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mm/mm_init.c: simplify logic of deferred_[init|free]_pages

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Function deferred_[init|free]_pages are only used in
deferred_init_maxorder(), which makes sure the range to init/free is
within MAX_ORDER_NR_PAGES size.

With this knowledge, we can simplify these two functions. Since

  * only the first pfn could be IS_MAX_ORDER_ALIGNED()

Also since the range passed to deferred_[init|free]_pages is always from
memblock.memory for those we have already allocated memmap to cover,
pfn_valid() always return true.  Then we can remove related check.

[richard.weiyang@gmail.com: adjust function declaration indention per David]
  Link: https://lkml.kernel.org/r/20240613114525.27528-1-richard.weiyang@gmail.com
Link: https://lkml.kernel.org/r/20240612020421.31975-1-richard.weiyang@gmail.com
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Reviewed-by: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Wei Yang 2024-06-12 02:04:21 +00:00 committed by Andrew Morton
parent e5d896703d
commit 972b89c1f0
1 changed files with 8 additions and 56 deletions
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64
mm/mm_init.c
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@ -1916,8 +1916,8 @@ unsigned long __init node_map_pfn_alignment(void)
}
#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
static void __init deferred_free_range(unsigned long pfn,
unsigned long nr_pages)
static void __init deferred_free_pages(unsigned long pfn,
unsigned long nr_pages)
{
struct page *page;
unsigned long i;
@ -1955,69 +1955,21 @@ static inline void __init pgdat_init_report_one_done(void)
complete(&pgdat_init_all_done_comp);
}
/*
* Returns true if page needs to be initialized or freed to buddy allocator.
*
* We check if a current MAX_PAGE_ORDER block is valid by only checking the
* validity of the head pfn.
*/
static inline bool __init deferred_pfn_valid(unsigned long pfn)
{
if (IS_MAX_ORDER_ALIGNED(pfn) && !pfn_valid(pfn))
return false;
return true;
}
/*
* Free pages to buddy allocator. Try to free aligned pages in
* MAX_ORDER_NR_PAGES sizes.
*/
static void __init deferred_free_pages(unsigned long pfn,
unsigned long end_pfn)
{
unsigned long nr_free = 0;
for (; pfn < end_pfn; pfn++) {
if (!deferred_pfn_valid(pfn)) {
deferred_free_range(pfn - nr_free, nr_free);
nr_free = 0;
} else if (IS_MAX_ORDER_ALIGNED(pfn)) {
deferred_free_range(pfn - nr_free, nr_free);
nr_free = 1;
} else {
nr_free++;
}
}
/* Free the last block of pages to allocator */
deferred_free_range(pfn - nr_free, nr_free);
}
/*
* Initialize struct pages. We minimize pfn page lookups and scheduler checks
* by performing it only once every MAX_ORDER_NR_PAGES.
* Return number of pages initialized.
*/
static unsigned long __init deferred_init_pages(struct zone *zone,
unsigned long pfn,
unsigned long end_pfn)
static unsigned long __init deferred_init_pages(struct zone *zone,
unsigned long pfn, unsigned long end_pfn)
{
int nid = zone_to_nid(zone);
unsigned long nr_pages = 0;
unsigned long nr_pages = end_pfn - pfn;
int zid = zone_idx(zone);
struct page *page = NULL;
struct page *page = pfn_to_page(pfn);
for (; pfn < end_pfn; pfn++) {
if (!deferred_pfn_valid(pfn)) {
page = NULL;
continue;
} else if (!page || IS_MAX_ORDER_ALIGNED(pfn)) {
page = pfn_to_page(pfn);
} else {
page++;
}
for (; pfn < end_pfn; pfn++, page++)
__init_single_page(page, pfn, zid, nid);
nr_pages++;
}
return nr_pages;
}
@ -2096,7 +2048,7 @@ deferred_init_maxorder(u64 *i, struct zone *zone, unsigned long *start_pfn,
break;
t = min(mo_pfn, epfn);
deferred_free_pages(spfn, t);
deferred_free_pages(spfn, t - spfn);
if (mo_pfn <= epfn)
break;