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Date: Mon, 1 Nov 2010 14:56:55 -0400
Message-ID: <AANLkTikWKkQYa1JtkEymV7Rc+ePpfce=8mDTADEv2nUp@mail.gmail.com>
Subject: Re: [ath9k-devel] [RFC] ath9k: Insert wmb before linking dma descriptors
From: Bob Copeland <me@bobcopeland.com>
To: =?ISO-8859-1?Q?Bj=F6rn_Smedman?= <bjorn.smedman@venatech.se>
Cc: "Luis R. Rodriguez" <mcgrof@gmail.com>,
	Felix Fietkau <nbd@openwrt.org>,
	Ben Greear <greearb@candelatech.com>,
	linux-wireless <linux-wireless@vger.kernel.org>,
	"John W. Linville" <linville@tuxdriver.com>,
	"ath9k-devel@venema.h4ckr.net" <ath9k-devel@venema.h4ckr.net>
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2010/11/1 Bj?rn Smedman <bjorn.smedman@venatech.se>:
> 2010/11/1 Bob Copeland <me@bobcopeland.com>:
>> late-comers know which data is serialized by the barrier. ?In the best
>> case, said late-comers are more knowledgeable than me and fix the crap
>> code that I write.
>
> First let me apologize for the tone in my previous mail. It came out
> too hard this Monday (due to a long and unwanted weekend of debugging
> ath9k DMA errors). I did not mean to suggest that any code is crap
> regardless of origin (except maybe if I wrote it).

Err, no worries, I don't think anyone took it that way (I don't do much
ath9k stuff anyway).  I literally meant my own code is often crap so I
try to leave breadcrumbs for people, esp for nitpicky things like
barriers :)

> Thanx Bob for your input. If we agree the memory barriers are needed
> for correctness I will add comments and post as PATCH.

Sure, my opinion may not matter for ath9k, but I think it is a good
idea.

-- 
Bob Copeland %% www.bobcopeland.com