[PATCH v10 11/13] khugepaged: improve tracepoints for mTHP orders
From: Nico Pache <npache@redhat.com>
Date: 2025-08-19 13:46:32
Also in:
linux-doc, linux-mm, lkml
Subsystem:
memory management, memory management - thp (transparent huge page), the rest, tracing · Maintainers:
Andrew Morton, David Hildenbrand, Lorenzo Stoakes, Linus Torvalds, Steven Rostedt, Masami Hiramatsu
Add the order to the tracepoints to give better insight into what order is being operated at for khugepaged. Acked-by: David Hildenbrand <redacted> Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com> Signed-off-by: Nico Pache <npache@redhat.com> --- include/trace/events/huge_memory.h | 34 +++++++++++++++++++----------- mm/khugepaged.c | 10 +++++---- 2 files changed, 28 insertions(+), 16 deletions(-)
diff --git a/include/trace/events/huge_memory.h b/include/trace/events/huge_memory.h
index 2305df6cb485..56aa8c3b011b 100644
--- a/include/trace/events/huge_memory.h
+++ b/include/trace/events/huge_memory.h@@ -92,34 +92,37 @@ TRACE_EVENT(mm_khugepaged_scan_pmd, TRACE_EVENT(mm_collapse_huge_page, - TP_PROTO(struct mm_struct *mm, int isolated, int status), + TP_PROTO(struct mm_struct *mm, int isolated, int status, unsigned int order), - TP_ARGS(mm, isolated, status), + TP_ARGS(mm, isolated, status, order), TP_STRUCT__entry( __field(struct mm_struct *, mm) __field(int, isolated) __field(int, status) + __field(unsigned int, order) ), TP_fast_assign( __entry->mm = mm; __entry->isolated = isolated; __entry->status = status; + __entry->order = order; ), - TP_printk("mm=%p, isolated=%d, status=%s", + TP_printk("mm=%p, isolated=%d, status=%s order=%u", __entry->mm, __entry->isolated, - __print_symbolic(__entry->status, SCAN_STATUS)) + __print_symbolic(__entry->status, SCAN_STATUS), + __entry->order) ); TRACE_EVENT(mm_collapse_huge_page_isolate, TP_PROTO(struct folio *folio, int none_or_zero, - int referenced, bool writable, int status), + int referenced, bool writable, int status, unsigned int order), - TP_ARGS(folio, none_or_zero, referenced, writable, status), + TP_ARGS(folio, none_or_zero, referenced, writable, status, order), TP_STRUCT__entry( __field(unsigned long, pfn)
@@ -127,6 +130,7 @@ TRACE_EVENT(mm_collapse_huge_page_isolate, __field(int, referenced) __field(bool, writable) __field(int, status) + __field(unsigned int, order) ), TP_fast_assign(
@@ -135,27 +139,31 @@ TRACE_EVENT(mm_collapse_huge_page_isolate, __entry->referenced = referenced; __entry->writable = writable; __entry->status = status; + __entry->order = order; ), - TP_printk("scan_pfn=0x%lx, none_or_zero=%d, referenced=%d, writable=%d, status=%s", + TP_printk("scan_pfn=0x%lx, none_or_zero=%d, referenced=%d, writable=%d, status=%s order=%u", __entry->pfn, __entry->none_or_zero, __entry->referenced, __entry->writable, - __print_symbolic(__entry->status, SCAN_STATUS)) + __print_symbolic(__entry->status, SCAN_STATUS), + __entry->order) ); TRACE_EVENT(mm_collapse_huge_page_swapin, - TP_PROTO(struct mm_struct *mm, int swapped_in, int referenced, int ret), + TP_PROTO(struct mm_struct *mm, int swapped_in, int referenced, int ret, + unsigned int order), - TP_ARGS(mm, swapped_in, referenced, ret), + TP_ARGS(mm, swapped_in, referenced, ret, order), TP_STRUCT__entry( __field(struct mm_struct *, mm) __field(int, swapped_in) __field(int, referenced) __field(int, ret) + __field(unsigned int, order) ), TP_fast_assign(
@@ -163,13 +171,15 @@ TRACE_EVENT(mm_collapse_huge_page_swapin, __entry->swapped_in = swapped_in; __entry->referenced = referenced; __entry->ret = ret; + __entry->order = order; ), - TP_printk("mm=%p, swapped_in=%d, referenced=%d, ret=%d", + TP_printk("mm=%p, swapped_in=%d, referenced=%d, ret=%d, order=%u", __entry->mm, __entry->swapped_in, __entry->referenced, - __entry->ret) + __entry->ret, + __entry->order) ); TRACE_EVENT(mm_khugepaged_scan_file,
diff --git a/mm/khugepaged.c b/mm/khugepaged.c
index 81d2ffd56ab9..c13bc583a368 100644
--- a/mm/khugepaged.c
+++ b/mm/khugepaged.c@@ -721,13 +721,14 @@ static int __collapse_huge_page_isolate(struct vm_area_struct *vma, } else { result = SCAN_SUCCEED; trace_mm_collapse_huge_page_isolate(folio, none_or_zero, - referenced, writable, result); + referenced, writable, result, + order); return result; } out: release_pte_pages(pte, _pte, compound_pagelist); trace_mm_collapse_huge_page_isolate(folio, none_or_zero, - referenced, writable, result); + referenced, writable, result, order); return result; }
@@ -1123,7 +1124,8 @@ static int __collapse_huge_page_swapin(struct mm_struct *mm, result = SCAN_SUCCEED; out: - trace_mm_collapse_huge_page_swapin(mm, swapped_in, referenced, result); + trace_mm_collapse_huge_page_swapin(mm, swapped_in, referenced, result, + order); return result; }
@@ -1348,7 +1350,7 @@ static int collapse_huge_page(struct mm_struct *mm, unsigned long address, *mmap_locked = false; if (folio) folio_put(folio); - trace_mm_collapse_huge_page(mm, result == SCAN_SUCCEED, result); + trace_mm_collapse_huge_page(mm, result == SCAN_SUCCEED, result, order); return result; }
--
2.50.1