From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-176.mta1.migadu.com (out-176.mta1.migadu.com [95.215.58.176]) (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 E61804D8BF for ; Thu, 30 May 2024 20:05:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.176 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717099522; cv=none; b=IWOny3Er31e5DVHOL/5VGHcUCiksv4NzUO6haJ/MYYdhNu019gtSr0Huh+vV02RdlXuKj/N7jVO9gT0n9ZFy+sgnfOoHKOsuCwWtSBRro2eJzggSvi7Tl2REVKO/XGgmxIYMflDK6p0v1+FTDLlLtNe//HS2Sixz3m9r7zSpO9Y= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717099522; c=relaxed/simple; bh=jfZjH7dPEZxsZkGq0Zc2HutaVqt4Wmi6QmjVBkp2ahw=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=I9uWJyyDe/LJcs+vi3AURUoH+MOntZfTvVzcQGcgNHyPu7QZpCQFxxK63+2BMTfFA8GS4I/gnDHlWwkVd4Lo3C/1o2N2cseofy8zN1C1DLWdDo/vtki0BzlZ+tgJ9siUkOVdsizo0GoyfwWrhuzMfC5irShbBzRaGUtvPGU+d7E= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=CFML5l7C; arc=none smtp.client-ip=95.215.58.176 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="CFML5l7C" X-Envelope-To: josef@toxicpanda.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1717099516; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=YpFa3Bx0Tf5ODURqiaCwQwbuuk80x2jm9JeNzuE+FHQ=; b=CFML5l7CVOz1FXmbeETe96hrRrhe/PJtIKJsSTChVh39w4jduf8c/47tK1+T73RK0dv2wx SEgPlBbaXiqxTEoMNxn1LGta3shETyBcQHP5W8ke/pxY+c6XWvNgJE1sAmJPzG87v3hOZN KxS7ZI1aS1ORKvOITQKMETs+oHdI5yc= X-Envelope-To: bernd.schubert@fastmail.fm X-Envelope-To: bschubert@ddn.com X-Envelope-To: miklos@szeredi.hu X-Envelope-To: amir73il@gmail.com X-Envelope-To: linux-fsdevel@vger.kernel.org X-Envelope-To: akpm@linux-foundation.org X-Envelope-To: linux-mm@kvack.org X-Envelope-To: mingo@redhat.com X-Envelope-To: peterz@infradead.org X-Envelope-To: avagin@google.com X-Envelope-To: io-uring@vger.kernel.org X-Envelope-To: axboe@kernel.dk X-Envelope-To: ming.lei@redhat.com X-Envelope-To: asml.silence@gmail.com Date: Thu, 30 May 2024 16:05:12 -0400 X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Kent Overstreet To: Josef Bacik Cc: Bernd Schubert , Bernd Schubert , Miklos Szeredi , Amir Goldstein , linux-fsdevel@vger.kernel.org, Andrew Morton , linux-mm@kvack.org, Ingo Molnar , Peter Zijlstra , Andrei Vagin , io-uring@vger.kernel.org, Jens Axboe , Ming Lei , Pavel Begunkov Subject: Re: [PATCH RFC v2 00/19] fuse: fuse-over-io-uring Message-ID: References: <20240529-fuse-uring-for-6-9-rfc2-out-v1-0-d149476b1d65@ddn.com> <5mimjjxul2sc2g7x6pttnit46pbw3astwj2giqfr4xayp63el2@fb5bgtiavwgv> <8c3548a9-3b15-49c4-9e38-68d81433144a@fastmail.fm> <20240530190941.GA2210558@perftesting> Precedence: bulk X-Mailing-List: io-uring@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: <20240530190941.GA2210558@perftesting> X-Migadu-Flow: FLOW_OUT On Thu, May 30, 2024 at 03:09:41PM -0400, Josef Bacik wrote: > On Thu, May 30, 2024 at 06:17:29PM +0200, Bernd Schubert wrote: > > > > > > On 5/30/24 18:10, Kent Overstreet wrote: > > > On Thu, May 30, 2024 at 06:02:21PM +0200, Bernd Schubert wrote: > > >> Hmm, initially I had thought about writing my own ring buffer, but then > > >> io-uring got IORING_OP_URING_CMD, which seems to have exactly what we > > >> need? From interface point of view, io-uring seems easy to use here, > > >> has everything we need and kind of the same thing is used for ublk - > > >> what speaks against io-uring? And what other suggestion do you have? > > >> > > >> I guess the same concern would also apply to ublk_drv. > > >> > > >> Well, decoupling from io-uring might help to get for zero-copy, as there > > >> doesn't seem to be an agreement with Mings approaches (sorry I'm only > > >> silently following for now). > > >> > > >> From our side, a customer has pointed out security concerns for io-uring. > > >> My thinking so far was to implemented the required io-uring pieces into > > >> an module and access it with ioctls... Which would also allow to > > >> backport it to RHEL8/RHEL9. > > > > > > Well, I've been starting to sketch out a ringbuffer() syscall, which > > > would work on any (supported) file descriptor and give you a ringbuffer > > > for reading or writing (or call it twice for both). > > > > > > That seems to be what fuse really wants, no? You're already using a file > > > descriptor and your own RPC format, you just want a faster > > > communications channel. > > > > Fine with me, if you have something better/simpler with less security > > concerns - why not. We just need a community agreement on that. > > > > Do you have something I could look at? > > FWIW I have no strong feelings between using iouring vs any other ringbuffer > mechanism we come up with in the future. > > That being said iouring is here now, is proven to work, and these are good > performance improvements. If in the future something else comes along that > gives us better performance then absolutely we should explore adding that > functionality. But this solves the problem today, and I need the problem solved > yesterday, so continuing with this patchset is very much a worthwhile > investment, one that I'm very happy you're tackling Bernd instead of me ;). > Thanks, I suspect a ringbuffer syscall will actually be simpler than switching to io_uring. Let me see if I can cook something up quickly - there's no rocket science here and this all stuff we've done before so it shouldn't take too long (famous last works...)