From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 46469285068 for ; Sat, 6 Dec 2025 08:52:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765011139; cv=none; b=uMvdkA2bfuHfT0x19g9dr60JN/+gYsb0GH96M51uJsUvdwe5c0xGu0K6seEH9zS2oU1jGc2/2qsoM3ssCNu70APmxddy2KJZ7s6/6m7SAXJl0jHcpqA1YgT0qmkjtP8TZMw7P8VydJrJ6xl9ktsODAPgq9Yu2wHvUNRoSVP98tg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765011139; c=relaxed/simple; bh=WWsjCNZRbVpyrlu6lG+jThr5OTa7izlOwina8QoTdB8=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=aUnTXyEAaUFHyqiFkCiQoPFs2jBC3Q8k6sB50iGAfc/0/vFB/wrv1RyeP/Qz8VcZImTBb3Bwa9jjXGJMrgK/SurJRQwuDvBEmlZNYjG1GklCjhDgWgEZObCWjmcY6Fefth/Lt8C/EUwfmRn+9IwksrLpRxYmNkros+kMvzy0dw0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=bowpjBTU; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="bowpjBTU" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9C794C4CEF5; Sat, 6 Dec 2025 08:52:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1765011138; bh=WWsjCNZRbVpyrlu6lG+jThr5OTa7izlOwina8QoTdB8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=bowpjBTULMMp7wRDfALg2jSeFaR7DGis55qAyJZyhJZmt9MdYHyBqNWp6BHmp0saX smxUXaier5k3r29SRvri2uiimI13VxJedBDK1SOigRJ2Y2kEI+4zW3fpXTVmOvY3oQ Lv1uFab4faFma878M7sj5seOzuJCokJSNHzvoHEVma+anW4n0C6QL7vPcb+dN5xGBh UPpMtWeC14DsoNOOfnz9nlfgmBZmpHtwB54WoYfGGHnbM4yWQGk7fKwBNdSaQK0xcy Z2D9Nm/z1GQ8gLnvtMqqth98VIkKy9w6xGfAntSi/Bs7WttFqCYacGpKRiA0cVZgvu s1hvQxSau84OQ== Date: Sat, 6 Dec 2025 09:52:14 +0100 From: Ingo Molnar To: Peter Zijlstra Cc: arnd@arndb.de, oleg@redhat.com, linux-kernel@vger.kernel.org Subject: Re: seqlock: Cure some more scoped_seqlock() optimization fails Message-ID: References: <20251204104332.GG2528459@noisy.programming.kicks-ass.net> 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: <20251204104332.GG2528459@noisy.programming.kicks-ass.net> * Peter Zijlstra wrote: > Arnd reported an x86 randconfig using gcc-15 tripped over > __scoped_seqlock_bug(). Turns out GCC chose not to inline the > scoped_seqlock helper functions and as such was not able to optimize > properly. BTW., I found a Clang randconfig too that fails the build, so it's not limited to GCC. Thanks, Ingo