The patch titled cgroups: update documentation of cgroups tasks and procs files has been added to the -mm tree. Its filename is cgroups-update-documentation-of-cgroups-tasks-and-procs-files.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** See http://userweb.kernel.org/~akpm/stuff/added-to-mm.txt to find out what to do about this The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/ ------------------------------------------------------ Subject: cgroups: update documentation of cgroups tasks and procs files From: Paul Menage <menage@xxxxxxxxxx> Update documentation of cgroups tasks and procs files Document the cgroup.procs file. Clarify the semantics of the cgroup.procs and tasks files. Although the current cgroup.procs interface returns a sorted and uniqified list of pids, potential future performance enhancements could result in those properties being removed - explicitly document this aspect of the API. There are no existing users of cgroup.procs, so compatibility isn't an issue. There are users of the "tasks" file, but none that would appear to break in the event of the sorted property being broken. The standard "libcpuset" explicitly sorts the results of reading from the tasks file, and "libcg" and other users don't appear to care about ordering. Signed-off-by: Paul Menage <menage@xxxxxxxxxx> Reviewed-by: Li Zefan <lizf@xxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- Documentation/cgroups/cgroups.txt | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff -puN Documentation/cgroups/cgroups.txt~cgroups-update-documentation-of-cgroups-tasks-and-procs-files Documentation/cgroups/cgroups.txt --- a/Documentation/cgroups/cgroups.txt~cgroups-update-documentation-of-cgroups-tasks-and-procs-files +++ a/Documentation/cgroups/cgroups.txt @@ -227,7 +227,14 @@ as the path relative to the root of the Each cgroup is represented by a directory in the cgroup file system containing the following files describing that cgroup: - - tasks: list of tasks (by pid) attached to that cgroup + - tasks: list of tasks (by pid) attached to that cgroup. This list + is not guaranteed to be sorted. Writing a thread id into this file + moves the thread into this cgroup. + - cgroup.procs: list of tgids in the cgroup. This list is not + guaranteed to be sorted or free of duplicate tgids, and userspace + should sort/uniquify the list if this property is required. + Writing a tgid into this file moves all threads with that tgid into + this cgroup. - notify_on_release flag: run the release agent on exit? - release_agent: the path to use for release notifications (this file exists in the top cgroup only) @@ -374,7 +381,7 @@ Now you want to do something with this c In this directory you can find several files: # ls -notify_on_release tasks +cgroup.procs notify_on_release tasks (plus whatever files added by the attached subsystems) Now attach your shell to this cgroup: _ Patches currently in -mm which might be from menage@xxxxxxxxxx are origin.patch cgroups-update-documentation-of-cgroups-tasks-and-procs-files.patch add-a-refcount-check-in-dput.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html