On Wed, 4 Feb 2015 13:54:31 +0200 "Kirill A. Shutemov" <kirill.shutemov@xxxxxxxxxxxxxxx> wrote: > After commit 944d9fec8d7a we can allocate 1G pages runtime if CMA is > enabled. > > Let's register 1G pages into hugetlb even if user hasn't requested them > explicitly at boot time with hugepagesz=1G. > > Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx> > Cc: Luiz Capitulino <lcapitulino@xxxxxxxxxx> > Cc: Naoya Horiguchi <n-horiguchi@xxxxxxxxxxxxx> > Cc: Andi Kleen <ak@xxxxxxxxxxxxxxx> > Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> > Cc: Ingo Molnar <mingo@xxxxxxxxxx> > Cc: "H. Peter Anvin" <hpa@xxxxxxxxx> > --- > arch/x86/mm/hugetlbpage.c | 11 +++++++++++ > 1 file changed, 11 insertions(+) > > diff --git a/arch/x86/mm/hugetlbpage.c b/arch/x86/mm/hugetlbpage.c > index 9161f764121e..42982b26e32b 100644 > --- a/arch/x86/mm/hugetlbpage.c > +++ b/arch/x86/mm/hugetlbpage.c > @@ -172,4 +172,15 @@ static __init int setup_hugepagesz(char *opt) > return 1; > } > __setup("hugepagesz=", setup_hugepagesz); > + > +#ifdef CONFIG_CMA > +static __init int gigantic_pages_init(void) > +{ > + /* With CMA we can allocate gigantic pages at runtime */ > + if (cpu_has_gbpages && !size_to_hstate(1UL << PUD_SHIFT)) > + hugetlb_add_hstate(PUD_SHIFT - PAGE_SHIFT); > + return 0; > +} > +arch_initcall(gigantic_pages_init); > +#endif > #endif Very nice! I was thinking about this for a long time but I don't think my implementation would be that simple: Reviewed-by: Luiz Capitulino <lcapitulino@xxxxxxxxxx> -- 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>