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

From: Dongli Zhang
Date: Thu Jan 03 2019 - 20:32:04 EST


Hi Konrad,

Would you please take a look on those two patches?

In addition, there is another patch correcting an error in comment.

https://lkml.org/lkml/2018/12/5/1721

Thank you very much!

Dongli Zhang

On 12/11/2018 05:05 AM, Joe Jin wrote:
> 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
>