linux.git/fs/proc/array.c, branch v2.6.24

fix the "remove task_ppid_nr_ns" commit

2008-01-14T21:23:00+00:00

Commit 84427eaef1fb91704c7112bdb598c810003b99f3 (remove task_ppid_nr_ns)
moved the task_tgid_nr_ns(task->real_parent) outside of lock_task_sighand().
This is wrong, ->real_parent could be freed/reused.

Both ->parent/real_parent point to nothing after __exit_signal() because
we remove the child from ->children list, and thus the child can't be
reparented when its parent exits.

rcu_read_lock() protects ->parent/real_parent, but _only_ if we know it was
valid before we take rcu lock.

Revert this part of the patch.

Signed-off-by: Oleg Nesterov 
Signed-off-by: Linus Torvalds

remove task_ppid_nr_ns

2008-01-13T17:56:43+00:00

task_ppid_nr_ns is called in three places.  One of these should never
have called it.  In the other two, using it broke the existing
semantics.  This was presumably accidental.  If the function had not
been there, it would have been much more obvious to the eye that those
patches were changing the behavior.  We don't need this function.

In task_state, the pid of the ptracer is not the ppid of the ptracer.

In do_task_stat, ppid is the tgid of the real_parent, not its pid.
I also moved the call outside of lock_task_sighand, since it doesn't
need it.

In sys_getppid, ppid is the tgid of the real_parent, not its pid.

Signed-off-by: Roland McGrath 
Signed-off-by: Linus Torvalds

sched: fix prev_stime calculation

2007-11-26T20:21:49+00:00

Srivatsa Vaddagiri noticed occasionally incorrect CPU usage
values in top and tracked it down to stime going below 0 in
task_stime(). Negative values are possible there due to the
sampled nature of stime/utime.

Fix suggested by Balbir Singh.

Signed-off-by: Ingo Molnar 
Tested-by: Srivatsa Vaddagiri 
Reviewed-by: Balbir Singh

sched: fix /proc//stat stime/utime monotonicity, part 2

2007-10-29T23:26:32+00:00

Extend Peter's patch to fix accounting issues, by keeping stime
monotonic too.

Signed-off-by: Balbir Singh 
Signed-off-by: Ingo Molnar 
Tested-by: Frans Pop

sched: keep utime/stime monotonic

2007-10-29T20:18:11+00:00

keep utime/stime monotonic.

cpustats use utime/stime as a ratio against sum_exec_runtime, as a
consequence it can happen - when the ratio changes faster than time
accumulates - that either can be appear to go backwards.

Signed-off-by: Peter Zijlstra 
Signed-off-by: Ingo Molnar

Merge git://git.kernel.org/pub/scm/linux/kernel/git/mingo/linux-2.6-sched

2007-10-19T19:07:03+00:00

* git://git.kernel.org/pub/scm/linux/kernel/git/mingo/linux-2.6-sched:
  sched: fix guest time accounting going faster than user time accounting

Fix tsk->exit_state usage

2007-10-19T18:53:42+00:00

tsk->exit_state can only be 0, EXIT_ZOMBIE, or EXIT_DEAD.  A non-zero test
is the same as tsk->exit_state & (EXIT_ZOMBIE | EXIT_DEAD), so just testing
tsk->exit_state is sufficient.

Signed-off-by: Eugene Teo 
Cc: Roland McGrath 
Cc: Oleg Nesterov 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

pid namespaces: changes to show virtual ids to user

2007-10-19T18:53:40+00:00

This is the largest patch in the set. Make all (I hope) the places where
the pid is shown to or get from user operate on the virtual pids.

The idea is:
 - all in-kernel data structures must store either struct pid itself
   or the pid's global nr, obtained with pid_nr() call;
 - when seeking the task from kernel code with the stored id one
   should use find_task_by_pid() call that works with global pids;
 - when showing pid's numerical value to the user the virtual one
   should be used, but however when one shows task's pid outside this
   task's namespace the global one is to be used;
 - when getting the pid from userspace one need to consider this as
   the virtual one and use appropriate task/pid-searching functions.

[akpm@linux-foundation.org: build fix]
[akpm@linux-foundation.org: nuther build fix]
[akpm@linux-foundation.org: yet nuther build fix]
[akpm@linux-foundation.org: remove unneeded casts]
Signed-off-by: Pavel Emelyanov 
Signed-off-by: Alexey Dobriyan 
Cc: Sukadev Bhattiprolu 
Cc: Oleg Nesterov 
Cc: Paul Menage 
Cc: "Eric W. Biederman" 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

pid namespaces: round up the API

2007-10-19T18:53:37+00:00

The set of functions process_session, task_session, process_group and
task_pgrp is confusing, as the names can be mixed with each other when looking
at the code for a long time.

The proposals are to
* equip the functions that return the integer with _nr suffix to
  represent that fact,
* and to make all functions work with task (not process) by making
  the common prefix of the same name.

For monotony the routines signal_session() and set_signal_session() are
replaced with task_session_nr() and set_task_session(), especially since they
are only used with the explicit task->signal dereference.

Signed-off-by: Pavel Emelianov 
Acked-by: Serge E. Hallyn 
Cc: Kirill Korotaev 
Cc: "Eric W. Biederman" 
Cc: Cedric Le Goater 
Cc: Herbert Poetzl 
Cc: Sukadev Bhattiprolu 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

sched: fix guest time accounting going faster than user time accounting

2007-10-19T18:52:40+00:00

cputime_add already adds, dont do it twice.

Signed-off-by: Christian Borntraeger 
Signed-off-by: Ingo Molnar