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Subject: Re: [PATCH v2 1/2] swiotlb: add debugfs to track swiotlb buffer usage
To:     Tim Chen <tim.c.chen@linux.intel.com>,
        Dongli Zhang <dongli.zhang@oracle.com>,
        iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org
Cc:     konrad.wilk@oracle.com, hch@lst.de, m.szyprowski@samsung.com,
        robin.murphy@arm.com
References: <1544402278-8175-1-git-send-email-dongli.zhang@oracle.com>
 <41becd27-8c3a-da2b-e5ed-e361ba20e4d4@linux.intel.com>
From:   Joe Jin <joe.jin@oracle.com>
Message-ID: <34883ba5-b444-3d37-4d40-9b0a651dd2eb@oracle.com>
Date:   Mon, 10 Dec 2018 13:05:44 -0800
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On 12/10/18 12:00 PM, Tim Chen wrote:
>> @@ -528,6 +538,9 @@ phys_addr_t swiotlb_tbl_map_single(struct device *hwdev,
>>  		dev_warn(hwdev, "swiotlb buffer is full (sz: %zd bytes)\n", size);
>>  	return SWIOTLB_MAP_ERROR;
>>  found:
>> +#ifdef CONFIG_DEBUG_FS
>> +	io_tlb_used += nslots;
>> +#endif
> One nit I have about this patch is there are too many CONFIG_DEBUG_FS.
> 
> For example here, instead of io_tlb_used, we can have a macro defined,
> perhaps something like inc_iotlb_used(nslots).  It can be placed in the
> same section that swiotlb_create_debugfs is defined so there's a single
> place where all the CONFIG_DEBUG_FS stuff is located.
> 
> Then define inc_iotlb_used to be null when we don't have
> CONFIG_DEBUG_FS.
> 

Dongli had removed above ifdef/endif on his next patch, "[PATCH v2 2/2]
swiotlb: checking whether swiotlb buffer is full with io_tlb_used"

Thanks,
Joe