9d9ec60cc49c36c64e695 parent b4d18311d37b0b1b370a1ef3e4de92b97930f0a8 author Tejun Heo 1350424995 -0700 committer Tejun Heo 1350775992 -0700 cgroup_freezer: don't use cgroup_lock_live_group() freezer_read/write() used cgroup_lock_live_group() to synchronize against task migration into and out of the target cgroup. cgroup_lock_live_group() grabs the internal cgroup lock and using it from outside cgroup core leads to complex and fragile locking dependency issues which are difficult to resolve. Now that freezer_can_attach() is replaced with freezer_attach() and update_if_frozen() updated, nothing requires excluding migration against freezer state reads and changes. This patch removes cgroup_lock_live_group() and the matching cgroup_unlock() usages. The prone-to-bitrot, already outdated and unnecessary global lock hierarchy documentation is replaced with documentation in local scope. Signed-off-by: Tejun Heo Cc: Oleg Nesterov Cc: Rafael J. Wysocki Cc: Li Zefan fw‚ž‘Cx