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> > + int old = 0; > > + > > + if (!atomic_try_cmpxchg(&only_once, &old, 1)) > > + return; > > +} > > There's > > #define DO_ONCE(func, ...) > > Can't use that? Learn something new every day. Yes, looks possible here. Though I believe I'll need the DO_ONCE_SLEEPABLE() version since resctrl_arch_pre_mount() grabs a mutex and various called functions allocate memory using kmalloc(). -Tony