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From:   Christoph Hellwig <hch@lst.de>
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Subject: Re: [PATCH v4 0/8] Allow dynamic allocation of software IO TLB
 bounce buffers
Message-ID: <20230720082316.GB6932@lst.de>
References: <cover.1689261692.git.petr.tesarik.ext@huawei.com> <20230720065216.GB4395@lst.de> <20230720101320.72bbd2fc@meshulam.tesarici.cz>
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On Thu, Jul 20, 2023 at 10:13:20AM +0200, Petr Tesařík wrote:
> Fine with me. I removed it after all my testing showed no performance
> impact as long as the size of the initial SWIOTLB is kept at the
> default value (and sufficient for the workload), but it's OK for me if
> dynamic SWIOTLB allocations are off by default.
> 
> OTOH I'd like to make it a boot-time option rather than build-time
> option. Would that be OK for you?

I'd really like the config option to not even build the code.  But
a boot time option sounds very useful in addition to that.