From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 47DFFC433EF for ; Wed, 1 Jun 2022 18:12:45 +0000 (UTC) Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4LCy174vJDz3bpX for ; Thu, 2 Jun 2022 04:12:43 +1000 (AEST) Authentication-Results: lists.ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20201202 header.b=kBs/HAWx; dkim-atps=neutral Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=kernel.org (client-ip=145.40.73.55; helo=sin.source.kernel.org; envelope-from=nathan@kernel.org; receiver=) Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20201202 header.b=kBs/HAWx; dkim-atps=neutral Received: from sin.source.kernel.org (sin.source.kernel.org [145.40.73.55]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4LCy0N5g24z3blC for ; Thu, 2 Jun 2022 04:12:04 +1000 (AEST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by sin.source.kernel.org (Postfix) with ESMTPS id 9BED2CE1D21; Wed, 1 Jun 2022 18:12:01 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id BDA63C385A5; Wed, 1 Jun 2022 18:11:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1654107120; bh=XyRtnaG4f6v1X+0b1Icwpx1CnomvwrWKo4GYEBNHb+8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=kBs/HAWx4uM3HDoEzXU7+T8V9lyNwNqn4zd6Uh/AJGNo4QD8EzwUXHg8SF5aQu/eR anmAddXVYpYTPQXJYiVXSgAM6oeXwkinLakcGmSyuAZtpT4Gg5dXcDILW5BYrqp6yC vfOgfDXfoYgyw9l9+lVWSvldxx5jHryrGn/d5UzcJCJjQVQvAnn5PGnRbongr5jgLY JziHqqThI4bmA2WwIpuZHilJdJjc4uSPMPWYG0WUdO4ZhUny70sDURv0RtrDDn5Tm8 XZjMRYHCt4Yp4VSnSP3UbNmDy1oSOc8nqKRVMKzHpT2VEuCPCTYpdk41t0XRp7VTN5 o4MHC+cQamxCw== Date: Wed, 1 Jun 2022 11:11:57 -0700 From: Nathan Chancellor To: Christoph Hellwig Subject: Re: [PATCH 09/15] swiotlb: make the swiotlb_init interface more useful Message-ID: References: <20220404050559.132378-1-hch@lst.de> <20220404050559.132378-10-hch@lst.de> <20220601173441.GB27582@lst.de> <20220601175743.GA28082@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220601175743.GA28082@lst.de> X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-hyperv@vger.kernel.org, x86@kernel.org, linux-ia64@vger.kernel.org, linux-pci@vger.kernel.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, Stefano Stabellini , Joerg Roedel , Konrad Rzeszutek Wilk , tboot-devel@lists.sourceforge.net, xen-devel@lists.xenproject.org, David Woodhouse , Tom Lendacky , Anshuman Khandual , Boris Ostrovsky , linux-arm-kernel@lists.infradead.org, Juergen Gross , linuxppc-dev@lists.ozlabs.org, linux-mips@vger.kernel.org, iommu@lists.linux-foundation.org, Robin Murphy , Lu Baolu Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Wed, Jun 01, 2022 at 07:57:43PM +0200, Christoph Hellwig wrote: > On Wed, Jun 01, 2022 at 10:46:54AM -0700, Nathan Chancellor wrote: > > On Wed, Jun 01, 2022 at 07:34:41PM +0200, Christoph Hellwig wrote: > > > Can you send me the full dmesg and the content of > > > /sys/kernel/debug/swiotlb/io_tlb_nslabs for a good and a bad boot? > > > > Sure thing, they are attached! If there is anything else I can provide > > or test, I am more than happy to do so. > > Nothing interesting. But the performance numbers almost look like > swiotlb=force got ignored before (even if I can't explain why). I was able to get my performance back with this diff but I don't know if this is a hack or a proper fix in the context of the series. diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c index dfa1de89dc94..0bfb2fe3d8c5 100644 --- a/kernel/dma/swiotlb.c +++ b/kernel/dma/swiotlb.c @@ -276,7 +276,7 @@ void __init swiotlb_init_remap(bool addressing_limit, unsigned int flags, __func__, alloc_size, PAGE_SIZE); swiotlb_init_io_tlb_mem(mem, __pa(tlb), nslabs, false); - mem->force_bounce = flags & SWIOTLB_FORCE; + mem->force_bounce = swiotlb_force_bounce || (flags & SWIOTLB_FORCE); if (flags & SWIOTLB_VERBOSE) swiotlb_print_info(); > Do you get a similar performance with the new kernel without > swiotlb=force as the old one with that argument by any chance? I'll see if I can test that, as I am not sure I have control over those cmdline arguments. Cheers, Nathan