netdev - Re: [PATCH] test_bpf: add a schedule point

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: <52973140-9bbf-97f9-542b-cfe1124da81f@iogearbox.net>
Date:   Tue, 27 Feb 2018 09:51:04 +0100
From:   Daniel Borkmann <daniel@...earbox.net>
To:     Eric Dumazet <eric.dumazet@...il.com>,
        Alexei Starovoitov <ast@...nel.org>
Cc:     netdev <netdev@...r.kernel.org>
Subject: Re: [PATCH] test_bpf: add a schedule point

On 02/27/2018 01:12 AM, Eric Dumazet wrote:
> On Mon, 2018-02-26 at 21:11 +0100, Daniel Borkmann wrote:
>> On 02/26/2018 07:52 PM, Eric Dumazet wrote:
>>> From: Eric Dumazet <edumazet@...gle.com>
>>>
>>> test_bpf() is taking 1.6 seconds nowadays, it is time
>>> to add a schedule point in it.
>>>
>>> Signed-off-by: Eric Dumazet <edumazet@...gle.com>
>>
>> Applied to bpf tree, thanks Eric!
> 
> Thanks Daniel
> 
> Note that some BPF programs are quite expensive
> 
> [  173.447471] test_bpf: #264 BPF_MAXINSNS: Call heavy transformations jited:1 19248 18548 PASS
> jited:1 12519 PASS
> [  173.509228] test_bpf: #269 BPF_MAXINSNS: ld_abs+get_processor_id jited:1 20896 PASS
> 
> So we can still consume ~200 ms per test, without cond_resched()
> 
> Maybe reducing MAX_TESTRUNS from 10000 to 1000 would be the next step ?

Yeah, that's totally fine with me, please feel free to send a patch. Another step on
todo is to reduce the test cases from test_bpf and move them into the test_verifier's
run-time testing where applicable. Would be nice if at some point we can get rid of
test_bpf and have everything consolidated within test_verifier.