linux-kernel - Re: [PATCH] radeon: Deinline indirect register accessor functions

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <555A37CC.2020809@amd.com>
Date:	Mon, 18 May 2015 21:04:44 +0200
From:	Christian König <christian.koenig@....com>
To:	Denys Vlasenko <dvlasenk@...hat.com>
CC:	Alex Deucher <alexander.deucher@....com>,
	<linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] radeon: Deinline indirect register accessor functions

On 18.05.2015 20:50, Denys Vlasenko wrote:
> On 05/18/2015 08:06 PM, Christian König wrote:
>> I'm actually surprised how often people come along with that. The last time we tried this it caused a noticeable performance drop.
>>
>> Basic problem is that this line:
>>> +    if ((reg < rdev->rmmio_size || reg < RADEON_MIN_MMIO_SIZE) && !always_indirect)
>> optimizes away in most of the cases which reduces the call to a readl which is way faster than the spinlock path.
>>
>> So this is a NAK,
>
> Fair enough.
>
> I'm preparing a v2 where the fast branch of r100_mm_{r,w}reg() will stay inlined.
>
Sounds good to be, but IIRC that was suggested the last time this came 
up as well. You might just want to google a bit why it wasn't done like 
this before submitting the patch for review.

BTW: Please CC the dri-devel list as well, cause not everybody is 
reading on linux-kernel.

Regards,
Christian.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/