linux-toradex.git/kernel/pid.c, branch v2.6.25-rc2

kernel: remove fastcall in kernel/*

2008-02-08T17:22:31+00:00

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Harvey Harrison 
Acked-by: Ingo Molnar 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

pid: Extend/Fix pid_vnr

2008-02-08T17:22:27+00:00

pid_vnr returns the user space pid with respect to the pid namespace the
struct pid was allocated in.  What we want before we return a pid to user
space is the user space pid with respect to the pid namespace of current.

pid_vnr is a very nice optimization but because it isn't quite what we want
it is easy to use pid_vnr at times when we aren't certain the struct pid
was allocated in our pid namespace.

Currently this describes at least tiocgpgrp and tiocgsid in ttyio.c the
parent process reported in the core dumps and the parent process in
get_signal_to_deliver.

So unless the performance impact is huge having an interface that does what
we want instead of always what we want should be much more reliable and
much less error prone.

Signed-off-by: Eric W. Biederman 
Cc: Oleg Nesterov 
Acked-by: Pavel Emelyanov 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

namespaces: cleanup the code managed with PID_NS option

2008-02-08T17:22:23+00:00

Just like with the user namespaces, move the namespace management code into
the separate .c file and mark the (already existing) PID_NS option as "depend
on NAMESPACES"

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Pavel Emelyanov 
Acked-by: Serge Hallyn 
Cc: Cedric Le Goater 
Cc: "Eric W. Biederman" 
Cc: Herbert Poetzl 
Cc: Kirill Korotaev 
Cc: Sukadev Bhattiprolu 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

gfs2: make gfs2_glock.gl_owner_pid be a struct pid *

2008-02-07T16:42:06+00:00

The gl_owner_pid field is used to get the lock owning task by its pid, so make
it in a proper manner, i.e.  by using the struct pid pointer and pid_task()
function.

The pid_task() becomes exported for the gfs2 module.

Signed-off-by: Pavel Emelyanov 
Cc: "Eric W. Biederman" 
Acked-by: Steven Whitehouse 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

pidns: Place under CONFIG_EXPERIMENTAL

2007-11-15T02:45:43+00:00

This is my trivial patch to swat innumerable little bugs with a single
blow.

After some intensive review (my apologies for not having gotten to this
sooner) what we have looks like a good base to build on with the current
pid namespace code but it is not complete, and it is still much to simple
to find issues where the kernel does the wrong thing outside of the initial
pid namespace.

Until the dust settles and we are certain we have the ABI and the
implementation is as correct as humanly possible let's keep process ID
namespaces behind CONFIG_EXPERIMENTAL.

Allowing us the option of fixing any ABI or other bugs we find as long as
they are minor.

Allowing users of the kernel to avoid those bugs simply by ensuring their
kernel does not have support for multiple pid namespaces.

[akpm@linux-foundation.org: coding-style cleanups]
Signed-off-by: Eric W. Biederman 
Cc: Cedric Le Goater 
Cc: Adrian Bunk 
Cc: Jeremy Fitzhardinge 
Cc: Kir Kolyshkin 
Cc: Kirill Korotaev 
Cc: Pavel Emelyanov 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Uninline the task_xid_nr_ns() calls

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

Since these are expanded into call to pid_nr_ns() anyway, it's OK to move
the whole routine out-of-line.  This is a cheap way to save ~100 bytes from
vmlinux.  Together with the previous two patches, it saves half-a-kilo from
the vmlinux.

Un-inline other (currently inlined) functions must be done with additional
performance testing.

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

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

Uninline find_task_by_xxx set of functions

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

The find_task_by_something is a set of macros are used to find task by pid
depending on what kind of pid is proposed - global or virtual one.  All of
them are wrappers above the most generic one - find_task_by_pid_type_ns() -
and just substitute some args for it.

It turned out, that dereferencing the current->nsproxy->pid_ns construction
and pushing one more argument on the stack inline cause kernel text size to
grow.

This patch moves all this stuff out-of-line into kernel/pid.c.  Together
with the next patch it saves a bit less than 400 bytes from the .text
section.

Signed-off-by: Pavel Emelyanov 
Cc: Sukadev Bhattiprolu 
Cc: Oleg Nesterov 
Cc: Paul Menage 
Cc: "Eric W. Biederman" 
Acked-by: Ingo Molnar 
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