The quilt patch titled Subject: mm: shmem: rename mTHP shmem counters has been removed from the -mm tree. Its filename was mm-shmem-rename-mthp-shmem-counters.patch

This patch was dropped because it was merged into the mm-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

------------------------------------------------------ From: Ryan Roberts ryan.roberts@arm.com Subject: mm: shmem: rename mTHP shmem counters Date: Wed, 10 Jul 2024 10:55:01 +0100

The legacy PMD-sized THP counters at /proc/vmstat include thp_file_alloc, thp_file_fallback and thp_file_fallback_charge, which rather confusingly refer to shmem THP and do not include any other types of file pages. This is inconsistent since in most other places in the kernel, THP counters are explicitly separated for anon, shmem and file flavours. However, we are stuck with it since it constitutes a user ABI.

Recently, commit 66f44583f9b6 ("mm: shmem: add mTHP counters for anonymous shmem") added equivalent mTHP stats for shmem, keeping the same "file_" prefix in the names. But in future, we may want to add extra stats to cover actual file pages, at which point, it would all become very confusing.

So let's take the opportunity to rename these new counters "shmem_" before the change makes it upstream and the ABI becomes immutable. While we are at it, let's improve the documentation for the legacy counters to make it clear that they count shmem pages only.

Link: https://lkml.kernel.org/r/20240710095503.3193901-1-ryan.roberts@arm.com Signed-off-by: Ryan Roberts ryan.roberts@arm.com Reviewed-by: Baolin Wang baolin.wang@linux.alibaba.com Reviewed-by: Lance Yang ioworker0@gmail.com Reviewed-by: Zi Yan ziy@nvidia.com Reviewed-by: Barry Song baohua@kernel.org Acked-by: David Hildenbrand david@redhat.com Cc: Daniel Gomez da.gomez@samsung.com Cc: Hugh Dickins hughd@google.com Cc: Jonathan Corbet corbet@lwn.net Cc: Matthew Wilcox (Oracle) willy@infradead.org Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org ---

Documentation/admin-guide/mm/transhuge.rst | 29 ++++++++++--------- include/linux/huge_mm.h | 6 +-- mm/huge_memory.c | 12 +++---- mm/shmem.c | 8 ++--- 4 files changed, 29 insertions(+), 26 deletions(-)

--- a/Documentation/admin-guide/mm/transhuge.rst~mm-shmem-rename-mthp-shmem-counters +++ a/Documentation/admin-guide/mm/transhuge.rst @@ -412,20 +412,23 @@ thp_collapse_alloc_failed the allocation.

thp_file_alloc - is incremented every time a file huge page is successfully - allocated. + is incremented every time a shmem huge page is successfully + allocated (Note that despite being named after "file", the counter + measures only shmem).

thp_file_fallback - is incremented if a file huge page is attempted to be allocated - but fails and instead falls back to using small pages. + is incremented if a shmem huge page is attempted to be allocated + but fails and instead falls back to using small pages. (Note that + despite being named after "file", the counter measures only shmem).

thp_file_fallback_charge - is incremented if a file huge page cannot be charged and instead + is incremented if a shmem huge page cannot be charged and instead falls back to using small pages even though the allocation was - successful. + successful. (Note that despite being named after "file", the + counter measures only shmem).

thp_file_mapped - is incremented every time a file huge page is mapped into + is incremented every time a file or shmem huge page is mapped into user address space.

thp_split_page @@ -496,16 +499,16 @@ swpout_fallback Usually because failed to allocate some continuous swap space for the huge page.

-file_alloc - is incremented every time a file huge page is successfully +shmem_alloc + is incremented every time a shmem huge page is successfully allocated.

-file_fallback - is incremented if a file huge page is attempted to be allocated +shmem_fallback + is incremented if a shmem huge page is attempted to be allocated but fails and instead falls back to using small pages.

-file_fallback_charge - is incremented if a file huge page cannot be charged and instead +shmem_fallback_charge + is incremented if a shmem huge page cannot be charged and instead falls back to using small pages even though the allocation was successful.

--- a/include/linux/huge_mm.h~mm-shmem-rename-mthp-shmem-counters +++ a/include/linux/huge_mm.h @@ -269,9 +269,9 @@ enum mthp_stat_item { MTHP_STAT_ANON_FAULT_FALLBACK_CHARGE, MTHP_STAT_SWPOUT, MTHP_STAT_SWPOUT_FALLBACK, - MTHP_STAT_FILE_ALLOC, - MTHP_STAT_FILE_FALLBACK, - MTHP_STAT_FILE_FALLBACK_CHARGE, + MTHP_STAT_SHMEM_ALLOC, + MTHP_STAT_SHMEM_FALLBACK, + MTHP_STAT_SHMEM_FALLBACK_CHARGE, MTHP_STAT_SPLIT, MTHP_STAT_SPLIT_FAILED, MTHP_STAT_SPLIT_DEFERRED, --- a/mm/huge_memory.c~mm-shmem-rename-mthp-shmem-counters +++ a/mm/huge_memory.c @@ -568,9 +568,9 @@ DEFINE_MTHP_STAT_ATTR(anon_fault_fallbac DEFINE_MTHP_STAT_ATTR(anon_fault_fallback_charge, MTHP_STAT_ANON_FAULT_FALLBACK_CHARGE); DEFINE_MTHP_STAT_ATTR(swpout, MTHP_STAT_SWPOUT); DEFINE_MTHP_STAT_ATTR(swpout_fallback, MTHP_STAT_SWPOUT_FALLBACK); -DEFINE_MTHP_STAT_ATTR(file_alloc, MTHP_STAT_FILE_ALLOC); -DEFINE_MTHP_STAT_ATTR(file_fallback, MTHP_STAT_FILE_FALLBACK); -DEFINE_MTHP_STAT_ATTR(file_fallback_charge, MTHP_STAT_FILE_FALLBACK_CHARGE); +DEFINE_MTHP_STAT_ATTR(shmem_alloc, MTHP_STAT_SHMEM_ALLOC); +DEFINE_MTHP_STAT_ATTR(shmem_fallback, MTHP_STAT_SHMEM_FALLBACK); +DEFINE_MTHP_STAT_ATTR(shmem_fallback_charge, MTHP_STAT_SHMEM_FALLBACK_CHARGE); DEFINE_MTHP_STAT_ATTR(split, MTHP_STAT_SPLIT); DEFINE_MTHP_STAT_ATTR(split_failed, MTHP_STAT_SPLIT_FAILED); DEFINE_MTHP_STAT_ATTR(split_deferred, MTHP_STAT_SPLIT_DEFERRED); @@ -581,9 +581,9 @@ static struct attribute *stats_attrs[] = &anon_fault_fallback_charge_attr.attr, &swpout_attr.attr, &swpout_fallback_attr.attr, - &file_alloc_attr.attr, - &file_fallback_attr.attr, - &file_fallback_charge_attr.attr, + &shmem_alloc_attr.attr, + &shmem_fallback_attr.attr, + &shmem_fallback_charge_attr.attr, &split_attr.attr, &split_failed_attr.attr, &split_deferred_attr.attr, --- a/mm/shmem.c~mm-shmem-rename-mthp-shmem-counters +++ a/mm/shmem.c @@ -1777,7 +1777,7 @@ static struct folio *shmem_alloc_and_add if (pages == HPAGE_PMD_NR) count_vm_event(THP_FILE_FALLBACK); #ifdef CONFIG_TRANSPARENT_HUGEPAGE - count_mthp_stat(order, MTHP_STAT_FILE_FALLBACK); + count_mthp_stat(order, MTHP_STAT_SHMEM_FALLBACK); #endif order = next_order(&suitable_orders, order); } @@ -1804,8 +1804,8 @@ allocated: count_vm_event(THP_FILE_FALLBACK_CHARGE); } #ifdef CONFIG_TRANSPARENT_HUGEPAGE - count_mthp_stat(folio_order(folio), MTHP_STAT_FILE_FALLBACK); - count_mthp_stat(folio_order(folio), MTHP_STAT_FILE_FALLBACK_CHARGE); + count_mthp_stat(folio_order(folio), MTHP_STAT_SHMEM_FALLBACK); + count_mthp_stat(folio_order(folio), MTHP_STAT_SHMEM_FALLBACK_CHARGE); #endif } goto unlock; @@ -2181,7 +2181,7 @@ repeat: if (folio_test_pmd_mappable(folio)) count_vm_event(THP_FILE_ALLOC); #ifdef CONFIG_TRANSPARENT_HUGEPAGE - count_mthp_stat(folio_order(folio), MTHP_STAT_FILE_ALLOC); + count_mthp_stat(folio_order(folio), MTHP_STAT_SHMEM_ALLOC); #endif goto alloced; } _

Patches currently in -mm which might be from ryan.roberts@arm.com are