netdev - Re: small RPS cache for fragments?

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:	Tue, 17 May 2011 14:44:42 -0700
From:	Andi Kleen <andi@...stfloor.org>
To:	Eric Dumazet <eric.dumazet@...il.com>
Cc:	David Miller <davem@...emloft.net>, netdev@...r.kernel.org
Subject: Re: small RPS cache for fragments?

Eric Dumazet <eric.dumazet@...il.com> writes:
>
> OK but do we have workloads actually needing this optimization at all ?

That's a good a question.
>
> (IP defrag hits a read_lock(&ip4_frags.lock)), so maybe steer all frags
> on a given cpu ?)

Couldn't the lock just be replaced with a hashed or bitmap lock or 
bit in low bits of pointer lock?

iirc it just protects the heads of the hash table.

They're not rwlocks, but especially if the locking was more finegrained
that's likely not needed anymore.

-Andi

-- 
ak@...ux.intel.com -- Speaking for myself only
--
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