.org/ml/archives/dev/2018-January/089417.html Minor changes are needed for the vhost code, e.g. to kick the guest. TODO: - Refinements and bug fixes; - Split into small patches; - Test indirect descriptor support; - Test/fix event

Hello everyone, This RFC implements packed ring support for virtio driver. The code was tested with DPDK vhost (testpmd/vhost-PMD) implemented by Jens at http://dpdk.org/ml/archives/dev/2018-January/089417.html Minor changes are needed for the vhost code, e.g. to kick the guest. TODO: - Refinements and bug fixes; - Split into small patches; - Test indirect descriptor support; - Test/fix event

Hi, This patch set implements packed ring support in virtio driver. A performance test between pktgen (pktgen_sample03_burst_single_flow.sh) and DPDK vhost (testpmd/rxonly/vhost-PMD) has been done, I saw ~30% performance gain in packed ring in this case. To make this patch set work with below patch set for vhost, some hacks are needed to set the _F_NEXT flag in indirect descriptors (this should

Hi, This patch set implements packed ring support in virtio driver. A performance test between pktgen (pktgen_sample03_burst_single_flow.sh) and DPDK vhost (testpmd/rxonly/vhost-PMD) has been done, I saw ~30% performance gain in packed ring in this case. To make this patch set work with below patch set for vhost, some hacks are needed to set the _F_NEXT flag in indirect descriptors (this should

This is a follow up of the discussion in this thread: https://patchwork.ozlabs.org/patch/1001015/#2042353 Tiwei Bie (3): virtio_ring: define flags as shifts consistently virtio_ring: add VIRTIO_RING_NO_LEGACY virtio_ring: use new vring flags drivers/virtio/virtio_ring.c | 100 ++++++++++++++++++------------- include/uapi/linux/virtio_ring.h | 61 +++++++++++++------ 2 files changed,

This is a follow up of the discussion in this thread: https://patchwork.ozlabs.org/patch/1001015/#2042353 Tiwei Bie (3): virtio_ring: define flags as shifts consistently virtio_ring: add VIRTIO_RING_NO_LEGACY virtio_ring: use new vring flags drivers/virtio/virtio_ring.c | 100 ++++++++++++++++++------------- include/uapi/linux/virtio_ring.h | 61 +++++++++++++------ 2 files changed,

Switch to using the _SPLIT_ and _PACKED_ variants of vring flags in split ring and packed ring respectively. Signed-off-by: Tiwei Bie <tiwei.bie at intel.com> --- drivers/virtio/virtio_ring.c | 100 +++++++++++++++++++++-------------- 1 file changed, 59 insertions(+), 41 deletions(-) diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c index cd7e755484e3..2806f69c6c9f

Hello everyone, This patch set implements packed ring support in virtio driver. Some functional tests have been done with Jason's packed ring implementation in vhost: https://lkml.org/lkml/2018/7/3/33 Both of ping and netperf worked as expected. RFC (v6) -> v1: - Avoid extra virtio_wmb() in virtqueue_enable_cb_delayed_packed() when event idx is off (Jason); - Fix bufs calculation in

Hello everyone, This RFC implements packed ring support in virtio driver. Some simple functional tests have been done with Jason's packed ring implementation in vhost: https://lkml.org/lkml/2018/4/23/12 Both of ping and netperf worked as expected (with EVENT_IDX disabled). But there are below known issues: 1. Reloading the guest driver will break the Tx/Rx; 2. Zeroing the flags when

Hello everyone, This patch set implements packed ring support in virtio driver. Some functional tests have been done with Jason's packed ring implementation in vhost: https://lkml.org/lkml/2018/7/3/33 Both of ping and netperf worked as expected. v1 -> v2: - Use READ_ONCE() to read event off_wrap and flags together (Jason); - Add comments related to ccw (Jason); RFC (v6) -> v1: -

Hello everyone, This patch set implements packed ring support in virtio driver. Some functional tests have been done with Jason's packed ring implementation in vhost: https://lkml.org/lkml/2018/7/3/33 Both of ping and netperf worked as expected. v1 -> v2: - Use READ_ONCE() to read event off_wrap and flags together (Jason); - Add comments related to ccw (Jason); RFC (v6) -> v1: -

Hello everyone, This RFC implements packed ring support in virtio driver. Some functional tests have been done with Jason's packed ring implementation in vhost (RFC v5): https://lwn.net/Articles/755862/ Both of ping and netperf worked as expected. TODO: - Refinements (for code and commit log); - More tests and bug fixes if any; - Send the formal patch set; RFC v5 -> RFC v6: - Avoid

Hello everyone, This RFC implements packed ring support in virtio driver. Some simple functional tests have been done with Jason's packed ring implementation in vhost (RFC v4): https://lkml.org/lkml/2018/5/16/501 Both of ping and netperf worked as expected w/ EVENT_IDX disabled. Ping worked as expected w/ EVENT_IDX enabled, but netperf didn't (A hack has been added in the driver to