diff options
author | Ben Blum <bblum@google.com> | 2009-09-23 15:56:26 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2009-09-24 07:20:58 -0700 |
commit | 102a775e3647628727ae83a9a6abf0564c3ca7cb (patch) | |
tree | 77a3d9717daa0f1dceccc0dcdf821aa12e684e07 /include/linux/cgroup.h | |
parent | 8f3ff20862cfcb85500a2bb55ee64622bd59fd0c (diff) | |
download | op-kernel-dev-102a775e3647628727ae83a9a6abf0564c3ca7cb.zip op-kernel-dev-102a775e3647628727ae83a9a6abf0564c3ca7cb.tar.gz |
cgroups: add a read-only "procs" file similar to "tasks" that shows only unique tgids
struct cgroup used to have a bunch of fields for keeping track of the
pidlist for the tasks file. Those are now separated into a new struct
cgroup_pidlist, of which two are had, one for procs and one for tasks.
The way the seq_file operations are set up is changed so that just the
pidlist struct gets passed around as the private data.
Interface example: Suppose a multithreaded process has pid 1000 and other
threads with ids 1001, 1002, 1003:
$ cat tasks
1000
1001
1002
1003
$ cat cgroup.procs
1000
$
Signed-off-by: Ben Blum <bblum@google.com>
Signed-off-by: Paul Menage <menage@google.com>
Acked-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Matt Helsley <matthltc@us.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include/linux/cgroup.h')
-rw-r--r-- | include/linux/cgroup.h | 22 |
1 files changed, 14 insertions, 8 deletions
diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h index c833d6f..2357733 100644 --- a/include/linux/cgroup.h +++ b/include/linux/cgroup.h @@ -141,6 +141,17 @@ enum { CGRP_WAIT_ON_RMDIR, }; +struct cgroup_pidlist { + /* protects the other fields */ + struct rw_semaphore mutex; + /* array of xids */ + pid_t *list; + /* how many elements the above list has */ + int length; + /* how many files are using the current array */ + int use_count; +}; + struct cgroup { unsigned long flags; /* "unsigned long" so bitops work */ @@ -179,14 +190,9 @@ struct cgroup { */ struct list_head release_list; - /* pids_mutex protects the fields below */ - struct rw_semaphore pids_mutex; - /* Array of process ids in the cgroup */ - pid_t *tasks_pids; - /* How many files are using the current tasks_pids array */ - int pids_use_count; - /* Length of the current tasks_pids array */ - int pids_length; + /* we will have two separate pidlists, one for pids (the tasks file) + * and one for tgids (the procs file). */ + struct cgroup_pidlist tasks, procs; /* For RCU-protected deletion */ struct rcu_head rcu_head; |