[RFC v2 8/9] khugepaged: improve tracepoints for mTHP orders

[Nico Pache <npache@redhat.com>]

Add the order to the tracepoints to give better insight into what order
is being operated at for khugepaged.

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 9d5c00b0285c..ea2fe20a39f5 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, 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(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=%d",
 		__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 page *page, int none_or_zero,
-		 int referenced, bool  writable, int status),
+		 int referenced, bool  writable, int status, int order),
 
-	TP_ARGS(page, none_or_zero, referenced, writable, status),
+	TP_ARGS(page, 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(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=%d",
 		__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,
+			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(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=%d",
 		__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 cd310989725b..e2ba18e57064 100644
--- a/mm/khugepaged.c
+++ b/mm/khugepaged.c
@@ -713,13 +713,14 @@ static int __collapse_huge_page_isolate(struct vm_area_struct *vma,
 	} else {
 		result = SCAN_SUCCEED;
 		trace_mm_collapse_huge_page_isolate(&folio->page, 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->page, none_or_zero,
-					    referenced, writable, result);
+					    referenced, writable, result, order);
 	return result;
 }
 
@@ -1088,7 +1089,8 @@ 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;
 }
 
@@ -1305,7 +1307,7 @@ 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;
 }
 
-- 
2.48.1