prov/efa: Minimize calls to efa_rdm_ep_get_peer in the CQ read path #10848
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This change is necessary to implement an implicit AV. With an implicit AV, using the fi_addr is no longer an option for identifying different peers. All unknown peers will have fi_addr set to -1. And the index in the implicit AV can be re-used, so it's not guaranteed to be unique. This commit makes the rxe_map part of the peer struct and only uses the msg_id as the hash key Signed-off-by: Sai Sunku <[email protected]>
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This change is useful for two reasons (1) The efa_rdm_ep_get_peer function accesses the AV and it's easier to lock access to the AV when the call happens in fewer places (2) With an implicit AV, the fi_addr will always be -1 for peers not explicitly inserted to the AV. So efa_rdm_ep_get_peer will need to do a reverse hashmap lookup with a significant performance cost for such peers. So minimizing the number of calls to efa_rdm_ep_get_peer is more performant. Signed-off-by: Sai Sunku <[email protected]>
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This change is useful for two reasons
(1) The efa_rdm_ep_get_peer function accesses the AV and it's easier to
lock access to the AV when the call happens in fewer places
(2) With an implicit AV, the fi_addr will always be -1 for peers not
explicitly inserted to the AV. So efa_rdm_ep_get_peer will need to do
a reverse hashmap lookup with a significant performance cost for such
peers. So minimizing the number of calls to efa_rdm_ep_get_peer is more
performant.