netdev - Re: irq disable in __netdev_alloc

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]

Date:	Wed, 22 Oct 2014 20:51:16 -0700
From:	Eric Dumazet <eric.dumazet@...il.com>
To:	Alexander Duyck <alexander.duyck@...il.com>
Cc:	Alexei Starovoitov <ast@...mgrid.com>,
	Eric Dumazet <edumazet@...gle.com>,
	Network Development <netdev@...r.kernel.org>
Subject: Re: irq disable in __netdev_alloc_frag() ?

On Wed, 2014-10-22 at 20:19 -0700, Alexander Duyck wrote:

> Couldn't __netdev_alloc_frag() be forked into two functions, one that is
> only called from inside the NAPI context and one that is called for all
> other contexts?  It would mean having to double the number of pages
> being held per CPU, but I would think something like that would be doable.

Possibly, but this looks like code bloat for me.

On my hosts, this hard irq masking is pure noise.

What CPU are you using Alexander ?

Same could be done with some kmem_cache_alloc() : SLAB uses hard irq
masking while some caches are never used from hard irq context.



--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html