[PATCH 1/2] net: thunderx: Set recevie buffer page usage count in bulk

Sunil Kovvuri sunil.kovvuri at gmail.com
Mon Mar 7 08:58:39 PST 2016


Hi David,

>> you create a window of time during which the consumer
>> can release the page and prematurely free it.
Okay, but here the consumer i.e HW is notified only after page count
is incremented.
For example if you check 'nicvf_refill_rbdr' fn() only after receive
buffer ring is
refilled with buffers, doorbell is issued to hardware to start using
the new buffers.

So
@@ -241,6 +254,8 @@ refill:
                new_rb++;
        }

+       nicvf_get_page(nic);
+
calling 'nicvf_get_page' before issuing doorbell ensures page ref
count is properly
set before hw/consumer can use the buffers.

Thanks,
Sunil.



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