Hi Johannes,
On 05/01/2013 12:32 AM, Johannes Weiner wrote:
On Sat, Apr 27, 2013 at 02:20:54PM +0800, Mtrr Patt wrote:
cc linux-mm
On 04/27/2013 02:19 PM, Mtrr Patt wrote:
Hi Johannes,
http://lwn.net/Articles/495543/
This link said that "When active pages are considered for
eviction, they are first moved to the inactive list and unmapped
>from the address space of the process(es) using them. Thus, once a
page moves to the inactive list, any attempt to reference it will
generate a page fault; this "soft fault" will cause the page to be
removed back to the active list."
Why I can't find the codes unmap during page moved from active
list to inactive list?
Most architectures have the hardware track the referenced bit in the
page tables, but some don't. For them, page_referenced_one() will
mark the mapping read-only when clearing the referenced/young bit and
the page fault handler will set the bit manually.
Thanks for your response. ;-) So the article is not against more common
case, isn't it?
When mapped pages reach the end of the inactive list and have that bit
set, they get activated, see page_check_references().
It seems that the page should trigger page fault twice and
page_check_references can active it.
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