netdev - Re: [PATCH net] test_bpf: reduce MAX

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Date:   Wed, 28 Feb 2018 11:58:31 -0500 (EST)
From:   David Miller <davem@...emloft.net>
To:     eric.dumazet@...il.com
Cc:     daniel@...earbox.net, ast@...nel.org, netdev@...r.kernel.org
Subject: Re: [PATCH net] test_bpf: reduce MAX_TESTRUNS

From: Eric Dumazet <eric.dumazet@...il.com>
Date: Wed, 28 Feb 2018 08:39:20 -0800

> From: Eric Dumazet <edumazet@...gle.com>
> 
> For tests that are using the maximal number of BPF instruction, each
> run takes 20 usec. Looping 10,000 times on them totals 200 ms, which
> is bad when the loop is not preemptible.
> 
> test_bpf: #264 BPF_MAXINSNS: Call heavy transformations jited:1 19248
> 18548 PASS
> test_bpf: #269 BPF_MAXINSNS: ld_abs+get_processor_id jited:1 20896 PASS
> 
> Lets divide by ten the number of iterations, so that max latency is
> 20ms. We could use need_resched() to break the loop earlier if we
> believe 20 ms is too much.
> 
> Signed-off-by: Eric Dumazet <edumazet@...gle.com>

Acked-by: David S. Miller <davem@...emloft.net>