netdev - Re: [PATCH net-next-2.6] ipv4: more compliant RFC 3168 support

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: <20110516213336.GD3290@nuttenaction>
Date:	Mon, 16 May 2011 23:33:37 +0200
From:	Hagen Paul Pfeifer <hagen@...u.net>
To:	Eric Dumazet <eric.dumazet@...il.com>
Cc:	Stefanos Harhalakis <v13@....gr>,
	David Miller <davem@...emloft.net>,
	netdev <netdev@...r.kernel.org>
Subject: Re: [PATCH net-next-2.6] ipv4: more compliant RFC 3168 support

* Eric Dumazet | 2011-05-15 18:01:50 [+0200]:

>Problem of this version is that common frames in the Internet (NOT_ECT
>or ECT_X or ECT_X) will take the longest path to come to "return 0;"
>
>a switch() version is fast because gcc emits a table based jump

Sure? Is the table access not an dCache miss? E.g.

4003dc: ff 24 fd 58 06 40 00  jmpq   *0x400658(,%rdi,8)

Not sure if jump table access is superior these days ...


Hagen
--
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