# Re: \[Intel-wired-lan\] \[PATCH net-next v5 0/7\] introduce DEFINE\_FLEX() macro

- From: Przemek Kitszel \<przemyslaw.kitszel@intel.com\>
- Date: 2023-09-19 11:11:23 
- List: netdev
- Page: https://ratatoskr.run/netdev/2023/09/11272358
- Thread: https://ratatoskr.run/netdev/2023/09/11271680/t.md

```text
On 9/12/23 18:16, Kees Cook wrote:
> On Tue, Sep 12, 2023 at 07:59:30AM -0400, Przemek Kitszel wrote:
>> Add DEFINE_FLEX() macro, that helps on-stack allocation of structures
>> with trailing flex array member.
>> Expose __struct_size() macro which reads size of data allocated
>> by DEFINE_FLEX().
>>
>> Accompany new macros introduction with actual usage,
>> in the ice driver - hence targeting for netdev tree.
>>
>> Obvious benefits include simpler resulting code, less heap usage,
>> less error checking. Less obvious is the fact that compiler has
>> more room to optimize, and as a whole, even with more stuff on the stack,
>> we end up with overall better (smaller) report from bloat-o-meter:
>> add/remove: 8/6 grow/shrink: 7/18 up/down: 2211/-2270 (-59)
>> (individual results in each patch).
>>
>> v5: same as v4, just not RFC
>> v4: _Static_assert() to ensure compiletime const count param
>> v3: tidy up 1st patch
>> v2: Kees: reusing __struct_size() instead of doubling it as a new macro
>>
>> Przemek Kitszel (7):
>>    overflow: add DEFINE_FLEX() for on-stack allocs
>>    ice: ice_sched_remove_elems: replace 1 elem array param by u32
>>    ice: drop two params of ice_aq_move_sched_elems()
>>    ice: make use of DEFINE_FLEX() in ice_ddp.c
>>    ice: make use of DEFINE_FLEX() for struct ice_aqc_add_tx_qgrp
>>    ice: make use of DEFINE_FLEX() for struct ice_aqc_dis_txq_item
>>    ice: make use of DEFINE_FLEX() in ice_switch.c
>
> Looks good to me! Feel free to pick up via netdev.
>
> -Kees
>

Thanks!

Patchwork [1] says it's "Awaiting Upstream", which is the same for most of the "to: IWL" patches. That means it's delegated to Tony?

By any means, minimizing "usage examples" to just ice driver makes it easy to merge via Tony's tree.

[1] https://patchwork.kernel.org/project/netdevbpf/patch/20230912115937.1645707-2-przemyslaw.kitszel@intel.com/
```