Can we get rid of the highmem ifdef in adjust_managed_page_count()?
Likely yes: we don't have that many totalhigh_pages() users, and they
all don't seem to be very performance critical.
So let's implement totalhigh_pages() like nr_free_highpages(),
collecting information from all zones. This is now similar to what we do
in si_meminfo_node() to collect the per-node highmem page count.
In the common case (single node, 3-4 zones), we really shouldn't care.
We could optimize a bit further (only walk ZONE_HIGHMEM and ZONE_MOVABLE
if required), but there doesn't seem a real need for that.
Signed-off-by: David Hildenbrand <david@redhat.com>
---
include/linux/highmem-internal.h | 9 ++-------
mm/highmem.c | 16 +++++++++++++---
mm/page_alloc.c | 4 ----
3 files changed, 15 insertions(+), 14 deletions(-)
diff --git a/include/linux/highmem-internal.h b/include/linux/highmem-internal.h
index a3028e400a9c6..65f865fbbac04 100644
--- a/include/linux/highmem-internal.h
+++ b/include/linux/highmem-internal.h
@@ -132,7 +132,7 @@ static inline void __kunmap_atomic(const void *addr)
}
unsigned int __nr_free_highpages(void);
-extern atomic_long_t _totalhigh_pages;
+unsigned long __totalhigh_pages(void);
static inline unsigned int nr_free_highpages(void)
{
@@ -141,12 +141,7 @@ static inline unsigned int nr_free_highpages(void)
static inline unsigned long totalhigh_pages(void)
{
- return (unsigned long)atomic_long_read(&_totalhigh_pages);
-}
-
-static inline void totalhigh_pages_add(long count)
-{
- atomic_long_add(count, &_totalhigh_pages);
+ return __totalhigh_pages();
}
static inline bool is_kmap_addr(const void *x)
diff --git a/mm/highmem.c b/mm/highmem.c
index bd48ba445dd41..3c4e9f8c26dcd 100644
--- a/mm/highmem.c
+++ b/mm/highmem.c
@@ -111,9 +111,6 @@ static inline wait_queue_head_t *get_pkmap_wait_queue_head(unsigned int color)
}
#endif
-atomic_long_t _totalhigh_pages __read_mostly;
-EXPORT_SYMBOL(_totalhigh_pages);
-
unsigned int __nr_free_highpages(void)
{
struct zone *zone;
@@ -127,6 +124,19 @@ unsigned int __nr_free_highpages(void)
return pages;
}
+unsigned long __totalhigh_pages(void)
+{
+ unsigned long pages = 0;
+ struct zone *zone;
+
+ for_each_populated_zone(zone) {
+ if (is_highmem(zone))
+ pages += zone_managed_pages(zone);
+ }
+
+ return pages;
+}
+
static int pkmap_count[LAST_PKMAP];
static __cacheline_aligned_in_smp DEFINE_SPINLOCK(kmap_lock);
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index fc98082a9cf9c..2224965ada468 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -5794,10 +5794,6 @@ void adjust_managed_page_count(struct page *page, long count)
{
atomic_long_add(count, &page_zone(page)->managed_pages);
totalram_pages_add(count);
-#ifdef CONFIG_HIGHMEM
- if (PageHighMem(page))
- totalhigh_pages_add(count);
-#endif
}
EXPORT_SYMBOL(adjust_managed_page_count);
--
2.45.1On Fri, Jun 07, 2024 at 10:37:10AM +0200, David Hildenbrand wrote: > Can we get rid of the highmem ifdef in adjust_managed_page_count()? > Likely yes: we don't have that many totalhigh_pages() users, and they > all don't seem to be very performance critical. > > So let's implement totalhigh_pages() like nr_free_highpages(), > collecting information from all zones. This is now similar to what we do > in si_meminfo_node() to collect the per-node highmem page count. > > In the common case (single node, 3-4 zones), we really shouldn't care. > We could optimize a bit further (only walk ZONE_HIGHMEM and ZONE_MOVABLE > if required), but there doesn't seem a real need for that. > > Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> -- Oscar Salvador SUSE Labs
On Fri, Jun 07, 2024 at 10:37:10AM +0200, David Hildenbrand wrote:
>Can we get rid of the highmem ifdef in adjust_managed_page_count()?
>Likely yes: we don't have that many totalhigh_pages() users, and they
>all don't seem to be very performance critical.
>
>So let's implement totalhigh_pages() like nr_free_highpages(),
>collecting information from all zones. This is now similar to what we do
>in si_meminfo_node() to collect the per-node highmem page count.
>
>In the common case (single node, 3-4 zones), we really shouldn't care.
>We could optimize a bit further (only walk ZONE_HIGHMEM and ZONE_MOVABLE
>if required), but there doesn't seem a real need for that.
>
>Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Wei Yang <richard.weiyang@gmail.com>
>---
> include/linux/highmem-internal.h | 9 ++-------
> mm/highmem.c | 16 +++++++++++++---
> mm/page_alloc.c | 4 ----
> 3 files changed, 15 insertions(+), 14 deletions(-)
>
>diff --git a/include/linux/highmem-internal.h b/include/linux/highmem-internal.h
>index a3028e400a9c6..65f865fbbac04 100644
>--- a/include/linux/highmem-internal.h
>+++ b/include/linux/highmem-internal.h
>@@ -132,7 +132,7 @@ static inline void __kunmap_atomic(const void *addr)
> }
>
> unsigned int __nr_free_highpages(void);
>-extern atomic_long_t _totalhigh_pages;
>+unsigned long __totalhigh_pages(void);
>
> static inline unsigned int nr_free_highpages(void)
> {
>@@ -141,12 +141,7 @@ static inline unsigned int nr_free_highpages(void)
>
> static inline unsigned long totalhigh_pages(void)
> {
>- return (unsigned long)atomic_long_read(&_totalhigh_pages);
>-}
>-
>-static inline void totalhigh_pages_add(long count)
>-{
>- atomic_long_add(count, &_totalhigh_pages);
>+ return __totalhigh_pages();
> }
>
> static inline bool is_kmap_addr(const void *x)
>diff --git a/mm/highmem.c b/mm/highmem.c
>index bd48ba445dd41..3c4e9f8c26dcd 100644
>--- a/mm/highmem.c
>+++ b/mm/highmem.c
>@@ -111,9 +111,6 @@ static inline wait_queue_head_t *get_pkmap_wait_queue_head(unsigned int color)
> }
> #endif
>
>-atomic_long_t _totalhigh_pages __read_mostly;
>-EXPORT_SYMBOL(_totalhigh_pages);
>-
> unsigned int __nr_free_highpages(void)
> {
> struct zone *zone;
>@@ -127,6 +124,19 @@ unsigned int __nr_free_highpages(void)
> return pages;
> }
>
>+unsigned long __totalhigh_pages(void)
>+{
>+ unsigned long pages = 0;
>+ struct zone *zone;
>+
>+ for_each_populated_zone(zone) {
>+ if (is_highmem(zone))
>+ pages += zone_managed_pages(zone);
>+ }
>+
>+ return pages;
>+}
>+
> static int pkmap_count[LAST_PKMAP];
> static __cacheline_aligned_in_smp DEFINE_SPINLOCK(kmap_lock);
>
>diff --git a/mm/page_alloc.c b/mm/page_alloc.c
>index fc98082a9cf9c..2224965ada468 100644
>--- a/mm/page_alloc.c
>+++ b/mm/page_alloc.c
>@@ -5794,10 +5794,6 @@ void adjust_managed_page_count(struct page *page, long count)
> {
> atomic_long_add(count, &page_zone(page)->managed_pages);
> totalram_pages_add(count);
>-#ifdef CONFIG_HIGHMEM
>- if (PageHighMem(page))
>- totalhigh_pages_add(count);
>-#endif
> }
> EXPORT_SYMBOL(adjust_managed_page_count);
>
>--
>2.45.1
--
Wei Yang
Help you, Help me
On 07.06.24 10:37, David Hildenbrand wrote:
> Can we get rid of the highmem ifdef in adjust_managed_page_count()?
> Likely yes: we don't have that many totalhigh_pages() users, and they
> all don't seem to be very performance critical.
>
> So let's implement totalhigh_pages() like nr_free_highpages(),
> collecting information from all zones. This is now similar to what we do
> in si_meminfo_node() to collect the per-node highmem page count.
>
> In the common case (single node, 3-4 zones), we really shouldn't care.
> We could optimize a bit further (only walk ZONE_HIGHMEM and ZONE_MOVABLE
> if required), but there doesn't seem a real need for that.
>
> Signed-off-by: David Hildenbrand <david@redhat.com>
> ---
> include/linux/highmem-internal.h | 9 ++-------
> mm/highmem.c | 16 +++++++++++++---
> mm/page_alloc.c | 4 ----
> 3 files changed, 15 insertions(+), 14 deletions(-)
>
> diff --git a/include/linux/highmem-internal.h b/include/linux/highmem-internal.h
> index a3028e400a9c6..65f865fbbac04 100644
> --- a/include/linux/highmem-internal.h
> +++ b/include/linux/highmem-internal.h
> @@ -132,7 +132,7 @@ static inline void __kunmap_atomic(const void *addr)
> }
>
> unsigned int __nr_free_highpages(void);
> -extern atomic_long_t _totalhigh_pages;
> +unsigned long __totalhigh_pages(void);
>
> static inline unsigned int nr_free_highpages(void)
> {
> @@ -141,12 +141,7 @@ static inline unsigned int nr_free_highpages(void)
>
> static inline unsigned long totalhigh_pages(void)
> {
> - return (unsigned long)atomic_long_read(&_totalhigh_pages);
> -}
> -
> -static inline void totalhigh_pages_add(long count)
> -{
> - atomic_long_add(count, &_totalhigh_pages);
> + return __totalhigh_pages();
> }
>
> static inline bool is_kmap_addr(const void *x)
> diff --git a/mm/highmem.c b/mm/highmem.c
> index bd48ba445dd41..3c4e9f8c26dcd 100644
> --- a/mm/highmem.c
> +++ b/mm/highmem.c
> @@ -111,9 +111,6 @@ static inline wait_queue_head_t *get_pkmap_wait_queue_head(unsigned int color)
> }
> #endif
>
> -atomic_long_t _totalhigh_pages __read_mostly;
> -EXPORT_SYMBOL(_totalhigh_pages);
> -
> unsigned int __nr_free_highpages(void)
> {
> struct zone *zone;
> @@ -127,6 +124,19 @@ unsigned int __nr_free_highpages(void)
> return pages;
> }
>
> +unsigned long __totalhigh_pages(void)
> +{
> + unsigned long pages = 0;
> + struct zone *zone;
> +
> + for_each_populated_zone(zone) {
> + if (is_highmem(zone))
> + pages += zone_managed_pages(zone);
> + }
> +
> + return pages;
> +}
> +
Another (later than usual, but better late than never) build bot complaint:
diff --git a/mm/highmem.c b/mm/highmem.c
index 3c4e9f8c26dcd..b14771fb05ed1 100644
--- a/mm/highmem.c
+++ b/mm/highmem.c
@@ -136,6 +136,7 @@ unsigned long __totalhigh_pages(void)
return pages;
}
+EXPORT_SYMBOL(__totalhigh_pages);
static int pkmap_count[LAST_PKMAP];
static __cacheline_aligned_in_smp DEFINE_SPINLOCK(kmap_lock);
--
Cheers,
David / dhildenb
© 2016 - 2026 Red Hat, Inc.