[ofa-general] [PATCH RFC] ib_mthca: avoid recycling FMR R_Keys too soon

[Jack Morgenstein]

On Thursday 21 February 2008 17:49, Or Gerlitz wrote:
> Is it possible to never re-initialize the key? if yes, what's the 
> semantics of the M=max_map_per_fmr device attribute? I was thinking that 
> after the fmr was mapped M times, something --has-- to be reinitialized, 
> sorry if this is my misunderstanding, can you clarify that?
> 
It does not have to be re-initialized.  However, the cache needs to be flushed
(SYNC_TPT), so that we do not have the same 32-bit key multiple times in the
cache.

The "something" which must be done is to flush the cache.  Once the cache is
flushed, we again have max_map_per_fmr remap possibilities, and we don't care
what the initial sequence value is.  However, the index value MUST be the
same as it was before.

- Jack