Add huge_memory:trace_mm_khugepaged_scan_file tracepoint to
hpage_collapse_scan_file() analogously to hpage_collapse_scan_pmd().
While this change is targeted at debugging MADV_COLLAPSE pathway, the
"mm_khugepaged" prefix is retained for symmetry with
huge_memory:trace_mm_khugepaged_scan_pmd, which retains it's legacy name
to prevent changing kernel ABI as much as possible.
Signed-off-by: Zach O'Keefe <zokeefe@xxxxxxxxxx>
---
include/trace/events/huge_memory.h | 34 ++++++++++++++++++++++++++++++
mm/khugepaged.c | 3 ++-
2 files changed, 36 insertions(+), 1 deletion(-)
diff --git a/include/trace/events/huge_memory.h b/include/trace/events/huge_memory.h
index a8db658e99e9..1d2dd88dc3c4 100644
--- a/include/trace/events/huge_memory.h
+++ b/include/trace/events/huge_memory.h
@@ -169,5 +169,39 @@ TRACE_EVENT(mm_collapse_huge_page_swapin,
__entry->ret)
);
+TRACE_EVENT(mm_khugepaged_scan_file,
+
+ TP_PROTO(struct mm_struct *mm, struct page *page, const char *filename,
+ int present, int swap, int result),
+
+ TP_ARGS(mm, page, filename, present, swap, result),
+
+ TP_STRUCT__entry(
+ __field(struct mm_struct *, mm)
+ __field(unsigned long, pfn)
+ __string(filename, filename)
+ __field(int, present)
+ __field(int, swap)
+ __field(int, result)
+ ),
+
+ TP_fast_assign(
+ __entry->mm = mm;
+ __entry->pfn = page ? page_to_pfn(page) : -1;
+ __assign_str(filename, filename);
+ __entry->present = present;
+ __entry->swap = swap;
+ __entry->result = result;
+ ),
+
+ TP_printk("mm=%p, scan_pfn=0x%lx, filename=%s, present=%d, swap=%d, result=%s",
+ __entry->mm,
+ __entry->pfn,
+ __get_str(filename),
+ __entry->present,
+ __entry->swap,
+ __print_symbolic(__entry->result, SCAN_STATUS))
+);
+
#endif /* __HUGE_MEMORY_H */
#include <trace/define_trace.h>
diff --git a/mm/khugepaged.c b/mm/khugepaged.c
index 34c0c74b3839..55144f33ba09 100644
--- a/mm/khugepaged.c
+++ b/mm/khugepaged.c
@@ -2171,7 +2171,8 @@ static int hpage_collapse_scan_file(struct mm_struct *mm, unsigned long addr,
}
}
- /* TODO: tracepoints */
+ trace_mm_khugepaged_scan_file(mm, page, file->f_path.dentry->d_iname,
+ present, swap, result);
return result;
}
#else
--
2.37.2.672.g94769d06f0-goog
