From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-qt1-f181.google.com (mail-qt1-f181.google.com [209.85.160.181]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0F54F14AD04; Fri, 23 Feb 2024 21:44:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.160.181 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1708724663; cv=none; b=ZDOsSd3iUkiA5t/xrSbTv4jh3YAju6gtOgsNcSuQWFl5EiUkmIkT08nRUxoGIpp1Z2Z8aX84t5cIarAJl7dCTKxepsv5x/3Z3lcSwdTyGgIgbV1fBWszU842LlMWCh9XvsgflB28u1qpZ3VurZZzFyDzJNmHvfsP9qlOK8QjTR0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1708724663; c=relaxed/simple; bh=Pe5erZHyCvS6VkWlhzfR04p/Sev+tZt7VSqDg3j4P8Q=; h=MIME-Version:References:In-Reply-To:From:Date:Message-ID:Subject: To:Cc:Content-Type; b=SLqWKOwGeqShL6Gl+QfKdFkgdP3XpdKm6DXfTGDJvBDts0VdRztg2yq+DjQSj9UDbvCjglWLOxppja/8KP4GxIUlefhoOVkxZ3s+JgPuU1TcQxRYaDDJSrMU52y4AqMWG7Lefd+LNqdxf2whRAEUOB66zaOToYhKs2yVNRar0W4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=ocallahan.org; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail-com.20230601.gappssmtp.com header.i=@gmail-com.20230601.gappssmtp.com header.b=yPUj50H3; arc=none smtp.client-ip=209.85.160.181 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=ocallahan.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail-com.20230601.gappssmtp.com header.i=@gmail-com.20230601.gappssmtp.com header.b="yPUj50H3" Received: by mail-qt1-f181.google.com with SMTP id d75a77b69052e-42a9f4935a6so6190461cf.1; Fri, 23 Feb 2024 13:44:20 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail-com.20230601.gappssmtp.com; s=20230601; t=1708724660; x=1709329460; darn=vger.kernel.org; h=cc:to:subject:message-id:date:from:reply-to:in-reply-to:references :mime-version:from:to:cc:subject:date:message-id:reply-to; bh=dflXWGJiHy7MbSy8pXkZb9NeeYUWtRBjyhK7A4GkIig=; b=yPUj50H34+iXkWP9ZoINgCfeRvzn6tJnjokRnGWvxpxq64M8AbuGVzv6z1C8niRJkc x8Wag+5AsU6w0Rhza3+xw0leWKf5t5FcfMPe1drtcgssIr6Jn+sVSAm8B5iWiMbZNmFw Ad9pFgJOzPRgXam5QpgajJz9PoKeDRSraS4lPweW3+70wUaYQaifg4xcmHV4qgyJ5uzf wDNIaUS57t4Le+KrJ+vaXlWNQokkXzZsn58aGSm8HyiBEIjYs+KD/qQGJ70cFvStel1Y t6JF9XB0CWbI0CvmQ6nBO9AV93rqcd8Xz/bJSwgNLZ0YWucR8bHz96ZXvkAkJ9O1RJ8t icww== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1708724660; x=1709329460; h=cc:to:subject:message-id:date:from:reply-to:in-reply-to:references :mime-version:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=dflXWGJiHy7MbSy8pXkZb9NeeYUWtRBjyhK7A4GkIig=; b=TeqAYOZHOStIQzU1EE7I2PxG95XCvb/jVwDV4RgxktTfTirlR0WxSacdSwNuQ+u/t6 KS6tuhLJxBNO4fgmNKVS/BrH6WCmG+/fYMQ2QdSxDoijAvi/8ncxIYE4ISonlGVm21/m Igj++AQONZ3OzWAa2njnNY0+uXKjGJaznBaTp4EdLCTlQYdacZqICefIKzcvJWWzn718 dEQZ/yWJlU7lxN7Xg+EmHgu8g2Is7wmepS3GIrWjVEY7HLlImNx7KRf0aeQ7/clduyUl F2ef7hfkEtxTQS8YKE2L/Sf62QnRAVAqXCqoRq13lYX5NeO3SfnGC6j+v5o1XNeTioiW +UTA== X-Forwarded-Encrypted: i=1; AJvYcCVUPULJpGqeK0ofqwPdo6FvBte1Z2HFgAxoUvU98NiuW8ubsn8p+ER2b886djN7dbxH6Oy+lmTmSIavLCtdsHLifNtsos0cEc/58FA/wXwj/ZqKubFHh5ETNmg0zdks5r5Z/eKNAQR88Neisg4YAQ== X-Gm-Message-State: AOJu0YyScr9VITtFLPGSOKOZO6fymQUHNPo/9yliQ0+ba5+RfPXU/4Uj 52d3x+0jzhc3OJZ3gWL94jpWmsC3yBkI4wueNpw7OjfZKZy8vU38CDAOmu9HM0A1Mnfkgyo8Bf4 5ji2CGuFTxBPvmMHKTXrQTWA7eDY= X-Google-Smtp-Source: AGHT+IEdqbE3nTHzTHVnvtCEoIC2+Cn09Y4dZAXa8zWYlw3yYVCckBoDOV8siFuX1rqxLf21t2FTt18kB0pJV1s+ch4= X-Received: by 2002:ac8:7dca:0:b0:42d:de30:83e1 with SMTP id c10-20020ac87dca000000b0042dde3083e1mr694373qte.29.1708724659935; Fri, 23 Feb 2024 13:44:19 -0800 (PST) Precedence: bulk X-Mailing-List: linux-perf-users@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 References: <20240221175210.19936-1-khuey@kylehuey.com> <20240221175210.19936-2-khuey@kylehuey.com> In-Reply-To: Reply-To: robert@ocallahan.org From: "Robert O'Callahan" Date: Sat, 24 Feb 2024 10:43:38 +1300 Message-ID: Subject: Re: [PATCH 2/2] perf test: Test FASYNC with watermark wakeups. To: Arnaldo Carvalho de Melo Cc: Kyle Huey , Ian Rogers , Kyle Huey , Peter Zijlstra , Ingo Molnar , Namhyung Kim , Mark Rutland , Alexander Shishkin , Jiri Olsa , Adrian Hunter , linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" (I work with Kyle.) IMHO this is more of a bug fix than a feature. `man perf_event_open` expects this to work already: "watermark: If set, have an overflow notification happen when we cross the wakeup_watermark boundary" and later "Alternatively, the overflow events can be captured via a signal handler, by enabling I/O signaling". Bug fixes need regression tests. Such tests should fail on any kernel where the bug is present. It seems strange to expect each such test to detect whether the bug "should be fixed" in the kernel it's running on and skip when that's not the case. I haven't seen any other project try to do this. Instead (as in kernel selftests) the tests, the code under test, and any metadata about which tests are expected to pass are all in the repository together and updated together. It makes sense that tests for the code in tools/perf should not fail on older kernels, given that the code in tools/perf is expected to work on older kernels. But tests for bug fixes in the kernel itself should be expected to fail on older kernels and therefore should live somewhere else, IMHO. Rob -- Su ot deraeppa sah dna Rehtaf eht htiw saw hcihw, efil lanrete eht uoy ot mialcorp ew dna, ti ot yfitset dna ti nees evah ew; deraeppa efil eht. Efil fo Drow eht gninrecnoc mialcorp ew siht - dehcuot evah sdnah ruo dna ta dekool evah ew hcihw, seye ruo htiw nees evah ew hcihw, draeh evah ew hcihw, gninnigeb eht morf saw hcihw taht.