From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S1752738AbaBMWdc (ORCPT <rfc822;w@1wt.eu>);
	Thu, 13 Feb 2014 17:33:32 -0500
Received: from terminus.zytor.com ([198.137.202.10]:45115 "EHLO mail.zytor.com"
	rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP
	id S1751795AbaBMWd3 (ORCPT <rfc822;linux-kernel@vger.kernel.org>);
	Thu, 13 Feb 2014 17:33:29 -0500
Message-ID: <52FD47F9.2090907@zytor.com>
Date: Thu, 13 Feb 2014 14:32:25 -0800
From: "H. Peter Anvin" <hpa@zytor.com>
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.2.0
MIME-Version: 1.0
To: Alexei Starovoitov <ast@plumgrid.com>,
        Daniel Borkmann <dborkman@redhat.com>
CC: Ingo Molnar <mingo@kernel.org>, "David S. Miller" <davem@davemloft.net>,
        Steven Rostedt <rostedt@goodmis.org>,
        Peter Zijlstra <a.p.zijlstra@chello.nl>,
        Thomas Gleixner <tglx@linutronix.de>,
        Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>,
        Tom Zanussi <tom.zanussi@linux.intel.com>,
        Jovi Zhangwei <jovi.zhangwei@gmail.com>,
        Eric Dumazet <edumazet@google.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Frederic Weisbecker <fweisbec@gmail.com>,
        Arnaldo Carvalho de Melo <acme@infradead.org>,
        Pekka Enberg <penberg@iki.fi>, Arjan van de Ven <arjan@infradead.org>,
        Christoph Hellwig <hch@infradead.org>, linux-kernel@vger.kernel.org,
        netdev@vger.kernel.org
Subject: Re: [RFC PATCH v2 tip 0/7] 64-bit BPF insn set and tracing filters
References: <1391649046-4383-1-git-send-email-ast@plumgrid.com>	<52F3670D.5090608@redhat.com> <CAMEtUuza3NuM7L0RnVVgU-MTfjE2M==8wb4UY2TAo0Pg6DKZqA@mail.gmail.com>
In-Reply-To: <CAMEtUuza3NuM7L0RnVVgU-MTfjE2M==8wb4UY2TAo0Pg6DKZqA@mail.gmail.com>
X-Enigmail-Version: 1.6
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On 02/06/2014 05:20 PM, Alexei Starovoitov wrote:
> 
> I believe that old BPF outlived itself and BPF64 should
> replace it in all current use cases plus a lot more.
> It just cannot happen at once.
> BPF64 can come in. bpf32->bpf64 converter functioning.
> JIT from bpf64->aarch64 and may be sparc64 needs to be in place.
> Then old bpf can fade away.
> 

I don't think that is doable any time soon.  Right now pretty much all
mobile devices, for example, are 32 bits and they really want to use
syscall filtering for security.  Performance matters greatly there.

As such, 32-bit JIT support is going to be very important for a long
time to come.

	-hpa