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Message-ID: <0689cf4d-adaa-c783-98e8-ffbe73291ae1@bytedance.com>
Date:   Tue, 8 Nov 2022 11:43:56 +0800
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Subject: Re: [RESEND PATCH v3] iommu/iova: Optimize alloc_iova with
 rbtree_augmented
To:     Robin Murphy <robin.murphy@arm.com>, joro@8bytes.org,
        will@kernel.org
Cc:     wangjie125@huawei.com, iommu@lists.linux.dev,
        linux-kernel@vger.kernel.org, haifeng.zhao@linux.intel.com,
        john.garry@huawei.com
References: <20220922183114.15135-1-zhangpeng.00@bytedance.com>
 <4a1d000e-e051-5972-bacc-d785ceeed879@arm.com>
From:   Peng Zhang <zhangpeng.00@bytedance.com>
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> https://lore.kernel.org/linux-iommu/2b0ca6254dd0102bf559b2a73e9b51da089afbe3.1663764627.git.robin.murphy@arm.com/
I don't think this method solves the problem, because sometimes it's 
just that the allocation is very slow, it's not that it can't be allocated.

This is a test of the performance improvement of the network card by 
this patch:
https://lore.kernel.org/lkml/42909903-5b6c-efe8-9ed3-3ac012f1a421@huawei.com/
At least this optimization makes sense.

The only downside of this optimization is that it is more complex, if 
you think it is difficult to maintain it, I can help maintain it.

Thanks,
Peng.