On Tue, 26 Jun 2012, Glauber Costa wrote: > > > diff --git a/include/linux/thread_info.h b/include/linux/thread_info.h > > > index ccc1899..914ec07 100644 > > > --- a/include/linux/thread_info.h > > > +++ b/include/linux/thread_info.h > > > @@ -61,6 +61,12 @@ extern long do_no_restart_syscall(struct restart_block > > > *parm); > > > # define THREADINFO_GFP (GFP_KERNEL | __GFP_NOTRACK) > > > #endif > > > > > > +#ifdef CONFIG_CGROUP_MEM_RES_CTLR_KMEM > > > +# define THREADINFO_GFP_ACCOUNTED (THREADINFO_GFP | __GFP_KMEMCG) > > > +#else > > > +# define THREADINFO_GFP_ACCOUNTED (THREADINFO_GFP) > > > +#endif > > > + > > > > This type of requirement is going to become nasty very quickly if nobody > > can use __GFP_KMEMCG without testing for CONFIG_CGROUP_MEM_RES_CTLR_KMEM. > > Perhaps define __GFP_KMEMCG to be 0x0 if it's not enabled, similar to how > > kmemcheck does? > > > That is what I've done in my first version of this patch. At that time, > Christoph wanted it to be this way so we would make sure it would never be > used with #CONFIG_CGROUP_MEM_RES_CTLR_KMEM defined. A value of zero will > generate no errors. Undefined value will. > > Now, if you ask me, I personally prefer following what kmemcheck does here... > Right, because I'm sure that __GFP_KMEMCG will be used in additional places outside of this patchset and it will be a shame if we have to always add #ifdef's. I see no reason why we would care if __GFP_KMEMCG was used when CONFIG_CGROUP_MEM_RES_CTLR_KMEM=n with the semantics that it as in this patchset. It's much cleaner by making it 0x0 when disabled. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>