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 E1B4DC4332F for ; Fri, 4 Nov 2022 14:59:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232364AbiKDO7I (ORCPT ); Fri, 4 Nov 2022 10:59:08 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41710 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232248AbiKDO6F (ORCPT ); Fri, 4 Nov 2022 10:58:05 -0400 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EBBA7317EF for ; Fri, 4 Nov 2022 07:57:59 -0700 (PDT) From: Anna-Maria Behnsen DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1667573878; 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=bR/mftSP+c00ARZaKpp17SnhKoPd5BhUk3++d2T/vCA=; b=pfuMn0tB4XvaXaxjLKLEA7eLNd19BHMNYFkZjtkLMrL7U7qZpJ83I0x0iTzN3ophyHF8sK Y32iIHbmCxJ1zUzVhUOSmjwBCkoQkZWAWRiWNtCNuFOwc87yYDPC9c2WKbRcJzCuQFAnDE bDvh8mrUjJh9ypeXTE4GI87WhQm4k3lDk4zoQ4Mt+O8HUmVeKOEhromVWuQgTZZLoJGX89 1xXA52iEzuMXsBI5QPEmLCYdaFgGwqxC5rAZzaZzSFFRIC6gsfsqq6zbzVZ37Gag5W2wgh 5r5qUzbw15jPZL5GYCRUHcSKzaRvb8FL7i5f0tlrmL82hM+/qv2bzMJc6L5k/Q== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1667573878; 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=bR/mftSP+c00ARZaKpp17SnhKoPd5BhUk3++d2T/vCA=; b=9FEpIwyJCazovQUC5fZa2Ev4q0i98lV3OV5rm+y2sgZ/wTepYpgtZsSEbEaPEIZQvzmlHt O4Yo32UnlmCSnPBw== 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 , "Richard Cochran (linutronix GmbH)" , Anna-Maria Behnsen Subject: [PATCH v4 11/16] timer: Restructure internal locking Date: Fri, 4 Nov 2022 15:57:32 +0100 Message-Id: <20221104145737.71236-12-anna-maria@linutronix.de> In-Reply-To: <20221104145737.71236-1-anna-maria@linutronix.de> References: <20221104145737.71236-1-anna-maria@linutronix.de> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 1b82661f6172..641e7284f0d7 100644 --- a/kernel/time/timer.c +++ b/kernel/time/timer.c @@ -1910,11 +1910,7 @@ static inline void __run_timers(struct timer_base *base) struct hlist_head heads[LVL_DEPTH]; int levels; - if (time_before(jiffies, base->next_expiry)) - return; - - timer_base_lock_expiry(base); - raw_spin_lock_irq(&base->lock); + lockdep_assert_held(&base->lock); while (time_after_eq(jiffies, base->clk) && time_after_eq(jiffies, base->next_expiry)) { @@ -1934,21 +1930,36 @@ 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); } +static void run_timer_base(int index) +{ + struct timer_base *base = 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 = 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); } } -- 2.30.2