On Fri, 2021-07-02 at 16:11 +0300, Mike Rapoport wrote: > On Wed, Jun 30, 2021 at 05:23:09PM +0800, Miles Chen wrote: > > clarify pgdat_to_phys() by wrapping pgdat_to_phys > > with CONFIG_NUMA. (the same config as contig_page_data) > > > > No functional change intended. > > > > Comment from Mark [1]: > > " > > ... and I reckon it'd be clearer and more robust to define > > pgdat_to_phys() in the same ifdefs as contig_page_data so > > that these, stay in-sync. e.g. have: > > > > | #ifdef CONFIG_NUMA > > | #define pgdat_to_phys(x) virt_to_phys(x) > > | #else /* CONFIG_NUMA */ > > | > > | extern struct pglist_data contig_page_data; > > | ... > > | #define pgdat_to_phys(x) __pa_symbol(&contig_page_data) > > | > > | #endif /* CONIFIG_NUMA */ > > " > > > > [1] https://lore.kernel.org/linux-arm-kernel/20210615131902.GB47121@C02TD0UTHF1T.local/ > > > > Cc: Mark Rutland <mark.rutland@xxxxxxx> > > Signed-off-by: Miles Chen <miles.chen@xxxxxxxxxxxx> > > --- > > mm/sparse.c | 17 +++++++++-------- > > 1 file changed, 9 insertions(+), 8 deletions(-) > > > > diff --git a/mm/sparse.c b/mm/sparse.c > > index 7272f7a1449d..62c21ec28e33 100644 > > --- a/mm/sparse.c > > +++ b/mm/sparse.c > > @@ -344,14 +344,15 @@ size_t mem_section_usage_size(void) > > return sizeof(struct mem_section_usage) + usemap_size(); > > } > > > > -static inline phys_addr_t pgdat_to_phys(struct pglist_data *pgdat) > > -{ > > -#ifndef CONFIG_NUMA > > - return __pa_symbol(pgdat); > > -#else > > - return __pa(pgdat); > > -#endif > > -} > > +#ifdef CONFIG_NUMA > > +#define pgdat_to_phys(pgdat) __pa(pgdat) > > +#else /* CONFIG_NUMA */ > > +/* > > + * When !CONFIG_NUMA, we only expect pgdat == &contig_page_data, > > + * and use __pa_symbol(). > > + */ > > +#define pgdat_to_phys(pgdat) __pa_symbol(pgdat) > > +#endif /* CONFIG_NUMA */ > > I'm not sure a macro is better than a static inline. > > Maybe we'd want to warn if pgdat passed to pgtat_to_phys() is not > &contig_page_data, e.g something like > > static inline phys_addr_t pgdat_to_phys(struct pglist_data *pgdat) > { > if (!IS_ENABLED(CONFIG_NUMA)) { > if (pgdat == &contig_page_data) > return __pa_symbol(&contig_page_data); > else > pr_warn("Unexpected pglist_data pointer!\n"); > } > > return __pa(pgdat); > } Sorry for my late response. Thanks for the guide. It looks better this way.I will submit patch v2. > > > #ifdef CONFIG_MEMORY_HOTREMOVE > > static struct mem_section_usage * __init > > -- > > 2.18.0 > > >
