From: Zhou Wenjian <zhouwj-fnst@xxxxxxxxxxxxxx>
Subject: [PATCH v2 1/5] Add support for splitblock
Date: Mon, 13 Oct 2014 17:34:22 +0800
> When --split option is specified, fair I/O workloads shoud be assigned
> for each process. So the start and end pfn of each dumpfile should be
> calculated with excluding unnecessary pages. However, it costs a lot of
> time to execute excluding for the whole memory. That is why struct
> SplitBlock exists. Struct SplitBlock is designed to manage memory, mainly
> for recording the number of dumpable pages. We can use the number of
> dumpable pages to calculate start and end pfn instead of execute excluding
> for the whole memory.
>
> The char array *table in struct SplitBlock is used to record the number of
> dumpable pages.
> The table entry size is calculated as
> divideup(log2(splitblock_size / page_size), 8) bytes
> The table entry size is calculated, so that the
> space table taken will be small enough. And the code will also have a
> good performence when the number of pages in one splitblock is big enough.
>
> Signed-off-by: Qiao Nuohan <qiaonuohan at cn.fujitsu.com>
> Signed-off-by: Zhou Wenjian <zhouwj-fnst at cn.fujitsu.com>
> ---
> makedumpfile.c | 23 +++++++++++++++++++++++
> makedumpfile.h | 14 ++++++++++++++
> 2 files changed, 37 insertions(+), 0 deletions(-)
>
> diff --git a/makedumpfile.c b/makedumpfile.c
> index b4d43d8..95d553c 100644
> --- a/makedumpfile.c
> +++ b/makedumpfile.c
> @@ -34,6 +34,7 @@ struct srcfile_table srcfile_table;
>
> struct vm_table vt = { 0 };
> struct DumpInfo *info = NULL;
> +struct SplitBlock *splitblock = NULL;
>
> char filename_stdout[] = FILENAME_STDOUT;
>
> @@ -5685,6 +5686,28 @@ out:
> return ret;
> }
>
> +/*
> + * cyclic_split mode:
> + * manage memory by splitblocks,
> + * divide memory into splitblocks
> + * use splitblock_table to record numbers of dumpable pages in each splitblock
> + */
> +
> +//calculate entry size based on the amount of pages in one splitblock
Please use /* */ style in comment just as other parts of makedumpfile
source codes.
> +int
> +calculate_entry_size(void){
Please add linebreak.
calculate_entry_size(void)
{
> + int entry_num = 1, count = 1;
> + int entry_size;
Please add linebreak.
> + while (entry_num < splitblock->page_per_splitblock){
> + entry_num = entry_num << 1;
> + count++;
> + }
> + entry_size = count/BITPERBYTE;
> + if (count %BITPERBYTE)
> + entry_size++;
> + return entry_size;
> +}
> +
> mdf_pfn_t
> get_num_dumpable(void)
> {
> diff --git a/makedumpfile.h b/makedumpfile.h
> index 96830b0..98b8404 100644
> --- a/makedumpfile.h
> +++ b/makedumpfile.h
> @@ -1168,10 +1168,24 @@ struct DumpInfo {
> */
> int (*page_is_buddy)(unsigned long flags, unsigned int _mapcount,
> unsigned long private, unsigned int _count);
> + /*
> + *for cyclic_splitting mode, setup splitblock_size
> + */
> + long long splitblock_size;
> };
> extern struct DumpInfo *info;
>
> /*
> + *for cyclic_splitting mode,Manage memory by splitblock
> + */
> +struct SplitBlock{
> + char *table;
> + long long num;
> + long long page_per_splitblock;
> + int entry_size; //counted by byte
Please use /* */.
> +};
> +
> +/*
> * kernel VM-related data
> */
> struct vm_table {
> --
> 1.7.1
>
>
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--
Thanks.
HATAYAMA, Daisuke
