Hi Michal, On 3/4/20 4:53 PM, Michal Hocko wrote: > On Wed 04-03-20 14:23:48, Vincenzo Frascino wrote: >> mem_cgroup_id_get_many() is currently used only when MMU or MEMCG_SWAP >> configuration options are enabled. Having them disabled triggers the >> following warning at compile time: >> >> linux/mm/memcontrol.c:4797:13: warning: ‘mem_cgroup_id_get_many’ defined >> but not used [-Wunused-function] >> static void mem_cgroup_id_get_many(struct mem_cgroup *memcg, unsigned >> int n) >> >> Make mem_cgroup_id_get_many() dependent on MMU and MEMCG_SWAP to address >> the issue. > > A similar patch has been proposed recently > http://lkml.kernel.org/r/87fthjh2ib.wl-kuninori.morimoto.gx@xxxxxxxxxxx. > The conclusion was that the warning is not really worth adding code. > Thank you for pointing this out, I was not aware of it. I understand that you are against "#ifdeffery" in this case, but isn't it the case of adding at least __maybe_unused? This would prevent people from reporting it over and over again and you to have to push them back :) Let me know what do you think, in case I am happy to change my patch accordingly. [...] -- Regards, Vincenzo