prov/rxm : Corrected rxm to return an existing MR key in its MR Map. #10371
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if an key/item already exists in its MR map rxm returns an error instead of reflecting the behaviour of the underlying core provider viz returning a key. This patch corrects the behaviour by returning a success to make sure it is consistent with the core provider's behaviour. Signed-off-by: Nikhil Nanal <nikhil.nanal@intel.com>
| if (ret != -FI_ENOKEY) | ||
| FI_WARN(&rxm_prov, FI_LOG_DOMAIN, | ||
| "MR map insert for atomic verification failed %d\n", | ||
| ret); |
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In the case of FI_ENOKEY, the key in the mr_map is still associated with an old rxm_mr, which apparently is still valid. We are now in a situation that a key is associated with multiple rxm_mr's, but only one is present in the mr_map.
In rxm_handle_atomic_req, rxm_mr_get_map_entry is called to retrieve the rxm_mr associated with the key. In this case, the old rxm_mr is going to be referenced. That may or may not work as expected. If one close the old rxm_mr. The key will be removed from the mr_map. The atomic req processing would fail even though it shouldn't.
I don't have a good solution for this. It's basically a behavior confliction of cached MR at verbs level and non-cached behavior of the mr_map at rxm level.
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would it make sense to do a lookup before inserting the rxm_mr and only insert if lookup fails?
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That doesn't make any difference. The mr_map is mainly used to find rxm_mr with a key. There can be only one association in mr_map, but we have multiple rxm_mr's.
if an key/item already exists in its MR map rxm returns an error instead of reflecting the behaviour of the underlying core provider viz returning a key. This patch corrects the behaviour by returning a success to make sure it is consistent with the core provider's behaviour.