Patch "mm/khugepaged: convert alloc_charge_hpage() to use folios" has been added to the 6.6-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    mm/khugepaged: convert alloc_charge_hpage() to use folios

to the 6.6-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     mm-khugepaged-convert-alloc_charge_hpage-to-use-foli.patch
and it can be found in the queue-6.6 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 7f4c7302b5c4a2c4a695a3870390d32f8c792181
Author: Vishal Moola (Oracle) <vishal.moola@xxxxxxxxx>
Date:   Fri Oct 20 11:33:30 2023 -0700

    mm/khugepaged: convert alloc_charge_hpage() to use folios
    
    [ Upstream commit b455f39d228935f88eebcd1f7c1a6981093c6a3b ]
    
    Also remove count_memcg_page_event now that its last caller no longer uses
    it and reword hpage_collapse_alloc_page() to hpage_collapse_alloc_folio().
    
    This removes 1 call to compound_head() and helps convert khugepaged to
    use folios throughout.
    
    Link: https://lkml.kernel.org/r/20231020183331.10770-5-vishal.moola@xxxxxxxxx
    Signed-off-by: Vishal Moola (Oracle) <vishal.moola@xxxxxxxxx>
    Reviewed-by: Rik van Riel <riel@xxxxxxxxxxx>
    Reviewed-by: Yang Shi <shy828301@xxxxxxxxx>
    Cc: Kefeng Wang <wangkefeng.wang@xxxxxxxxxx>
    Cc: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
    Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
    Stable-dep-of: 37f0b47c5143 ("mm: khugepaged: fix the arguments order in khugepaged_collapse_file trace point")
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index e4e24da16d2c3..b1fdb1554f2f9 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -1080,15 +1080,6 @@ static inline void count_memcg_events(struct mem_cgroup *memcg,
 	local_irq_restore(flags);
 }
 
-static inline void count_memcg_page_event(struct page *page,
-					  enum vm_event_item idx)
-{
-	struct mem_cgroup *memcg = page_memcg(page);
-
-	if (memcg)
-		count_memcg_events(memcg, idx, 1);
-}
-
 static inline void count_memcg_folio_events(struct folio *folio,
 		enum vm_event_item idx, unsigned long nr)
 {
@@ -1565,11 +1556,6 @@ static inline void __count_memcg_events(struct mem_cgroup *memcg,
 {
 }
 
-static inline void count_memcg_page_event(struct page *page,
-					  int idx)
-{
-}
-
 static inline void count_memcg_folio_events(struct folio *folio,
 		enum vm_event_item idx, unsigned long nr)
 {
diff --git a/mm/khugepaged.c b/mm/khugepaged.c
index 88433cc25d8a5..97cc4ef061832 100644
--- a/mm/khugepaged.c
+++ b/mm/khugepaged.c
@@ -887,16 +887,16 @@ static int hpage_collapse_find_target_node(struct collapse_control *cc)
 }
 #endif
 
-static bool hpage_collapse_alloc_page(struct page **hpage, gfp_t gfp, int node,
+static bool hpage_collapse_alloc_folio(struct folio **folio, gfp_t gfp, int node,
 				      nodemask_t *nmask)
 {
-	*hpage = __alloc_pages(gfp, HPAGE_PMD_ORDER, node, nmask);
-	if (unlikely(!*hpage)) {
+	*folio = __folio_alloc(gfp, HPAGE_PMD_ORDER, node, nmask);
+
+	if (unlikely(!*folio)) {
 		count_vm_event(THP_COLLAPSE_ALLOC_FAILED);
 		return false;
 	}
 
-	folio_prep_large_rmappable((struct folio *)*hpage);
 	count_vm_event(THP_COLLAPSE_ALLOC);
 	return true;
 }
@@ -1063,17 +1063,20 @@ static int alloc_charge_hpage(struct page **hpage, struct mm_struct *mm,
 	int node = hpage_collapse_find_target_node(cc);
 	struct folio *folio;
 
-	if (!hpage_collapse_alloc_page(hpage, gfp, node, &cc->alloc_nmask))
+	if (!hpage_collapse_alloc_folio(&folio, gfp, node, &cc->alloc_nmask)) {
+		*hpage = NULL;
 		return SCAN_ALLOC_HUGE_PAGE_FAIL;
+	}
 
-	folio = page_folio(*hpage);
 	if (unlikely(mem_cgroup_charge(folio, mm, gfp))) {
 		folio_put(folio);
 		*hpage = NULL;
 		return SCAN_CGROUP_CHARGE_FAIL;
 	}
-	count_memcg_page_event(*hpage, THP_COLLAPSE_ALLOC);
 
+	count_memcg_folio_events(folio, THP_COLLAPSE_ALLOC, 1);
+
+	*hpage = folio_page(folio, 0);
 	return SCAN_SUCCEED;
 }