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=-20.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,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 447FEC433B4 for ; Thu, 13 May 2021 13:19:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0C16E61433 for ; Thu, 13 May 2021 13:19:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233951AbhEMNUI (ORCPT ); Thu, 13 May 2021 09:20:08 -0400 Received: from Galois.linutronix.de ([193.142.43.55]:58520 "EHLO galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233918AbhEMNSk (ORCPT ); Thu, 13 May 2021 09:18:40 -0400 Date: Thu, 13 May 2021 13:17:28 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1620911848; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=HMwn8O3nBoPuE7nUlO7ip7NNJF+oVD6bUgbDrgpjT/k=; b=fffC+ZHsPvoZ9liHabQWAGOFafd4nYsA+4Wo58hGHVVuiuoxnWkCYTUXpeskHcsyzJATdS gsebEQx/pkWISj0JLZrEcOd6ocJgflYJJNbG4g6A2huHssMa3jvNCraeJ7OCS56rYy2hAy eAB9hZn/HwY/w5k1rwxIS/6kXrVthjeAcUqg9JDMbpRpGv84+DSTVRQhdKXn7ZjpcN4Esz SinjI6b7TK3px9/uyThILAc2t3BgMh6YwrE6rLCbojvolG55K5Sbxn+RvIcj9rLVR/r3A6 t288tnq2JDgKNHCEVPSypxVlIqm1z5tzUTqB8DUXwR75Ac3LkG2IRHUgmTZSkg== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1620911848; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=HMwn8O3nBoPuE7nUlO7ip7NNJF+oVD6bUgbDrgpjT/k=; b=nfXvMgKT1kDn922NkeqFo6E1GBO11sCCwV8fLYwM0YguZNvVH3C7l+u6QlrC4AdKGdFpjN s5dQhqNuGln0JNBg== From: "tip-bot2 for Frederic Weisbecker" Sender: tip-bot2@linutronix.de Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: timers/nohz] tick/nohz: Update nohz_full Kconfig help Cc: Frederic Weisbecker , Ingo Molnar , Peter Zijlstra , x86@kernel.org, linux-kernel@vger.kernel.org In-Reply-To: <20210512232924.150322-6-frederic@kernel.org> References: <20210512232924.150322-6-frederic@kernel.org> MIME-Version: 1.0 Message-ID: <162091184822.29796.1242283230683760221.tip-bot2@tip-bot2> Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The following commit has been merged into the timers/nohz branch of tip: Commit-ID: 176b8906c399a170886ea4bad5b24763c6713d61 Gitweb: https://git.kernel.org/tip/176b8906c399a170886ea4bad5b24763c6713d61 Author: Frederic Weisbecker AuthorDate: Thu, 13 May 2021 01:29:19 +02:00 Committer: Ingo Molnar CommitterDate: Thu, 13 May 2021 14:21:21 +02:00 tick/nohz: Update nohz_full Kconfig help CONFIG_NO_HZ_FULL behaves just like CONFIG_NO_HZ_IDLE by default. Reassure distros about it. Signed-off-by: Frederic Weisbecker Signed-off-by: Ingo Molnar Acked-by: Peter Zijlstra Link: https://lore.kernel.org/r/20210512232924.150322-6-frederic@kernel.org --- kernel/time/Kconfig | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/kernel/time/Kconfig b/kernel/time/Kconfig index 83e158d..7df71ef 100644 --- a/kernel/time/Kconfig +++ b/kernel/time/Kconfig @@ -117,13 +117,14 @@ config NO_HZ_FULL the task mostly runs in userspace and has few kernel activity. You need to fill up the nohz_full boot parameter with the - desired range of dynticks CPUs. + desired range of dynticks CPUs to use it. This is implemented at + the expense of some overhead in user <-> kernel transitions: + syscalls, exceptions and interrupts. - This is implemented at the expense of some overhead in user <-> kernel - transitions: syscalls, exceptions and interrupts. Even when it's - dynamically off. + By default, without passing the nohz_full parameter, this behaves just + like NO_HZ_IDLE. - Say N. + If you're a distro say Y. endchoice