Re: [PATCH bpf-next v6 1/7] bpf: Renames to prepare for generalizing sk_storage.

[KP Singh]

On 24.07.20 07:31, Martin KaFai Lau wrote:
> On Thu, Jul 23, 2020 at 01:50:26PM +0200, KP Singh wrote:
>> From: KP Singh <kpsingh@xxxxxxxxxx>
>>
>> A purely mechanical change to split the renaming from the actual
>> generalization.
>>
>> Flags/consts:
>>
>>   SK_STORAGE_CREATE_FLAG_MASK	BPF_LOCAL_STORAGE_CREATE_FLAG_MASK
>>   BPF_SK_STORAGE_CACHE_SIZE	BPF_LOCAL_STORAGE_CACHE_SIZE
>>   MAX_VALUE_SIZE		BPF_LOCAL_STORAGE_MAX_VALUE_SIZE
>>
>> Structs:
>>
>>   bucket			bpf_local_storage_map_bucket
>>   bpf_sk_storage_map		bpf_local_storage_map
>>   bpf_sk_storage_data		bpf_local_storage_data
>>   bpf_sk_storage_elem		bpf_local_storage_elem
>>   bpf_sk_storage		bpf_local_storage
>>   selem_linked_to_sk		selem_linked_to_storage
>>   selem_alloc			bpf_selem_alloc
>>
>> The "sk" member in bpf_local_storage is also updated to "owner"
>> in preparation for changing the type to void * in a subsequent patch.
>>
>> Functions:
>>
>>   __selem_unlink_sk			bpf_selem_unlink_storage
>>   __selem_link_sk			bpf_selem_link_storage
>>   selem_unlink_sk			__bpf_selem_unlink_storage
>>   sk_storage_update			bpf_local_storage_update
>>   __sk_storage_lookup			bpf_local_storage_lookup
>>   bpf_sk_storage_map_free		bpf_local_storage_map_free
>>   bpf_sk_storage_map_alloc		bpf_local_storage_map_alloc
>>   bpf_sk_storage_map_alloc_check	bpf_local_storage_map_alloc_check
>>   bpf_sk_storage_map_check_btf		bpf_local_storage_map_check_btf
> Thanks for separating this mechanical name change in a separate patch.
> It is much easier to follow.  This patch looks good.
> 
> A minor thought is, when I look at unlink_map() and unlink_storage(),
> it keeps me looking back for the lock situation.  I think
> the main reason is the bpf_selem_unlink_map() is locked but
> bpf_selem_unlink_storage() is unlocked now.  May be:
> 
> bpf_selem_unlink_map()		=> bpf_selem_unlink_map_locked()
> bpf_selem_link_map()		=> bpf_selem_link_map_locked()
> __bpf_selem_unlink_storage() 	=> bpf_selem_unlink_storage_locked()
> bpf_link_storage() means unlocked
> bpf_unlink_storage() means unlocked.
> 
> I think it could be one follow-up patch later instead of interrupting
> multiple patches in this set for this minor thing.  For now, lets
> continue with this and remember default is nolock for storage.
> 

Makes sense. I can update these in a separate patch if there are no
major changes needed in this one.

> I will continue tomorrow.

Awesome! Thanks :)

- KP

>