Re: [PATCH net-next v6 07/11] net/smc: register loopback-ism into SMC-D device list

Wenjia Zhang
2024-04-25T11:30:11Z

On 14.04.24 06:03, Wen Gu wrote:
> After the loopback-ism device is ready, add it to the SMC-D device list
> as an ISMv2 device, and always keep it at the beginning to ensure it is
> preferred for providing a shortcut for data transfer within the same
> kernel.
>
> Signed-off-by: Wen Gu <guwen@linux.alibaba.com>
> ---
> net/smc/smc_ism.c | 30 +++++++++++++++++++++---------
> net/smc/smc_ism.h | 1 +
> net/smc/smc_loopback.c | 20 +++++++++++++-------
> 3 files changed, 35 insertions(+), 16 deletions(-)
>
> diff --git a/net/smc/smc_ism.c b/net/smc/smc_ism.c
> index 188fd28423c2..6bed0a61b746 100644
> --- a/net/smc/smc_ism.c
> +++ b/net/smc/smc_ism.c
> @@ -91,6 +91,11 @@ bool smc_ism_is_v2_capable(void)
> return smc_ism_v2_capable;
> }
>
> +void smc_ism_set_v2_capable(void)
> +{
> + smc_ism_v2_capable = true;
> +}
> +
> /* Set a connection using this DMBE. */
> void smc_ism_set_conn(struct smc_connection *conn)
> {
> @@ -439,7 +444,7 @@ static struct smcd_dev *smcd_alloc_dev(struct device *parent, const char *name,
> static void smcd_register_dev(struct ism_dev *ism)
> {
> const struct smcd_ops *ops = ism_get_smcd_ops();
> - struct smcd_dev *smcd;
> + struct smcd_dev *smcd, *fentry;
>
> if (!ops)
> return;
> @@ -454,16 +459,23 @@ static void smcd_register_dev(struct ism_dev *ism)
> if (smc_pnetid_by_dev_port(&ism->pdev->dev, 0, smcd->pnetid))
> smc_pnetid_by_table_smcd(smcd);
>
> + if (smcd->ops->supports_v2())
> + smc_ism_set_v2_capable();
> mutex_lock(&smcd_dev_list.mutex);
> - if (list_empty(&smcd_dev_list.list)) {
> - if (smcd->ops->supports_v2())
> - smc_ism_v2_capable = true;
> - }
> - /* sort list: devices without pnetid before devices with pnetid */
> - if (smcd->pnetid[0])
> + /* sort list:
> + * - devices without pnetid before devices with pnetid;
> + * - loopback-ism always at the very beginning;
> + */
> + if (!smcd->pnetid[0]) {
> + fentry = list_first_entry_or_null(&smcd_dev_list.list,
> + struct smcd_dev, list);
> + if (fentry && smc_ism_is_loopback(fentry))
> + list_add(&smcd->list, &fentry->list);
> + else
> + list_add(&smcd->list, &smcd_dev_list.list);
> + } else {
> list_add_tail(&smcd->list, &smcd_dev_list.list);
> - else
> - list_add(&smcd->list, &smcd_dev_list.list);
> + }

Nit: here the pair of curly brackets are unnecessary. …