Re: [PATCH v2 1/2] swiotlb: add debugfs to track swiotlb buffer usage

From: Joe Jin
Date: Mon Dec 10 2018 - 16:06:07 EST


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