From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 0B42F1D89FD; Wed, 11 Jun 2025 06:57:33 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.137.202.133 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749625055; cv=none; b=pL8+fGa0W9WsIQvDf9AWOgaA8aKiXlBrglx5xK6PXRrj5cFIHn6/8TtykQ9AlKYNalunX3NMTGt2EqQQLtPp/jSDj1ghiAxlvbhkUAPg1p/lJzwGN79eU5GaNgGyVbUrN/4KYEM/IIcE+B/DmmJRj/E0sYd54gQ0zzTo+Wb8DTc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749625055; c=relaxed/simple; bh=iTvPrdxsLTgq9OW4OYumyHmWPPRUmKZHcH1+dMoShWo=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=XuheRhH+RFA57Y1Vp1yVm65WLdH1wa6Bq2YNZ9/pVuYWVCz6xBSh7UuJm9cemMAFsob9cajN/Q1HNlqcE2PaXO1yOHFu77BkcJSdiygiNNAGTigflRmj8YTe7nQfB89BilwPhlfznx3il01x/q6Ye8FmWlLkBXPENBhRsvgwzZE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=bombadil.srs.infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=xUZVpeuq; arc=none smtp.client-ip=198.137.202.133 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=bombadil.srs.infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="xUZVpeuq" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; 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=sMFeeB2Dbw5/O7ZYak8/g+wqndrxD4CXLJoYtiEdRTM=; b=xUZVpeuq12ugfHxzsCL8l9NrYN yosVwPldiPGTgKZaxocUBhVZy3lK6m5XKRl5ZU+Smn11j25kR8Ld1a4wdOhEVIUD2M2LkfbZDERf8 uaRzzUrHBVy9jXWdqaewtK7sK4NdhxFqbrj7MFrfXXyPGbtgEQMpWYpA2UEjf7KjYu3pBw+L24BtI 3Y5VM95PaHKJ3CW5tUhOLolSXcvzN98uqxnoLi5PBJdhNleDpNmeqSBKYoGgpW/ewXzvNX2bIHEVN 1La/UiDMHCI8n75PhECR9nr1NDxnq8cLxmr8IdDfCnuuoW+ZHK9j62Kwmg6sjruURS1DkXLxE+XUq M07fDDvA==; Received: from hch by bombadil.infradead.org with local (Exim 4.98.2 #2 (Red Hat Linux)) id 1uPFOv-000000093Ez-2nbu; Wed, 11 Jun 2025 06:57:33 +0000 Date: Tue, 10 Jun 2025 23:57:33 -0700 From: Christoph Hellwig To: Mike Snitzer Cc: Chuck Lever , Jeff Layton , linux-nfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, Jens Axboe Subject: Re: [PATCH 1/6] NFSD: add the ability to enable use of RWF_DONTCACHE for all IO Message-ID: References: <20250610205737.63343-1-snitzer@kernel.org> <20250610205737.63343-2-snitzer@kernel.org> Precedence: bulk X-Mailing-List: linux-nfs@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: <20250610205737.63343-2-snitzer@kernel.org> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html On Tue, Jun 10, 2025 at 04:57:32PM -0400, Mike Snitzer wrote: > Add 'enable-dontcache' to NFSD's debugfs interface so that: Any data > read or written by NFSD will either not be cached (thanks to O_DIRECT) > or will be removed from the page cache upon completion (DONTCACHE). > > enable-dontcache is 0 by default. It may be enabled with: > echo 1 > /sys/kernel/debug/nfsd/enable-dontcache Having this as a global debug-only interface feels a bit odd.