diff options
| author | Dag Moxnes <dag.moxnes@oracle.com> | 2019-10-30 13:44:00 +0100 |
|---|---|---|
| committer | Jason Gunthorpe <jgg@mellanox.com> | 2019-11-17 10:37:00 -0400 |
| commit | e1ee1e62bec4a8968355517ea11b2a06b7364408 (patch) | |
| tree | 2803c2a79f2820d1e3132677ece6ace3e4f885fd /drivers | |
| parent | 72b894b09a96b741c92562709f6629310f2b34a1 (diff) | |
| download | linux-e1ee1e62bec4a8968355517ea11b2a06b7364408.tar.bz2 | |
RDMA/cma: Use ACK timeout for RoCE packetLifeTime
The cma is currently using a hard-coded value, CMA_IBOE_PACKET_LIFETIME,
for the PacketLifeTime, as it can not be determined from the network.
This value might not be optimal for all networks.
The cma module supports the function rdma_set_ack_timeout to set the ACK
timeout for a QP associated with a connection. As per IBTA 12.7.34 local
ACK timeout = (2 * PacketLifeTime + Local CA’s ACK delay). Assuming a
negligible local ACK delay, we can use PacketLifeTime = local ACK
timeout/2 as a reasonable approximation for RoCE networks.
Link: https://lore.kernel.org/r/1572439440-17416-1-git-send-email-dag.moxnes@oracle.com
Signed-off-by: Dag Moxnes <dag.moxnes@oracle.com>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/infiniband/core/cma.c | 15 |
1 files changed, 13 insertions, 2 deletions
diff --git a/drivers/infiniband/core/cma.c b/drivers/infiniband/core/cma.c index abf249d277ad..25f2b70fd8ef 100644 --- a/drivers/infiniband/core/cma.c +++ b/drivers/infiniband/core/cma.c @@ -2504,7 +2504,9 @@ EXPORT_SYMBOL(rdma_set_service_type); * This function should be called before rdma_connect() on active side, * and on passive side before rdma_accept(). It is applicable to primary * path only. The timeout will affect the local side of the QP, it is not - * negotiated with remote side and zero disables the timer. + * negotiated with remote side and zero disables the timer. In case it is + * set before rdma_resolve_route, the value will also be used to determine + * PacketLifeTime for RoCE. * * Return: 0 for success */ @@ -2913,7 +2915,16 @@ static int cma_resolve_iboe_route(struct rdma_id_private *id_priv) route->path_rec->rate = iboe_get_rate(ndev); dev_put(ndev); route->path_rec->packet_life_time_selector = IB_SA_EQ; - route->path_rec->packet_life_time = CMA_IBOE_PACKET_LIFETIME; + /* In case ACK timeout is set, use this value to calculate + * PacketLifeTime. As per IBTA 12.7.34, + * local ACK timeout = (2 * PacketLifeTime + Local CA’s ACK delay). + * Assuming a negligible local ACK delay, we can use + * PacketLifeTime = local ACK timeout/2 + * as a reasonable approximation for RoCE networks. + */ + route->path_rec->packet_life_time = id_priv->timeout_set ? + id_priv->timeout - 1 : CMA_IBOE_PACKET_LIFETIME; + if (!route->path_rec->mtu) { ret = -EINVAL; goto err2; |