Skip to content

R
raspberrypi-kernel

openeuler / raspberrypi-kernel

通知 13
Star 1
Fork 0
R
raspberrypi-kernel
切换分支/标签
  1. 20 10月, 2007 2 次提交
    • S
      pid namespaces: define and use task_active_pid_ns() wrapper · 2894d650
      由 Sukadev Bhattiprolu 提交于 
      With multiple pid namespaces, a process is known by some pid_t in every
ancestor pid namespace.  Every time the process forks, the child process also
gets a pid_t in every ancestor pid namespace.

While a process is visible in >=1 pid namespaces, it can see pid_t's in only
one pid namespace.  We call this pid namespace it's "active pid namespace",
and it is always the youngest pid namespace in which the process is known.

This patch defines and uses a wrapper to find the active pid namespace of a
process.  The implementation of the wrapper will be changed in when support
for multiple pid namespaces are added.

Changelog:
	2.6.22-rc4-mm2-pidns1:
	- [Pavel Emelianov, Alexey Dobriyan] Back out the change to use
	  task_active_pid_ns() in child_reaper() since task->nsproxy
	  can be NULL during task exit (so child_reaper() continues to
	  use init_pid_ns).

	  to implement child_reaper() since init_pid_ns.child_reaper to
	  implement child_reaper() since tsk->nsproxy can be NULL during exit.

	2.6.21-rc6-mm1:
	- Rename task_pid_ns() to task_active_pid_ns() to reflect that a
	  process can have multiple pid namespaces.
Signed-off-by: NSukadev Bhattiprolu <sukadev@us.ibm.com>
Acked-by: NPavel Emelianov <xemul@openvz.org>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Serge Hallyn <serue@us.ibm.com>
Cc: Herbert Poetzel <herbert@13thfloor.at>
Cc: Kirill Korotaev <dev@sw.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      2894d650
    • P
      pid namespaces: dynamic kmem cache allocator for pid namespaces · baf8f0f8
      由 Pavel Emelianov 提交于 
      Add kmem_cache to pid_namespace to allocate pids from.

Since both implementations expand the struct pid to carry more numerical
values each namespace should have separate cache to store pids of different
sizes.

Each kmem cache is name "pid_<NR>", where <NR> is the number of numerical ids
on the pid.  Different namespaces with same level of nesting will have same
caches.

This patch has two FIXMEs that are to be fixed after we reach the consensus
about the struct pid itself.

The first one is that the namespace to free the pid from in free_pid() must be
taken from pid.  Now the init_pid_ns is used.

The second FIXME is about the cache allocation.  When we do know how long the
object will be then we'll have to calculate this size in create_pid_cachep.
Right now the sizeof(struct pid) value is used.

[akpm@linux-foundation.org: coding-style repair]
Signed-off-by: NPavel Emelianov <xemul@openvz.org>
Acked-by: NCedric Le Goater <clg@fr.ibm.com>
Acked-by: NSukadev Bhattiprolu <sukadev@us.ibm.com>
Cc: Kirill Korotaev <dev@openvz.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Herbert Poetzl <herbert@13thfloor.at>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      baf8f0f8
  3. 17 7月, 2007 1 次提交
  5. 11 5月, 2007 2 次提交
  7. 09 5月, 2007 1 次提交
    • B
      Merge sys_clone()/sys_unshare() nsproxy and namespace handling · e3222c4e
      由 Badari Pulavarty 提交于 
      sys_clone() and sys_unshare() both makes copies of nsproxy and its associated
namespaces.  But they have different code paths.

This patch merges all the nsproxy and its associated namespace copy/clone
handling (as much as possible).  Posted on container list earlier for
feedback.

- Create a new nsproxy and its associated namespaces and pass it back to
  caller to attach it to right process.

- Changed all copy_*_ns() routines to return a new copy of namespace
  instead of attaching it to task->nsproxy.

- Moved the CAP_SYS_ADMIN checks out of copy_*_ns() routines.

- Removed unnessary !ns checks from copy_*_ns() and added BUG_ON()
  just incase.

- Get rid of all individual unshare_*_ns() routines and make use of
  copy_*_ns() instead.

[akpm@osdl.org: cleanups, warning fix]
[clg@fr.ibm.com: remove dup_namespaces() declaration]
[serue@us.ibm.com: fix CONFIG_IPC_NS=n, clone(CLONE_NEWIPC) retval]
[akpm@linux-foundation.org: fix build with CONFIG_SYSVIPC=n]
Signed-off-by: NBadari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: NSerge Hallyn <serue@us.ibm.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: <containers@lists.osdl.org>
Signed-off-by: NCedric Le Goater <clg@fr.ibm.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      e3222c4e
  9. 08 5月, 2007 1 次提交
  11. 31 1月, 2007 1 次提交
  13. 09 12月, 2006 4 次提交
  15. 08 12月, 2006 1 次提交
  17. 02 10月, 2006 8 次提交
  19. 27 9月, 2006 2 次提交
  21. 04 7月, 2006 1 次提交
  23. 01 4月, 2006 1 次提交
    • E
      [PATCH] pidhash: Refactor the pid hash table · 92476d7f
      由 Eric W. Biederman 提交于 
      Simplifies the code, reduces the need for 4 pid hash tables, and makes the
code more capable.

In the discussions I had with Oleg it was felt that to a large extent the
cleanup itself justified the work.  With struct pid being dynamically
allocated meant we could create the hash table entry when the pid was
allocated and free the hash table entry when the pid was freed.  Instead of
playing with the hash lists when ever a process would attach or detach to a
process.

For myself the fact that it gave what my previous task_ref patch gave for free
with simpler code was a big win.  The problem is that if you hold a reference
to struct task_struct you lock in 10K of low memory.  If you do that in a user
controllable way like /proc does, with an unprivileged but hostile user space
application with typical resource limits of 1000 fds and 100 processes I can
trigger the OOM killer by consuming all of low memory with task structs, on a
machine wight 1GB of low memory.

If I instead hold a reference to struct pid which holds a pointer to my
task_struct, I don't suffer from that problem because struct pid is 2 orders
of magnitude smaller.  In fact struct pid is small enough that most other
kernel data structures dwarf it, so simply limiting the number of referring
data structures is enough to prevent exhaustion of low memory.

This splits the current struct pid into two structures, struct pid and struct
pid_link, and reduces our number of hash tables from PIDTYPE_MAX to just one.
struct pid_link is the per process linkage into the hash tables and lives in
struct task_struct.  struct pid is given an indepedent lifetime, and holds
pointers to each of the pid types.

The independent life of struct pid simplifies attach_pid, and detach_pid,
because we are always manipulating the list of pids and not the hash table.
In addition in giving struct pid an indpendent life it makes the concept much
more powerful.

Kernel data structures can now embed a struct pid * instead of a pid_t and
not suffer from pid wrap around problems or from keeping unnecessarily
large amounts of memory allocated.
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      92476d7f
  25. 29 3月, 2006 2 次提交
    • O
      [PATCH] pidhash: don't count idle threads · 73b9ebfe
      由 Oleg Nesterov 提交于 
      fork_idle() does unhash_process() just after copy_process().  Contrary,
boot_cpu's idle thread explicitely registers itself for each pid_type with nr
= 0.

copy_process() already checks p->pid != 0 before process_counts++, I think we
can just skip attach_pid() calls and job control inits for idle threads and
kill unhash_process().  We don't need to cleanup ->proc_dentry in fork_idle()
because with this patch idle threads are never hashed in
kernel/pid.c:pid_hash[].

We don't need to hash pid == 0 in pidmap_init().  free_pidmap() is never
called with pid == 0 arg, so it will never be reused.  So it is still possible
to use pid == 0 in any PIDTYPE_xxx namespace from kernel/pid.c's POV.

However with this patch we don't hash pid == 0 for PIDTYPE_PID case.  We still
have have PIDTYPE_PGID/PIDTYPE_SID entries with pid == 0: /sbin/init and
kernel threads which don't call daemonize().
Signed-off-by: NOleg Nesterov <oleg@tv-sign.ru>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      73b9ebfe
    • E
      [PATCH] pidhash: kill switch_exec_pids · d73d6529
      由 Eric W. Biederman 提交于 
      switch_exec_pids is only called from de_thread by way of exec, and it is
only called when we are exec'ing from a non thread group leader.

Currently switch_exec_pids gives the leader the pid of the thread and
unhashes and rehashes all of the process groups.  The leader is already in
the EXIT_DEAD state so no one cares about it's pids.  The only concern for
the leader is that __unhash_process called from release_task will function
correctly.  If we don't touch the leader at all we know that
__unhash_process will work fine so there is no need to touch the leader.

For the task becomming the thread group leader, we just need to give it the
pid of the old thread group leader, add it to the task list, and attach it
to the session and the process group of the thread group.

Currently de_thread is also adding the task to the task list which is just
silly.

Currently the only leader of __detach_pid besides detach_pid is
switch_exec_pids because of the ugly extra work that was being
performed.

So this patch removes switch_exec_pids because it is doing too much, it is
creating an unnecessary special case in pid.c, duing work duplicated in
de_thread, and generally obscuring what it is going on.

The necessary work is added to de_thread, and it seems to be a little
clearer there what is going on.
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Kirill Korotaev <dev@sw.ru>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      d73d6529
  27. 09 1月, 2006 1 次提交
  29. 17 4月, 2005 1 次提交
    • L
      Linux-2.6.12-rc2 · 1da177e4
      由 Linus Torvalds 提交于 
      Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
      1da177e4