The patch titled
Subject: hugetlb_cgroup: support noreserve mappings
has been added to the -mm tree. Its filename is
hugetlb_cgroup-support-noreserve-mappings.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/hugetlb_cgroup-support-noreserve-mappings.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/hugetlb_cgroup-support-noreserve-mappings.patch
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------------------------------------------------------
From: Mina Almasry <almasrymina@xxxxxxxxxx>
Subject: hugetlb_cgroup: support noreserve mappings
Support MAP_NORESERVE accounting as part of the new counter.
For each hugepage allocation, at allocation time we check if there is a
reservation for this allocation or not. If there is a reservation for
this allocation, then this allocation was charged at reservation time, and
we don't re-account it. If there is no reserevation for this allocation,
we charge the appropriate hugetlb_cgroup.
The hugetlb_cgroup to uncharge for this allocation is stored in
page[3].private. We use new APIs added in an earlier patch to set this
pointer.
Link: http://lkml.kernel.org/r/20200211213128.73302-6-almasrymina@xxxxxxxxxx
Signed-off-by: Mina Almasry <almasrymina@xxxxxxxxxx>
Cc: David Rientjes <rientjes@xxxxxxxxxx>
Cc: Greg Thelen <gthelen@xxxxxxxxxx>
Cc: Mike Kravetz <mike.kravetz@xxxxxxxxxx>
Cc: Sandipan Das <sandipan@xxxxxxxxxxxxx>
Cc: Shakeel Butt <shakeelb@xxxxxxxxxx>
Cc: Shuah Khan <shuah@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/hugetlb.c | 27 ++++++++++++++++++++++++++-
1 file changed, 26 insertions(+), 1 deletion(-)
--- a/mm/hugetlb.c~hugetlb_cgroup-support-noreserve-mappings
+++ a/mm/hugetlb.c
@@ -1345,6 +1345,8 @@ static void __free_huge_page(struct page
clear_page_huge_active(page);
hugetlb_cgroup_uncharge_page(hstate_index(h),
pages_per_huge_page(h), page);
+ hugetlb_cgroup_uncharge_page_rsvd(hstate_index(h),
+ pages_per_huge_page(h), page);
if (restore_reserve)
h->resv_huge_pages++;
@@ -2181,6 +2183,7 @@ struct page *alloc_huge_page(struct vm_a
long gbl_chg;
int ret, idx;
struct hugetlb_cgroup *h_cg;
+ bool deferred_reserve;
idx = hstate_index(h);
/*
@@ -2218,9 +2221,19 @@ struct page *alloc_huge_page(struct vm_a
gbl_chg = 1;
}
+ /* If this allocation is not consuming a reservation, charge it now.
+ */
+ deferred_reserve = map_chg || avoid_reserve || !vma_resv_map(vma);
+ if (deferred_reserve) {
+ ret = hugetlb_cgroup_charge_cgroup_rsvd(
+ idx, pages_per_huge_page(h), &h_cg);
+ if (ret)
+ goto out_subpool_put;
+ }
+
ret = hugetlb_cgroup_charge_cgroup(idx, pages_per_huge_page(h), &h_cg);
if (ret)
- goto out_subpool_put;
+ goto out_uncharge_cgroup_reservation;
spin_lock(&hugetlb_lock);
/*
@@ -2243,6 +2256,14 @@ struct page *alloc_huge_page(struct vm_a
/* Fall through */
}
hugetlb_cgroup_commit_charge(idx, pages_per_huge_page(h), h_cg, page);
+ /* If allocation is not consuming a reservation, also store the
+ * hugetlb_cgroup pointer on the page.
+ */
+ if (deferred_reserve) {
+ hugetlb_cgroup_commit_charge_rsvd(idx, pages_per_huge_page(h),
+ h_cg, page);
+ }
+
spin_unlock(&hugetlb_lock);
set_page_private(page, (unsigned long)spool);
@@ -2267,6 +2288,10 @@ struct page *alloc_huge_page(struct vm_a
out_uncharge_cgroup:
hugetlb_cgroup_uncharge_cgroup(idx, pages_per_huge_page(h), h_cg);
+out_uncharge_cgroup_reservation:
+ if (deferred_reserve)
+ hugetlb_cgroup_uncharge_cgroup_rsvd(idx, pages_per_huge_page(h),
+ h_cg);
out_subpool_put:
if (map_chg || avoid_reserve)
hugepage_subpool_put_pages(spool, 1);
_
Patches currently in -mm which might be from almasrymina@xxxxxxxxxx are
hugetlb_cgroup-add-hugetlb_cgroup-reservation-counter.patch
hugetlb_cgroup-add-interface-for-charge-uncharge-hugetlb-reservations.patch
hugetlb_cgroup-add-reservation-accounting-for-private-mappings.patch
hugetlb-disable-region_add-file_region-coalescing.patch
hugetlb_cgroup-add-accounting-for-shared-mappings.patch
hugetlb_cgroup-support-noreserve-mappings.patch
hugetlb-support-file_region-coalescing-again.patch
hugetlb_cgroup-add-hugetlb_cgroup-reservation-tests.patch
hugetlb_cgroup-add-hugetlb_cgroup-reservation-docs.patch
