• KAMEZAWA Hiroyuki's avatar
    memcg: fix OOM killer under memcg · 0b7f569e
    KAMEZAWA Hiroyuki authored
    This patch tries to fix OOM Killer problems caused by hierarchy.
    Now, memcg itself has OOM KILL function (in oom_kill.c) and tries to
    kill a task in memcg.
    
    But, when hierarchy is used, it's broken and correct task cannot
    be killed. For example, in following cgroup
    
    	/groupA/	hierarchy=1, limit=1G,
    		01	nolimit
    		02	nolimit
    All tasks' memory usage under /groupA, /groupA/01, groupA/02 is limited to
    groupA's 1Gbytes but OOM Killer just kills tasks in groupA.
    
    This patch provides makes the bad process be selected from all tasks
    under hierarchy. BTW, currently, oom_jiffies is updated against groupA
    in above case. oom_jiffies of tree should be updated.
    
    To see how oom_jiffies is used, please check mem_cgroup_oom_called()
    callers.
    
    [akpm@linux-foundation.org: build fix]
    [akpm@linux-foundation.org: const fix]
    Signed-off-by: default avatarKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
    Cc: Paul Menage <menage@google.com>
    Cc: Li Zefan <lizf@cn.fujitsu.com>
    Cc: Balbir Singh <balbir@in.ibm.com>
    Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
    Cc: David Rientjes <rientjes@google.com>
    Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
    Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
    0b7f569e
cgroup.c 93.3 KB