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 A382C1D4328; Tue, 19 Nov 2024 16:45:29 +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=1732034729; cv=none; b=jgPerMrPqzESNSsWPP4GYCky722UDvuSO6ikFI2EHU8sC7tpzXBEUDotdeuPvNVOqtRYRTzJFfUmRahgZUxOnWkFMUCL1QsDL+EqhH6pY8dDAhvBUdD/CNXWlNJs6uCsaE97IX2u3S2+1e9meMuRAf09sJpYKbOI7PG12JdN/ko= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1732034729; c=relaxed/simple; bh=Q/BSK4ar/SbHR2TxWlzS2iHmY3WRpuywNmlNZgy7vbc=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=IcqRZOK+P/TpqxctruE+3Fw0/FXm+T7NJuwbctP1RfbVIsz8hdktUKN9+dbGLjB6v2TWiVMgF3IbjvuGOD7lirUjJxs+fzWGo8TsjCPtOKtexirGSo/XqrvnXdDC15TnnxGyS00f4ByBkLbFr/4hFMDY5j309FfKSoGZKVP1n6I= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 Received: by smtp.kernel.org (Postfix) with ESMTPSA id DA3A1C4CECF; Tue, 19 Nov 2024 16:45:22 +0000 (UTC) Date: Tue, 19 Nov 2024 11:45:56 -0500 From: Steven Rostedt To: Valentin Schneider Cc: linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, kvm@vger.kernel.org, linux-mm@kvack.org, bpf@vger.kernel.org, x86@kernel.org, rcu@vger.kernel.org, linux-kselftest@vger.kernel.org, Masami Hiramatsu , Jonathan Corbet , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , "H. Peter Anvin" , Paolo Bonzini , Wanpeng Li , Vitaly Kuznetsov , Andy Lutomirski , Peter Zijlstra , Frederic Weisbecker , "Paul E. McKenney" , Neeraj Upadhyay , Joel Fernandes , Josh Triplett , Boqun Feng , Mathieu Desnoyers , Lai Jiangshan , Zqiang , Andrew Morton , Uladzislau Rezki , Christoph Hellwig , Lorenzo Stoakes , Josh Poimboeuf , Jason Baron , Kees Cook , Sami Tolvanen , Ard Biesheuvel , Nicholas Piggin , Juerg Haefliger , Nicolas Saenz Julienne , "Kirill A. Shutemov" , Nadav Amit , Dan Carpenter , Chuang Wang , Yang Jihong , Petr Mladek , "Jason A. Donenfeld" , Song Liu , Julian Pidancet , Tom Lendacky , Dionna Glaze , Thomas =?UTF-8?B?V2Vpw59zY2h1aA==?= , Juri Lelli , Marcelo Tosatti , Yair Podemsky , Daniel Wagner , Petr Tesarik Subject: Re: [RFC PATCH v3 00/15] context_tracking,x86: Defer some IPIs until a user->kernel transition Message-ID: <20241119114556.0949b562@gandalf.local.home> In-Reply-To: <20241119153502.41361-1-vschneid@redhat.com> References: <20241119153502.41361-1-vschneid@redhat.com> X-Mailer: Claws Mail 3.20.0git84 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Tue, 19 Nov 2024 16:34:47 +0100 Valentin Schneider wrote: > Context > ======= > > We've observed within Red Hat that isolated, NOHZ_FULL CPUs running a > pure-userspace application get regularly interrupted by IPIs sent from > housekeeping CPUs. Those IPIs are caused by activity on the housekeeping CPUs > leading to various on_each_cpu() calls, e.g.: FYI, Sending a patch series at the start of the merge window is likely going to get ignored. Care to resend after rc1 is released? Or at least ping about it. -- Steve