From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from relay.hostedemail.com (smtprelay0015.hostedemail.com [216.40.44.15]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3BDDA1A6828 for ; Thu, 20 Aug 2026 17:00:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=216.40.44.15 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787245245; cv=none; b=lJrvFqwG88YdPKHnv0miMmz36G+/OVIYQ/akqa83n1FvMEhNGkNo4PUIcqVezp6hI8qQ6Vun0+8pLeFWMWJthyRE0+8XHwYDZKJloRmckQ5EtL+ggnAK7vsJOCl4JQDoaUTTTtssgM2JYzJxCDnRaIUBtMO4G2IxoTl68MDfxLo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787245245; c=relaxed/simple; bh=d73/65O3EJddd94Ftz8cuWaU8eHaHvSROcHFwtE9Hgc=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=nGUwYAVNIxInjfQyKc4dy7Ox/TCD/arN2WBXUIn4XBeQTku+iZVDPS390wm8l5DBvm/53qqBpAUPkXIA0f87294NnLcZkC9HsUeoqIM/qfG5zB8m4hRzNC9PzLwNwDMPzHS0UOz/UBgvRceM0x6erfxUArmNj3m5caUlvWJCDMg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=goodmis.org; spf=pass smtp.mailfrom=goodmis.org; dkim=pass (1024-bit key) header.d=goodmis.org header.i=@goodmis.org header.b=jj2oXFg+; arc=none smtp.client-ip=216.40.44.15 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=goodmis.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=goodmis.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=goodmis.org header.i=@goodmis.org header.b="jj2oXFg+" Received: from omf08.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay09.hostedemail.com (Postfix) with ESMTP id EB18180205; Thu, 20 Aug 2026 17:00:34 +0000 (UTC) Received: from [HIDDEN] (Authenticated sender: rostedt@goodmis.org) by omf08.hostedemail.com (Postfix) with ESMTPA id 6426620025; Thu, 20 Aug 2026 17:00:31 +0000 (UTC) Date: Thu, 20 Aug 2026 13:00:28 -0400 From: Steven Rostedt To: Sebastian Andrzej Siewior Cc: Frederic Weisbecker , rcu@vger.kernel.org, linux-rt-devel@lists.linux.dev, Lai Jiangshan , "Paul E. McKenney" , Josh Triplett , Mathieu Desnoyers , Clark Williams Subject: Re: [PATCH] rcu: Use IRQ_WORK_INIT_HARD for srcu's irq_work Message-ID: <20260820130028.2243d53c@fedora> In-Reply-To: <20260820135500.hXUAsbHR@linutronix.de> References: <20260820110008.v2Tlr0_H@linutronix.de> <20260820135500.hXUAsbHR@linutronix.de> X-Mailer: Claws Mail 4.4.0 (GTK 3.24.52; x86_64-redhat-linux-gnu) Precedence: bulk X-Mailing-List: linux-rt-devel@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Stat-Signature: x3tiiugppggnx6wiqjuqr5h8oao16osf X-Rspamd-Server: rspamout04 X-Rspamd-Queue-Id: 6426620025 X-Session-Marker: 726F737465647440676F6F646D69732E6F7267 X-Session-ID: U2FsdGVkX1+cYqxSlDBmypQWZzLVcosmGzgtLlKeV9Y= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=goodmis.org; h=date:from:to:cc:subject:message-id:in-reply-to:references:mime-version:content-type:content-transfer-encoding; s=dkim1; bh=FbDr8IlhceKKRQEH2RbCZ5jCU04Uji7h/bs380CjYLg=; b=jj2oXFg+NBbbqf4HDPMcFit4Knn+DRcam6pz3XuZzzshOQwItmRRGhvuzWZKn/axgE92elBEhf+OSzQdjnTT07PZSM2KpZYXySbIdULocWru5MRkobtj05sMIxlYFur3G+6m8dHE6UxdNDXzepmjehxsClMVv1us6um/5nutvcA= X-HE-Tag: 1787245231-857373 X-HE-Meta: U2FsdGVkX19DDQutVmD+VA+U3XpEOOiyVS/hUGjYTgfoSQIG7LOvSq86GPbOq9YlI3qOfyUXKamsIaCj3TMEgBKW8QU2gjh6L+6BYbRWI2x99eUtR1wtJAa2C9e3VaugFz3KmiqiiUk3jQwcS0GF6xxpJ+OWe4jCeuCluXSB85Iqoe+4/+twiqOBjCNpHEyLwk4pyWOoicp8NoxtFEccsa6aa5pR47BDuK4OZwhCWP/yMIMVvjeLeB+eu4m6Rhupn1T1zLK5jyXCa4UwlhSvVnwJyEnba901zOsg3eku+bxW3X/T6tFFoDvSi1J2lMJ9U/GYWGh2tvh14FzAgRHguRQQ2tVo8A968J3J2fLmRoGINmK11V3OCshNpgHeS7Rc On Thu, 20 Aug 2026 15:55:00 +0200 Sebastian Andrzej Siewior wrote: > > > diff --git a/kernel/rcu/srcutree.c b/kernel/rcu/srcutree.c > > > index 7c2f7cc131f7a..b703233d4a63f 100644 > > > --- a/kernel/rcu/srcutree.c > > > +++ b/kernel/rcu/srcutree.c > > > @@ -218,7 +218,7 @@ static int init_srcu_struct_fields(struct srcu_struct *ssp, bool is_static) > > > mutex_init(&ssp->srcu_sup->srcu_barrier_mutex); > > > atomic_set(&ssp->srcu_sup->srcu_barrier_cpu_cnt, 0); > > > INIT_DELAYED_WORK(&ssp->srcu_sup->work, process_srcu); > > > - init_irq_work(&ssp->srcu_sup->irq_work, srcu_irq_work); > > > + ssp->srcu_sup->irq_work = IRQ_WORK_INIT_HARD(srcu_irq_work); > > > > It may need a comment to not lose that. I agree a comment would be useful here. > > We could also make irq_work.o earlier in the Makefile, right at the top > so it comes before tracing. This was one of the first ideas and makes > the issue also go away. But given that it is just a wake we avoid waking > the irq_work/ thread just to schedule a timer/ wake workqueue. That doesn't sound as robust as this solution. Updating Makefile order is a fragile solution. Anyway for this patch, Reviewed-by: Steven Rostedt