From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Zijlstra Subject: [PATCH v2 14/44] cpuidle,cpu_pm: Remove RCU fiddling from cpu_pm_{enter,exit}() Date: Mon, 19 Sep 2022 11:59:53 +0200 Message-ID: <20220919101521.274051658@infradead.org> References: <20220919095939.761690562@infradead.org> Mime-Version: 1.0 Return-path: DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=Content-Type:MIME-Version:References: Subject:Cc:To:From:Date:Message-ID:Sender:Reply-To:Content-Transfer-Encoding: Content-ID:Content-Description:In-Reply-To; bh=vB057xACRVSJThllhGE8f2SmJ9TT+oL90mm46lxduII=; b=kywikNV+JOhuRC6ERD1VlqqQP3 erY7uC0VJQwPrnJCDMV8vfbpvSyHcY5xZAwrHnLhU5SZPz5xsRyEakEPdOOJm3k5Xas/FH1DSzD0x JpjT7nP0xdYKwFrD4JURDMdgc59IXKV8ZuNXomLhDpG/Fj4XRo/JBHLnr5d8v3/5Fr6jiBv6mjn0F 0/mLjpSN/K9XY5Ib4bNuBDGghVOMVV0dUFwAUO+xXbcCitVgxm2fBTuHCaU8/6F92gZK0Sn/AvWyA UiOBLuXdDZrgv/G0qDliEH3JMAvX3TIRnlGHv57WGn7U9pGViPVLLg38RK01Fa5hPm/uyqkvYdoqF pVe3AaZA==; List-ID: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: peterz@infradead.org Cc: richard.henderson@linaro.org, ink@jurassic.park.msu.ru, mattst88@gmail.com, vgupta@kernel.org, linux@armlinux.org.uk, ulli.kroll@googlemail.com, linus.walleij@linaro.org, shawnguo@kernel.org, Sascha Hauer , kernel@pengutronix.de, festevam@gmail.com, linux-imx@nxp.com, tony@atomide.com, khilman@kernel.org, catalin.marinas@arm.com, will@kernel.org, guoren@kernel.org, bcain@quicinc.com, chenhuacai@kernel.org, kernel@xen0n.name, geert@linux-m68k.org, sammy@sammy.net, monstr@monstr.eu, tsbogend@alpha.franken.de, dinguyen@kernel.org, jonas@southpole.se, stefan.kristiansson@saunalahti.fi, shorne@gmail.com, James.Bottomley@HansenPartnership.com, deller@gmx.de, mpe@ellerman.id.au, npiggin@gmail.com, christophe.leroy@csgroup.eu, paul.walmsley@sifive.com, palmer@dabbel All callers should still have RCU enabled. Signed-off-by: Peter Zijlstra (Intel) Acked-by: Mark Rutland --- kernel/cpu_pm.c | 9 --------- 1 file changed, 9 deletions(-) --- a/kernel/cpu_pm.c +++ b/kernel/cpu_pm.c @@ -30,16 +30,9 @@ static int cpu_pm_notify(enum cpu_pm_eve { int ret; - /* - * This introduces a RCU read critical section, which could be - * disfunctional in cpu idle. Copy RCU_NONIDLE code to let RCU know - * this. - */ - ct_irq_enter_irqson(); rcu_read_lock(); ret = raw_notifier_call_chain(&cpu_pm_notifier.chain, event, NULL); rcu_read_unlock(); - ct_irq_exit_irqson(); return notifier_to_errno(ret); } @@ -49,11 +42,9 @@ static int cpu_pm_notify_robust(enum cpu unsigned long flags; int ret; - ct_irq_enter_irqson(); raw_spin_lock_irqsave(&cpu_pm_notifier.lock, flags); ret = raw_notifier_call_chain_robust(&cpu_pm_notifier.chain, event_up, event_down, NULL); raw_spin_unlock_irqrestore(&cpu_pm_notifier.lock, flags); - ct_irq_exit_irqson(); return notifier_to_errno(ret); }