[ofa-general] Re: [PATCH] IB/ipoib: IPOIB CM rx use higher order fragments

[Pradeep Satyanarayana]

> 
> Other drivers do similar allocations. For example, e1000 when working
> with jumbo frames does such large allocations. Also I did not notice
> allocation failures though my system was pretty much active but I can
> monitor for such possible failures.
> 
> e1000_main.c line 3549:
> 
> else if (max_frame <= E1000_RXBUFFER_16384)
> 		adapter->rx_buffer_len = E1000_RXBUFFER_16384;
>

It looks like E1000_RXBUFFER_16384 is used by e1000_setup_rctl() to 
configure the receive control registers. The actual allocation of 
buffers happens in e1000_alloc_rx_buffers_ps() wherein 3 pages are 
allocated through alloc_page(GFP_ATOMIC) for the case of jumbo frames.

Pradeep