From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (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 BF6DF21576E for ; Sat, 7 Mar 2026 13:16:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=90.155.92.199 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772889416; cv=none; b=FqQ5y+jw5TJzTMPQvnm36qF7In4e1fRje6L98KfQCRGUk2u7N7EuUv27w5+9hXjFDEMSbATe8/q9VGnh1iqDiwkEzv2kRYPRADg6dqi5bkQlSeZfY03bIn/JI73iAZS+hFPIkYmu1RMCJEcUtcc1KqDIRcIRsvncnFt+QMmOSLI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772889416; c=relaxed/simple; bh=K5k/Bgn1kIbv+73qndGQ6L5w3idx5weuTT+TuZuRbqM=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=m0iMVAa75t+Uug9e7VaKKYPtEhsikLgaZZunHCuXzaaizHxYfGYbmGfvOpQcE+W/+GUGVHvO5RTQctOBLLgR6AqJg6/xVmos91VdwIJvkYKRIvT75fcpoZoHwdwXGD3sGnaQx+Ii2ZXrqIedVxlvFZ1DcAYw6Lh3+qzN0lHdn58= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=Q2i0nwCD; arc=none smtp.client-ip=90.155.92.199 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="Q2i0nwCD" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=ShhLXfmi4XDHi0Xan3xm2hmkxBaUBNG7KGAvGxR0t6M=; b=Q2i0nwCDDsuPaCWYvH3CSOQLCw WWTpe5e4Y20X6V9wZmehitffjqAJXRfDYoRirg9KWfBlk+M+0g5PDj+1AZ3imMSOBUrdy/MyjS0mz 8cd6ONL6Of45gS/xq9qDaMNIJ3jO/UX8fW8Hrakcn++NDz4IOyuH/H2HaRGngZblNgBLUcIZsq50r bt+i6ZP/Tq8AqV1wAUbMTH9DkG3KauqM2xrc1Gz8ScdEzTSxMDCGbekvmarqQrvSMF14d1ddTImbv /PCnkZlfLR5tX8wOO7DoOPJDBmZnu8/wDHybbdvofLDzVcjwrAPtshLlnBVoG/HKXFpA/rZODjhG+ Xep1iWCA==; Received: from 77-249-17-252.cable.dynamic.v4.ziggo.nl ([77.249.17.252] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.98.2 #2 (Red Hat Linux)) id 1vyrWM-0000000AGNh-11jr; Sat, 07 Mar 2026 13:16:42 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 1000) id 0DCDE301150; Sat, 07 Mar 2026 14:16:41 +0100 (CET) Date: Sat, 7 Mar 2026 14:16:41 +0100 From: Peter Zijlstra To: Vlastimil Babka Cc: Steven Rostedt , Andrew Morton , Dmitry Ilvokhin , David Hildenbrand , Lorenzo Stoakes , "Liam R. Howlett" , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Brendan Jackman , Johannes Weiner , Zi Yan , linux-mm@kvack.org, linux-kernel@vger.kernel.org, kernel-team@meta.com Subject: Re: [PATCH 1/8] mm: use zone lock guard in reserve_highatomic_pageblock() Message-ID: <20260307131641.GX606826@noisy.programming.kicks-ass.net> References: <20260306095336.a79fcc869a7f6d2b2e97501b@linux-foundation.org> <20260306130052.7da8eab3@gandalf.local.home> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Fri, Mar 06, 2026 at 07:24:56PM +0100, Vlastimil Babka wrote: > Yeah I don't think the guard construct in this case should be doing anything > here that wouldn't allow the compiler to compile to the exactly same result > as before? Either there's some problem with the infra, or we're just victim > of compiler heuristics. In both cases imho worth looking into rather than > rejecting the construct. I'd love to look into it, but I can't seem to apply these patches to anything. By virtue of not actually having the patches, I had to resort to b4, and I think the incantation is something like: b4 shazam cover.1772811429.git.d@ilvokhin.com but it doesn't want to apply to anything I have at hand. Specifically, I tried Linus' tree and tip, which is most of what I have at hand.