+ hugetlb-perform-vmemmap-optimization-on-a-list-of-pages.patch added to mm-unstable branch

[Andrew Morton <akpm@linux-foundation.org>]

The patch titled
     Subject: hugetlb: perform vmemmap optimization on a list of pages
has been added to the -mm mm-unstable branch.  Its filename is
     hugetlb-perform-vmemmap-optimization-on-a-list-of-pages.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/hugetlb-perform-vmemmap-optimization-on-a-list-of-pages.patch

This patch will later appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Mike Kravetz <mike.kravetz@oracle.com>
Subject: hugetlb: perform vmemmap optimization on a list of pages
Date: Fri, 15 Sep 2023 15:15:40 -0700

When adding hugetlb pages to the pool, we first create a list of the
allocated pages before adding to the pool.  Pass this list of pages to a
new routine hugetlb_vmemmap_optimize_folios() for vmemmap optimization.

We also modify the routine vmemmap_should_optimize() to check for pages
that are already optimized.  There are code paths that might request
vmemmap optimization twice and we want to make sure this is not attempted.

Link: https://lkml.kernel.org/r/20230915221548.552084-8-mike.kravetz@oracle.com
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: James Houghton <jthoughton@google.com>
Cc: Joao Martins <joao.m.martins@oracle.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Naoya Horiguchi <naoya.horiguchi@linux.dev>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Cc: Xiongchun Duan <duanxiongchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/hugetlb.c         |    5 +++++
 mm/hugetlb_vmemmap.c |   11 +++++++++++
 mm/hugetlb_vmemmap.h |    5 +++++
 3 files changed, 21 insertions(+)

--- a/mm/hugetlb.c~hugetlb-perform-vmemmap-optimization-on-a-list-of-pages
+++ a/mm/hugetlb.c
@@ -2249,6 +2249,11 @@ static void prep_and_add_allocated_folio
 	struct folio *folio, *tmp_f;
 
 	/*
+	 * Send list for bulk vmemmap optimization processing
+	 */
+	hugetlb_vmemmap_optimize_folios(h, folio_list);
+
+	/*
 	 * Add all new pool pages to free lists in one lock cycle
 	 */
 	spin_lock_irq(&hugetlb_lock);
--- a/mm/hugetlb_vmemmap.c~hugetlb-perform-vmemmap-optimization-on-a-list-of-pages
+++ a/mm/hugetlb_vmemmap.c
@@ -483,6 +483,9 @@ int hugetlb_vmemmap_restore(const struct
 /* Return true iff a HugeTLB whose vmemmap should and can be optimized. */
 static bool vmemmap_should_optimize(const struct hstate *h, const struct page *head)
 {
+	if (HPageVmemmapOptimized((struct page *)head))
+		return false;
+
 	if (!READ_ONCE(vmemmap_optimize_enabled))
 		return false;
 
@@ -572,6 +575,14 @@ void hugetlb_vmemmap_optimize(const stru
 		SetHPageVmemmapOptimized(head);
 }
 
+void hugetlb_vmemmap_optimize_folios(struct hstate *h, struct list_head *folio_list)
+{
+	struct folio *folio;
+
+	list_for_each_entry(folio, folio_list, lru)
+		hugetlb_vmemmap_optimize(h, &folio->page);
+}
+
 static struct ctl_table hugetlb_vmemmap_sysctls[] = {
 	{
 		.procname	= "hugetlb_optimize_vmemmap",
--- a/mm/hugetlb_vmemmap.h~hugetlb-perform-vmemmap-optimization-on-a-list-of-pages
+++ a/mm/hugetlb_vmemmap.h
@@ -20,6 +20,7 @@
 #ifdef CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP
 int hugetlb_vmemmap_restore(const struct hstate *h, struct page *head);
 void hugetlb_vmemmap_optimize(const struct hstate *h, struct page *head);
+void hugetlb_vmemmap_optimize_folios(struct hstate *h, struct list_head *folio_list);
 
 static inline unsigned int hugetlb_vmemmap_size(const struct hstate *h)
 {
@@ -48,6 +49,10 @@ static inline void hugetlb_vmemmap_optim
 {
 }
 
+static inline void hugetlb_vmemmap_optimize_folios(struct hstate *h, struct list_head *folio_list)
+{
+}
+
 static inline unsigned int hugetlb_vmemmap_optimizable_size(const struct hstate *h)
 {
 	return 0;
_

Patches currently in -mm which might be from mike.kravetz@oracle.com are

hugetlb-set-hugetlb-page-flag-before-optimizing-vmemmap.patch
hugetlb-optimize-update_and_free_pages_bulk-to-avoid-lock-cycles.patch
hugetlb-restructure-pool-allocations.patch
hugetlb-perform-vmemmap-optimization-on-a-list-of-pages.patch
hugetlb-perform-vmemmap-restoration-on-a-list-of-pages.patch
hugetlb-batch-freeing-of-vmemmap-pages.patch
hugetlb-batch-tlb-flushes-when-restoring-vmemmap.patch