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 Received: from picard.linux.it (picard.linux.it [213.254.12.146]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id A674EC4345F for ; Wed, 24 Apr 2024 12:22:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=lists.linux.it; i=@lists.linux.it; q=dns/txt; s=picard; t=1713961369; h=date : mime-version : message-id : to : subject : list-id : list-unsubscribe : list-archive : list-post : list-help : list-subscribe : from : reply-to : cc : content-type : content-transfer-encoding : sender : from; bh=nqaagS2Wl3i9yM93JcdIxbMSzaq/BE2s6+49mFb1TKA=; b=jWXewYAszeK2cef3RXaFEhM8k6eWwpOmSTvzY/F3D6JhALetYMYzxdcQHxkJZqbZnv/J9 CbUiFTxdTu1zUwhlbTDb5oo8FDCj1jaXrlMc6L9HF8sdIvURMzlw9YBuI23h8WZGHNlfwpT Iaetywqf0yxKQlJ13X+SKKd1KT0oyZU= Received: from picard.linux.it (localhost [IPv6:::1]) by picard.linux.it (Postfix) with ESMTP id 293CC3D0036 for ; Wed, 24 Apr 2024 14:22:49 +0200 (CEST) Received: from in-7.smtp.seeweb.it (in-7.smtp.seeweb.it [IPv6:2001:4b78:1:20::7]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (secp384r1)) (No client certificate requested) by picard.linux.it (Postfix) with ESMTPS id 516823CFA6F for ; Wed, 24 Apr 2024 00:58:28 +0200 (CEST) Received: from mail-pl1-x649.google.com (mail-pl1-x649.google.com [IPv6:2607:f8b0:4864:20::649]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by in-7.smtp.seeweb.it (Postfix) with ESMTPS id 555502005D6 for ; Wed, 24 Apr 2024 00:58:28 +0200 (CEST) Received: by mail-pl1-x649.google.com with SMTP id d9443c01a7336-1e3c2fbc920so2185335ad.0 for ; Tue, 23 Apr 2024 15:58:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1713913107; x=1714517907; darn=lists.linux.it; h=cc:to:from:subject:message-id:mime-version:date:from:to:cc:subject :date:message-id:reply-to; bh=IBcDGjWKXokMjPsghOEAM9h/qxapVnoPg0MA16oLO+A=; b=fGRig12TDn62WF8GwQNjClz6Bb/oEK4EDXKeyqYnvUZXR3tZiy7X/+ZaLn7/oVrkRQ hsUGUqiq5ecFfuZCLQOTjitvEMM8D4A+Mvkvl4xe/5hA4wgJ1W34c5QQMHSrlwtjy5T9 183og2eTFdInnokY6I891I65FbTgcRYapmrTssJszzq9S4OTGbDPOW7HgOn9GTe6OSGk 0iYs8vUzj71bRY+fS708DH1TW+1GZ2tYK1kVjrWMpLipWOU5i36a7HphkLAmFUsV+nia m6J6RhcGMcCtJodIG2IT9gZNWcqiAShFl01Pbu0kMWJkYiNG+tsg4BFYNArkAMIio9Ei 4BzA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1713913107; x=1714517907; h=cc:to:from:subject:message-id:mime-version:date:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=IBcDGjWKXokMjPsghOEAM9h/qxapVnoPg0MA16oLO+A=; b=paHNSdQxIkydpH13wMueXf2Bkrd3h2cYv8d7mK/ottkr6wO5FDDz4ALqzlpXm48d3g LH/0axYPdbgKjoKOqk7d3zqtdwClzZvocUZGraPJMziWDgn2SuExGU8p20sTUg2P+e7n B3Aqv737c+toVuhz/F2xVCQfDuqa3W4Qi+wMTmBC3GhI3iDKQN5x+5FK/jUaUbR2CL0H npOHex3NFEVJiuHTkm7huK8wGJd2RF+hCX8IiVwz5gM7KWPGzALkkqBDhUp12I5F6J9F CjKbBpnShVg5XXxpZX/QetL0c1659lhJmLyBjrl4q2198mY9PlgxK1nJx1yojFc3AzME Df1Q== X-Gm-Message-State: AOJu0Yz5Y/FKpU3wH4DTiMHUt6uZGlj3raWhe5OC16UA2PnrXD9knQoo ClKLqrzjVOHM/Bkf9Q9j0XF09fd+aFly+6aPX0Lkp++XgDC5lOxPWVw8YkMLvAExtY638IsCY9J krlMUyOBlLlqK1QBIYARCIbitBGlFabSvrMAfLkX6DfZFE29Isxv9a3X2oJarKiMOUktVAPVLuu jrZBJOBXSwm4XkB4d+Fw+ldqyF1UxCVm4= X-Google-Smtp-Source: AGHT+IGpKjKTJQ2Ews2jKk4AIIorRKEpX8URIejrQPEyhkajXBx19wSSI4rf/7riRetx590XxJkNWVi1/DH1 X-Received: from jstultz-noogler2.c.googlers.com ([fda3:e722:ac3:cc00:24:72f4:c0a8:600]) (user=jstultz job=sendgmr) by 2002:a17:902:8486:b0:1e5:56e8:7bbd with SMTP id c6-20020a170902848600b001e556e87bbdmr14288plo.1.1713913106142; Tue, 23 Apr 2024 15:58:26 -0700 (PDT) Date: Tue, 23 Apr 2024 15:57:57 -0700 Mime-Version: 1.0 X-Mailer: git-send-email 2.44.0.769.g3c40516874-goog Message-ID: <20240423225821.4003538-1-jstultz@google.com> To: ltp@lists.linux.it X-Virus-Scanned: clamav-milter 1.0.3 at in-7.smtp.seeweb.it X-Virus-Status: Clean X-Mailman-Approved-At: Wed, 24 Apr 2024 14:22:03 +0200 Subject: [LTP] [PATCH 0/6] sched_football: Re-add crazy fans and other cleanups X-BeenThere: ltp@lists.linux.it X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux Test Project List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , From: John Stultz via ltp Reply-To: John Stultz Cc: kernel-team@android.com, John Stultz , Darren Hart Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: ltp-bounces+ltp=archiver.kernel.org@lists.linux.it Sender: "ltp" Just the other day (~18 years ago), I had implemented the sched_football test to validate the RT scheduling invariant that we always run the top NR_CPU priority tasks at any time. That early version of the test included crazy fans, which disrupted the scheduling of the defensive threads. This was later removed from the test, likely due to occasional failures seen with it. Recently, in testing the behavior of a scheduler patch I was working on I started tinkering with this test again, and found when I re-added the crazy fans, I could reproduce an actual scheduling problem with the vanilla kernel. So I wanted to submit these changes to re-add the crazy fans along with some other cleanups and improvements to make it easier to use with tracing, so that the test can be used by others to reproduce this problem. Feedback would be appreciated! thanks -john Cc: kernel-team@android.com Cc: Darren Hart John Stultz (6): sched_football: Drop use of sched_yeild() sched_football: Use atomic for ball sched_football: Re-add the crazy fans to interrupt everyone sched_football: Add a sleep before the game begins to get into steady state sched_football: Add prctrl calls to set thread comms sched_football: Add trace_marker messages if we're tracing .../func/sched_football/sched_football.c | 94 +++++++++++++++---- 1 file changed, 78 insertions(+), 16 deletions(-) -- 2.44.0.769.g3c40516874-goog -- Mailing list info: https://lists.linux.it/listinfo/ltp