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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id AD8A4C4167B for ; Wed, 6 Dec 2023 09:24:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346778AbjLFJYp (ORCPT ); Wed, 6 Dec 2023 04:24:45 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37770 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1346728AbjLFJYn (ORCPT ); Wed, 6 Dec 2023 04:24:43 -0500 Received: from galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 07F77D49 for ; Wed, 6 Dec 2023 01:24:48 -0800 (PST) From: Anna-Maria Behnsen DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1701854686; 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=93v4gttHfsOj4z7ueaDWrNz1D5HKd3pZTasSdZAFavo=; b=v209QlOlMT9g82bMBVx7adDQvqsF6KeALigEAbFmYNlflxkBRwMeEljUW8D39KRfA2nrkG BY7ExinGmsxF0bX5AZCPxCh072aDnzUEztBs0tLWUNof2arEHm6i6fV4enA81n74+JusXe qJ6Z8hh+fYe/rZA658f8Xm/3m+LnxvYqZdDxc9ggTRZwd4WmIiCtSLKJgkPZleHWtV4qua px2YiPT+unZ2u4d4Zvf/NNSeGIAZ9EHIAn3wfuuXI5lzAYJagTUZpFbt/+UF7f/Q2PBHtX uY1O722r5MMGInTm9N94lrnSE6c0KQbiLceviFnKG7nKHmq1yFgIzW9J8rwYfA== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1701854686; 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=93v4gttHfsOj4z7ueaDWrNz1D5HKd3pZTasSdZAFavo=; b=r7SKlq9CJN8pk20mL/YsZXgad23ibFNr9vRc0T7/dZrfYqAEvM21rwHYg42JOepCCxUrFQ HacYlD2hWkIac6AA== To: Sebastian Siewior Cc: linux-kernel@vger.kernel.org, Peter Zijlstra , John Stultz , Thomas Gleixner , Eric Dumazet , "Rafael J . Wysocki" , Arjan van de Ven , "Paul E . McKenney" , Frederic Weisbecker , Rik van Riel , Steven Rostedt , Giovanni Gherdovich , Lukasz Luba , "Gautham R . Shenoy" , Srinivas Pandruvada , K Prateek Nayak Subject: Re: [PATCH v9 17/32] timers: Introduce add_timer() variants which modify timer flags In-Reply-To: <20231205182835.DNCNokiI@linutronix.de> References: <20231201092654.34614-1-anna-maria@linutronix.de> <20231201092654.34614-18-anna-maria@linutronix.de> <20231205182835.DNCNokiI@linutronix.de> Date: Wed, 06 Dec 2023 10:24:45 +0100 Message-ID: <87r0jzel9e.fsf@somnus> MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Sebastian Siewior writes: > On 2023-12-01 10:26:39 [+0100], Anna-Maria Behnsen wrote: >> Timer might be used as pinned timer (using add_timer_on()) and later on as >> non pinned timers using add_timer(). When the NOHZ timer pull at expiry >> model is in place, TIMER_PINNED flag is required to be used whenever a >> timer needs to expire on a dedicated CPU. Flag must no be set, if >> expiration on a dedicated CPU is not required. > > Slightly reworded. > > | A timer might be used as a pinned timer (using add_timer_on()) and later > | on as non-pinned timer using add_timer(). When the "NOHZ timer pull at > | expiry model" is in place, the TIMER_PINNED flag is required to be used > | whenever a timer needs to expire on a dedicated CPU. Otherwise the flag > | must not be set if expiration on a dedicated CPU is not required. > >> add_timer_on()'s behavior will be changed during the preparation patches >> for the NOHZ timer pull at expiry model to unconditionally set TIMER_PINNED >> flag. To be able to reset/set the flag when queueing a timer, two variants >> of add_timer() are introduced. > > and here. > > | add_timer_on()'s behavior will be changed during the preparation patches > | for the "NOHZ timer pull at expiry model" to unconditionally set > | TIMER_PINNED flag. To be able to clear/ set the flag when queueing a > | timer, two variants of add_timer() are introduced. > > I let you be judge of this. I will take your reworded version. Thanks, Anna-Maria