Re: [PATCH V2] dmabuf: ensure unique directory name for dmabuf stats

From: Charan Teja Kalla
Date: Tue May 10 2022 - 13:14:27 EST


On 5/10/2022 8:42 PM, Christian König wrote:
>>    * The information in the interface can also be used to derive
>> per-exporter
>>    * statistics. The data from the interface can be gathered on error
>> conditions
>> @@ -172,6 +172,7 @@ int dma_buf_stats_setup(struct dma_buf *dmabuf)
>>   {
>>       struct dma_buf_sysfs_entry *sysfs_entry;
>>       int ret;
>> +    static atomic64_t unique_id = ATOMIC_INIT(0);
>
> Please move that to the beginning of the declarations.
>

Done. Any scripts I can run at my end to catch these type of trivial
changes? checkpatch.pl didn't report this coding style.

>>         if (!dmabuf || !dmabuf->file)
>>           return -EINVAL;
>> @@ -192,7 +193,8 @@ int dma_buf_stats_setup(struct dma_buf *dmabuf)
>>         /* create the directory for buffer stats */
>>       ret = kobject_init_and_add(&sysfs_entry->kobj, &dma_buf_ktype,
>> NULL,
>> -                   "%lu", file_inode(dmabuf->file)->i_ino);
>> +                   "%lu-%lu", file_inode(dmabuf->file)->i_ino,
>
> Why not just use the unique value here? Or is the inode number necessary
> for something?

This will ease the debugging a lot. Given the dump, I can easily map
which dmabuf buffer to the process. On the crashutilty I just have to
search for this inode in the files output, just one example.