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mm: khugepaged: fix the arguments order in khugepaged_collapse_file trace point

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The "addr" and "is_shmem" arguments have different order in TP_PROTO and
TP_ARGS.  This resulted in the incorrect trace result:

text-hugepage-644429 [276] 392092.878683: mm_khugepaged_collapse_file:
mm=0xffff20025d52c440, hpage_pfn=0x200678c00, index=512, addr=1, is_shmem=0,
filename=text-hugepage, nr=512, result=failed

The value of "addr" is wrong because it was treated as bool value, the
type of is_shmem.

Fix the order in TP_PROTO to keep "addr" is before "is_shmem" since the
original patch review suggested this order to achieve best packing.

And use "lx" for "addr" instead of "ld" in TP_printk because address is
typically shown in hex.

After the fix, the trace result looks correct:

text-hugepage-7291  [004]   128.627251: mm_khugepaged_collapse_file:
mm=0xffff0001328f9500, hpage_pfn=0x20016ea00, index=512, addr=0x400000,
is_shmem=0, filename=text-hugepage, nr=512, result=failed

Link: https://lkml.kernel.org/r/20241012011702.1084846-1-yang@os.amperecomputing.com
Fixes: 4c9473e87e ("mm/khugepaged: add tracepoint to collapse_file()")
Signed-off-by: Yang Shi <yang@os.amperecomputing.com>
Cc: Gautam Menghani <gautammenghani201@gmail.com>
Cc: Steven Rostedt (Google) <rostedt@goodmis.org>
Cc: <stable@vger.kernel.org>    [6.2+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Yang Shi 2024-10-11 18:17:02 -07:00 committed by Andrew Morton
parent 2d6a1c8356
commit 37f0b47c51
2 changed files with 3 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
include/trace/events/huge_memory.h
View File

@ -208,7 +208,7 @@ TRACE_EVENT(mm_khugepaged_scan_file,
TRACE_EVENT(mm_khugepaged_collapse_file,
TP_PROTO(struct mm_struct *mm, struct folio *new_folio, pgoff_t index,
bool is_shmem, unsigned long addr, struct file *file,
unsigned long addr, bool is_shmem, struct file *file,
int nr, int result),
TP_ARGS(mm, new_folio, index, addr, is_shmem, file, nr, result),
TP_STRUCT__entry(
@ -233,7 +233,7 @@ TRACE_EVENT(mm_khugepaged_collapse_file,
__entry->result = result;
),
TP_printk("mm=%p, hpage_pfn=0x%lx, index=%ld, addr=%ld, is_shmem=%d, filename=%s, nr=%d, result=%s",
TP_printk("mm=%p, hpage_pfn=0x%lx, index=%ld, addr=%lx, is_shmem=%d, filename=%s, nr=%d, result=%s",
__entry->mm,
__entry->hpfn,
__entry->index,

2
mm/khugepaged.c
View File

@ -2227,7 +2227,7 @@ rollback:
folio_put(new_folio);
out:
VM_BUG_ON(!list_empty(&pagelist));
trace_mm_khugepaged_collapse_file(mm, new_folio, index, is_shmem, addr, file, HPAGE_PMD_NR, result);
trace_mm_khugepaged_collapse_file(mm, new_folio, index, addr, is_shmem, file, HPAGE_PMD_NR, result);
return result;
}