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Date: Tue, 30 Jul 2024 11:16:37 +0300
From: Leon Romanovsky <leon@kernel.org>
To: Christoph Hellwig <hch@lst.de>
Cc: Mostafa Saleh <smostafa@google.com>,
	Robin Murphy <robin.murphy@arm.com>, Joerg Roedel <joro@8bytes.org>,
	Will Deacon <will@kernel.org>,
	Marek Szyprowski <m.szyprowski@samsung.com>,
	Easwar Hariharan <eahariha@linux.microsoft.com>,
	linux-kernel@vger.kernel.org, iommu@lists.linux.dev,
	Jason Gunthorpe <jgg@nvidia.com>
Subject: Re: [PATCH v2 2/2] dma: add IOMMU static calls with clear default ops
Message-ID: <20240730081637.GB4209@unreal>
References: <cover.1721219730.git.leon@kernel.org>
 <dd34bf3ecef252b4910d70aa21ff5273b5e8b19b.1721219730.git.leon@kernel.org>
 <ZqeN6MP4o2JNLcUz@google.com>
 <20240729171518.GB31388@lst.de>
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In-Reply-To: <20240729171518.GB31388@lst.de>

On Mon, Jul 29, 2024 at 07:15:18PM +0200, Christoph Hellwig wrote:
> On Mon, Jul 29, 2024 at 12:41:12PM +0000, Mostafa Saleh wrote:
> > Just out of curiosity, is there any observed improvement from that?
> > As from my experience the DMA-IOMMU path is quite dense so it won't
> > be senstive to such micro-optimizations.
> 
> We are trying to gradually fix this.   Part of that is adding not even
> more indirect calls for the next generation map API.  But another totally
> unrelated part is that we can compile out the dma ops entirely for
> common configs, which I really want because people are badly abusing it.

Christoph,

This is good remark, should I add this to the commit message and send v5?
v4: https://lore.kernel.org/all/cover.1721818168.git.leon@kernel.org/

Thanks