On Wed, Mar 13, 2019 at 12:44 AM Michal Hocko <mhocko@xxxxxxxxxx> wrote: > > On Wed 13-03-19 00:29:57, Yafang Shao wrote: > > On Wed, Mar 13, 2019 at 12:18 AM Michal Hocko <mhocko@xxxxxxxxxx> wrote: > > > > > > On Sat 02-03-19 12:38:58, Yafang Shao wrote: > > > > Only mm_compaction_isolate_{free, migrate}pages may be used when > > > > CONFIG_COMPACTION is not set. > > > > All others are used only when CONFIG_COMPACTION is set. > > > > > > Why is this an improvement? > > > > > > > After this change, if CONFIG_COMPACTION is not set, the tracepoints > > that only work when CONFIG_COMPACTION is set will not be exposed to > > the usespace. > > Without this change, they will always be expose in debugfs no matter > > CONFIG_COMPACTION is set or not. > > And this is exactly something that the changelog should mention. I > wasn't aware that we do export tracepoints even when they are not used > by any code path. This whole macro based programming is just a black > magic. > -- Sure, I will modify the changelog and send v2. Thanks Yafang