> -----Original Message-----
> The -E option, which creates a dumpfile in ELF format, reports wrong
> statistics like the ones below, because:
> (1) counts excluded pages repeatedly due to overlapped cycles
> (2) does not calculate the number of memory hole pages in cyclic mode
> (3) does not take account of the number of pages excluded actually
> in ELF format, which excludes only contiguous 256 or more pages
> that can be excluded.
>
> Original pages : 0x0000000000000000
> Excluded pages : 0x00000000007daf05
> Pages filled with zero : 0x0000000000002dcc
> Non-private cache pages : 0x00000000000471d6
> Private cache pages : 0x0000000000000001
> User process data pages : 0x00000000000147f1
> Free pages : 0x000000000077c771
> Hwpoison pages : 0x0000000000000000
> Offline pages : 0x0000000000000000
> Remaining pages : 0xffffffffff8250fb
> Memory Hole : 0x0000000000440000
> --------------------------------------------------
> Total pages : 0x0000000000440000
>
> In order to fix this issue:
> (1) start the first cycle from the start pfn of a segment to avoid
> overlaps between cycles
finally I found a fault with this change.
Will merge the following patch into the original one.
diff --git a/makedumpfile.c b/makedumpfile.c
index 9569251ce0c7..ac19ed858416 100644
--- a/makedumpfile.c
+++ b/makedumpfile.c
@@ -56,8 +56,13 @@ static void first_cycle(mdf_pfn_t start, mdf_pfn_t max, struct cycle *cycle)
if (cycle->end_pfn > max)
cycle->end_pfn = max;
+ /*
+ * Mitigate statistics problem in ELF dump mode.
+ * A cycle must start with a pfn that is divisible by BITPERBYTE.
+ * See create_bitmap_from_memhole().
+ */
if (info->flag_elf_dumpfile && cycle->start_pfn < start)
- cycle->start_pfn = start;
+ cycle->start_pfn = round(start, BITPERBYTE);
cycle->exclude_pfn_start = 0;
cycle->exclude_pfn_end = 0;
@@ -7503,7 +7508,7 @@ get_loads_dumpfile_cyclic(void)
if (!create_2nd_bitmap(&cycle))
return FALSE;
}
- for (pfn = cycle.start_pfn; pfn < cycle.end_pfn; pfn++) {
+ for (pfn = MAX(pfn_start, cycle.start_pfn); pfn < cycle.end_pfn; pfn++) {
if (!is_dumpable(info->bitmap2, pfn, &cycle)) {
num_excluded++;
continue;
@@ -7598,7 +7603,7 @@ write_elf_pages_cyclic(struct cache_data *cd_header, struct cache_data *cd_page)
return FALSE;
}
- for (pfn = cycle.start_pfn; pfn < cycle.end_pfn; pfn++) {
+ for (pfn = MAX(pfn_start, cycle.start_pfn); pfn < cycle.end_pfn; pfn++) {
if (info->flag_cyclic)
pfn_memhole--;
Thanks,
Kazu
> (2) calculate the number of memory hole pages in cyclic mode
> (3) introduce pfn_elf_excluded variable to store the actual number
> of the excluded pages in ELF format
>
> With the patch, a report message in ELF format mode becomes like this:
>
> Original pages : 0x00000000003f1538
> Excluded pages : 0x00000000003c8c9d
> in ELF format : 0x00000000003c4319
> Pages filled with zero : 0x00000000000026d8
> Non-private cache pages : 0x0000000000047032
> Private cache pages : 0x0000000000000001
> User process data pages : 0x0000000000014794
> Free pages : 0x000000000036adfe
> Hwpoison pages : 0x0000000000000000
> Offline pages : 0x0000000000000000
> Remaining pages : 0x000000000002889b
> in ELF format : 0x000000000002d21f
> (The number of pages is reduced to 4%.)
> Memory Hole : 0x000000000004eac8
> --------------------------------------------------
> Total pages : 0x0000000000440000
>
> where the "Excluded pages" and "Remaining pages" do not mean the
> actual numbers of excluded and remaining pages. But remain the
> same for some reference.
>
> Signed-off-by: Kazuhito Hagio <k-hagio@xxxxxxxxxxxxx>
> ---
> makedumpfile.c | 27 +++++++++++++++++++++++++--
> 1 file changed, 25 insertions(+), 2 deletions(-)
>
> diff --git a/makedumpfile.c b/makedumpfile.c
> index 4a000112ba59..9569251ce0c7 100644
> --- a/makedumpfile.c
> +++ b/makedumpfile.c
> @@ -56,6 +56,9 @@ static void first_cycle(mdf_pfn_t start, mdf_pfn_t max, struct cycle *cycle)
> if (cycle->end_pfn > max)
> cycle->end_pfn = max;
>
> + if (info->flag_elf_dumpfile && cycle->start_pfn < start)
> + cycle->start_pfn = start;
> +
> cycle->exclude_pfn_start = 0;
> cycle->exclude_pfn_end = 0;
> }
> @@ -89,6 +92,7 @@ mdf_pfn_t pfn_user;
> mdf_pfn_t pfn_free;
> mdf_pfn_t pfn_hwpoison;
> mdf_pfn_t pfn_offline;
> +mdf_pfn_t pfn_elf_excluded;
>
> mdf_pfn_t num_dumped;
>
> @@ -7499,7 +7503,7 @@ get_loads_dumpfile_cyclic(void)
> if (!create_2nd_bitmap(&cycle))
> return FALSE;
> }
> - for (pfn = MAX(pfn_start, cycle.start_pfn); pfn < cycle.end_pfn; pfn++) {
> + for (pfn = cycle.start_pfn; pfn < cycle.end_pfn; pfn++) {
> if (!is_dumpable(info->bitmap2, pfn, &cycle)) {
> num_excluded++;
> continue;
> @@ -7594,7 +7598,10 @@ write_elf_pages_cyclic(struct cache_data *cd_header, struct cache_data *cd_page)
> return FALSE;
> }
>
> - for (pfn = MAX(pfn_start, cycle.start_pfn); pfn < cycle.end_pfn; pfn++) {
> + for (pfn = cycle.start_pfn; pfn < cycle.end_pfn; pfn++) {
> + if (info->flag_cyclic)
> + pfn_memhole--;
> +
> if (!is_dumpable(info->bitmap2, pfn, &cycle)) {
> num_excluded++;
> if ((pfn == pfn_end - 1) && frac_tail)
> @@ -7639,6 +7646,9 @@ write_elf_pages_cyclic(struct cache_data *cd_header, struct cache_data *cd_page)
> continue;
> }
>
> + /* The number of pages excluded actually in ELF format */
> + pfn_elf_excluded += num_excluded;
> +
> /*
> * If the number of the contiguous pages to be excluded
> * is 256 or more, those pages are excluded really.
> @@ -7691,6 +7701,9 @@ write_elf_pages_cyclic(struct cache_data *cd_header, struct cache_data *cd_page)
> }
> }
>
> + /* The number of pages excluded actually in ELF format */
> + pfn_elf_excluded += num_excluded;
> +
> /*
> * Write the last PT_LOAD.
> */
> @@ -9777,6 +9790,9 @@ print_report(void)
> REPORT_MSG("\n");
> REPORT_MSG("Original pages : 0x%016llx\n", pfn_original);
> REPORT_MSG(" Excluded pages : 0x%016llx\n", pfn_excluded);
> + if (info->flag_elf_dumpfile)
> + REPORT_MSG(" in ELF format : 0x%016llx\n",
> + pfn_elf_excluded);
> REPORT_MSG(" Pages filled with zero : 0x%016llx\n", pfn_zero);
> REPORT_MSG(" Non-private cache pages : 0x%016llx\n", pfn_cache);
> REPORT_MSG(" Private cache pages : 0x%016llx\n",
> @@ -9788,6 +9804,13 @@ print_report(void)
> REPORT_MSG(" Remaining pages : 0x%016llx\n",
> pfn_original - pfn_excluded);
>
> + if (info->flag_elf_dumpfile) {
> + REPORT_MSG(" in ELF format : 0x%016llx\n",
> + pfn_original - pfn_elf_excluded);
> +
> + pfn_excluded = pfn_elf_excluded;
> + }
> +
> if (pfn_original != 0) {
> shrinking = (pfn_original - pfn_excluded) * 100;
> shrinking = shrinking / pfn_original;
> --
> 2.18.1
>
>
>
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