From: Oliver Hartkopp <socketcan@hartkopp.net>
To: Marc Kleine-Budde <mkl@pengutronix.de>, linux-can@vger.kernel.org
Cc: netdev@vger.kernel.org
Subject: Re: [PATCH RFC v2 1/2] can: fix multiple delivery of a single CAN frame for overlapping CAN filters
Date: Tue, 31 Mar 2015 22:24:20 +0200 [thread overview]
Message-ID: <551B0274.1010900@hartkopp.net> (raw)
In-Reply-To: <551A93D0.6000302@pengutronix.de>
On 31.03.2015 14:32, Marc Kleine-Budde wrote:
> On 03/30/2015 12:41 PM, Oliver Hartkopp wrote:
>> Please check out
>>
>> https://www.kernel.org/pub/linux/kernel/people/rusty/kernel-locking/
>>
>> And especially
>> https://www.kernel.org/pub/linux/kernel/people/rusty/kernel-locking/x173.html#LOCK-SOFTIRQS-SAME
>>
>> When a softirq processes an incoming skb this remains on that selected CPU.
>
> Okay, I was not sure about this. What about preempt_rt?
>
I don't care :-)
There are so many implementations that rely on this per-CPU stuff that we can
assume preempt_rt takes care of it (e.g. with locking or reducing CPU cores, etc)
>> Putting a struct into these percpu handling can be done - but does it increase
>> the readability in this case?
>
> It saves ressources, 1 pointer instead of 3 (considering both of your
> patches) and only 1 allocation.
Yes. I did some more code reading, created a struct for it and omitted the
initialization as alloc_percpu returns an already zero'ed memory region.
Will send tomorrow morning.
Regards,
Oliver
next prev parent reply other threads:[~2015-03-31 20:24 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-03-29 18:09 [PATCH RFC v2 0/2] can: join filters with per-CPU variables Oliver Hartkopp
2015-03-29 18:09 ` [PATCH RFC v2 1/2] can: fix multiple delivery of a single CAN frame for overlapping CAN filters Oliver Hartkopp
2015-03-30 9:50 ` Marc Kleine-Budde
2015-03-30 10:29 ` Oliver Hartkopp
2015-03-30 10:36 ` Marc Kleine-Budde
2015-03-30 10:10 ` Marc Kleine-Budde
2015-03-30 10:16 ` Marc Kleine-Budde
2015-03-30 10:41 ` Oliver Hartkopp
2015-03-31 12:32 ` Marc Kleine-Budde
2015-03-31 20:24 ` Oliver Hartkopp [this message]
2015-03-30 12:33 ` Sergei Shtylyov
2015-03-30 15:49 ` Oliver Hartkopp
2015-03-30 17:14 ` Sergei Shtylyov
2015-03-30 17:25 ` Oliver Hartkopp
2015-03-29 18:09 ` [PATCH RFC v2 2/2] can: introduce new raw socket option to join the given " Oliver Hartkopp
2015-03-31 12:36 ` Marc Kleine-Budde
2015-03-31 20:30 ` Oliver Hartkopp
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