From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CC2D224BBFD for ; Fri, 2 May 2025 12:31:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=193.142.43.55 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746189098; cv=none; b=bFt7lS8av7d2eIwFn8Ik3sDQAiTOBmsLUBfooPgwjvPHiRPHf7YQUhR5p9+Gc1hEFsVi4lAvJRHuz8Hi9j5yHuKwROSLVMN0iyGWVv4/naAyDhiE6ej2lWATWn8p5VbrOwfZdcYRXjUbBZutBXcfbGJqA5BDxhoiy1y1TLms6lM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746189098; c=relaxed/simple; bh=XesEG/0KvQlQV0UEHbw2alP/dDBhq3XhIOw7ALm9CfU=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=tkjlwHB1XKXAM4654kXZXzy0jzzL0N3hy5CAp93fzcm4Kbxoo4erBTtbZd2d3ss/vVMP07Xec+6ObYUnvf3i/eDokm1GNBWeveiyFpUARUdKuW1KOSmJaVxHmISKPDcrUX7D1jZBQGikcF3MR8iO+0PXSTO0/Uia3W4ynXQUs+Y= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de; spf=pass smtp.mailfrom=linutronix.de; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=dZzgyc/J; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=/3To1Us1; arc=none smtp.client-ip=193.142.43.55 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linutronix.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="dZzgyc/J"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="/3To1Us1" Date: Fri, 2 May 2025 14:31:33 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1746189094; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=l/ps/KnLOGHL6+wgjhHsQWYaOPZoEkEqnfArzWRawig=; b=dZzgyc/Jx4pWYVxAI3jk4myI0wWutMBehsuMmDUNViApCehaoM0VEYBgJl8Xt+Y6/wqgbi cRpMWV6mJcYuBZiVh+BVD3IEAfzUmQO2uypHhAMmPBBe/m92/+gV7KbkqslV3xLpGJaEyK Hm4UBOvOtn1t8hl+KyOr5vSnk1SLLGwzs7qIaKWuMC9QQu4d4z0XmurB62vEttzbYBMLu/ YWVFiACC4p1x74av46EyOgSYW3X1rNyxN8Jn7tCpCZCJt6lELcJzU9UsOeg0xzw1Ck1iaO 5fVljhJzK8pYHkg0lao1WWECRdywmVrlf6MTi1qX+GvgvSERzi3OzgrbYU3DDQ== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1746189094; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=l/ps/KnLOGHL6+wgjhHsQWYaOPZoEkEqnfArzWRawig=; b=/3To1Us1j6sBLnH+ixHLadDwWm+zG6mFH/XSbv0ikWEFKfqr/yvf+BxsH3lKix1aw4ubxT 9ldnHOGlM5lVVRDw== From: Sebastian Andrzej Siewior To: Peter Zijlstra Cc: Prakash Sangappa , linux-kernel@vger.kernel.org, rostedt@goodmis.org, mathieu.desnoyers@efficios.com, tglx@linutronix.de, kprateek.nayak@amd.com Subject: Re: [PATCH V3 4/4] Sched: Add tracepoint for sched time slice extension Message-ID: <20250502123133.4pGihD-W@linutronix.de> References: <20250502015955.3146733-1-prakash.sangappa@oracle.com> <20250502015955.3146733-5-prakash.sangappa@oracle.com> <20250502091434.GV4198@noisy.programming.kicks-ass.net> <20250502110210.rZX1iHcg@linutronix.de> <20250502111044.GY4198@noisy.programming.kicks-ass.net> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20250502111044.GY4198@noisy.programming.kicks-ass.net> On 2025-05-02 13:10:44 [+0200], Peter Zijlstra wrote: > On Fri, May 02, 2025 at 01:02:10PM +0200, Sebastian Andrzej Siewior wrote: > > On 2025-05-02 11:14:34 [+0200], Peter Zijlstra wrote: > > > This is horrific coding style. But really why do we need this? I'm not, > > > in general, a fan of tracepoints. > > > > I suggested a tracepoint so that we see why the NEED_RESCHED flag > > disappeared. The trace would show a wakeup, the need_resched flag would > > be set and the flag would disappear without an explanation. > > Would we not see a timer_start event for the hrtick or somesuch? Yes, we do. That would mean we need timer:hrtimer* in order for the sched:* to make sense. Sebastian