Messages in this thread | | | Date | Wed, 10 Dec 2008 16:52:57 -0800 | Subject | Re: [RFC][PATCH 2/3] CGroups: Use hierarchy_mutex in memory controller | From | Paul Menage <> |
| |
On Wed, Dec 10, 2008 at 4:49 PM, KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> wrote: > > an operation like rmdir() in somewhere. > hierarchy_lock for A (acquired) > hierarchy_lock for B (waiting) > > in subsys A. > mmap_sem (acquired) > hierarchy_lock for A (waiting) > in subsys B. > hierarchy_lock for B (aquired) > mmap_sem (waiting) >
That's a valid deadlock - you'd need to require the mmap_sem nests either inside all hierarchy_mutexes or else outside all of them.
Paul
| |