| Message ID | 20210423203811.1247508-3-rppt@kernel.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | mmzone.h: fix kernel-doc and simplify is_highmem_idx | expand |
On 4/24/21 2:08 AM, Mike Rapoport wrote: > From: Mike Rapoport <rppt@linux.ibm.com> > > There is a lot of historical ifdefery in is_highmem_idx() and its helper > zone_movable_is_highmem() that was required because of two different paths > for nodes and zones initialization that were selected at compile time. > > Until commit 3f08a302f533 ("mm: remove CONFIG_HAVE_MEMBLOCK_NODE_MAP > option") the movable_zone variable was only available for configurations > that had CONFIG_HAVE_MEMBLOCK_NODE_MAP enabled so the test in > zone_movable_is_highmem() used that variable only for such configurations. > For other configurations the test checked if the index of ZONE_MOVABLE was > greater by 1 than the index of ZONE_HIGMEM and then movable zone was > considered a highmem zone. Needless to say, ZONE_MOVABLE - 1 equals > ZONE_HIGMEM by definition when CONFIG_HIGHMEM=y. Right with CONFIG_HIGHMEM is enabled, ZONE_MOVABLE = ZONE_HIGHMEM + 1 holds always true from the very definition in enum zone_type { }. > > Commit 3f08a302f533 ("mm: remove CONFIG_HAVE_MEMBLOCK_NODE_MAP option") > made movable_zone variable always available. Since this variable is set to > ZONE_HIGHMEM if CONFIG_HIGHMEM is enabled and highmem zone is populated, it > is enough to check whether > > zone_idx == ZONE_MOVABLE && movable_zone == ZONE_HIGMEM Right. A small nit. s/HIGMEM/HIGHMEM > > to test if zone index points to a highmem zone. If the CONFIG_HIGHMEM is enabled but ZONE_HIGHMEM is not populated, then movable_node would point to a zone below ZONE_HIGHMEM and is_highmem_idx() would also return false. > > Remove zone_movable_is_highmem() that is not used anywhere except > is_highmem_idx() and use the test above in is_highmem_idx() instead. > > Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> > --- > include/linux/mmzone.h | 13 +------------ > 1 file changed, 1 insertion(+), 12 deletions(-) > > diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h > index 3b2205741048..6a1ac643b65e 100644 > --- a/include/linux/mmzone.h > +++ b/include/linux/mmzone.h > @@ -968,22 +968,11 @@ static inline void zone_set_nid(struct zone *zone, int nid) {} > > extern int movable_zone; > > -#ifdef CONFIG_HIGHMEM > -static inline int zone_movable_is_highmem(void) > -{ > -#ifdef CONFIG_NEED_MULTIPLE_NODES > - return movable_zone == ZONE_HIGHMEM; > -#else > - return (ZONE_MOVABLE - 1) == ZONE_HIGHMEM; > -#endif > -} > -#endif > - > static inline int is_highmem_idx(enum zone_type idx) > { > #ifdef CONFIG_HIGHMEM > return (idx == ZONE_HIGHMEM || > - (idx == ZONE_MOVABLE && zone_movable_is_highmem())); > + (idx == ZONE_MOVABLE && movable_zone == ZONE_HIGHMEM)); > #else > return 0; > #endif > LGTM. Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index 3b2205741048..6a1ac643b65e 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -968,22 +968,11 @@ static inline void zone_set_nid(struct zone *zone, int nid) {} extern int movable_zone; -#ifdef CONFIG_HIGHMEM -static inline int zone_movable_is_highmem(void) -{ -#ifdef CONFIG_NEED_MULTIPLE_NODES - return movable_zone == ZONE_HIGHMEM; -#else - return (ZONE_MOVABLE - 1) == ZONE_HIGHMEM; -#endif -} -#endif - static inline int is_highmem_idx(enum zone_type idx) { #ifdef CONFIG_HIGHMEM return (idx == ZONE_HIGHMEM || - (idx == ZONE_MOVABLE && zone_movable_is_highmem())); + (idx == ZONE_MOVABLE && movable_zone == ZONE_HIGHMEM)); #else return 0; #endif