From nobody Tue Feb 10 02:43:43 2026 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 8DE8CC77B7A for ; Wed, 24 May 2023 07:08:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239971AbjEXHIU (ORCPT ); Wed, 24 May 2023 03:08:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47966 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239908AbjEXHHj (ORCPT ); Wed, 24 May 2023 03:07:39 -0400 Received: from galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 50C431B4 for ; Wed, 24 May 2023 00:07:06 -0700 (PDT) From: Anna-Maria Behnsen DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1684912024; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=5Rgz0XMpFHBcgryFLb9u8XHoyQkZQCERFRJm4RJQ5aM=; b=ZA/565hYULTzhp4Plywb8Bb+rNQozqthRlQ6lyBZEoVflXtTSl3KMZujNEkfx0dSNcU5/7 trLT0/nXE2rKYK6Cizc0bIhdbBXM44Qg9RlA3fFF0fgq6Vg2HKXAKhkbjZqkf0kruE5vZO nieSIsftVRLVWSu9ja7vlz+8Lbz13x96ybGfJQ4LhtyKs8McVBIfgEj34JufyUpUZ3n3/Q 8Gq8jjCogehMm6wwEdK3YSpTVigv7G4MRAwOBI97dFp9GDoRQvYuylShzLYDRBvp1Lanrf 3NFUmpc85EyY6G9KcUr2YW+U4rnL4i9lHp9GGV0Uqf6oTE9SLjYjbhw44w04iQ== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1684912024; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=5Rgz0XMpFHBcgryFLb9u8XHoyQkZQCERFRJm4RJQ5aM=; b=B10AAADYkHpwVbWkLSNQvdrPRmrH7RAgbM7qllpRuQNJyuypUowUeOG9RoOUqqsfBCeaUt k5vfawz1UXqFJcCA== To: linux-kernel@vger.kernel.org Cc: 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 , Sebastian Siewior , Giovanni Gherdovich , Lukasz Luba , "Gautham R . Shenoy" , "Richard Cochran (linutronix GmbH)" , Anna-Maria Behnsen Subject: [PATCH v7 16/21] timer: Restructure internal locking Date: Wed, 24 May 2023 09:06:24 +0200 Message-Id: <20230524070629.6377-17-anna-maria@linutronix.de> In-Reply-To: <20230524070629.6377-1-anna-maria@linutronix.de> References: <20230524070629.6377-1-anna-maria@linutronix.de> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: "Richard Cochran (linutronix GmbH)" Move the locking out from __run_timers() to the call sites, so the protected section can be extended at the call site. Preparatory patch for changing the NOHZ timer placement to a pull at expiry time model. No functional change. Signed-off-by: Richard Cochran (linutronix GmbH) Signed-off-by: Anna-Maria Behnsen --- kernel/time/timer.c | 31 +++++++++++++++++++++---------- 1 file changed, 21 insertions(+), 10 deletions(-) diff --git a/kernel/time/timer.c b/kernel/time/timer.c index 564001b98098..20106dad531a 100644 --- a/kernel/time/timer.c +++ b/kernel/time/timer.c @@ -2202,11 +2202,7 @@ static inline void __run_timers(struct timer_base *b= ase) struct hlist_head heads[LVL_DEPTH]; int levels; =20 - if (time_before(jiffies, base->next_expiry)) - return; - - timer_base_lock_expiry(base); - raw_spin_lock_irq(&base->lock); + lockdep_assert_held(&base->lock); =20 while (time_after_eq(jiffies, base->clk) && time_after_eq(jiffies, base->next_expiry)) { @@ -2226,21 +2222,36 @@ static inline void __run_timers(struct timer_base *= base) while (levels--) expire_timers(base, heads + levels); } +} + +static void __run_timer_base(struct timer_base *base) +{ + if (time_before(jiffies, base->next_expiry)) + return; + + timer_base_lock_expiry(base); + raw_spin_lock_irq(&base->lock); + __run_timers(base); raw_spin_unlock_irq(&base->lock); timer_base_unlock_expiry(base); } =20 +static void run_timer_base(int index) +{ + struct timer_base *base =3D this_cpu_ptr(&timer_bases[index]); + + __run_timer_base(base); +} + /* * This function runs timers and the timer-tq in bottom half context. */ static __latent_entropy void run_timer_softirq(struct softirq_action *h) { - struct timer_base *base =3D this_cpu_ptr(&timer_bases[BASE_LOCAL]); - - __run_timers(base); + run_timer_base(BASE_LOCAL); if (IS_ENABLED(CONFIG_NO_HZ_COMMON)) { - __run_timers(this_cpu_ptr(&timer_bases[BASE_GLOBAL])); - __run_timers(this_cpu_ptr(&timer_bases[BASE_DEF])); + run_timer_base(BASE_GLOBAL); + run_timer_base(BASE_DEF); } } =20 --=20 2.30.2