Re: [RFC PATCH v4 11/13] memory-hotplug : free memmap of sparse-vmemmap

2012-07-19 Thread Yasuaki Ishimatsu
Hi Wen, 2012/07/19 14:58, Wen Congyang wrote: At 07/18/2012 06:16 PM, Yasuaki Ishimatsu Wrote: All pages of virtual mapping in removed memory cannot be freed, since some pages used as PGD/PUD includes not only removed memory but also other memory. So the patch checks whether page can be

[RESEND RFC PATCH v4 11/13] memory-hotplug : free memmap of sparse-vmemmap

2012-07-19 Thread Yasuaki Ishimatsu
All pages of virtual mapping in removed memory cannot be freed, since some pages used as PGD/PUD includes not only removed memory but also other memory. So the patch checks whether page can be freed or not. How to check whether page can be freed or not? 1. When removing memory, the page structs

Re: [RFC PATCH v4 11/13] memory-hotplug : free memmap of sparse-vmemmap

2012-07-19 Thread Wen Congyang
At 07/18/2012 06:16 PM, Yasuaki Ishimatsu Wrote: All pages of virtual mapping in removed memory cannot be freed, since some pages used as PGD/PUD includes not only removed memory but also other memory. So the patch checks whether page can be freed or not. How to check whether page can be

Re: [RFC PATCH v4 11/13] memory-hotplug : free memmap of sparse-vmemmap

2012-07-19 Thread Yasuaki Ishimatsu
Hi Wen, 2012/07/19 18:45, Wen Congyang wrote: At 07/18/2012 06:16 PM, Yasuaki Ishimatsu Wrote: All pages of virtual mapping in removed memory cannot be freed, since some pages used as PGD/PUD includes not only removed memory but also other memory. So the patch checks whether page can be

Re: [RFC PATCH v4 11/13] memory-hotplug : free memmap of sparse-vmemmap

2012-07-19 Thread Wen Congyang
At 07/19/2012 05:45 PM, Wen Congyang Wrote: At 07/18/2012 06:16 PM, Yasuaki Ishimatsu Wrote: All pages of virtual mapping in removed memory cannot be freed, since some pages used as PGD/PUD includes not only removed memory but also other memory. So the patch checks whether page can be

[RFC PATCH v4 11/13] memory-hotplug : free memmap of sparse-vmemmap

2012-07-18 Thread Yasuaki Ishimatsu
All pages of virtual mapping in removed memory cannot be freed, since some pages used as PGD/PUD includes not only removed memory but also other memory. So the patch checks whether page can be freed or not. How to check whether page can be freed or not? 1. When removing memory, the page structs

Re: [RFC PATCH v4 11/13] memory-hotplug : free memmap of sparse-vmemmap

2012-07-18 Thread Wen Congyang
At 07/18/2012 06:16 PM, Yasuaki Ishimatsu Wrote: All pages of virtual mapping in removed memory cannot be freed, since some pages used as PGD/PUD includes not only removed memory but also other memory. So the patch checks whether page can be freed or not. How to check whether page can be