diff options
| author | Liam R. Howlett <Liam.Howlett@Oracle.com> | 2022-05-31 09:20:51 -0400 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2022-10-20 21:27:23 -0700 |
| commit | df48a5f7a3bbac6a700026b554922943ecee1fb0 (patch) | |
| tree | d210bb01c9e8cdf4070ca9d3b61db8830c966349 | |
| parent | 08ac85521cb2e26f25b885492180815ce8eaf4b7 (diff) | |
mm/page_alloc: reduce potential fragmentation in make_alloc_exact()
Try to avoid using the left over split page on the next request for a page
by calling __free_pages_ok() with FPI_TO_TAIL. This increases the
potential of defragmenting memory when it's used for a short period of
time.
Link: https://lkml.kernel.org/r/20220531185626.yvlmymbxyoe5vags@revolver
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Suggested-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
| -rw-r--r-- | mm/page_alloc.c | 20 |
1 files changed, 12 insertions, 8 deletions
diff --git a/mm/page_alloc.c b/mm/page_alloc.c index e20ade858e71..b5a6c815ae28 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -5784,14 +5784,18 @@ static void *make_alloc_exact(unsigned long addr, unsigned int order, size_t size) { if (addr) { - unsigned long alloc_end = addr + (PAGE_SIZE << order); - unsigned long used = addr + PAGE_ALIGN(size); - - split_page(virt_to_page((void *)addr), order); - while (used < alloc_end) { - free_page(used); - used += PAGE_SIZE; - } + unsigned long nr = DIV_ROUND_UP(size, PAGE_SIZE); + struct page *page = virt_to_page((void *)addr); + struct page *last = page + nr; + + split_page_owner(page, 1 << order); + split_page_memcg(page, 1 << order); + while (page < --last) + set_page_refcounted(last); + + last = page + (1UL << order); + for (page += nr; page < last; page++) + __free_pages_ok(page, 0, FPI_TO_TAIL); } return (void *)addr; } |