mm/khugepaged: add tracepoint to collapse_file()

"mm_khugepaged_collapse_file" for capturing is_shmem.
Currently, is_shmem is not being captured. Capturing is_shmem is useful
as it can indicate if tmpfs is being used as a backing store instead of
persistent storage. Add the tracepoint in collapse_file() named
"mm_khugepaged_collapse_file" for capturing is_shmem.

[gautammenghani201@gmail.com: swap is_shmem and addr to save space, per Steven Rostedt]
  Link: https://lkml.kernel.org/r/20221202201807.182829-1-gautammenghani201@gmail.com
Link: https://lkml.kernel.org/r/20221026052218.148234-1-gautammenghani201@gmail.com
Signed-off-by: Gautam Menghani <gautammenghani201@gmail.com>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>	[tracing]
Cc: David Hildenbrand <david@redhat.com>
Cc: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zach O'Keefe <zokeefe@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Gautam Menghani 2022-10-26 10:52:18 +05:30 committed by Andrew Morton
parent f7355e99d9
commit 4c9473e87e
2 changed files with 42 additions and 3 deletions

View File

@ -203,5 +203,43 @@ TRACE_EVENT(mm_khugepaged_scan_file,
__print_symbolic(__entry->result, SCAN_STATUS))
);
TRACE_EVENT(mm_khugepaged_collapse_file,
TP_PROTO(struct mm_struct *mm, struct page *hpage, pgoff_t index,
bool is_shmem, unsigned long addr, struct file *file,
int nr, int result),
TP_ARGS(mm, hpage, index, addr, is_shmem, file, nr, result),
TP_STRUCT__entry(
__field(struct mm_struct *, mm)
__field(unsigned long, hpfn)
__field(pgoff_t, index)
__field(unsigned long, addr)
__field(bool, is_shmem)
__string(filename, file->f_path.dentry->d_iname)
__field(int, nr)
__field(int, result)
),
TP_fast_assign(
__entry->mm = mm;
__entry->hpfn = hpage ? page_to_pfn(hpage) : -1;
__entry->index = index;
__entry->addr = addr;
__entry->is_shmem = is_shmem;
__assign_str(filename, file->f_path.dentry->d_iname);
__entry->nr = nr;
__entry->result = result;
),
TP_printk("mm=%p, hpage_pfn=0x%lx, index=%ld, addr=%ld, is_shmem=%d, filename=%s, nr=%d, result=%s",
__entry->mm,
__entry->hpfn,
__entry->index,
__entry->addr,
__entry->is_shmem,
__get_str(filename),
__entry->nr,
__print_symbolic(__entry->result, SCAN_STATUS))
);
#endif /* __HUGE_MEMORY_H */
#include <trace/define_trace.h>

View File

@ -1744,12 +1744,12 @@ static int collapse_file(struct mm_struct *mm, unsigned long addr,
{
struct address_space *mapping = file->f_mapping;
struct page *hpage;
pgoff_t index, end = start + HPAGE_PMD_NR;
pgoff_t index = 0, end = start + HPAGE_PMD_NR;
LIST_HEAD(pagelist);
XA_STATE_ORDER(xas, &mapping->i_pages, start, HPAGE_PMD_ORDER);
int nr_none = 0, result = SCAN_SUCCEED;
bool is_shmem = shmem_file(file);
int nr;
int nr = 0;
VM_BUG_ON(!IS_ENABLED(CONFIG_READ_ONLY_THP_FOR_FS) && !is_shmem);
VM_BUG_ON(start & (HPAGE_PMD_NR - 1));
@ -2102,7 +2102,8 @@ out:
mem_cgroup_uncharge(page_folio(hpage));
put_page(hpage);
}
/* TODO: tracepoints */
trace_mm_khugepaged_collapse_file(mm, hpage, index, is_shmem, addr, file, nr, result);
return result;
}