linux-stable.git/include/linux/pid.h, branch linux-2.6.24.y

Uninline find_pid etc set of functions

2007-10-19T18:53:41+00:00

The find_pid/_vpid/_pid_ns functions are used to find the struct pid by its
id, depending on whic id - global or virtual - is used.

The find_vpid() is a macro that pushes the current->nsproxy->pid_ns on the
stack to call another function - find_pid_ns().  It turned out, that this
dereference together with the push itself cause the kernel text size to
grow too much.

Move all these out-of-line.  Together with the previous patch this saves a
bit less that 400 bytes from .text section.

Signed-off-by: Pavel Emelyanov 
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: remove the struct pid unneeded fields

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

Since we've switched from using pid->nr to pid->upids->nr some
fields on struct pid are no longer needed

Signed-off-by: Pavel Emelyanov 
Cc: Oleg Nesterov 
Cc: Sukadev Bhattiprolu 
Cc: Paul Menage 
Cc: "Eric W. Biederman" 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

pid namespaces: destroy pid namespace on init's death

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

Terminate all processes in a namespace when the reaper of the namespace is
exiting.  We do this by walking the pidmap of the namespace and sending
SIGKILL to all processes.

Signed-off-by: Sukadev Bhattiprolu 
Acked-by: Pavel Emelyanov 
Cc: Oleg Nesterov 
Cc: Sukadev Bhattiprolu 
Cc: Paul Menage 
Cc: "Eric W. Biederman" 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

pid namespaces: helpers to find the task by its numerical ids

2007-10-19T18:53:39+00:00

When searching the task by numerical id on may need to find it using global
pid (as it is done now in kernel) or by its virtual id, e.g.  when sending a
signal to a task from one namespace the sender will specify the task's virtual
id and we should find the task by this value.

[akpm@linux-foundation.org: fix gfs2 linkage]
Signed-off-by: Pavel Emelyanov 
Cc: Oleg Nesterov 
Cc: Sukadev Bhattiprolu 
Cc: Paul Menage 
Cc: "Eric W. Biederman" 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

pid namespaces: helpers to obtain pid numbers

2007-10-19T18:53:39+00:00

When showing pid to user or getting the pid numerical id for in-kernel use the
value of this id may differ depending on the namespace.

This set of helpers is used to get the global pid nr, the virtual (i.e.  seen
by task in its namespace) nr and the nr as it is seen from the specified
namespace.

Signed-off-by: Pavel Emelyanov 
Cc: Oleg Nesterov 
Cc: Sukadev Bhattiprolu 
Cc: Paul Menage 
Cc: "Eric W. Biederman" 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

pid namespaces: make alloc_pid(), free_pid() and put_pid() work with struct upid

2007-10-19T18:53:39+00:00

Each struct upid element of struct pid has to be initialized properly, i.e.
its nr mst be allocated from appropriate pidmap and ns set to appropriate
namespace.

When allocating a new pid, we need to know the namespace this pid will live
in, so the additional argument is added to alloc_pid().

On the other hand, the rest of the kernel still uses the pid->nr and
pid->pid_chain fields, so these ones are still initialized, but this will be
removed soon.

Signed-off-by: Pavel Emelyanov 
Cc: Oleg Nesterov 
Cc: Sukadev Bhattiprolu 
Cc: Paul Menage 
Cc: "Eric W. Biederman" 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

pid namespaces: introduce struct upid

2007-10-19T18:53:38+00:00

Since task will be visible from different pid namespaces each of them have to
be addressed by multiple pids.  struct upid is to store the information about
which id refers to which namespace.

The constuciton looks like this.  Each struct pid carried the reference
counter and the list of tasks attached to this pid.  At its end it has a
variable length array of struct upid-s.  Each struct upid has a numerical id
(pid itself), pointer to the namespace, this ID is valid in and is hashed into
a pid_hash for searching the pids.

The nr and pid_chain fields are kept in struct pid for a while to make kernel
still work (no patch initialize the upids yet), but it will be removed at the
end of this series when we switch to upids completely.

Signed-off-by: Sukadev Bhattiprolu 
Signed-off-by: Pavel Emelyanov 
Cc: Oleg Nesterov 
Cc: Paul Menage 
Cc: "Eric W. Biederman" 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

statically initialize struct pid for swapper

2007-05-11T15:29:35+00:00

Statically initialize a struct pid for the swapper process (pid_t == 0) and
attach it to init_task.  This is needed so task_pid(), task_pgrp() and
task_session() interfaces work on the swapper process also.

Signed-off-by: Sukadev Bhattiprolu 
Cc: Cedric Le Goater 
Cc: Dave Hansen 
Cc: Serge Hallyn 
Cc: Eric Biederman 
Cc: Herbert Poetzl 
Cc: 
Acked-by: Eric W. Biederman 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

attach_pid() with struct pid parameter

2007-05-11T15:29:35+00:00

attach_pid() currently takes a pid_t and then uses find_pid() to find the
corresponding struct pid.  Sometimes we already have the struct pid.  We can
then skip find_pid() if attach_pid() were to take a struct pid parameter.

Signed-off-by: Sukadev Bhattiprolu 
Cc: Cedric Le Goater 
Cc: Dave Hansen 
Cc: Serge Hallyn 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] pid: remove now unused do_each_task_pid and while_each_task_pid

2007-02-12T17:48:32+00:00

Now that I have changed all of the users remove the old version of these
functions.  This should be a clear hint to any out of tree users that they
should use do_each_pid_task and while_each_pid_task for new code.

Signed-off-by: Eric W. Biederman 
Cc: Alan Cox 
Cc: Oleg Nesterov 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds