From mboxrd@z Thu Jan 1 00:00:00 1970 From: Larry Finger Subject: Re: [PATCH] b43: Increase number of RX DMA slots Date: Tue, 19 Feb 2013 20:42:02 -0600 Message-ID: <512437FA.2030105@lwfinger.net> References: <20130219.005206.397289032011003833.davem@davemloft.net> <5123BCFF.5090408@lwfinger.net> <20130219.131553.787630407148880340.davem@davemloft.net> <5123C43D.2020602@lwfinger.net> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: David Miller , David.Laight@aculab.com, linville@tuxdriver.com, linux-wireless@vger.kernel.org, netdev@vger.kernel.org, bittorf@bluebottle.com, stable@vger.kernel.org To: Julian Calaby Return-path: Received: from mail-qc0-f175.google.com ([209.85.216.175]:39261 "EHLO mail-qc0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934588Ab3BTCmI (ORCPT ); Tue, 19 Feb 2013 21:42:08 -0500 In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: On 02/19/2013 06:47 PM, Julian Calaby wrote: > > Is it be possible to increase the number of slots at runtime? Maybe an > even better solution would be to keep the existing number of slots, > and if they run out, reset and increase incrementally to some sensible > maximum value. The number could be increased a bit, but on systems with 32-bit DMA such as the BCM4318, the maximum size of the ring buffer is 4KB. Even more importantly, each slot is allocated an skb of 2390 bytes. Even at 256 slots, the memory allocation is pretty large. Larry