In preparation for further changes, let's teach __free_pages_core()
about the differences of memory hotplug handling.
Move the memory hotplug specific handling from generic_online_page() to
__free_pages_core(), use adjust_managed_page_count() on the memory
hotplug path, and spell out why memory freed via memblock
cannot currently use adjust_managed_page_count().
Signed-off-by: David Hildenbrand <david@redhat.com>
---
mm/internal.h | 3 ++-
mm/kmsan/init.c | 2 +-
mm/memory_hotplug.c | 9 +--------
mm/mm_init.c | 4 ++--
mm/page_alloc.c | 17 +++++++++++++++--
5 files changed, 21 insertions(+), 14 deletions(-)
diff --git a/mm/internal.h b/mm/internal.h
index 12e95fdf61e90..3fdee779205ab 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -604,7 +604,8 @@ extern void __putback_isolated_page(struct page *page, unsigned int order,
int mt);
extern void memblock_free_pages(struct page *page, unsigned long pfn,
unsigned int order);
-extern void __free_pages_core(struct page *page, unsigned int order);
+extern void __free_pages_core(struct page *page, unsigned int order,
+ enum meminit_context);
/*
* This will have no effect, other than possibly generating a warning, if the
diff --git a/mm/kmsan/init.c b/mm/kmsan/init.c
index 3ac3b8921d36f..ca79636f858e5 100644
--- a/mm/kmsan/init.c
+++ b/mm/kmsan/init.c
@@ -172,7 +172,7 @@ static void do_collection(void)
shadow = smallstack_pop(&collect);
origin = smallstack_pop(&collect);
kmsan_setup_meta(page, shadow, origin, collect.order);
- __free_pages_core(page, collect.order);
+ __free_pages_core(page, collect.order, MEMINIT_EARLY);
}
}
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 171ad975c7cfd..27e3be75edcf7 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -630,14 +630,7 @@ EXPORT_SYMBOL_GPL(restore_online_page_callback);
void generic_online_page(struct page *page, unsigned int order)
{
- /*
- * Freeing the page with debug_pagealloc enabled will try to unmap it,
- * so we should map it first. This is better than introducing a special
- * case in page freeing fast path.
- */
- debug_pagealloc_map_pages(page, 1 << order);
- __free_pages_core(page, order);
- totalram_pages_add(1UL << order);
+ __free_pages_core(page, order, MEMINIT_HOTPLUG);
}
EXPORT_SYMBOL_GPL(generic_online_page);
diff --git a/mm/mm_init.c b/mm/mm_init.c
index 019193b0d8703..feb5b6e8c8875 100644
--- a/mm/mm_init.c
+++ b/mm/mm_init.c
@@ -1938,7 +1938,7 @@ static void __init deferred_free_range(unsigned long pfn,
for (i = 0; i < nr_pages; i++, page++, pfn++) {
if (pageblock_aligned(pfn))
set_pageblock_migratetype(page, MIGRATE_MOVABLE);
- __free_pages_core(page, 0);
+ __free_pages_core(page, 0, MEMINIT_EARLY);
}
}
@@ -2513,7 +2513,7 @@ void __init memblock_free_pages(struct page *page, unsigned long pfn,
}
}
- __free_pages_core(page, order);
+ __free_pages_core(page, order, MEMINIT_EARLY);
}
DEFINE_STATIC_KEY_MAYBE(CONFIG_INIT_ON_ALLOC_DEFAULT_ON, init_on_alloc);
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 2224965ada468..e0c8a8354be36 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1214,7 +1214,8 @@ static void __free_pages_ok(struct page *page, unsigned int order,
__count_vm_events(PGFREE, 1 << order);
}
-void __free_pages_core(struct page *page, unsigned int order)
+void __free_pages_core(struct page *page, unsigned int order,
+ enum meminit_context context)
{
unsigned int nr_pages = 1 << order;
struct page *p = page;
@@ -1234,7 +1235,19 @@ void __free_pages_core(struct page *page, unsigned int order)
__ClearPageReserved(p);
set_page_count(p, 0);
- atomic_long_add(nr_pages, &page_zone(page)->managed_pages);
+ if (IS_ENABLED(CONFIG_MEMORY_HOTPLUG) &&
+ unlikely(context == MEMINIT_HOTPLUG)) {
+ /*
+ * Freeing the page with debug_pagealloc enabled will try to
+ * unmap it; some archs don't like double-unmappings, so
+ * map it first.
+ */
+ debug_pagealloc_map_pages(page, nr_pages);
+ adjust_managed_page_count(page, nr_pages);
+ } else {
+ /* memblock adjusts totalram_pages() ahead of time. */
+ atomic_long_add(nr_pages, &page_zone(page)->managed_pages);
+ }
if (page_contains_unaccepted(page, order)) {
if (order == MAX_PAGE_ORDER && __free_unaccepted(page))
--
2.45.1On Fri, 2024-06-07 at 11:09 +0200, David Hildenbrand wrote: > In preparation for further changes, let's teach __free_pages_core() > about the differences of memory hotplug handling. > > Move the memory hotplug specific handling from generic_online_page() to > __free_pages_core(), use adjust_managed_page_count() on the memory > hotplug path, and spell out why memory freed via memblock > cannot currently use adjust_managed_page_count(). > > Signed-off-by: David Hildenbrand <david@redhat.com> > --- > mm/internal.h | 3 ++- > mm/kmsan/init.c | 2 +- > mm/memory_hotplug.c | 9 +-------- > mm/mm_init.c | 4 ++-- > mm/page_alloc.c | 17 +++++++++++++++-- > 5 files changed, 21 insertions(+), 14 deletions(-) > > diff --git a/mm/internal.h b/mm/internal.h > index 12e95fdf61e90..3fdee779205ab 100644 > --- a/mm/internal.h > +++ b/mm/internal.h > @@ -604,7 +604,8 @@ extern void __putback_isolated_page(struct page *page, unsigned int order, > int mt); > extern void memblock_free_pages(struct page *page, unsigned long pfn, > unsigned int order); > -extern void __free_pages_core(struct page *page, unsigned int order); > +extern void __free_pages_core(struct page *page, unsigned int order, > + enum meminit_context); Shouldn't the above be enum meminit_context context); > > /* > * This will have no effect, other than possibly generating a warning, if the Thanks. Tim
On 11.06.24 21:41, Tim Chen wrote: > On Fri, 2024-06-07 at 11:09 +0200, David Hildenbrand wrote: >> In preparation for further changes, let's teach __free_pages_core() >> about the differences of memory hotplug handling. >> >> Move the memory hotplug specific handling from generic_online_page() to >> __free_pages_core(), use adjust_managed_page_count() on the memory >> hotplug path, and spell out why memory freed via memblock >> cannot currently use adjust_managed_page_count(). >> >> Signed-off-by: David Hildenbrand <david@redhat.com> >> --- >> mm/internal.h | 3 ++- >> mm/kmsan/init.c | 2 +- >> mm/memory_hotplug.c | 9 +-------- >> mm/mm_init.c | 4 ++-- >> mm/page_alloc.c | 17 +++++++++++++++-- >> 5 files changed, 21 insertions(+), 14 deletions(-) >> >> diff --git a/mm/internal.h b/mm/internal.h >> index 12e95fdf61e90..3fdee779205ab 100644 >> --- a/mm/internal.h >> +++ b/mm/internal.h >> @@ -604,7 +604,8 @@ extern void __putback_isolated_page(struct page *page, unsigned int order, >> int mt); >> extern void memblock_free_pages(struct page *page, unsigned long pfn, >> unsigned int order); >> -extern void __free_pages_core(struct page *page, unsigned int order); >> +extern void __free_pages_core(struct page *page, unsigned int order, >> + enum meminit_context); > > Shouldn't the above be > enum meminit_context context); Although C allows parameters without names in declarations, this was unintended. Thanks! -- Cheers, David / dhildenb
On 07.06.24 11:09, David Hildenbrand wrote:
> In preparation for further changes, let's teach __free_pages_core()
> about the differences of memory hotplug handling.
>
> Move the memory hotplug specific handling from generic_online_page() to
> __free_pages_core(), use adjust_managed_page_count() on the memory
> hotplug path, and spell out why memory freed via memblock
> cannot currently use adjust_managed_page_count().
>
> Signed-off-by: David Hildenbrand <david@redhat.com>
> ---
@Andrew, can you squash the following?
From 0a7921cf21cacf178ca7485da0138fc38a97a28e Mon Sep 17 00:00:00 2001
From: David Hildenbrand <david@redhat.com>
Date: Tue, 11 Jun 2024 12:05:09 +0200
Subject: [PATCH] fixup: mm/highmem: make nr_free_highpages() return "unsigned
long"
Fixup the memblock comment.
Signed-off-by: David Hildenbrand <david@redhat.com>
---
mm/page_alloc.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index e0c8a8354be36..fc53f96db58a2 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1245,7 +1245,7 @@ void __free_pages_core(struct page *page, unsigned int order,
debug_pagealloc_map_pages(page, nr_pages);
adjust_managed_page_count(page, nr_pages);
} else {
- /* memblock adjusts totalram_pages() ahead of time. */
+ /* memblock adjusts totalram_pages() manually. */
atomic_long_add(nr_pages, &page_zone(page)->managed_pages);
}
--
2.45.2
--
Cheers,
David / dhildenb
On Tue, 11 Jun 2024 12:06:56 +0200 David Hildenbrand <david@redhat.com> wrote: > On 07.06.24 11:09, David Hildenbrand wrote: > > In preparation for further changes, let's teach __free_pages_core() > > about the differences of memory hotplug handling. > > > > Move the memory hotplug specific handling from generic_online_page() to > > __free_pages_core(), use adjust_managed_page_count() on the memory > > hotplug path, and spell out why memory freed via memblock > > cannot currently use adjust_managed_page_count(). > > > > Signed-off-by: David Hildenbrand <david@redhat.com> > > --- > > @Andrew, can you squash the following? Sure. I queued it against "mm: pass meminit_context to __free_pages_core()", not against > Subject: [PATCH] fixup: mm/highmem: make nr_free_highpages() return "unsigned > long"
On 11.06.24 21:19, Andrew Morton wrote: > On Tue, 11 Jun 2024 12:06:56 +0200 David Hildenbrand <david@redhat.com> wrote: > >> On 07.06.24 11:09, David Hildenbrand wrote: >>> In preparation for further changes, let's teach __free_pages_core() >>> about the differences of memory hotplug handling. >>> >>> Move the memory hotplug specific handling from generic_online_page() to >>> __free_pages_core(), use adjust_managed_page_count() on the memory >>> hotplug path, and spell out why memory freed via memblock >>> cannot currently use adjust_managed_page_count(). >>> >>> Signed-off-by: David Hildenbrand <david@redhat.com> >>> --- >> >> @Andrew, can you squash the following? > > Sure. > > I queued it against "mm: pass meminit_context to __free_pages_core()", > not against > >> Subject: [PATCH] fixup: mm/highmem: make nr_free_highpages() return "unsigned >> long" > Can you squash the following as well? (hopefully the last fixup, otherwise I might just resend a v2) From 53c8c5834e638b2ae5e2a34fa7d49ce0dcf25192 Mon Sep 17 00:00:00 2001 From: David Hildenbrand <david@redhat.com> Date: Wed, 12 Jun 2024 20:31:07 +0200 Subject: [PATCH] fixup: mm: pass meminit_context to __free_pages_core() Let's add the parameter name also in the declaration. Signed-off-by: David Hildenbrand <david@redhat.com> --- mm/internal.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/internal.h b/mm/internal.h index 14bab8a41baf6..254dd907bf9a2 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -605,7 +605,7 @@ extern void __putback_isolated_page(struct page *page, unsigned int order, extern void memblock_free_pages(struct page *page, unsigned long pfn, unsigned int order); extern void __free_pages_core(struct page *page, unsigned int order, - enum meminit_context); + enum meminit_context context); /* * This will have no effect, other than possibly generating a warning, if the -- 2.45.2 -- Cheers, David / dhildenb
On 11.06.24 21:19, Andrew Morton wrote: > On Tue, 11 Jun 2024 12:06:56 +0200 David Hildenbrand <david@redhat.com> wrote: > >> On 07.06.24 11:09, David Hildenbrand wrote: >>> In preparation for further changes, let's teach __free_pages_core() >>> about the differences of memory hotplug handling. >>> >>> Move the memory hotplug specific handling from generic_online_page() to >>> __free_pages_core(), use adjust_managed_page_count() on the memory >>> hotplug path, and spell out why memory freed via memblock >>> cannot currently use adjust_managed_page_count(). >>> >>> Signed-off-by: David Hildenbrand <david@redhat.com> >>> --- >> >> @Andrew, can you squash the following? > > Sure. > > I queued it against "mm: pass meminit_context to __free_pages_core()", > not against Ah yes, sorry. Thanks! -- Cheers, David / dhildenb
On Fri, Jun 07, 2024 at 11:09:36AM +0200, David Hildenbrand wrote:
> In preparation for further changes, let's teach __free_pages_core()
> about the differences of memory hotplug handling.
>
> Move the memory hotplug specific handling from generic_online_page() to
> __free_pages_core(), use adjust_managed_page_count() on the memory
> hotplug path, and spell out why memory freed via memblock
> cannot currently use adjust_managed_page_count().
>
> Signed-off-by: David Hildenbrand <david@redhat.com>
All looks good but I am puzzled with something.
> + } else {
> + /* memblock adjusts totalram_pages() ahead of time. */
> + atomic_long_add(nr_pages, &page_zone(page)->managed_pages);
> + }
You say that memblock adjusts totalram_pages ahead of time, and I guess
you mean in memblock_free_all()
pages = free_low_memory_core_early()
totalram_pages_add(pages);
but that is not ahead, it looks like it is upading __after__ sending
them to buddy?
--
Oscar Salvador
SUSE Labs
On 10.06.24 06:03, Oscar Salvador wrote:
> On Fri, Jun 07, 2024 at 11:09:36AM +0200, David Hildenbrand wrote:
>> In preparation for further changes, let's teach __free_pages_core()
>> about the differences of memory hotplug handling.
>>
>> Move the memory hotplug specific handling from generic_online_page() to
>> __free_pages_core(), use adjust_managed_page_count() on the memory
>> hotplug path, and spell out why memory freed via memblock
>> cannot currently use adjust_managed_page_count().
>>
>> Signed-off-by: David Hildenbrand <david@redhat.com>
>
> All looks good but I am puzzled with something.
>
>> + } else {
>> + /* memblock adjusts totalram_pages() ahead of time. */
>> + atomic_long_add(nr_pages, &page_zone(page)->managed_pages);
>> + }
>
> You say that memblock adjusts totalram_pages ahead of time, and I guess
> you mean in memblock_free_all()
And memblock_free_late(), which uses atomic_long_inc().
>
> pages = free_low_memory_core_early()
> totalram_pages_add(pages);
>
> but that is not ahead, it looks like it is upading __after__ sending
> them to buddy?
Right (it's suboptimal, but not really problematic so far. Hopefully Wei
can clean it up and move it in here as well)
For the time being
"/* memblock adjusts totalram_pages() manually. */"
?
Thanks!
--
Cheers,
David / dhildenb
On Mon, Jun 10, 2024 at 10:38:05AM +0200, David Hildenbrand wrote:
> On 10.06.24 06:03, Oscar Salvador wrote:
> > On Fri, Jun 07, 2024 at 11:09:36AM +0200, David Hildenbrand wrote:
> > > In preparation for further changes, let's teach __free_pages_core()
> > > about the differences of memory hotplug handling.
> > >
> > > Move the memory hotplug specific handling from generic_online_page() to
> > > __free_pages_core(), use adjust_managed_page_count() on the memory
> > > hotplug path, and spell out why memory freed via memblock
> > > cannot currently use adjust_managed_page_count().
> > >
> > > Signed-off-by: David Hildenbrand <david@redhat.com>
> >
> > All looks good but I am puzzled with something.
> >
> > > + } else {
> > > + /* memblock adjusts totalram_pages() ahead of time. */
> > > + atomic_long_add(nr_pages, &page_zone(page)->managed_pages);
> > > + }
> >
> > You say that memblock adjusts totalram_pages ahead of time, and I guess
> > you mean in memblock_free_all()
>
> And memblock_free_late(), which uses atomic_long_inc().
Ah yes.
> Right (it's suboptimal, but not really problematic so far. Hopefully Wei can
> clean it up and move it in here as well)
That would be great.
> For the time being
>
> "/* memblock adjusts totalram_pages() manually. */"
Yes, I think that is better ;-)
Thanks!
--
Oscar Salvador
SUSE Labs
On 07.06.24 11:09, David Hildenbrand wrote:
> In preparation for further changes, let's teach __free_pages_core()
> about the differences of memory hotplug handling.
>
> Move the memory hotplug specific handling from generic_online_page() to
> __free_pages_core(), use adjust_managed_page_count() on the memory
> hotplug path, and spell out why memory freed via memblock
> cannot currently use adjust_managed_page_count().
>
> Signed-off-by: David Hildenbrand <david@redhat.com>
> ---
> mm/internal.h | 3 ++-
> mm/kmsan/init.c | 2 +-
> mm/memory_hotplug.c | 9 +--------
> mm/mm_init.c | 4 ++--
> mm/page_alloc.c | 17 +++++++++++++++--
> 5 files changed, 21 insertions(+), 14 deletions(-)
>
> diff --git a/mm/internal.h b/mm/internal.h
> index 12e95fdf61e90..3fdee779205ab 100644
> --- a/mm/internal.h
> +++ b/mm/internal.h
> @@ -604,7 +604,8 @@ extern void __putback_isolated_page(struct page *page, unsigned int order,
> int mt);
> extern void memblock_free_pages(struct page *page, unsigned long pfn,
> unsigned int order);
> -extern void __free_pages_core(struct page *page, unsigned int order);
> +extern void __free_pages_core(struct page *page, unsigned int order,
> + enum meminit_context);
>
> /*
> * This will have no effect, other than possibly generating a warning, if the
> diff --git a/mm/kmsan/init.c b/mm/kmsan/init.c
> index 3ac3b8921d36f..ca79636f858e5 100644
> --- a/mm/kmsan/init.c
> +++ b/mm/kmsan/init.c
> @@ -172,7 +172,7 @@ static void do_collection(void)
> shadow = smallstack_pop(&collect);
> origin = smallstack_pop(&collect);
> kmsan_setup_meta(page, shadow, origin, collect.order);
> - __free_pages_core(page, collect.order);
> + __free_pages_core(page, collect.order, MEMINIT_EARLY);
> }
> }
>
> diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
> index 171ad975c7cfd..27e3be75edcf7 100644
> --- a/mm/memory_hotplug.c
> +++ b/mm/memory_hotplug.c
> @@ -630,14 +630,7 @@ EXPORT_SYMBOL_GPL(restore_online_page_callback);
>
> void generic_online_page(struct page *page, unsigned int order)
> {
> - /*
> - * Freeing the page with debug_pagealloc enabled will try to unmap it,
> - * so we should map it first. This is better than introducing a special
> - * case in page freeing fast path.
> - */
> - debug_pagealloc_map_pages(page, 1 << order);
> - __free_pages_core(page, order);
> - totalram_pages_add(1UL << order);
> + __free_pages_core(page, order, MEMINIT_HOTPLUG);
> }
> EXPORT_SYMBOL_GPL(generic_online_page);
>
> diff --git a/mm/mm_init.c b/mm/mm_init.c
> index 019193b0d8703..feb5b6e8c8875 100644
> --- a/mm/mm_init.c
> +++ b/mm/mm_init.c
> @@ -1938,7 +1938,7 @@ static void __init deferred_free_range(unsigned long pfn,
> for (i = 0; i < nr_pages; i++, page++, pfn++) {
> if (pageblock_aligned(pfn))
> set_pageblock_migratetype(page, MIGRATE_MOVABLE);
> - __free_pages_core(page, 0);
> + __free_pages_core(page, 0, MEMINIT_EARLY);
> }
> }
The build bot just reminded me that I missed another case in this function:
(CONFIG_DEFERRED_STRUCT_PAGE_INIT)
diff --git a/mm/mm_init.c b/mm/mm_init.c
index feb5b6e8c8875..5a0752261a795 100644
--- a/mm/mm_init.c
+++ b/mm/mm_init.c
@@ -1928,7 +1928,7 @@ static void __init deferred_free_range(unsigned long pfn,
if (nr_pages == MAX_ORDER_NR_PAGES && IS_MAX_ORDER_ALIGNED(pfn)) {
for (i = 0; i < nr_pages; i += pageblock_nr_pages)
set_pageblock_migratetype(page + i, MIGRATE_MOVABLE);
- __free_pages_core(page, MAX_PAGE_ORDER);
+ __free_pages_core(page, MAX_PAGE_ORDER, MEMINIT_EARLY);
return;
}
--
Cheers,
David / dhildenb
© 2016 - 2026 Red Hat, Inc.