[PATCH] mm: memory: move mem_cgroup_charge() into alloc_anon_folio()

From: Kefeng Wang
Date: Tue Jan 16 2024 - 02:14:58 EST


In order to allocate as much as possible of large folio, move
the mem charge into alloc_anon_folio() and try the next order
if mem_cgroup_charge() fails, also we change the GFP_KERNEL
to gfp to be consistent with PMD THP.

Signed-off-by: Kefeng Wang <wangkefeng.wang@xxxxxxxxxx>
---
mm/memory.c | 14 +++++++-------
1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/mm/memory.c b/mm/memory.c
index 5e88d5379127..2e31a407e6f9 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -4206,15 +4206,21 @@ static struct folio *alloc_anon_folio(struct vm_fault *vmf)
addr = ALIGN_DOWN(vmf->address, PAGE_SIZE << order);
folio = vma_alloc_folio(gfp, order, vma, addr, true);
if (folio) {
+ if (mem_cgroup_charge(folio, vma->vm_mm, gfp)) {
+ folio_put(folio);
+ goto next;
+ }
+ folio_throttle_swaprate(folio, gfp);
clear_huge_page(&folio->page, vmf->address, 1 << order);
return folio;
}
+next:
order = next_order(&orders, order);
}

fallback:
#endif
- return vma_alloc_zeroed_movable_folio(vmf->vma, vmf->address);
+ return folio_prealloc(vma->vm_mm, vma, vmf->address, true);
}

/*
@@ -4281,10 +4287,6 @@ static vm_fault_t do_anonymous_page(struct vm_fault *vmf)
nr_pages = folio_nr_pages(folio);
addr = ALIGN_DOWN(vmf->address, nr_pages * PAGE_SIZE);

- if (mem_cgroup_charge(folio, vma->vm_mm, GFP_KERNEL))
- goto oom_free_page;
- folio_throttle_swaprate(folio, GFP_KERNEL);
-
/*
* The memory barrier inside __folio_mark_uptodate makes sure that
* preceding stores to the page contents become visible before
@@ -4338,8 +4340,6 @@ static vm_fault_t do_anonymous_page(struct vm_fault *vmf)
release:
folio_put(folio);
goto unlock;
-oom_free_page:
- folio_put(folio);
oom:
return VM_FAULT_OOM;
}
--
2.27.0