From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 1952736C5A1; Tue, 16 Jun 2026 14:19:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781619571; cv=none; b=t+3q1xdIsvd/rEDAfRzH5A0OmpNnHC2gRWAfl5C2o4MiJzRRJ9GrFwsJ5UoBBLQbeicjfBE3nZuwYzoPUZrtjrR4ysRjP0U6PlFF/6ruz0h8w0BlbkFjTnMjOvCqfDhC0hv6oceUi5dpsc4BX+6Ex6pOyodcplIYFb/QXcNNAMI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781619571; c=relaxed/simple; bh=xx3JY+nw+vD+MeNzO9y6Tvhc8OxsXr/lDPDffxRwMks=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=B7uIxfe7imc0Y1XtCG+x5j0K6fQ2lND3fMcBxxYRkYUikQGhqL5tw4hCvWY3RxTbaDOyNQGIGcSn+G/UyCt9A3J3IbCSLE0nSNdz8At/nXY7DByeVcZvgDCvSroqTDMGda5w5admC++CWZeB1HsHUuOqm2YZcSUI9z6ADxDpTCk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=nbtQtx7N; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="nbtQtx7N" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8CF3A1F000E9; Tue, 16 Jun 2026 14:19:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1781619570; bh=TuMB1Cm/aGP2t+Gael1c7mrQyJ5/TJDwQC8EFAv72aU=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=nbtQtx7Nm1tIkliz6+m4mKO8cfw5U7EQ6Zym158GRGp/TWQuS/W3Z3vdYAJMZw2q2 YVWF45pEzuYPkcLayGehL9EpLQLg7C+W5jnOYhfuU/dF7yBcpM04Q/SzkCzGIuKjdt G0BnRI2lZsvKljecN3nRgKJvdK/z9HgCXxqfhJcmq1sictNzAD4K5OEf+iaidtLDm8 +EUfg0/FPBjBqShUdVDA7NbHEntle/E4MQlp9AkrdgL8HWrtaTIPvPQIb9OY4gWmLB ddMCtuTwQqwKerrQNbTAk1WIOd+OQyYqUsk4+ZYfK6fwyiqGSSBBY3235yKkV9/4sI v6xpwa3Iu5ZlQ== Message-ID: <75fcf6f3-90a1-4002-be43-38b627a28833@kernel.org> Date: Tue, 16 Jun 2026 16:19:25 +0200 Precedence: bulk X-Mailing-List: virtualization@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [RFC PATCH 1/2] virtio-balloon: extend stats with memory composition and pressure data To: Gregory Price Cc: virtualization@lists.linux.dev, linux-kernel@vger.kernel.org, kernel-team@meta.com, mst@redhat.com, jasowang@redhat.com, xuanzhuo@linux.alibaba.com, eperezma@redhat.com, hannes@cmpxchg.org, surenb@google.com, peterz@infradead.org, mingo@redhat.com, juri.lelli@redhat.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de, vschneid@redhat.com, kprateek.nayak@amd.com References: <20260513165006.2790857-1-gourry@gourry.net> <20260513165006.2790857-2-gourry@gourry.net> <8e766803-e68d-4efd-a69e-cec5b2492988@kernel.org> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 6/16/26 15:49, Gregory Price wrote: > On Tue, Jun 16, 2026 at 02:30:34PM +0200, David Hildenbrand (Arm) wrote: >> >> Nothing too crazy here, however, the question is which of these values we >> actually want to guarantee that we will provide them with unchanged semantics in >> the future ... I guess anything we already expose to user space is alright >> (because it effectively already must remain mostly unchanged I assume). >> > > I suppose a risk of them going away entirely? I suppose that's > fixable but unlikely. Yeah, the first bunch is all exported through /proc/vmstat AFAIKS. The other through /proc/pressure/ So I assume this is just fine. -- Cheers, David