> -----Original Message----- > From: containers-boun...@lists.linux-foundation.org > [mailto:containers-boun...@lists.linux-foundation.org] On Behalf Of Chen > Hanxiao > Sent: Monday, December 01, 2014 7:06 PM > To: Eric W. Biederman; Serge Hallyn; Oleg Nesterov; Richard Weinberger; Andrew > Morton > Cc: contain...@lists.linux-foundation.org; linux-kernel@vger.kernel.org; > Mateusz Guzik; David Howells > Subject: [PATCH v9 1/3] procfs: show hierarchy of pid namespace > > We lack of pid hierarchy information, and this will lead to: > a) we don't know pids' relationship, who is whose child: > /proc/PID/ns/pid only tell us whether two pids live in different ns > b) bring trouble to nested lxc container check/restore/migration > c) bring trouble to pid translation between containers; > > This patch will show the hierarchy of pid namespace > by pidns_hierarchy like: > > <init_PID> <parent_of_init_PID> <relative PID level> > > Ex: > [root@localhost ~]#cat /proc/pidns_hierarchy > 18060 1 1 > 18102 18060 2 > 1534 18102 3 > 1600 18102 3 > 1550 1 1 > *Note: numbers represent the pid 1 in different ns > > It shows the pid hierarchy below: > > init_pid_ns 1 > │ > ┌────────────┐ > ns1 ns2 > │ │ > 1550 18060 > │ > │ > ns3 > │ > 18102 > │ > ┌──────────┐ > ns4 ns5 > │ │ > 1534 1600 > > Every pid printed in pidns_hierarchy > is the init pid of that pid ns level. > > Acked-by: Richard Weinberer <rich...@nod.at> > > Signed-off-by: Chen Hanxiao <chenhanx...@cn.fujitsu.com> > --- > v9: fix codes be included if CONFIG_PID_NS=n > v8: use max() from kernel.h > fix some improper comments > v7: change stype to be consistent with current interface like > <init_PID> <parent_of_init_PID> <relative PID level> > remove EXPERT dependent in Kconfig > v6: fix a get_pid leak and do some cleanups; > v5: collect pid by find_ge_pid; > use local list inside nslist_proc_show; > use get_pid, remove mutex lock. > v4: simplify pid collection and some performance optimizamtion > fix another race issue. > v3: fix a race issue and memory leak issue > v2: use a procfs text file instead of dirs under /proc >
Hi, Any comments? Thanks, - Chen
