From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1EDAAC4CECE for ; Fri, 13 Mar 2020 06:45:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EA43C20749 for ; Fri, 13 Mar 2020 06:45:27 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="mjEKyd/s" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726001AbgCMGp1 (ORCPT ); Fri, 13 Mar 2020 02:45:27 -0400 Received: from mail-pg1-f194.google.com ([209.85.215.194]:42315 "EHLO mail-pg1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726314AbgCMGp1 (ORCPT ); Fri, 13 Mar 2020 02:45:27 -0400 Received: by mail-pg1-f194.google.com with SMTP id h8so4405133pgs.9; Thu, 12 Mar 2020 23:45:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=WPL3gUJrRKM2cbWWfIBmuWTyQv5A63MVH3jx8qJd4P8=; b=mjEKyd/sdH949lL+MIiRiMVBQxWxwK5iyMcdEk8tyUd40X0Dzh0iKBUB8lxuWsqaTc 0l0ozuIUIt8XnD6zfnFR2aRiIRV9Ko3/K6pRIrSe+j8omma9FM/xGvhEFMcefI8m854W 9BkHwHyVVenQwEeYw34EiGyW4DZbk82R1iSmdWmimkqaCoShmredoIVnAqld35dKWmJY sDSuGoiK0K+ABHPMn6rmwP/HDLddIm8rR1m3wKtIIjkBwZU0e/1qvlnhs7CpOnEG3foo hUExpzHgMTQszVJHHCiz1w0i4BkrdlCvy4TG72uZkBNBJYUnU6PZhfQcTxQ2ur4hN5tR Rtcw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=WPL3gUJrRKM2cbWWfIBmuWTyQv5A63MVH3jx8qJd4P8=; b=J1YA1/TUsHrS9UhN3rNDnfXEWS/ds6AENbHpSwhqdLJoCiMVBixTdGIgf1Rk7byNb4 TBOGVUnmmEEl/7GqmZ3o0DhgjpiGZFDYnIGyMwGQbZXhQaowVwmdCCoEQs6RMdckB6Td wQkMUOa9gsDRxyjangVhQjlJ4q/Sh3ovqg7E873Q6h7wHtVjt86W7vlYUK+RPxuh1LQn s5nwCoE29kwMQloZFM5+NMsnTD0X7qESbKHBXdu0FrJFXI0ofzj8sDGfQwwwFY4XvfNL Be8UXeIJ/O1kCaO3I1/wmRnUaJUH++qfmF1E/OLyJ65xRXwsFljStYkihGn1JPLSJ/UC 3N/Q== X-Gm-Message-State: ANhLgQ3G/8MyNmZ7f1z7IvL7339moGhR8gEoiz70YzMSO5+5v541o56Y 71zvpkTCTgvULF2OEIdyJYc= X-Google-Smtp-Source: ADFU+vtdwSnIwGDkvJIX39nEet2iV8W2aSU5f/YqKOuadfd8aCC6VJ2S5ob98QKACgVeNVTms1f3MQ== X-Received: by 2002:aa7:8bd1:: with SMTP id s17mr12079026pfd.225.1584081924569; Thu, 12 Mar 2020 23:45:24 -0700 (PDT) Received: from ast-mbp ([2620:10d:c090:400::5:d19a]) by smtp.gmail.com with ESMTPSA id o129sm3851681pfb.61.2020.03.12.23.45.22 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 12 Mar 2020 23:45:23 -0700 (PDT) Date: Thu, 12 Mar 2020 23:45:21 -0700 From: Alexei Starovoitov To: Andrii Nakryiko Cc: bpf@vger.kernel.org, netdev@vger.kernel.org, ast@fb.com, daniel@iogearbox.net, andrii.nakryiko@gmail.com, kernel-team@fb.com Subject: Re: [PATCH bpf-next] selftests/bpf: fix usleep() implementation Message-ID: <20200313064521.se2sqpgkpd5ekmfo@ast-mbp> References: <20200313061837.3685572-1-andriin@fb.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200313061837.3685572-1-andriin@fb.com> Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org On Thu, Mar 12, 2020 at 11:18:37PM -0700, Andrii Nakryiko wrote: > nanosleep syscall expects pointer to struct timespec, not nanoseconds > directly. Current implementation fulfills its purpose of invoking nanosleep > syscall, but doesn't really provide sleeping capabilities, which can cause > flakiness for tests relying on usleep() to wait for something. > > Fixes: ec12a57b822c ("selftests/bpf: Guarantee that useep() calls nanosleep() syscall") > Signed-off-by: Andrii Nakryiko > --- > tools/testing/selftests/bpf/test_progs.c | 11 ++++++++++- > 1 file changed, 10 insertions(+), 1 deletion(-) > > diff --git a/tools/testing/selftests/bpf/test_progs.c b/tools/testing/selftests/bpf/test_progs.c > index 2b0bc1171c9c..b6201dd82edf 100644 > --- a/tools/testing/selftests/bpf/test_progs.c > +++ b/tools/testing/selftests/bpf/test_progs.c > @@ -35,7 +35,16 @@ struct prog_test_def { > */ > int usleep(useconds_t usec) > { > - return syscall(__NR_nanosleep, usec * 1000UL); > + struct timespec ts; > + > + if (usec > 999999) { > + ts.tv_sec = usec / 1000000; > + ts.tv_nsec = usec % 1000000; > + } else { > + ts.tv_sec = 0; > + ts.tv_nsec = usec; > + } > + return nanosleep(&ts, NULL); > } Is this a copy-paste from somewhere? Above 'if' looks like premature optimization. I applied it anyway, since it fixes flakiness in test_progs -n 24. Now pin*tp* tests are stable. But the other one is still flaky: server_thread:FAIL:237 Failed to accept client: Resource temporarily unavailable #64 tcp_rtt:FAIL Note that if I run the test alone (test_progs -n 64) it is stable. It fails only when run as part of bigger test_progs. test_progs -n 30-64 sporadically fails (most of the time) test_progs -n 40-64 consistently passes Haven't bisected further.