Re: [PATCH v3 01/13] mm, THP: don't hold mmap_sem in khugepaged when allocating THP

2014-06-23 Thread Zhang Yanfei
On 06/23/2014 05:52 PM, Vlastimil Babka wrote: > On 06/23/2014 07:39 AM, Zhang Yanfei wrote: >> Hello >> >> On 06/21/2014 01:45 AM, Kirill A. Shutemov wrote: >>> On Fri, Jun 20, 2014 at 05:49:31PM +0200, Vlastimil Babka wrote: When allocating huge page for collapsing, khugepaged currently hold

Re: [PATCH v3 01/13] mm, THP: don't hold mmap_sem in khugepaged when allocating THP

2014-06-23 Thread Vlastimil Babka
On 06/23/2014 07:39 AM, Zhang Yanfei wrote: Hello On 06/21/2014 01:45 AM, Kirill A. Shutemov wrote: On Fri, Jun 20, 2014 at 05:49:31PM +0200, Vlastimil Babka wrote: When allocating huge page for collapsing, khugepaged currently holds mmap_sem for reading on the mm where collapsing occurs. Afte

Re: [PATCH v3 01/13] mm, THP: don't hold mmap_sem in khugepaged when allocating THP

2014-06-22 Thread Zhang Yanfei
Hello On 06/21/2014 01:45 AM, Kirill A. Shutemov wrote: > On Fri, Jun 20, 2014 at 05:49:31PM +0200, Vlastimil Babka wrote: >> When allocating huge page for collapsing, khugepaged currently holds mmap_sem >> for reading on the mm where collapsing occurs. Afterwards the read lock is >> dropped befor

Re: [PATCH v3 01/13] mm, THP: don't hold mmap_sem in khugepaged when allocating THP

2014-06-20 Thread Kirill A. Shutemov
On Fri, Jun 20, 2014 at 05:49:31PM +0200, Vlastimil Babka wrote: > When allocating huge page for collapsing, khugepaged currently holds mmap_sem > for reading on the mm where collapsing occurs. Afterwards the read lock is > dropped before write lock is taken on the same mmap_sem. > > Holding mmap_