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Date:   Wed, 6 Jul 2022 13:31:08 +0200
From:   Joerg Roedel <joro@8bytes.org>
To:     Feng Tang <feng.tang@intel.com>
Cc:     Will Deacon <will@kernel.org>, Robin Murphy <robin.murphy@arm.com>,
        John Garry <john.garry@huawei.com>,
        iommu@lists.linux-foundation.org, iommu@lists.linux.dev,
        Andrew Morton <akpm@linux-foundation.org>,
        Christoph Lameter <cl@linux.com>,
        Vlastimil Babka <vbabka@suse.cz>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2] iommu/iova: change IOVA_MAG_SIZE to 127 to save memory
Message-ID: <YsVyfB8ygYm7owJo@8bytes.org>
References: <20220703114450.15184-1-feng.tang@intel.com>
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On Sun, Jul 03, 2022 at 07:44:50PM +0800, Feng Tang wrote:
> kmalloc will round up the request size to power of 2, and current
> iova_magazine's size is 1032 (1024+8) bytes, so each instance
> allocated will get 2048 bytes from kmalloc, causing around 1KB
> waste.
> 
> Change IOVA_MAG_SIZE from 128 to 127 to make size of 'iova_magazine'
> 1024 bytes so that no memory will be wasted.
> 
> Signed-off-by: Feng Tang <feng.tang@intel.com>
> Acked-by: Robin Murphy <robin.murphy@arm.com>

Applied, thanks.