* [to-be-updated] mm-khugepaged-avoid-unnecessary-mthp-collapse-attempts.patch removed from -mm tree
@ 2026-05-03 13:21 Andrew Morton
0 siblings, 0 replies; 2+ messages in thread
From: Andrew Morton @ 2026-05-03 13:21 UTC (permalink / raw)
To: mm-commits, zokeefe, ziy, ying.huang, yang, willy, will,
wangkefeng.wang, vishal.moola, vbabka, usama.arif, tiwai,
thomas.hellstrom, surenb, sunnanyong, shivankg, ryan.roberts,
rppt, rostedt, rientjes, richard.weiyang, rdunlap, raquini,
rakie.kim, pfalcato, peterx, mhocko, mhiramat, matthew.brost,
mathieu.desnoyers, ljs, liam, lance.yang, joshua.hahnjy, jannh,
jack, jackmanb, hughd, hannes, gourry, dev.jain, david, corbet,
catalin.marinas, byungchul, baolin.wang, baohua, bagasdotme,
apopple, anshuman.khandual, aarcange, npache, akpm
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The quilt patch titled
Subject: mm/khugepaged: avoid unnecessary mTHP collapse attempts
has been removed from the -mm tree. Its filename was
mm-khugepaged-avoid-unnecessary-mthp-collapse-attempts.patch
This patch was dropped because an updated version will be issued
------------------------------------------------------
From: Nico Pache <npache@redhat.com>
Subject: mm/khugepaged: avoid unnecessary mTHP collapse attempts
Date: Sun, 19 Apr 2026 12:57:48 -0600
There are cases where, if an attempted collapse fails, all subsequent
orders are guaranteed to also fail. Avoid these collapse attempts by
bailing out early.
Link: https://lore.kernel.org/20260419185750.260784-12-npache@redhat.com
Signed-off-by: Nico Pache <npache@redhat.com>
Reviewed-by: Lorenzo Stoakes <ljs@kernel.org>
Acked-by: Usama Arif <usama.arif@linux.dev>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Bagas Sanjaya <bagasdotme@gmail.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Brendan Jackman <jackmanb@google.com>
Cc: Byungchul Park <byungchul@sk.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Gregory Price <gourry@gourry.net>
Cc: "Huang, Ying" <ying.huang@linux.alibaba.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jann Horn <jannh@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Joshua Hahn <joshua.hahnjy@gmail.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Lance Yang <lance.yang@linux.dev>
Cc: Liam Howlett <liam@infradead.org>
Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Nanyong Sun <sunnanyong@huawei.com>
Cc: Pedro Falcato <pfalcato@suse.de>
Cc: Peter Xu <peterx@redhat.com>
Cc: Rafael Aquini <raquini@redhat.com>
Cc: Rakie Kim <rakie.kim@sk.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Shivank Garg <shivankg@amd.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Takashi Iwai (SUSE) <tiwai@suse.de>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yang Shi <yang@os.amperecomputing.com>
Cc: Zach O'Keefe <zokeefe@google.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
mm/khugepaged.c | 24 +++++++++++++++++++++++-
1 file changed, 23 insertions(+), 1 deletion(-)
--- a/mm/khugepaged.c~mm-khugepaged-avoid-unnecessary-mthp-collapse-attempts
+++ a/mm/khugepaged.c
@@ -1517,9 +1517,31 @@ static int mthp_collapse(struct mm_struc
collapse_address = address + offset * PAGE_SIZE;
ret = collapse_huge_page(mm, collapse_address, referenced,
unmapped, cc, order);
- if (ret == SCAN_SUCCEED) {
+
+ switch (ret) {
+ /* Cases where we continue to next collapse candidate */
+ case SCAN_SUCCEED:
collapsed += nr_ptes;
+ fallthrough;
+ case SCAN_PTE_MAPPED_HUGEPAGE:
continue;
+ /* Cases where lower orders might still succeed */
+ case SCAN_LACK_REFERENCED_PAGE:
+ case SCAN_EXCEED_NONE_PTE:
+ case SCAN_EXCEED_SWAP_PTE:
+ case SCAN_EXCEED_SHARED_PTE:
+ case SCAN_PAGE_LOCK:
+ case SCAN_PAGE_COUNT:
+ case SCAN_PAGE_LRU:
+ case SCAN_PAGE_NULL:
+ case SCAN_DEL_PAGE_LRU:
+ case SCAN_PTE_NON_PRESENT:
+ case SCAN_PTE_UFFD_WP:
+ case SCAN_ALLOC_HUGE_PAGE_FAIL:
+ goto next_order;
+ /* Cases where no further collapse is possible */
+ default:
+ return collapsed;
}
}
_
Patches currently in -mm which might be from npache@redhat.com are
documentation-mm-update-the-admin-guide-for-mthp-collapse.patch
^ permalink raw reply [flat|nested] 2+ messages in thread
* [to-be-updated] mm-khugepaged-avoid-unnecessary-mthp-collapse-attempts.patch removed from -mm tree
@ 2026-05-11 20:56 Andrew Morton
0 siblings, 0 replies; 2+ messages in thread
From: Andrew Morton @ 2026-05-11 20:56 UTC (permalink / raw)
To: mm-commits, npache, akpm
[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
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The quilt patch titled
Subject: mm/khugepaged: avoid unnecessary mTHP collapse attempts
has been removed from the -mm tree. Its filename was
mm-khugepaged-avoid-unnecessary-mthp-collapse-attempts.patch
This patch was dropped because an updated version will be issued
------------------------------------------------------
From: Nico Pache <npache@redhat.com>
Subject: mm/khugepaged: avoid unnecessary mTHP collapse attempts
Date: Sun, 19 Apr 2026 12:57:48 -0600
There are cases where, if an attempted collapse fails, all subsequent
orders are guaranteed to also fail. Avoid these collapse attempts by
bailing out early.
Link: https://lore.kernel.org/20260419185750.260784-12-npache@redhat.com
Signed-off-by: Nico Pache <npache@redhat.com>
Reviewed-by: Lorenzo Stoakes <ljs@kernel.org>
Acked-by: Usama Arif <usama.arif@linux.dev>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Bagas Sanjaya <bagasdotme@gmail.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Brendan Jackman <jackmanb@google.com>
Cc: Byungchul Park <byungchul@sk.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Gregory Price <gourry@gourry.net>
Cc: "Huang, Ying" <ying.huang@linux.alibaba.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jann Horn <jannh@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Joshua Hahn <joshua.hahnjy@gmail.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Lance Yang <lance.yang@linux.dev>
Cc: Liam Howlett <liam@infradead.org>
Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Nanyong Sun <sunnanyong@huawei.com>
Cc: Pedro Falcato <pfalcato@suse.de>
Cc: Peter Xu <peterx@redhat.com>
Cc: Rafael Aquini <raquini@redhat.com>
Cc: Rakie Kim <rakie.kim@sk.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Shivank Garg <shivankg@amd.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Takashi Iwai (SUSE) <tiwai@suse.de>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yang Shi <yang@os.amperecomputing.com>
Cc: Zach O'Keefe <zokeefe@google.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
mm/khugepaged.c | 24 +++++++++++++++++++++++-
1 file changed, 23 insertions(+), 1 deletion(-)
--- a/mm/khugepaged.c~mm-khugepaged-avoid-unnecessary-mthp-collapse-attempts
+++ a/mm/khugepaged.c
@@ -1517,9 +1517,31 @@ static int mthp_collapse(struct mm_struc
collapse_address = address + offset * PAGE_SIZE;
ret = collapse_huge_page(mm, collapse_address, referenced,
unmapped, cc, order);
- if (ret == SCAN_SUCCEED) {
+
+ switch (ret) {
+ /* Cases where we continue to next collapse candidate */
+ case SCAN_SUCCEED:
collapsed += nr_ptes;
+ fallthrough;
+ case SCAN_PTE_MAPPED_HUGEPAGE:
continue;
+ /* Cases where lower orders might still succeed */
+ case SCAN_LACK_REFERENCED_PAGE:
+ case SCAN_EXCEED_NONE_PTE:
+ case SCAN_EXCEED_SWAP_PTE:
+ case SCAN_EXCEED_SHARED_PTE:
+ case SCAN_PAGE_LOCK:
+ case SCAN_PAGE_COUNT:
+ case SCAN_PAGE_LRU:
+ case SCAN_PAGE_NULL:
+ case SCAN_DEL_PAGE_LRU:
+ case SCAN_PTE_NON_PRESENT:
+ case SCAN_PTE_UFFD_WP:
+ case SCAN_ALLOC_HUGE_PAGE_FAIL:
+ goto next_order;
+ /* Cases where no further collapse is possible */
+ default:
+ return collapsed;
}
}
_
Patches currently in -mm which might be from npache@redhat.com are
documentation-mm-update-the-admin-guide-for-mthp-collapse.patch
^ permalink raw reply [flat|nested] 2+ messages in thread
end of thread, other threads:[~2026-05-11 20:56 UTC | newest]
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2026-05-03 13:21 [to-be-updated] mm-khugepaged-avoid-unnecessary-mthp-collapse-attempts.patch removed from -mm tree Andrew Morton
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