[Patch v3 7/7] add a new interface to show the memory usage of 1st kernel

[Atsushi Kumagai]

>On 08/01/14 at 07:12am, Atsushi Kumagai wrote:
>> >Page number of memory in different use
>> >--------------------------------------------------
>> >TYPE		PAGES			EXCLUDABLE	DESCRIPTION
>> >ZERO		0               	yes		Pages filled with zero
>>
>> The number of zero pages is always 0 since it isn't counted during
>> get_num_dumpable_cyclic(). To count it up, we have to read all of the
>> pages like exclude_zero_pages(), so we need "exclude_zero_pages_cyclic()".
>> My idea is to call it in get_num_dumpable_cyclic() like:
>>
>> 		for_each_cycle(0, info->max_mapnr, &cycle)
>> 		{
>> 				if (!exclude_unnecessary_pages_cyclic(&cycle))
>> 					return FALSE;
>>
>> +				if (info->flag_mem_usage)
>> +					exclude_zero_pages_cyclic(&cycle);
>> +
>> 				for(pfn=cycle.start_pfn; pfn<cycle.end_pfn; pfn++)
>
>
>Hi Atsushi,
>
>I just introduced a new function exclude_zero_pages_cyclic as you
>suggested. But it always exited with below message. I don't know what's
>wrong with this function. Could you help have a look at it?
>
>"Program terminated with signal SIGKILL"

Umm, the code looks no problem and it works well at least on my
machine (x86_64 on KVM), so I have no idea for now.

Can strace and audit help your investigation? They may provide
some hints (e.g. Who send SIGKILL) for us.


Thanks
Atsushi Kumagai

>From: Baoquan He <bhe at redhat.com>
>Date: Thu, 21 Aug 2014 13:29:31 +0800
>Subject: [PATCH] introduce a function exclude_zero_pages_cyclic()
>
>Introduced a new function exclude_zero_pages_cyclic(), this will
>exclude and counting zero pages. Calling it in get_num_dumpable_cyclic
>can get the number of zero pages.
>
>Signed-off-by: Baoquan He <bhe at redhat.com>
>---
> makedumpfile.c | 42 ++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 42 insertions(+)
>
>diff --git a/makedumpfile.c b/makedumpfile.c
>index d43d02d..a511179 100644
>--- a/makedumpfile.c
>+++ b/makedumpfile.c
>@@ -4582,6 +4582,45 @@ exclude_zero_pages(void)
> 	return TRUE;
> }
>
>+int
>+exclude_zero_pages_cyclic(struct cycle *cycle)
>+{
>+	mdf_pfn_t pfn;
>+	unsigned long long paddr;
>+	unsigned char buf[info->page_size];
>+
>+	for (pfn = cycle->start_pfn, paddr = pfn_to_paddr(pfn); pfn < cycle->end_pfn;
>+	    pfn++, paddr += info->page_size) {
>+
>+		if (!is_in_segs(paddr))
>+			continue;
>+
>+		if (!is_dumpable_cyclic(info->partial_bitmap2, pfn, cycle))
>+			continue;
>+
>+		if (is_xen_memory()) {
>+			if (!readmem(MADDR_XEN, paddr, buf, info->page_size)) {
>+				ERRMSG("Can't get the page data(pfn:%llx, max_mapnr:%llx).\n",
>+				    pfn, info->max_mapnr);
>+				return FALSE;
>+			}
>+		} else {
>+			if (!readmem(PADDR, paddr, buf, info->page_size)) {
>+				ERRMSG("Can't get the page data(pfn:%llx, max_mapnr:%llx).\n",
>+				    pfn, info->max_mapnr);
>+				return FALSE;
>+			}
>+		}
>+		if (is_zero_page(buf, info->page_size)) {
>+			if (clear_bit_on_2nd_bitmap(pfn, cycle))
>+				pfn_zero++;
>+		}
>+	}
>+
>+	return TRUE;
>+}
>+
>+
> static int
> initialize_2nd_bitmap_cyclic(struct cycle *cycle)
> {
>@@ -5662,6 +5701,9 @@ get_num_dumpable_cyclic(void)
> 		if (!exclude_unnecessary_pages_cyclic(&cycle))
> 			return FALSE;
>
>+		if (info->flag_mem_usage)
>+			exclude_zero_pages_cyclic(&cycle);
>+
> 		for(pfn=cycle.start_pfn; pfn<cycle.end_pfn; pfn++)
> 			if (is_dumpable_cyclic(info->partial_bitmap2, pfn, &cycle))
> 				num_dumpable++;
>--
>1.8.5.3