| Message ID | cover.1706725638.git.limings@nvidia.com |
|---|---|
| Headers | show |
| Series | platform/mellanox: mlxbf-tmfifo: Drop Tx network packet when Tx TmFIFO is full | expand |
On 31-01-2024 19:32, Liming Sun wrote: > BugLink: https://bugs.launchpad.net/bugs/2051871 > > SRU Justification: > > [Impact] > This is a cherry-pick fix from upstream to drop Tx network packet > when Tx TmFIFO is full. > > [Fix] > Starting from Linux 5.16 kernel, Tx timeout mechanism was added > in the virtio_net driver which prints the "Tx timeout" warning > message when a packet stays in Tx queue for too long. Below is an > example of the reported message: > > "[494105.316739] virtio_net virtio1 tmfifo_net0: TX timeout on > queue: 0, sq: output.0, vq: 0×1, name: output.0, usecs since > last trans: 3079892256". > > This issue could happen when external host driver which drains the > FIFO is restared, stopped or upgraded. To avoid such confusing > "Tx timeout" messages, this commit adds logic to drop the outstanding > Tx packet if it's not able to transmit in two seconds due to Tx FIFO > full, which can be considered as congestion or out-of-resource drop. > > This commit also handles the special case that the packet is half- > transmitted into the Tx FIFO. In such case, the packet is discarded > with remaining length stored in vring->rem_padding. So paddings with > zeros can be sent out when Tx space is available to maintain the > integrity of the packet format. The padded packet will be dropped on > the receiving side. > > [Test Case] > Same functionality and testing as on BlueField-1/2/3. No functionality > change. > > [Regression Potential] > Same behavior from user perspective. > > [Other] > n/a > > > Liming Sun (1): > [SRU][J:linux-bluefield] platform/mellanox: mlxbf-tmfifo: Drop Tx > network packet when Tx TmFIFO is full > > drivers/platform/mellanox/mlxbf-tmfifo.c | 67 ++++++++++++++++++++++++ > 1 file changed, 67 insertions(+) > Acked-by: Thibault Ferrante <thibault.ferrante@canonical.com> -- Thibault
Acked-by: Bartlomiej Zolnierkiewicz <bartlomiej.zolnierkiewicz@canonical.com> On Wed, Jan 31, 2024 at 7:33 PM Liming Sun <limings@nvidia.com> wrote: > > BugLink: https://bugs.launchpad.net/bugs/2051871 > > SRU Justification: > > [Impact] > This is a cherry-pick fix from upstream to drop Tx network packet > when Tx TmFIFO is full. > > [Fix] > Starting from Linux 5.16 kernel, Tx timeout mechanism was added > in the virtio_net driver which prints the "Tx timeout" warning > message when a packet stays in Tx queue for too long. Below is an > example of the reported message: > > "[494105.316739] virtio_net virtio1 tmfifo_net0: TX timeout on > queue: 0, sq: output.0, vq: 0×1, name: output.0, usecs since > last trans: 3079892256". > > This issue could happen when external host driver which drains the > FIFO is restared, stopped or upgraded. To avoid such confusing > "Tx timeout" messages, this commit adds logic to drop the outstanding > Tx packet if it's not able to transmit in two seconds due to Tx FIFO > full, which can be considered as congestion or out-of-resource drop. > > This commit also handles the special case that the packet is half- > transmitted into the Tx FIFO. In such case, the packet is discarded > with remaining length stored in vring->rem_padding. So paddings with > zeros can be sent out when Tx space is available to maintain the > integrity of the packet format. The padded packet will be dropped on > the receiving side. > > [Test Case] > Same functionality and testing as on BlueField-1/2/3. No functionality > change. > > [Regression Potential] > Same behavior from user perspective. > > [Other] > n/a > > > Liming Sun (1): > [SRU][J:linux-bluefield] platform/mellanox: mlxbf-tmfifo: Drop Tx > network packet when Tx TmFIFO is full > > drivers/platform/mellanox/mlxbf-tmfifo.c | 67 ++++++++++++++++++++++++ > 1 file changed, 67 insertions(+) >
On 24/01/31 01:32PM, Liming Sun wrote: > BugLink: https://bugs.launchpad.net/bugs/2051871 > > SRU Justification: > > [Impact] > This is a cherry-pick fix from upstream to drop Tx network packet > when Tx TmFIFO is full. > > [Fix] > Starting from Linux 5.16 kernel, Tx timeout mechanism was added > in the virtio_net driver which prints the "Tx timeout" warning > message when a packet stays in Tx queue for too long. Below is an > example of the reported message: > > "[494105.316739] virtio_net virtio1 tmfifo_net0: TX timeout on > queue: 0, sq: output.0, vq: 0×1, name: output.0, usecs since > last trans: 3079892256". > > This issue could happen when external host driver which drains the > FIFO is restared, stopped or upgraded. To avoid such confusing > "Tx timeout" messages, this commit adds logic to drop the outstanding > Tx packet if it's not able to transmit in two seconds due to Tx FIFO > full, which can be considered as congestion or out-of-resource drop. > > This commit also handles the special case that the packet is half- > transmitted into the Tx FIFO. In such case, the packet is discarded > with remaining length stored in vring->rem_padding. So paddings with > zeros can be sent out when Tx space is available to maintain the > integrity of the packet format. The padded packet will be dropped on > the receiving side. > > [Test Case] > Same functionality and testing as on BlueField-1/2/3. No functionality > change. > > [Regression Potential] > Same behavior from user perspective. > > [Other] > n/a > > > Liming Sun (1): > [SRU][J:linux-bluefield] platform/mellanox: mlxbf-tmfifo: Drop Tx > network packet when Tx TmFIFO is full > > drivers/platform/mellanox/mlxbf-tmfifo.c | 67 ++++++++++++++++++++++++ > 1 file changed, 67 insertions(+) Acked-by: Andrei Gherzan <andrei.gherzan@canonical.com>
Applied to jammy:linux-bluefield/master-next. Thanks. -- Best regards, Bartlomiej On Wed, Jan 31, 2024 at 7:33 PM Liming Sun <limings@nvidia.com> wrote: > > BugLink: https://bugs.launchpad.net/bugs/2051871 > > SRU Justification: > > [Impact] > This is a cherry-pick fix from upstream to drop Tx network packet > when Tx TmFIFO is full. > > [Fix] > Starting from Linux 5.16 kernel, Tx timeout mechanism was added > in the virtio_net driver which prints the "Tx timeout" warning > message when a packet stays in Tx queue for too long. Below is an > example of the reported message: > > "[494105.316739] virtio_net virtio1 tmfifo_net0: TX timeout on > queue: 0, sq: output.0, vq: 0×1, name: output.0, usecs since > last trans: 3079892256". > > This issue could happen when external host driver which drains the > FIFO is restared, stopped or upgraded. To avoid such confusing > "Tx timeout" messages, this commit adds logic to drop the outstanding > Tx packet if it's not able to transmit in two seconds due to Tx FIFO > full, which can be considered as congestion or out-of-resource drop. > > This commit also handles the special case that the packet is half- > transmitted into the Tx FIFO. In such case, the packet is discarded > with remaining length stored in vring->rem_padding. So paddings with > zeros can be sent out when Tx space is available to maintain the > integrity of the packet format. The padded packet will be dropped on > the receiving side. > > [Test Case] > Same functionality and testing as on BlueField-1/2/3. No functionality > change. > > [Regression Potential] > Same behavior from user perspective. > > [Other] > n/a > > > Liming Sun (1): > [SRU][J:linux-bluefield] platform/mellanox: mlxbf-tmfifo: Drop Tx > network packet when Tx TmFIFO is full > > drivers/platform/mellanox/mlxbf-tmfifo.c | 67 ++++++++++++++++++++++++ > 1 file changed, 67 insertions(+) >
BugLink: https://bugs.launchpad.net/bugs/2051871 SRU Justification: [Impact] This is a cherry-pick fix from upstream to drop Tx network packet when Tx TmFIFO is full. [Fix] Starting from Linux 5.16 kernel, Tx timeout mechanism was added in the virtio_net driver which prints the "Tx timeout" warning message when a packet stays in Tx queue for too long. Below is an example of the reported message: "[494105.316739] virtio_net virtio1 tmfifo_net0: TX timeout on queue: 0, sq: output.0, vq: 0×1, name: output.0, usecs since last trans: 3079892256". This issue could happen when external host driver which drains the FIFO is restared, stopped or upgraded. To avoid such confusing "Tx timeout" messages, this commit adds logic to drop the outstanding Tx packet if it's not able to transmit in two seconds due to Tx FIFO full, which can be considered as congestion or out-of-resource drop. This commit also handles the special case that the packet is half- transmitted into the Tx FIFO. In such case, the packet is discarded with remaining length stored in vring->rem_padding. So paddings with zeros can be sent out when Tx space is available to maintain the integrity of the packet format. The padded packet will be dropped on the receiving side. [Test Case] Same functionality and testing as on BlueField-1/2/3. No functionality change. [Regression Potential] Same behavior from user perspective. [Other] n/a Liming Sun (1): [SRU][J:linux-bluefield] platform/mellanox: mlxbf-tmfifo: Drop Tx network packet when Tx TmFIFO is full drivers/platform/mellanox/mlxbf-tmfifo.c | 67 ++++++++++++++++++++++++ 1 file changed, 67 insertions(+)