The patch titled Subject: mm/vmstat: add events for PMD based THP migration without split has been removed from the -mm tree. Its filename was mm-vmstat-add-events-for-pmd-based-thp-migration-without-split.patch This patch was dropped because an updated version will be merged ------------------------------------------------------ From: Anshuman Khandual <anshuman.khandual@xxxxxxx> Subject: mm/vmstat: add events for PMD based THP migration without split This adds the following two new VM events which will help in validating PMD based THP migration without split. Statistics reported through these events will help in performance debugging. 1. THP_PMD_MIGRATION_SUCCESS 2. THP_PMD_MIGRATION_FAILURE [hughd@xxxxxxxxxx: fix page migration crash in unmap_and_move()] Link: http://lkml.kernel.org/r/alpine.LSU.2.11.2005210643340.482@eggly.anvils [anshuman.khandual@xxxxxxx: rename thp_migration_success() to thp_pmd_migration_success() per John] Link: http://lkml.kernel.org/r/1590118444-21601-1-git-send-email-anshuman.khandual@xxxxxxx Link: http://lkml.kernel.org/r/1589784156-28831-1-git-send-email-anshuman.khandual@xxxxxxx Signed-off-by: Anshuman Khandual <anshuman.khandual@xxxxxxx> Signed-off-by: Hugh Dickins <hughd@xxxxxxxxxx> Cc: Naoya Horiguchi <n-horiguchi@xxxxxxxxxxxxx> Cc: Zi Yan <ziy@xxxxxxxxxx> Cc: John Hubbard <jhubbard@xxxxxxxxxx> Cc: Johannes Weiner <hannes@xxxxxxxxxxx> Cc: Qian Cai <cai@xxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxx> Cc: Yang Shi <yang.shi@xxxxxxxxxxxxxxxxx> Cc: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx> Cc: Daniel Jordan <daniel.m.jordan@xxxxxxxxxx> Cc: Andrea Arcangeli <aarcange@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- include/linux/vm_event_item.h | 4 ++++ mm/migrate.c | 23 +++++++++++++++++++++++ mm/vmstat.c | 4 ++++ 3 files changed, 31 insertions(+) --- a/include/linux/vm_event_item.h~mm-vmstat-add-events-for-pmd-based-thp-migration-without-split +++ a/include/linux/vm_event_item.h @@ -95,6 +95,10 @@ enum vm_event_item { PGPGIN, PGPGOUT, PS THP_ZERO_PAGE_ALLOC_FAILED, THP_SWPOUT, THP_SWPOUT_FALLBACK, +#ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION + THP_PMD_MIGRATION_SUCCESS, + THP_PMD_MIGRATION_FAILURE, +#endif #endif #ifdef CONFIG_MEMORY_BALLOON BALLOON_INFLATE, --- a/mm/migrate.c~mm-vmstat-add-events-for-pmd-based-thp-migration-without-split +++ a/mm/migrate.c @@ -1171,6 +1171,20 @@ out: #define ICE_noinline #endif +#ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION +static inline void thp_pmd_migration_success(bool success) +{ + if (success) + count_vm_event(THP_PMD_MIGRATION_SUCCESS); + else + count_vm_event(THP_PMD_MIGRATION_FAILURE); +} +#else +static inline void thp_pmd_migration_success(bool success) +{ +} +#endif + /* * Obtain the lock on page, remove all ptes and migrate the page * to the newly allocated page in newpage. @@ -1233,6 +1247,14 @@ out: * we want to retry. */ if (rc == MIGRATEPAGE_SUCCESS) { + /* + * When the page to be migrated has been freed from under + * us, that is considered a MIGRATEPAGE_SUCCESS, but no + * newpage has been allocated. It should not be counted + * as a successful THP migration. + */ + if (newpage && PageTransHuge(newpage)) + thp_pmd_migration_success(true); put_page(page); if (reason == MR_MEMORY_FAILURE) { /* @@ -1475,6 +1497,7 @@ retry: unlock_page(page); if (!rc) { list_safe_reset_next(page, page2, lru); + thp_pmd_migration_success(false); goto retry; } } --- a/mm/vmstat.c~mm-vmstat-add-events-for-pmd-based-thp-migration-without-split +++ a/mm/vmstat.c @@ -1320,6 +1320,10 @@ const char * const vmstat_text[] = { "thp_zero_page_alloc_failed", "thp_swpout", "thp_swpout_fallback", +#ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION + "thp_pmd_migration_success", + "thp_pmd_migration_failure", +#endif #endif #ifdef CONFIG_MEMORY_BALLOON "balloon_inflate", _ Patches currently in -mm which might be from anshuman.khandual@xxxxxxx are mm-debug_vm_pgtable-add-tests-validating-arch-helpers-for-core-mm-features.patch mm-debug_vm_pgtable-add-tests-validating-advanced-arch-page-table-helpers.patch mm-debug_vm_pgtable-add-debug-prints-for-individual-tests.patch documentation-mm-add-descriptions-for-arch-page-table-helpers.patch