No subject
Baoquan He
bhe at redhat.com
Sun Nov 24 21:11:17 EST 2013
kumagai-atsushi at mxc.nes.nec.co.jp
Bcc: bhe at redhat.com
Subject: Re: [PATCH v2] makedumpfile: add parameters to update_cyclic_region
Reply-To:
In-Reply-To: <20131123092914.GA31384 at dhcp-16-105.nay.redhat.com>
I think v2 is better than v1, since update_cyclic_region can be used
with a more flexible calling.
Hi HATAYAMA and Atsushi,
What's your opinion about this?
Baoquan
Thanks a lot
On 11/23/13 at 05:29pm, Baoquan He wrote:
> Function update_cyclic_region has a name which doesn't match its
> functionality. it does 3 tings: update the cyclic region; if elf
> dump, call create_1st_bitmap_cyclic in this region; call
> exclude_unnecessary_pages_cyclic to exclude pages in this region.
>
> However not all 3 things are needed to be done everywhere. Somewhere
> unnecessary thing is done with much efforts, e.g when get dumpable
> page numbers for elf cyclic dump 1st bigmap creating is not needed.
> Somewhere thing is done, but it also cause errors, e.g when write
> 1st bitmap cyclic for compressed kdump it will add free page numbers
> twice, namely pfn_free is doubled. Then dump information will be wrong
> like below:
>
> Original pages : 0x000000000007539c
> Excluded pages : 0x00000000000d986a
> Pages filled with zero : 0x0000000000001196
> Cache pages : 0x0000000000025008
> Cache pages + private : 0x0000000000004baa
> User process data pages : 0x00000000000127d0
> Free pages : 0x000000000009c352
> Hwpoison pages : 0x0000000000000000
> Remaining pages : 0xfffffffffff9bb32
> (The number of pages is reduced to 38418230895101%.)
> Memory Hole : 0x000000000000ac62
> --------------------------------------------------
> Total pages : 0x000000000007fffe
>
> So add 2 more parameters for update_cyclic_region. By these adding
> update_cyclic_region can be called in a refined grain. Then effort
> can be saved and above error can be fixed.
>
> And in kdump compressed dump case, prepare_bitmap2_buffer_cyclic is
> called, that means partial_bitmap2 is malloced twice. Here remove
> the 2nd call.
> ---
> makedumpfile.c | 21 +++++++++------------
> 1 file changed, 9 insertions(+), 12 deletions(-)
>
> diff --git a/makedumpfile.c b/makedumpfile.c
> index 3746cf6..8cfc2a5 100644
> --- a/makedumpfile.c
> +++ b/makedumpfile.c
> @@ -4725,7 +4725,7 @@ exclude_unnecessary_pages_cyclic(void)
> }
>
> int
> -update_cyclic_region(unsigned long long pfn)
> +update_cyclic_region(unsigned long long pfn, int bmp1_set, int exclude)
> {
> if (is_cyclic_region(pfn))
> return TRUE;
> @@ -4736,10 +4736,10 @@ update_cyclic_region(unsigned long long pfn)
> if (info->cyclic_end_pfn > info->max_mapnr)
> info->cyclic_end_pfn = info->max_mapnr;
>
> - if (info->flag_elf_dumpfile && !create_1st_bitmap_cyclic())
> + if (bmp1_set && info->flag_elf_dumpfile && !create_1st_bitmap_cyclic())
> return FALSE;
>
> - if (!exclude_unnecessary_pages_cyclic())
> + if (exclude && !exclude_unnecessary_pages_cyclic())
> return FALSE;
>
> return TRUE;
> @@ -5502,7 +5502,7 @@ get_num_dumpable_cyclic(void)
> unsigned long long pfn, num_dumpable=0;
>
> for (pfn = 0; pfn < info->max_mapnr; pfn++) {
> - if (!update_cyclic_region(pfn))
> + if (!update_cyclic_region(pfn, 0, 1))
> return FALSE;
>
> if (is_dumpable_cyclic(info->partial_bitmap2, pfn))
> @@ -5803,7 +5803,7 @@ get_loads_dumpfile_cyclic(void)
> * Update target region and bitmap
> */
> if (!is_cyclic_region(pfn)) {
> - if (!update_cyclic_region(pfn))
> + if (!update_cyclic_region(pfn, 0, 1))
> return FALSE;
> }
>
> @@ -5872,7 +5872,7 @@ write_elf_pages_cyclic(struct cache_data *cd_header, struct cache_data *cd_page)
>
> info->cyclic_start_pfn = 0;
> info->cyclic_end_pfn = 0;
> - if (!update_cyclic_region(0))
> + if (!update_cyclic_region(0, 1, 1))
> return FALSE;
>
> if (!(phnum = get_phnum_memory()))
> @@ -5910,7 +5910,7 @@ write_elf_pages_cyclic(struct cache_data *cd_header, struct cache_data *cd_page)
> /*
> * Update target region and partial bitmap if necessary.
> */
> - if (!update_cyclic_region(pfn))
> + if (!update_cyclic_region(pfn, 1, 1))
> return FALSE;
>
> if (!is_dumpable_cyclic(info->partial_bitmap2, pfn)) {
> @@ -6805,7 +6805,7 @@ write_kdump_pages_and_bitmap_cyclic(struct cache_data *cd_header, struct cache_d
> for (pfn = 0; pfn < info->max_mapnr; pfn++) {
> if (is_cyclic_region(pfn))
> continue;
> - if (!update_cyclic_region(pfn))
> + if (!update_cyclic_region(pfn, 0, 0))
> return FALSE;
> if (!create_1st_bitmap_cyclic())
> return FALSE;
> @@ -6815,9 +6815,6 @@ write_kdump_pages_and_bitmap_cyclic(struct cache_data *cd_header, struct cache_d
>
> free_bitmap1_buffer();
>
> - if (!prepare_bitmap2_buffer_cyclic())
> - return FALSE;
> -
> /*
> * Write pages and bitmap cyclically.
> */
> @@ -6827,7 +6824,7 @@ write_kdump_pages_and_bitmap_cyclic(struct cache_data *cd_header, struct cache_d
> if (is_cyclic_region(pfn))
> continue;
>
> - if (!update_cyclic_region(pfn))
> + if (!update_cyclic_region(pfn, 0, 1))
> return FALSE;
>
> if (!write_kdump_pages_cyclic(cd_header, cd_page, &pd_zero, &offset_data))
> --
> 1.8.3.1
>
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