Commit Graph

4524 Commits

Author SHA1 Message Date
KOSAKI Motohiro 71cbb949d1 cgroup: list_for_each cleanup
--------------------------
while() {
	list_entry();
	...
}
--------------------------

is equivalent to following code.

--------------------------
list_for_each_entry(){
	...
}
--------------------------

later can review easily more.

this patch is just clean up.
it doesn't have any behavor change.

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Paul Menage <menage@google.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25 10:53:35 -07:00
Li Zefan 7e9abd89cb cgroup: use read lock to guard find_existing_css_set()
The function does not modify anything (except the temporary css template), so
it's sufficient to hold read lock.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Paul Menage <menage@google.com>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25 10:53:35 -07:00
Abhishek Sagar 8b6dd98682 kprobes: remove redundant config check
I noticed that there's a CONFIG_KPROBES check inside kernel/kprobes.c,
which is redundant.

Signed-off-by: Abhishek Sagar <sagar.abhishek@gmail.com>
Acked-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25 10:53:30 -07:00
Srinivasa D S ef53d9c5e4 kprobes: improve kretprobe scalability with hashed locking
Currently list of kretprobe instances are stored in kretprobe object (as
used_instances,free_instances) and in kretprobe hash table.  We have one
global kretprobe lock to serialise the access to these lists.  This causes
only one kretprobe handler to execute at a time.  Hence affects system
performance, particularly on SMP systems and when return probe is set on
lot of functions (like on all systemcalls).

Solution proposed here gives fine-grain locks that performs better on SMP
system compared to present kretprobe implementation.

Solution:

 1) Instead of having one global lock to protect kretprobe instances
    present in kretprobe object and kretprobe hash table.  We will have
    two locks, one lock for protecting kretprobe hash table and another
    lock for kretporbe object.

 2) We hold lock present in kretprobe object while we modify kretprobe
    instance in kretprobe object and we hold per-hash-list lock while
    modifying kretprobe instances present in that hash list.  To prevent
    deadlock, we never grab a per-hash-list lock while holding a kretprobe
    lock.

 3) We can remove used_instances from struct kretprobe, as we can
    track used instances of kretprobe instances using kretprobe hash
    table.

Time duration for kernel compilation ("make -j 8") on a 8-way ppc64 system
with return probes set on all systemcalls looks like this.

cacheline              non-cacheline             Un-patched kernel
aligned patch 	       aligned patch
===============================================================================
real    9m46.784s       9m54.412s                  10m2.450s
user    40m5.715s       40m7.142s                  40m4.273s
sys     2m57.754s       2m58.583s                  3m17.430s
===========================================================

Time duration for kernel compilation ("make -j 8) on the same system, when
kernel is not probed.
=========================
real    9m26.389s
user    40m8.775s
sys     2m7.283s
=========================

Signed-off-by: Srinivasa DS <srinivasa@in.ibm.com>
Signed-off-by: Jim Keniston <jkenisto@us.ibm.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25 10:53:30 -07:00
Dave Young 717115e1a5 printk ratelimiting rewrite
All ratelimit user use same jiffies and burst params, so some messages
(callbacks) will be lost.

For example:
a call printk_ratelimit(5 * HZ, 1)
b call printk_ratelimit(5 * HZ, 1) before the 5*HZ timeout of a, then b will
will be supressed.

- rewrite __ratelimit, and use a ratelimit_state as parameter.  Thanks for
  hints from andrew.

- Add WARN_ON_RATELIMIT, update rcupreempt.h

- remove __printk_ratelimit

- use __ratelimit in net_ratelimit

Signed-off-by: Dave Young <hidave.darkstar@gmail.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: "Paul E. McKenney" <paulmck@us.ibm.com>
Cc: Dave Young <hidave.darkstar@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25 10:53:29 -07:00
Arjan van de Ven 7a2c477069 kernel/irq/manage.c: replace a printk + WARN_ON() to a WARN()
Replace a printk+WARN_ON() by a WARN(); this increases the chance of the
string making it into the bugreport (ie: it goes inside the
---[ cut here ]--- section)

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25 10:53:29 -07:00
Arjan van de Ven a8f18b909c Add a WARN() macro; this is WARN_ON() + printk arguments
Add a WARN() macro that acts like WARN_ON(), with the added feature that it
takes a printk like argument that is printed as part of the warning message.

[akpm@linux-foundation.org: fix printk arguments]
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Cc: Greg KH <greg@kroah.com>
Cc: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25 10:53:29 -07:00
FUJITA Tomonori b69c49b784 clean up duplicated alloc/free_thread_info
We duplicate alloc/free_thread_info defines on many platforms (the
majority uses __get_free_pages/free_pages).  This patch defines common
defines and removes these duplicated defines.
__HAVE_ARCH_THREAD_INFO_ALLOCATOR is introduced for platforms that do
something different.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25 10:53:28 -07:00
KOSAKI Motohiro ac331d158e call_usermodehelper(): increase reliability
Presently call_usermodehelper_setup() uses GFP_ATOMIC.  but it can return
NULL _very_ easily.

GFP_ATOMIC is needed only when we can't sleep.  and, GFP_KERNEL is robust
and better.

thus, I add gfp_mask argument to call_usermodehelper_setup().

So, its callers pass the gfp_t as below:

call_usermodehelper() and call_usermodehelper_keys():
	depend on 'wait' argument.
call_usermodehelper_pipe():
	always GFP_KERNEL because always run under process context.
orderly_poweroff():
	pass to GFP_ATOMIC because may run under interrupt context.

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: "Paul Menage" <menage@google.com>
Reviewed-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25 10:53:28 -07:00
Adrian Bunk b03f6489f9 build kernel/profile.o only when requested
Build kernel/profile.o only if CONFIG_PROFILING is enabled.

This makes CONFIG_PROFILING=n kernels smaller.

As a bonus, some profile_tick() calls and one branch from schedule() are
now eliminated with CONFIG_PROFILING=n (but I doubt these are
measurable effects).

This patch changes the effects of CONFIG_PROFILING=n, but I don't think
having more than two choices would be the better choice.

This patch also adds the name of the first parameter to the prototypes
of profile_{hits,tick}() since I anyway had to add them for the dummy
functions.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25 10:53:27 -07:00
Vegard Nossum 2fc9c4e18f kallsyms: fix potential overflow in binary search
This will probably never trigger... but it won't hurt to be careful.

http://googleresearch.blogspot.com/2006/06/extra-extra-read-all-about-it-nearly.html

Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
Cc: Joshua Bloch <jjb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25 10:53:27 -07:00
Wang Chen 5df439ef06 flag parameters: fix compile error of sys_epoll_create1
GEN     .version
  CHK     include/linux/compile.h
  UPD     include/linux/compile.h
  CC      init/version.o
  LD      init/built-in.o
  LD      vmlinux
arch/x86/kernel/built-in.o: In function `sys_call_table':
(.rodata+0x8a4): undefined reference to `sys_epoll_create1'
make: *** [vmlinux] Error 1

Signed-off-by: Wang Chen <wangchen@cn.fujitsu.com>
Cc: Ulrich Drepper <drepper@redhat.com>
Cc: Davide Libenzi <davidel@xmailserver.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25 10:53:26 -07:00
Linus Torvalds ecc8b655b3 Merge branch 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  nohz: adjust tick_nohz_stop_sched_tick() call of s390 as well
  nohz: prevent tick stop outside of the idle loop
2008-07-24 12:55:01 -07:00
Linus Torvalds 2528ce3237 Merge branch 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  arch/mips/kernel/stacktrace.c: Heiko can't type
  kthread: reduce stack pressure in create_kthread and kthreadd
  fix core/stacktrace changes on avr32, mips, sh
2008-07-24 12:54:26 -07:00
Linus Torvalds 8ffa5b6596 Merge branch 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  sched: clean up compiler warning
  sched: fix hrtick & generic-ipi dependency
2008-07-24 12:53:51 -07:00
Ulrich Drepper be61a86d72 flag parameters: NONBLOCK in pipe
This patch adds O_NONBLOCK support to pipe2.  It is minimally more involved
than the patches for eventfd et.al but still trivial.  The interfaces of the
create_write_pipe and create_read_pipe helper functions were changed and the
one other caller as well.

The following test must be adjusted for architectures other than x86 and
x86-64 and in case the syscall numbers changed.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
#include <fcntl.h>
#include <stdio.h>
#include <unistd.h>
#include <sys/syscall.h>

#ifndef __NR_pipe2
# ifdef __x86_64__
#  define __NR_pipe2 293
# elif defined __i386__
#  define __NR_pipe2 331
# else
#  error "need __NR_pipe2"
# endif
#endif

int
main (void)
{
  int fds[2];
  if (syscall (__NR_pipe2, fds, 0) == -1)
    {
      puts ("pipe2(0) failed");
      return 1;
    }
  for (int i = 0; i < 2; ++i)
    {
      int fl = fcntl (fds[i], F_GETFL);
      if (fl == -1)
        {
          puts ("fcntl failed");
          return 1;
        }
      if (fl & O_NONBLOCK)
        {
          printf ("pipe2(0) set non-blocking mode for fds[%d]\n", i);
          return 1;
        }
      close (fds[i]);
    }

  if (syscall (__NR_pipe2, fds, O_NONBLOCK) == -1)
    {
      puts ("pipe2(O_NONBLOCK) failed");
      return 1;
    }
  for (int i = 0; i < 2; ++i)
    {
      int fl = fcntl (fds[i], F_GETFL);
      if (fl == -1)
        {
          puts ("fcntl failed");
          return 1;
        }
      if ((fl & O_NONBLOCK) == 0)
        {
          printf ("pipe2(O_NONBLOCK) does not set non-blocking mode for fds[%d]\n", i);
          return 1;
        }
      close (fds[i]);
    }

  puts ("OK");

  return 0;
}
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Signed-off-by: Ulrich Drepper <drepper@redhat.com>
Acked-by: Davide Libenzi <davidel@xmailserver.org>
Cc: Michael Kerrisk <mtk.manpages@googlemail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-24 10:47:29 -07:00
Ulrich Drepper 4006553b06 flag parameters: inotify_init
This patch introduces the new syscall inotify_init1 (note: the 1 stands for
the one parameter the syscall takes, as opposed to no parameter before).  The
values accepted for this parameter are function-specific and defined in the
inotify.h header.  Here the values must match the O_* flags, though.  In this
patch CLOEXEC support is introduced.

The following test must be adjusted for architectures other than x86 and
x86-64 and in case the syscall numbers changed.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
#include <fcntl.h>
#include <stdio.h>
#include <unistd.h>
#include <sys/syscall.h>

#ifndef __NR_inotify_init1
# ifdef __x86_64__
#  define __NR_inotify_init1 294
# elif defined __i386__
#  define __NR_inotify_init1 332
# else
#  error "need __NR_inotify_init1"
# endif
#endif

#define IN_CLOEXEC O_CLOEXEC

int
main (void)
{
  int fd;
  fd = syscall (__NR_inotify_init1, 0);
  if (fd == -1)
    {
      puts ("inotify_init1(0) failed");
      return 1;
    }
  int coe = fcntl (fd, F_GETFD);
  if (coe == -1)
    {
      puts ("fcntl failed");
      return 1;
    }
  if (coe & FD_CLOEXEC)
    {
      puts ("inotify_init1(0) set close-on-exit");
      return 1;
    }
  close (fd);

  fd = syscall (__NR_inotify_init1, IN_CLOEXEC);
  if (fd == -1)
    {
      puts ("inotify_init1(IN_CLOEXEC) failed");
      return 1;
    }
  coe = fcntl (fd, F_GETFD);
  if (coe == -1)
    {
      puts ("fcntl failed");
      return 1;
    }
  if ((coe & FD_CLOEXEC) == 0)
    {
      puts ("inotify_init1(O_CLOEXEC) does not set close-on-exit");
      return 1;
    }
  close (fd);

  puts ("OK");

  return 0;
}
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

[akpm@linux-foundation.org: add sys_ni stub]
Signed-off-by: Ulrich Drepper <drepper@redhat.com>
Acked-by: Davide Libenzi <davidel@xmailserver.org>
Cc: Michael Kerrisk <mtk.manpages@googlemail.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-24 10:47:28 -07:00
Ulrich Drepper b087498eb5 flag parameters: eventfd
This patch adds the new eventfd2 syscall.  It extends the old eventfd
syscall by one parameter which is meant to hold a flag value.  In this
patch the only flag support is EFD_CLOEXEC which causes the close-on-exec
flag for the returned file descriptor to be set.

A new name EFD_CLOEXEC is introduced which in this implementation must
have the same value as O_CLOEXEC.

The following test must be adjusted for architectures other than x86 and
x86-64 and in case the syscall numbers changed.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
#include <fcntl.h>
#include <stdio.h>
#include <unistd.h>
#include <sys/syscall.h>

#ifndef __NR_eventfd2
# ifdef __x86_64__
#  define __NR_eventfd2 290
# elif defined __i386__
#  define __NR_eventfd2 328
# else
#  error "need __NR_eventfd2"
# endif
#endif

#define EFD_CLOEXEC O_CLOEXEC

int
main (void)
{
  int fd = syscall (__NR_eventfd2, 1, 0);
  if (fd == -1)
    {
      puts ("eventfd2(0) failed");
      return 1;
    }
  int coe = fcntl (fd, F_GETFD);
  if (coe == -1)
    {
      puts ("fcntl failed");
      return 1;
    }
  if (coe & FD_CLOEXEC)
    {
      puts ("eventfd2(0) sets close-on-exec flag");
      return 1;
    }
  close (fd);

  fd = syscall (__NR_eventfd2, 1, EFD_CLOEXEC);
  if (fd == -1)
    {
      puts ("eventfd2(EFD_CLOEXEC) failed");
      return 1;
    }
  coe = fcntl (fd, F_GETFD);
  if (coe == -1)
    {
      puts ("fcntl failed");
      return 1;
    }
  if ((coe & FD_CLOEXEC) == 0)
    {
      puts ("eventfd2(EFD_CLOEXEC) does not set close-on-exec flag");
      return 1;
    }
  close (fd);

  puts ("OK");

  return 0;
}
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

[akpm@linux-foundation.org: add sys_ni stub]
Signed-off-by: Ulrich Drepper <drepper@redhat.com>
Acked-by: Davide Libenzi <davidel@xmailserver.org>
Cc: Michael Kerrisk <mtk.manpages@googlemail.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-24 10:47:27 -07:00
Ulrich Drepper 9deb27baed flag parameters: signalfd
This patch adds the new signalfd4 syscall.  It extends the old signalfd
syscall by one parameter which is meant to hold a flag value.  In this
patch the only flag support is SFD_CLOEXEC which causes the close-on-exec
flag for the returned file descriptor to be set.

A new name SFD_CLOEXEC is introduced which in this implementation must
have the same value as O_CLOEXEC.

The following test must be adjusted for architectures other than x86 and
x86-64 and in case the syscall numbers changed.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
#include <fcntl.h>
#include <signal.h>
#include <stdio.h>
#include <unistd.h>
#include <sys/syscall.h>

#ifndef __NR_signalfd4
# ifdef __x86_64__
#  define __NR_signalfd4 289
# elif defined __i386__
#  define __NR_signalfd4 327
# else
#  error "need __NR_signalfd4"
# endif
#endif

#define SFD_CLOEXEC O_CLOEXEC

int
main (void)
{
  sigset_t ss;
  sigemptyset (&ss);
  sigaddset (&ss, SIGUSR1);
  int fd = syscall (__NR_signalfd4, -1, &ss, 8, 0);
  if (fd == -1)
    {
      puts ("signalfd4(0) failed");
      return 1;
    }
  int coe = fcntl (fd, F_GETFD);
  if (coe == -1)
    {
      puts ("fcntl failed");
      return 1;
    }
  if (coe & FD_CLOEXEC)
    {
      puts ("signalfd4(0) set close-on-exec flag");
      return 1;
    }
  close (fd);

  fd = syscall (__NR_signalfd4, -1, &ss, 8, SFD_CLOEXEC);
  if (fd == -1)
    {
      puts ("signalfd4(SFD_CLOEXEC) failed");
      return 1;
    }
  coe = fcntl (fd, F_GETFD);
  if (coe == -1)
    {
      puts ("fcntl failed");
      return 1;
    }
  if ((coe & FD_CLOEXEC) == 0)
    {
      puts ("signalfd4(SFD_CLOEXEC) does not set close-on-exec flag");
      return 1;
    }
  close (fd);

  puts ("OK");

  return 0;
}
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

[akpm@linux-foundation.org: add sys_ni stub]
Signed-off-by: Ulrich Drepper <drepper@redhat.com>
Acked-by: Davide Libenzi <davidel@xmailserver.org>
Cc: Michael Kerrisk <mtk.manpages@googlemail.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-24 10:47:27 -07:00
Ulrich Drepper aaca0bdca5 flag parameters: paccept
This patch is by far the most complex in the series.  It adds a new syscall
paccept.  This syscall differs from accept in that it adds (at the userlevel)
two additional parameters:

- a signal mask
- a flags value

The flags parameter can be used to set flag like SOCK_CLOEXEC.  This is
imlpemented here as well.  Some people argued that this is a property which
should be inherited from the file desriptor for the server but this is against
POSIX.  Additionally, we really want the signal mask parameter as well
(similar to pselect, ppoll, etc).  So an interface change in inevitable.

The flag value is the same as for socket and socketpair.  I think diverging
here will only create confusion.  Similar to the filesystem interfaces where
the use of the O_* constants differs, it is acceptable here.

The signal mask is handled as for pselect etc.  The mask is temporarily
installed for the thread and removed before the call returns.  I modeled the
code after pselect.  If there is a problem it's likely also in pselect.

For architectures which use socketcall I maintained this interface instead of
adding a system call.  The symmetry shouldn't be broken.

The following test must be adjusted for architectures other than x86 and
x86-64 and in case the syscall numbers changed.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
#include <errno.h>
#include <fcntl.h>
#include <pthread.h>
#include <signal.h>
#include <stdio.h>
#include <unistd.h>
#include <netinet/in.h>
#include <sys/socket.h>
#include <sys/syscall.h>

#ifndef __NR_paccept
# ifdef __x86_64__
#  define __NR_paccept 288
# elif defined __i386__
#  define SYS_PACCEPT 18
#  define USE_SOCKETCALL 1
# else
#  error "need __NR_paccept"
# endif
#endif

#ifdef USE_SOCKETCALL
# define paccept(fd, addr, addrlen, mask, flags) \
  ({ long args[6] = { \
       (long) fd, (long) addr, (long) addrlen, (long) mask, 8, (long) flags }; \
     syscall (__NR_socketcall, SYS_PACCEPT, args); })
#else
# define paccept(fd, addr, addrlen, mask, flags) \
  syscall (__NR_paccept, fd, addr, addrlen, mask, 8, flags)
#endif

#define PORT 57392

#define SOCK_CLOEXEC O_CLOEXEC

static pthread_barrier_t b;

static void *
tf (void *arg)
{
  pthread_barrier_wait (&b);
  int s = socket (AF_INET, SOCK_STREAM, 0);
  struct sockaddr_in sin;
  sin.sin_family = AF_INET;
  sin.sin_addr.s_addr = htonl (INADDR_LOOPBACK);
  sin.sin_port = htons (PORT);
  connect (s, (const struct sockaddr *) &sin, sizeof (sin));
  close (s);

  pthread_barrier_wait (&b);
  s = socket (AF_INET, SOCK_STREAM, 0);
  sin.sin_port = htons (PORT);
  connect (s, (const struct sockaddr *) &sin, sizeof (sin));
  close (s);
  pthread_barrier_wait (&b);

  pthread_barrier_wait (&b);
  sleep (2);
  pthread_kill ((pthread_t) arg, SIGUSR1);

  return NULL;
}

static void
handler (int s)
{
}

int
main (void)
{
  pthread_barrier_init (&b, NULL, 2);

  struct sockaddr_in sin;
  pthread_t th;
  if (pthread_create (&th, NULL, tf, (void *) pthread_self ()) != 0)
    {
      puts ("pthread_create failed");
      return 1;
    }

  int s = socket (AF_INET, SOCK_STREAM, 0);
  int reuse = 1;
  setsockopt (s, SOL_SOCKET, SO_REUSEADDR, &reuse, sizeof (reuse));
  sin.sin_family = AF_INET;
  sin.sin_addr.s_addr = htonl (INADDR_LOOPBACK);
  sin.sin_port = htons (PORT);
  bind (s, (struct sockaddr *) &sin, sizeof (sin));
  listen (s, SOMAXCONN);

  pthread_barrier_wait (&b);

  int s2 = paccept (s, NULL, 0, NULL, 0);
  if (s2 < 0)
    {
      puts ("paccept(0) failed");
      return 1;
    }

  int coe = fcntl (s2, F_GETFD);
  if (coe & FD_CLOEXEC)
    {
      puts ("paccept(0) set close-on-exec-flag");
      return 1;
    }
  close (s2);

  pthread_barrier_wait (&b);

  s2 = paccept (s, NULL, 0, NULL, SOCK_CLOEXEC);
  if (s2 < 0)
    {
      puts ("paccept(SOCK_CLOEXEC) failed");
      return 1;
    }

  coe = fcntl (s2, F_GETFD);
  if ((coe & FD_CLOEXEC) == 0)
    {
      puts ("paccept(SOCK_CLOEXEC) does not set close-on-exec flag");
      return 1;
    }
  close (s2);

  pthread_barrier_wait (&b);

  struct sigaction sa;
  sa.sa_handler = handler;
  sa.sa_flags = 0;
  sigemptyset (&sa.sa_mask);
  sigaction (SIGUSR1, &sa, NULL);

  sigset_t ss;
  pthread_sigmask (SIG_SETMASK, NULL, &ss);
  sigaddset (&ss, SIGUSR1);
  pthread_sigmask (SIG_SETMASK, &ss, NULL);

  sigdelset (&ss, SIGUSR1);
  alarm (4);
  pthread_barrier_wait (&b);

  errno = 0 ;
  s2 = paccept (s, NULL, 0, &ss, 0);
  if (s2 != -1 || errno != EINTR)
    {
      puts ("paccept did not fail with EINTR");
      return 1;
    }

  close (s);

  puts ("OK");

  return 0;
}
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

[akpm@linux-foundation.org: make it compile]
[akpm@linux-foundation.org: add sys_ni stub]
Signed-off-by: Ulrich Drepper <drepper@redhat.com>
Acked-by: Davide Libenzi <davidel@xmailserver.org>
Cc: Michael Kerrisk <mtk.manpages@googlemail.com>
Cc: <linux-arch@vger.kernel.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Roland McGrath <roland@redhat.com>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-24 10:47:27 -07:00
Uwe Kleine-König 82736f4d1d generic irqs: handle failure of irqchip->set_type in setup_irq
set_type returns an int indicating success or failure, but up to now
setup_irq ignores that.

In my case this resulted in a machine hang:

gpio-keys requested IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING, but
arm/ns9xxx can only trigger on one direction so set_type didn't touch
the configuration which happens do default to a level sensitiveness and
returned -EINVAL.  setup_irq ignored that and unmasked the irq.  This
resulted in an endless triggering of the gpio-key interrupt service
routine which effectively killed the machine.

With this patch applied setup_irq propagates the error to the caller.

Note that before in the case

	chip && !chip->set_type && !chip->name

a NULL pointer was feed to printk.  This is fixed, too.

Signed-off-by: Uwe Kleine-König <Uwe.Kleine-Koenig@digi.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-24 10:47:24 -07:00
David Howells f0af566da6 pm: fix try_to_freeze_tasks()'s use of do_div()
Fix try_to_freeze_tasks()'s use of do_div() on an s64 by making
elapsed_csecs64 a u64 instead and dividing that.

Possibly this should be guarded lest the interval calculation turn up
negative, but the possible negativity of the result of the division is
cast away anyway.

This was introduced by patch 438e2ce68d.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: "Rafael J. Wysocki" <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-24 10:47:24 -07:00
Zhang Rui 2f15fc4bdf pm: schedule sysrq poweroff on boot cpu
schedule sysrq poweroff on boot cpu.

sysrq poweroff needs to disable nonboot cpus, and we need to run this on boot
cpu to avoid any recursion.  http://bugzilla.kernel.org/show_bug.cgi?id=10897

[kosaki.motohiro@jp.fujitsu.com: build fix]
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Tested-by: Rus <harbour@sfinx.od.ua>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-24 10:47:24 -07:00
Zhang Rui c1a220e7ac pm: introduce new interfaces schedule_work_on() and queue_work_on()
This interface allows adding a job on a specific cpu.

Although a work struct on a cpu will be scheduled to other cpu if the cpu
dies, there is a recursion if a work task tries to offline the cpu it's
running on.  we need to schedule the task to a specific cpu in this case.
http://bugzilla.kernel.org/show_bug.cgi?id=10897

[oleg@tv-sign.ru: cleanups]
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Tested-by: Rus <harbour@sfinx.od.ua>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-24 10:47:23 -07:00
Akinobu Mita 0d83304c7e pm: hibernation: simplify memory bitmap
This patch simplifies the memory bitmap manipulations.

- remove the member size in struct bm_block

It is not necessary for struct bm_block to have the number of bit chunks that
can be calculated by using end_pfn and start_pfn.

- use find_next_bit() for memory_bm_next_pfn

No need to invent the bitmap library only for the memory bitmap.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-24 10:47:23 -07:00
David Brownell 77437fd4e6 pm: boot time suspend selftest
Boot-time test for system suspend states (STR or standby).  The generic
RTC framework triggers wakeup alarms, which are used to exit those states.

  - Measures some aspects of suspend time ... this uses "jiffies" until
    someone converts it to use a timebase that works properly even while
    timer IRQs are disabled.

  - Triggered by a command line parameter.  By default nothing even
    vaguely troublesome will happen, but "test_suspend=mem" will give
    you a brief STR test during system boot.  (Or you may need to use
    "test_suspend=standby" instead, if your hardware needs that.)

This isn't without problems.  It fires early enough during boot that for
example both PCMCIA and MMC stacks have misbehaved.  The workaround in
those cases was to boot without such media cards inserted.

[matthltc@us.ibm.com: fix compile failure in boot time suspend selftest]
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Pavel Machek <pavel@suse.cz>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Signed-off-by: Matt Helsley <matthltc@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-24 10:47:22 -07:00
Pavel Machek 0d63081d41 swsusp: provide users with a hint about the no_console_suspend option
Tell the user about the no_console_suspend option, so that we don't have to
tell each bug reporter personally.

[akpm@linux-foundation.org: clarify the text a little]
Signed-off-by: Pavel Machek <pavel@suse.cz>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-24 10:47:22 -07:00
Andrew G. Morgan ab763c7112 security: filesystem capabilities refactor kernel code
To date, we've tried hard to confine filesystem support for capabilities
to the security modules.  This has left a lot of the code in
kernel/capability.c in a state where it looks like it supports something
that filesystem support for capabilities actually suppresses when the LSM
security/commmoncap.c code runs.  What is left is a lot of code that uses
sub-optimal locking in the main kernel

With this change we refactor the main kernel code and make it explicit
which locks are needed and that the only remaining kernel races in this
area are associated with non-filesystem capability code.

Signed-off-by: Andrew G. Morgan <morgan@kernel.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-24 10:47:22 -07:00
Andi Kleen e5ff215941 hugetlb: multiple hstates for multiple page sizes
Add basic support for more than one hstate in hugetlbfs.  This is the key
to supporting multiple hugetlbfs page sizes at once.

- Rather than a single hstate, we now have an array, with an iterator
- default_hstate continues to be the struct hstate which we use by default
- Add functions for architectures to register new hstates

[akpm@linux-foundation.org: coding-style fixes]
Acked-by: Adam Litke <agl@us.ibm.com>
Acked-by: Nishanth Aravamudan <nacc@us.ibm.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-24 10:47:17 -07:00
Mel Gorman a1e78772d7 hugetlb: reserve huge pages for reliable MAP_PRIVATE hugetlbfs mappings until fork()
This patch reserves huge pages at mmap() time for MAP_PRIVATE mappings in
a similar manner to the reservations taken for MAP_SHARED mappings.  The
reserve count is accounted both globally and on a per-VMA basis for
private mappings.  This guarantees that a process that successfully calls
mmap() will successfully fault all pages in the future unless fork() is
called.

The characteristics of private mappings of hugetlbfs files behaviour after
this patch are;

1. The process calling mmap() is guaranteed to succeed all future faults until
   it forks().
2. On fork(), the parent may die due to SIGKILL on writes to the private
   mapping if enough pages are not available for the COW. For reasonably
   reliable behaviour in the face of a small huge page pool, children of
   hugepage-aware processes should not reference the mappings; such as
   might occur when fork()ing to exec().
3. On fork(), the child VMAs inherit no reserves. Reads on pages already
   faulted by the parent will succeed. Successful writes will depend on enough
   huge pages being free in the pool.
4. Quotas of the hugetlbfs mount are checked at reserve time for the mapper
   and at fault time otherwise.

Before this patch, all reads or writes in the child potentially needs page
allocations that can later lead to the death of the parent.  This applies
to reads and writes of uninstantiated pages as well as COW.  After the
patch it is only a write to an instantiated page that causes problems.

Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Acked-by: Adam Litke <agl@us.ibm.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Cc: William Lee Irwin III <wli@holomorphy.com>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-24 10:47:16 -07:00
Adrian Bunk c748e1340e mm/vmstat.c: proper externs
This patch adds proper extern declarations for five variables in
include/linux/vmstat.h

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-24 10:47:14 -07:00
Peter Zijlstra 58838cf3ca sched: clean up compiler warning
Reported-by: Daniel Walker <dwalker@mvista.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-24 13:24:57 +02:00
Ingo Molnar 1986b0cb16 ftrace: remove latency-tracer leftover
remove the :vim=ft=help tag from trace files.

I used them years ago to syntax-highlight traces and forgot about this hack.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-24 08:10:02 +02:00
Ingo Molnar 28afe961a1 Merge branch 'linus' into tracing/urgent 2008-07-24 08:09:26 +02:00
Linus Torvalds 338b9bb3ad Merge branch 'x86/auditsc' of git://git.kernel.org/pub/scm/linux/kernel/git/frob/linux-2.6-roland
* 'x86/auditsc' of git://git.kernel.org/pub/scm/linux/kernel/git/frob/linux-2.6-roland:
  i386 syscall audit fast-path
  x86_64 ia32 syscall audit fast-path
  x86_64 syscall audit fast-path
  x86_64: remove bogus optimization in sysret_signal
2008-07-23 20:39:21 -07:00
Linus Torvalds 7f9dce3837 Merge branch 'sched/for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'sched/for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  sched: hrtick_enabled() should use cpu_active()
  sched, x86: clean up hrtick implementation
  sched: fix build error, provide partition_sched_domains() unconditionally
  sched: fix warning in inc_rt_tasks() to not declare variable 'rq' if it's not needed
  cpu hotplug: Make cpu_active_map synchronization dependency clear
  cpu hotplug, sched: Introduce cpu_active_map and redo sched domain managment (take 2)
  sched: rework of "prioritize non-migratable tasks over migratable ones"
  sched: reduce stack size in isolated_cpu_setup()
  Revert parts of "ftrace: do not trace scheduler functions"

Fixed up conflicts in include/asm-x86/thread_info.h (due to the
TIF_SINGLESTEP unification vs TIF_HRTICK_RESCHED removal) and
kernel/sched_fair.c (due to cpu_active_map vs for_each_cpu_mask_nr()
introduction).
2008-07-23 19:36:53 -07:00
Linus Torvalds 26dcce0fab Merge branch 'cpus4096-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'cpus4096-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (31 commits)
  NR_CPUS: Replace NR_CPUS in speedstep-centrino.c
  cpumask: Provide a generic set of CPUMASK_ALLOC macros, FIXUP
  NR_CPUS: Replace NR_CPUS in cpufreq userspace routines
  NR_CPUS: Replace per_cpu(..., smp_processor_id()) with __get_cpu_var
  NR_CPUS: Replace NR_CPUS in arch/x86/kernel/genapic_flat_64.c
  NR_CPUS: Replace NR_CPUS in arch/x86/kernel/genx2apic_uv_x.c
  NR_CPUS: Replace NR_CPUS in arch/x86/kernel/cpu/proc.c
  NR_CPUS: Replace NR_CPUS in arch/x86/kernel/cpu/mcheck/mce_64.c
  cpumask: Optimize cpumask_of_cpu in lib/smp_processor_id.c, fix
  cpumask: Use optimized CPUMASK_ALLOC macros in the centrino_target
  cpumask: Provide a generic set of CPUMASK_ALLOC macros
  cpumask: Optimize cpumask_of_cpu in lib/smp_processor_id.c
  cpumask: Optimize cpumask_of_cpu in kernel/time/tick-common.c
  cpumask: Optimize cpumask_of_cpu in drivers/misc/sgi-xp/xpc_main.c
  cpumask: Optimize cpumask_of_cpu in arch/x86/kernel/ldt.c
  cpumask: Optimize cpumask_of_cpu in arch/x86/kernel/io_apic_64.c
  cpumask: Replace cpumask_of_cpu with cpumask_of_cpu_ptr
  Revert "cpumask: introduce new APIs"
  cpumask: make for_each_cpu_mask a bit smaller
  net: Pass reference to cpumask variable in net/sunrpc/svc.c
  ...

Fix up trivial conflicts in drivers/cpufreq/cpufreq.c manually
2008-07-23 18:37:44 -07:00
Linus Torvalds d7b6de14a0 Merge branch 'core/softlockup-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core/softlockup-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  softlockup: fix invalid proc_handler for softlockup_panic
  softlockup: fix watchdog task wakeup frequency
  softlockup: fix watchdog task wakeup frequency
  softlockup: show irqtrace
  softlockup: print a module list on being stuck
  softlockup: fix NMI hangs due to lock race - 2.6.26-rc regression
  softlockup: fix false positives on nohz if CPU is 100% idle for more than 60 seconds
  softlockup: fix softlockup_thresh fix
  softlockup: fix softlockup_thresh unaligned access and disable detection at runtime
  softlockup: allow panic on lockup
2008-07-23 18:34:13 -07:00
Roland McGrath 86a1c34a92 x86_64 syscall audit fast-path
This adds a fast path for 64-bit syscall entry and exit when
TIF_SYSCALL_AUDIT is set, but no other kind of syscall tracing.
This path does not need to save and restore all registers as
the general case of tracing does.  Avoiding the iret return path
when syscall audit is enabled helps performance a lot.

Signed-off-by: Roland McGrath <roland@redhat.com>
2008-07-23 17:47:32 -07:00
Uwe Kleine-König 2db873211b set_irq_wake: fix return code and wake status tracking
Since 15a647eba9 set_irq_wake returned -ENXIO
if another device had it already enabled.  Zero is the right value to
return in this case.  Moreover the change to desc->status was not reverted
if desc->chip->set_wake returned an error.

Signed-off-by: Uwe Kleine-König <Uwe.Kleine-Koenig@digi.com>
Acked-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-23 09:35:53 -07:00
Ingo Molnar 422037bafd sched: fix hrtick & generic-ipi dependency
Andrew Morton reported this s390 allmodconfig build failure:

 kernel/built-in.o: In function `hrtick_start_fair':
 sched.c:(.text+0x69c6): undefined reference to `__smp_call_function_single'

the reason is that s390 is not a generic-ipi SMP platform yet, while
the hrtick code relies on it. Fix the dependency.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-23 11:18:28 +02:00
Linus Torvalds 6eaaaac974 Merge git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus
* git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus:
  remove CONFIG_KMOD from core kernel code
  remove CONFIG_KMOD from lib
  remove CONFIG_KMOD from sparc64
  rework try_then_request_module to do less in non-modular kernels
  remove mention of CONFIG_KMOD from documentation
  make CONFIG_KMOD invisible
  modules: Take a shortcut for checking if an address is in a module
  module: turn longs into ints for module sizes
  Shrink struct module: CONFIG_UNUSED_SYMBOLS ifdefs
  module: reorder struct module to save space on 64 bit builds
  module: generic each_symbol iterator function
  module: don't use stop_machine for waiting rmmod
2008-07-22 13:17:15 -07:00
Linus Torvalds 53baaaa968 Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6: (79 commits)
  arm: bus_id -> dev_name() and dev_set_name() conversions
  sparc64: fix up bus_id changes in sparc core code
  3c59x: handle pci_name() being const
  MTD: handle pci_name() being const
  HP iLO driver
  sysdev: Convert the x86 mce tolerant sysdev attribute to generic attribute
  sysdev: Add utility functions for simple int/ulong variable sysdev attributes
  sysdev: Pass the attribute to the low level sysdev show/store function
  driver core: Suppress sysfs warnings for device_rename().
  kobject: Transmit return value of call_usermodehelper() to caller
  sysfs-rules.txt: reword API stability statement
  debugfs: Implement debugfs_remove_recursive()
  HOWTO: change email addresses of James in HOWTO
  always enable FW_LOADER unless EMBEDDED=y
  uio-howto.tmpl: use unique output names
  uio-howto.tmpl: use standard copyright/legal markings
  sysfs: don't call notify_change
  sysdev: fix debugging statements in registration code.
  kobject: should use kobject_put() in kset-example
  kobject: reorder kobject to save space on 64 bit builds
  ...
2008-07-22 13:13:47 -07:00
Atsushi Nemoto 5f17156fc5 Fix build on COMPAT platforms when CONFIG_EPOLL is disabled
Add missing cond_syscall() entry for compat_sys_epoll_pwait.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Cc: Davide Libenzi <davidel@xmailserver.org>
Cc: <stable@kernel.org>		[2.6.25.x, 2.6.26.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-22 09:59:41 -07:00
Miao Xie 91cd4d6ef0 cpusets: fix wrong domain attr updates
Fix wrong domain attr updates, or we will always update the first sched
domain attr.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Cc: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: Paul Jackson <pj@sgi.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: <stable@kernel.org>	[2.6.26.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-22 09:59:41 -07:00
Johannes Berg a1ef5adb4c remove CONFIG_KMOD from core kernel code
Always compile request_module when the kernel allows modules.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-07-22 19:24:31 +10:00
Rusty Russell 3a642e99ba modules: Take a shortcut for checking if an address is in a module
This patch keeps track of the boundaries of module allocation, in
order to speed up module_text_address().

Inspired by Arjan's version, which required arch-specific defines:

	Various pieces of the kernel (lockdep, latencytop, etc) tend
	to store backtraces, sometimes at a relatively high
	frequency. In itself this isn't a big performance deal (after
	all you're using diagnostics features), but there have been
	some complaints from people who have over 100 modules loaded
	that this is a tad too slow.

	This is due to the new backtracer code which looks at every
	slot on the stack to see if it's a kernel/module text address,
	so that's 1024 slots.  1024 times 100 modules... that's a lot
	of list walking.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-07-22 19:24:28 +10:00
Denys Vlasenko 2f0f2a334b module: turn longs into ints for module sizes
This shrinks module.o and each *.ko file.

And finally, structure members which hold length of module
code (four such members there) and count of symbols
are converted from longs to ints.

We cannot possibly have a module where 32 bits won't
be enough to hold such counts.

For one, module loading checks module size for sanity
before loading, so such insanely big module will fail
that test first.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-07-22 19:24:27 +10:00
Denys Vlasenko f7f5b67557 Shrink struct module: CONFIG_UNUSED_SYMBOLS ifdefs
module.c and module.h conatains code for finding
exported symbols which are declared with EXPORT_UNUSED_SYMBOL,
and this code is compiled in even if CONFIG_UNUSED_SYMBOLS is not set
and thus there can be no EXPORT_UNUSED_SYMBOLs in modules anyway
(because EXPORT_UNUSED_SYMBOL(x) are compiled out to nothing then).

This patch adds required #ifdefs.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-07-22 19:24:27 +10:00
Rusty Russell dafd0940c9 module: generic each_symbol iterator function
Introduce an each_symbol() iterator to avoid duplicating the knowledge
about the 5 different sections containing symbols.  Currently only
used by find_symbol(), but will be used by symbol_put_addr() too.

(Includes NULL ptr deref fix by Jiri Kosina <jkosina@suse.cz>)

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jiri Kosina <jkosina@suse.cz>
2008-07-22 19:24:26 +10:00
Rusty Russell da39ba5e1d module: don't use stop_machine for waiting rmmod
rmmod has a little-used "-w" option, meaning that instead of failing if the
module is in use, it should block until the module becomes unused.

In this case, we don't need to use stop_machine: Max Krasnyansky
indicated that would be useful for SystemTap which loads/unloads new
modules frequently.

Cc: Max Krasnyansky <maxk@qualcomm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-07-22 19:24:25 +10:00
Andi Kleen 4a0b2b4dbe sysdev: Pass the attribute to the low level sysdev show/store function
This allow to dynamically generate attributes and share show/store
functions between attributes. Right now most attributes are generated
by special macros and lots of duplicated code. With the attribute
passed it's instead possible to attach some data to the attribute
and then use that in shared low level functions to do different things.

I need this for the dynamically generated bank attributes in the x86
machine check code, but it'll allow some further cleanups.

I converted all users in tree to the new show/store prototype. It's a single
huge patch to avoid unbisectable sections.

Runtime tested: x86-32, x86-64
Compiled only: ia64, powerpc
Not compile tested/only grep converted: sh, arm, avr32

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-07-21 21:55:02 -07:00
Ingo Molnar ba42059fbd sched: hrtick_enabled() should use cpu_active()
Peter pointed out that hrtick_enabled() should use cpu_active().

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-20 11:02:06 +02:00
Ingo Molnar d986434a7d Merge branch 'sched/urgent' into sched/devel 2008-07-20 11:01:29 +02:00
Peter Zijlstra 31656519e1 sched, x86: clean up hrtick implementation
random uvesafb failures were reported against Gentoo:

  http://bugs.gentoo.org/show_bug.cgi?id=222799

and Mihai Moldovan bisected it back to:

> 8f4d37ec07 is first bad commit
> commit 8f4d37ec07
> Author: Peter Zijlstra <a.p.zijlstra@chello.nl>
> Date:   Fri Jan 25 21:08:29 2008 +0100
>
>    sched: high-res preemption tick

Linus suspected it to be hrtick + vm86 interaction and observed:

> Btw, Peter, Ingo: I think that commit is doing bad things. They aren't
> _incorrect_ per se, but they are definitely bad.
>
> Why?
>
> Using random _TIF_WORK_MASK flags is really impolite for doing
> "scheduling" work. There's a reason that arch/x86/kernel/entry_32.S
> special-cases the _TIF_NEED_RESCHED flag: we don't want to exit out of
> vm86 mode unnecessarily.
>
> See the "work_notifysig_v86" label, and how it does that
> "save_v86_state()" thing etc etc.

Right, I never liked having to fiddle with those TIF flags. Initially I
needed it because the hrtimer base lock could not nest in the rq lock.
That however is fixed these days.

Currently the only reason left to fiddle with the TIF flags is remote
wakeups. We cannot program a remote cpu's hrtimer. I've been thinking
about using the new and improved IPI function call stuff to implement
hrtimer_start_on().

However that does require that smp_call_function_single(.wait=0) works
from interrupt context - /me looks at the latest series from Jens - Yes
that does seem to be supported, good.

Here's a stab at cleaning this stuff up ...

Mihai reported test success as well.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Tested-by: Mihai Moldovan <ionic@ionic.de>
Cc: Michal Januszewski <spock@gentoo.org>
Cc: Antonino Daplas <adaplas@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-20 10:37:28 +02:00
Mike Travis c18a41fbbc cpumask: Optimize cpumask_of_cpu in kernel/time/tick-common.c
* Optimize various places where a pointer to the cpumask_of_cpu value
    will result in reducing stack pressure.

Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-18 22:02:59 +02:00
Mike Travis 65c0118453 cpumask: Replace cpumask_of_cpu with cpumask_of_cpu_ptr
* This patch replaces the dangerous lvalue version of cpumask_of_cpu
    with new cpumask_of_cpu_ptr macros.  These are patterned after the
    node_to_cpumask_ptr macros.

    In general terms, if there is a cpumask_of_cpu_map[] then a pointer to
    the cpumask_of_cpu_map[cpu] entry is used.  The cpumask_of_cpu_map
    is provided when there is a large NR_CPUS count, reducing
    greatly the amount of code generated and stack space used for
    cpumask_of_cpu().  The pointer to the cpumask_t value is needed for
    calling set_cpus_allowed_ptr() to reduce the amount of stack space
    needed to pass the cpumask_t value.

    If there isn't a cpumask_of_cpu_map[], then a temporary variable is
    declared and filled in with value from cpumask_of_cpu(cpu) as well as
    a pointer variable pointing to this temporary variable.  Afterwards,
    the pointer is used to reference the cpumask value.  The compiler
    will optimize out the extra dereference through the pointer as well
    as the stack space used for the pointer, resulting in identical code.

    A good example of the orthogonal usages is in net/sunrpc/svc.c:

	case SVC_POOL_PERCPU:
	{
		unsigned int cpu = m->pool_to[pidx];
		cpumask_of_cpu_ptr(cpumask, cpu);

		*oldmask = current->cpus_allowed;
		set_cpus_allowed_ptr(current, cpumask);
		return 1;
	}
	case SVC_POOL_PERNODE:
	{
		unsigned int node = m->pool_to[pidx];
		node_to_cpumask_ptr(nodecpumask, node);

		*oldmask = current->cpus_allowed;
		set_cpus_allowed_ptr(current, nodecpumask);
		return 1;
	}

Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-18 22:02:57 +02:00
Ingo Molnar bb2c018b09 Merge branch 'linus' into cpus4096
Conflicts:

	drivers/acpi/processor_throttling.c

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-18 22:00:54 +02:00
Ingo Molnar 9b610fda0d Merge branch 'linus' into timers/nohz 2008-07-18 19:53:16 +02:00
Steven Rostedt 1e01cb0c6f ftrace: only trace preempt off with preempt tracer
When PREEMPT_TRACER and IRQSOFF_TRACER are both configured and irqsoff
tracer is running, the preempt_off sections might also be traced.

Thanks to Andrew Morton for pointing out my mistake of spin_lock disabling
interrupts while he was reviewing ftrace.txt. Seems that my example I used
actually hit this bug.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-18 18:57:34 +02:00
Mike Travis 8df185a95c kthread: reduce stack pressure in create_kthread and kthreadd
* Replace:

  	set_cpus_allowed(..., CPU_MASK_ALL)

    with:

  	set_cpus_allowed_ptr(..., CPU_MASK_ALL_PTR)

    to remove excessive stack requirements when NR_CPUS=4096.

Signed-off-by: Mike Travis <travis@sgi.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-18 18:46:58 +02:00
Hiroshi Shimamoto 4dca10a960 softlockup: fix invalid proc_handler for softlockup_panic
The type of softlockup_panic is int, but the proc_handler is
proc_doulongvec_minmax(). This handler is for unsigned long.

This handler should be proc_dointvec_minmax().

Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-18 18:29:28 +02:00
Thomas Gleixner b8f8c3cf0a nohz: prevent tick stop outside of the idle loop
Jack Ren and Eric Miao tracked down the following long standing
problem in the NOHZ code:

	scheduler switch to idle task
	enable interrupts

Window starts here

	----> interrupt happens (does not set NEED_RESCHED)
	      	irq_exit() stops the tick

	----> interrupt happens (does set NEED_RESCHED)

	return from schedule()
	
	cpu_idle(): preempt_disable();

Window ends here

The interrupts can happen at any point inside the race window. The
first interrupt stops the tick, the second one causes the scheduler to
rerun and switch away from idle again and we end up with the tick
disabled.

The fact that it needs two interrupts where the first one does not set
NEED_RESCHED and the second one does made the bug obscure and extremly
hard to reproduce and analyse. Kudos to Jack and Eric.

Solution: Limit the NOHZ functionality to the idle loop to make sure
that we can not run into such a situation ever again.

cpu_idle()
{
	preempt_disable();

	while(1) {
		 tick_nohz_stop_sched_tick(1); <- tell NOHZ code that we
		 			          are in the idle loop

		 while (!need_resched())
		       halt();

		 tick_nohz_restart_sched_tick(); <- disables NOHZ mode
		 preempt_enable_no_resched();
		 schedule();
		 preempt_disable();
	}
}

In hindsight we should have done this forever, but ... 

/me grabs a large brown paperbag.

Debugged-by: Jack Ren <jack.ren@marvell.com>, 
Debugged-by: eric miao <eric.y.miao@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-07-18 18:10:28 +02:00
David Howells 577b4a58d2 sched: fix warning in inc_rt_tasks() to not declare variable 'rq' if it's not needed
Fix inc_rt_tasks() to not declare variable 'rq' if it's not needed.  It is
declared if CONFIG_SMP or CONFIG_RT_GROUP_SCHED, but only used if CONFIG_SMP.

This is a consequence of patch 1f11eb6a8b plus
patch 1100ac91b6.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-18 13:56:03 +02:00
Steven Rostedt e59494f441 ftrace: fix 4d3702b6 (post-v2.6.26): WARNING: at kernel/lockdep.c:2731 check_flags (ftrace)
On Wed, 16 Jul 2008, Vegard Nossum wrote:

> When booting 4d3702b6, I got this huge thing:
>
> Testing tracer wakeup: <4>------------[ cut here ]------------
> WARNING: at kernel/lockdep.c:2731 check_flags+0x123/0x160()
> Modules linked in:
> Pid: 1, comm: swapper Not tainted 2.6.26-crashing-02127-g4d3702b6 #30
>  [<c015c349>] warn_on_slowpath+0x59/0xb0
>  [<c01276c6>] ? ftrace_call+0x5/0x8
>  [<c012d800>] ? native_read_tsc+0x0/0x20
>  [<c0158de2>] ? sub_preempt_count+0x12/0xf0
>  [<c01814eb>] ? trace_hardirqs_off+0xb/0x10
>  [<c0182fbc>] ? __lock_acquire+0x2cc/0x1120
>  [<c01814eb>] ? trace_hardirqs_off+0xb/0x10
>  [<c01276af>] ? mcount_call+0x5/0xa
>  [<c017ff53>] check_flags+0x123/0x160
>  [<c0183e61>] lock_acquire+0x51/0xd0
>  [<c01276c6>] ? ftrace_call+0x5/0x8
>  [<c0613d4f>] _spin_lock_irqsave+0x5f/0xa0
>  [<c01a8d45>] ? ftrace_record_ip+0xf5/0x220
>  [<c02d5413>] ? debug_locks_off+0x3/0x50
>  [<c01a8d45>] ftrace_record_ip+0xf5/0x220
>  [<c01276af>] mcount_call+0x5/0xa
>  [<c02d5418>] ? debug_locks_off+0x8/0x50
>  [<c017ff27>] check_flags+0xf7/0x160
>  [<c0183e61>] lock_acquire+0x51/0xd0
>  [<c01276c6>] ? ftrace_call+0x5/0x8
>  [<c0613d4f>] _spin_lock_irqsave+0x5f/0xa0
>  [<c01affcd>] ? wakeup_tracer_call+0x6d/0xf0
>  [<c01625e2>] ? _local_bh_enable+0x62/0xb0
>  [<c0158ddd>] ? sub_preempt_count+0xd/0xf0
>  [<c01affcd>] wakeup_tracer_call+0x6d/0xf0
>  [<c0162724>] ? __do_softirq+0xf4/0x110
>  [<c01afff1>] ? wakeup_tracer_call+0x91/0xf0
>  [<c01276c6>] ftrace_call+0x5/0x8
>  [<c0162724>] ? __do_softirq+0xf4/0x110
>  [<c0158de2>] ? sub_preempt_count+0x12/0xf0
>  [<c01625e2>] _local_bh_enable+0x62/0xb0
>  [<c0162724>] __do_softirq+0xf4/0x110
>  [<c01627ed>] do_softirq+0xad/0xb0
>  [<c0162a15>] irq_exit+0xa5/0xb0
>  [<c013a506>] smp_apic_timer_interrupt+0x66/0xa0
>  [<c02d3fac>] ? trace_hardirqs_off_thunk+0xc/0x10
>  [<c0127449>] apic_timer_interrupt+0x2d/0x34
>  [<c018007b>] ? find_usage_backwards+0xb/0xf0
>  [<c0613a09>] ? _spin_unlock_irqrestore+0x69/0x80
>  [<c014ef32>] tg_shares_up+0x132/0x1d0
>  [<c014d2a2>] walk_tg_tree+0x62/0xa0
>  [<c014ee00>] ? tg_shares_up+0x0/0x1d0
>  [<c014a860>] ? tg_nop+0x0/0x10
>  [<c015499d>] update_shares+0x5d/0x80
>  [<c0154a2f>] try_to_wake_up+0x6f/0x280
>  [<c01a8b90>] ? __ftrace_modify_code+0x0/0xc0
>  [<c01a8b90>] ? __ftrace_modify_code+0x0/0xc0
>  [<c0154c94>] wake_up_process+0x14/0x20
>  [<c01725f6>] kthread_create+0x66/0xb0
>  [<c0195400>] ? do_stop+0x0/0x200
>  [<c0195320>] ? __stop_machine_run+0x30/0xb0
>  [<c0195340>] __stop_machine_run+0x50/0xb0
>  [<c0195400>] ? do_stop+0x0/0x200
>  [<c01a8b90>] ? __ftrace_modify_code+0x0/0xc0
>  [<c061242d>] ? mutex_unlock+0xd/0x10
>  [<c01953cc>] stop_machine_run+0x2c/0x60
>  [<c01a94d3>] unregister_ftrace_function+0x103/0x180
>  [<c01b0517>] stop_wakeup_tracer+0x17/0x60
>  [<c01b056f>] wakeup_tracer_ctrl_update+0xf/0x30
>  [<c01ab8d5>] trace_selftest_startup_wakeup+0xb5/0x130
>  [<c01ab950>] ? trace_wakeup_test_thread+0x0/0x70
>  [<c01aadf5>] register_tracer+0x135/0x1b0
>  [<c0877d02>] init_wakeup_tracer+0xd/0xf
>  [<c085d437>] kernel_init+0x1a9/0x2ce
>  [<c061397b>] ? _spin_unlock_irq+0x3b/0x60
>  [<c02d3f9c>] ? trace_hardirqs_on_thunk+0xc/0x10
>  [<c0877cf5>] ? init_wakeup_tracer+0x0/0xf
>  [<c0182646>] ? trace_hardirqs_on_caller+0x126/0x180
>  [<c02d3f9c>] ? trace_hardirqs_on_thunk+0xc/0x10
>  [<c01269c8>] ? restore_nocheck_notrace+0x0/0xe
>  [<c085d28e>] ? kernel_init+0x0/0x2ce
>  [<c085d28e>] ? kernel_init+0x0/0x2ce
>  [<c01275fb>] kernel_thread_helper+0x7/0x10
>  =======================
> ---[ end trace a7919e7f17c0a725 ]---
> irq event stamp: 579530
> hardirqs last  enabled at (579528): [<c01826ab>] trace_hardirqs_on+0xb/0x10
> hardirqs last disabled at (579529): [<c01814eb>] trace_hardirqs_off+0xb/0x10
> softirqs last  enabled at (579530): [<c0162724>] __do_softirq+0xf4/0x110
> softirqs last disabled at (579517): [<c01627ed>] do_softirq+0xad/0xb0
> irq event stamp: 579530
> hardirqs last  enabled at (579528): [<c01826ab>] trace_hardirqs_on+0xb/0x10
> hardirqs last disabled at (579529): [<c01814eb>] trace_hardirqs_off+0xb/0x10
> softirqs last  enabled at (579530): [<c0162724>] __do_softirq+0xf4/0x110
> softirqs last disabled at (579517): [<c01627ed>] do_softirq+0xad/0xb0
> PASSED
>
> Incidentally, the kernel also hung while I was typing in this report.

Things get weird between lockdep and ftrace because ftrace can be called
within lockdep internal code (via the mcount pointer) and lockdep can be
called with ftrace (via spin_locks).

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Tested-by: Vegard Nossum <vegard.nossum@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-18 13:47:15 +02:00
Max Krasnyansky 39b0fad712 cpu hotplug: Make cpu_active_map synchronization dependency clear
This goes on top of the cpu_active_map (take 2) patch.

Currently we depend on the stop_machine to provide nescessesary
synchronization for the cpu_active_map updates.
As Dmitry Adamushko pointed this is fragile and is not much clearer
than the previous scheme. In other words we do not want to depend on
the internal stop machine operation here.
So make the synchronization rules clear by doing synchronize_sched()
after clearing out cpu active bit.

Tested on quad-Core2 with:

   while true; do
      for i in 1 2 3; do
        echo 0 > /sys/devices/system/cpu/cpu$i/online
      done
      for i in 1 2 3; do
        echo 1 > /sys/devices/system/cpu/cpu$i/online
      done
   done
and
   stress -c 200

No lockdep, preempt or other complaints.

Signed-off-by: Max Krasnyansky <maxk@qualcomm.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-18 13:23:18 +02:00
Max Krasnyansky e761b77252 cpu hotplug, sched: Introduce cpu_active_map and redo sched domain managment (take 2)
This is based on Linus' idea of creating cpu_active_map that prevents
scheduler load balancer from migrating tasks to the cpu that is going
down.

It allows us to simplify domain management code and avoid unecessary
domain rebuilds during cpu hotplug event handling.

Please ignore the cpusets part for now. It needs some more work in order
to avoid crazy lock nesting. Although I did simplfy and unify domain
reinitialization logic. We now simply call partition_sched_domains() in
all the cases. This means that we're using exact same code paths as in
cpusets case and hence the test below cover cpusets too.
Cpuset changes to make rebuild_sched_domains() callable from various
contexts are in the separate patch (right next after this one).

This not only boots but also easily handles
	while true; do make clean; make -j 8; done
and
	while true; do on-off-cpu 1; done
at the same time.
(on-off-cpu 1 simple does echo 0/1 > /sys/.../cpu1/online thing).

Suprisingly the box (dual-core Core2) is quite usable. In fact I'm typing
this on right now in gnome-terminal and things are moving just fine.

Also this is running with most of the debug features enabled (lockdep,
mutex, etc) no BUG_ONs or lockdep complaints so far.

I believe I addressed all of the Dmitry's comments for original Linus'
version. I changed both fair and rt balancer to mask out non-active cpus.
And replaced cpu_is_offline() with !cpu_active() in the main scheduler
code where it made sense (to me).

Signed-off-by: Max Krasnyanskiy <maxk@qualcomm.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Gregory Haskins <ghaskins@novell.com>
Cc: dmitry.adamushko@gmail.com
Cc: pj@sgi.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-18 13:22:25 +02:00
Dmitry Adamushko 7ebefa8cee sched: rework of "prioritize non-migratable tasks over migratable ones"
(1) handle in a generic way all cases when a newly woken-up task is
not migratable (not just a corner case when "rt_se->nr_cpus_allowed ==
1")

(2) if current is to be preempted, then make sure "p" will be picked
up by pick_next_task_rt().
i.e. move task's group at the head of its list as well.

currently, it's not a case for the group-scheduling case as described
here: http://www.ussg.iu.edu/hypermail/linux/kernel/0807.0/0134.html

Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Gregory Haskins <ghaskins@novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-18 12:55:14 +02:00
Mike Travis 13b40c1e40 sched: reduce stack size in isolated_cpu_setup()
* Remove 16k stack requirements in isolated_cpu_setup when NR_CPUS=4096.

Signed-off-by: Mike Travis <travis@sgi.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-18 11:55:42 +02:00
Ingo Molnar d88c169197 Revert parts of "ftrace: do not trace scheduler functions"
the removal of -mno-spe in the !ftrace case was not intended.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-18 08:59:24 +02:00
Ingo Molnar 393d81aa02 Merge branch 'linus' into xen-64bit 2008-07-17 23:57:20 +02:00
Linus Torvalds bdec6cace4 Merge branch 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  ftrace: do not trace library functions
  ftrace: do not trace scheduler functions
  ftrace: fix lockup with MAXSMP
  ftrace: fix merge buglet
2008-07-17 10:37:10 -07:00
Jeremy Fitzhardinge 93a0886e23 x86, xen, power: fix up config dependencies on PM
Xen save/restore needs bits of code enabled by PM_SLEEP, and PM_SLEEP
depends on PM.  So make XEN_SAVE_RESTORE depend on PM and PM_SLEEP
depend on XEN_SAVE_RESTORE.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-17 19:25:20 +02:00
Ingo Molnar c349e0a01c ftrace: do not trace scheduler functions
do not trace scheduler functions - it's still a bit fragile
and can lock up with:

  http://redhat.com/~mingo/misc/config-Thu_Jul_17_13_34_52_CEST_2008

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-17 17:40:11 +02:00
Roland McGrath 666f164f4f fix dangling zombie when new parent ignores children
This fixes an arcane bug that we think was a regression introduced
by commit b2b2cbc4b2.  When a parent
ignores SIGCHLD (or uses SA_NOCLDWAIT), its children would self-reap
but they don't if it's using ptrace on them.  When the parent thread
later exits and ceases to ptrace a child but leaves other live
threads in the parent's thread group, any zombie children are left
dangling.  The fix makes them self-reap then, as they would have
done earlier if ptrace had not been in use.

Signed-off-by: Roland McGrath <roland@redhat.com>
2008-07-16 18:02:34 -07:00
Roland McGrath 14dd0b8141 do_wait: return security_task_wait() error code in place of -ECHILD
This reverts the effect of commit f2cc3eb133
"do_wait: fix security checks".  That change reverted the effect of commit
7324328446.  The rationale for the original
commit still stands.  The inconsistent treatment of children hidden by
ptrace was an unintended omission in the original change and in no way
invalidates its purpose.

This makes do_wait return the error returned by security_task_wait()
(usually -EACCES) in place of -ECHILD when there are some children the
caller would be able to wait for if not for the permission failure.  A
permission error will give the user a clue to look for security policy
problems, rather than for mysterious wait bugs.

Signed-off-by: Roland McGrath <roland@redhat.com>
2008-07-16 18:02:34 -07:00
Roland McGrath f470021adb ptrace children revamp
ptrace no longer fiddles with the children/sibling links, and the
old ptrace_children list is gone.  Now ptrace, whether of one's own
children or another's via PTRACE_ATTACH, just uses the new ptraced
list instead.

There should be no user-visible difference that matters.  The only
change is the order in which do_wait() sees multiple stopped
children and stopped ptrace attachees.  Since wait_task_stopped()
was changed earlier so it no longer reorders the children list, we
already know this won't cause any new problems.

Signed-off-by: Roland McGrath <roland@redhat.com>
2008-07-16 18:02:33 -07:00
Roland McGrath 98abed0200 do_wait reorganization
This breaks out the guts of do_wait into three subfunctions.
The control flow is less nonobvious without so much goto.
do_wait_thread and ptrace_do_wait contain the main work of the outer loop.
wait_consider_task contains the main work of the inner loop.

Signed-off-by: Roland McGrath <roland@redhat.com>
2008-07-16 18:02:33 -07:00
Linus Torvalds dc7c65db28 Merge branch 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6
* 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6: (72 commits)
  Revert "x86/PCI: ACPI based PCI gap calculation"
  PCI: remove unnecessary volatile in PCIe hotplug struct controller
  x86/PCI: ACPI based PCI gap calculation
  PCI: include linux/pm_wakeup.h for device_set_wakeup_capable
  PCI PM: Fix pci_prepare_to_sleep
  x86/PCI: Fix PCI config space for domains > 0
  Fix acpi_pm_device_sleep_wake() by providing a stub for CONFIG_PM_SLEEP=n
  PCI: Simplify PCI device PM code
  PCI PM: Introduce pci_prepare_to_sleep and pci_back_from_sleep
  PCI ACPI: Rework PCI handling of wake-up
  ACPI: Introduce new device wakeup flag 'prepared'
  ACPI: Introduce acpi_device_sleep_wake function
  PCI: rework pci_set_power_state function to call platform first
  PCI: Introduce platform_pci_power_manageable function
  ACPI: Introduce acpi_bus_power_manageable function
  PCI: make pci_name use dev_name
  PCI: handle pci_name() being const
  PCI: add stub for pci_set_consistent_dma_mask()
  PCI: remove unused arch pcibios_update_resource() functions
  PCI: fix pci_setup_device()'s sprinting into a const buffer
  ...

Fixed up conflicts in various files (arch/x86/kernel/setup_64.c,
arch/x86/pci/irq.c, arch/x86/pci/pci.h, drivers/acpi/sleep/main.c,
drivers/pci/pci.c, drivers/pci/pci.h, include/acpi/acpi_bus.h) from x86
and ACPI updates manually.
2008-07-16 17:25:46 -07:00
Rafael J. Wysocki 25f2f3daad snapshot: Use pm_mutex for mutual exclusion
We can avoid taking the BKL in snapshot_ioctl() if pm_mutex is used to prevent
the ioctls from being executed concurrently.

In addition, although it is only possible to open /dev/snapshot once, the task
which has done that may spawn a child that will inherit the open descriptor,
so in theory they can call snapshot_write(), snapshot_read() and
snapshot_release() concurrently.  pm_mutex can also be used for mutual
exclusion in such cases.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Len Brown <len.brown@intel.com>
2008-07-16 23:27:03 +02:00
Alan Cox 52d11025db snapshot: Push BKL down into ioctl handlers
Push BKL down into ioctl handlers - snapshot device.

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
2008-07-16 23:27:03 +02:00
Rafael J. Wysocki ebb12db51f Freezer: Introduce PF_FREEZER_NOSIG
The freezer currently attempts to distinguish kernel threads from
user space tasks by checking if their mm pointer is unset and it
does not send fake signals to kernel threads.  However, there are
kernel threads, mostly related to networking, that behave like
user space tasks and may want to be sent a fake signal to be frozen.

Introduce the new process flag PF_FREEZER_NOSIG that will be set
by default for all kernel threads and make the freezer only send
fake signals to the tasks having PF_FREEZER_NOSIG unset.  Provide
the set_freezable_with_signal() function to be called by the kernel
threads that want to be sent a fake signal for freezing.

This patch should not change the freezer's observable behavior.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Len Brown <len.brown@intel.com>
2008-07-16 23:27:03 +02:00
Zhang Rui b62b8ef906 force offline the processor during hot-removal
The ACPI device node for the cpu has already been unregistered
when acpi_processor_handle_eject is called.
Thus we should offline the cpu and continue, rather than a failure here.
http://bugzilla.kernel.org/show_bug.cgi?id=9772

Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
2008-07-16 23:27:01 +02:00
Ingo Molnar 6717ef1aa7 Revert "suspend, xen: enable PM_SLEEP for CONFIG_XEN"
This reverts commit 6fbbec428c8e7bb617da2e8a589af2e97bcf3bc4.

Rafael doesnt like it - it breaks various assumptions.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-16 11:07:16 +02:00
Jeremy Fitzhardinge 0775b3dbcb suspend, xen: enable PM_SLEEP for CONFIG_XEN
Xen save/restore requires PM_SLEEP to be set without requiring
SUSPEND or HIBERNATION.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stephen Tweedie <sct@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-16 11:04:27 +02:00
Ingo Molnar 82638844d9 Merge branch 'linus' into cpus4096
Conflicts:

	arch/x86/xen/smp.c
	kernel/sched_rt.c
	net/iucv/iucv.c

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-16 00:29:07 +02:00
Ingo Molnar 1e09481365 Merge branch 'linus' into core/softlockup
Conflicts:

	kernel/softlockup.c

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-15 23:12:58 +02:00
Jeremy Fitzhardinge 63cf13b77a generic ipi function calls: wait on alloc failure fallback
When a GFP_ATOMIC allocation fails, it falls back to allocating the
data on the stack and converting it to a waiting call.

Make sure we actually wait in this case.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-15 14:12:20 -07:00
Linus Torvalds 59190f4213 Merge branch 'generic-ipi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'generic-ipi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (22 commits)
  generic-ipi: more merge fallout
  generic-ipi: merge fix
  x86, visws: use mach-default/entry_arch.h
  x86, visws: fix generic-ipi build
  generic-ipi: fixlet
  generic-ipi: fix s390 build bug
  generic-ipi: fix linux-next tree build failure
  fix: "smp_call_function: get rid of the unused nonatomic/retry argument"
  fix: "smp_call_function: get rid of the unused nonatomic/retry argument"
  fix "smp_call_function: get rid of the unused nonatomic/retry argument"
  on_each_cpu(): kill unused 'retry' parameter
  smp_call_function: get rid of the unused nonatomic/retry argument
  sh: convert to generic helpers for IPI function calls
  parisc: convert to generic helpers for IPI function calls
  mips: convert to generic helpers for IPI function calls
  m32r: convert to generic helpers for IPI function calls
  arm: convert to generic helpers for IPI function calls
  alpha: convert to generic helpers for IPI function calls
  ia64: convert to generic helpers for IPI function calls
  powerpc: convert to generic helpers for IPI function calls
  ...

Fix trivial conflicts due to rcu updates in kernel/rcupdate.c manually
2008-07-15 14:12:03 -07:00
Ingo Molnar 1a781a777b Merge branch 'generic-ipi' into generic-ipi-for-linus
Conflicts:

	arch/powerpc/Kconfig
	arch/s390/kernel/time.c
	arch/x86/kernel/apic_32.c
	arch/x86/kernel/cpu/perfctr-watchdog.c
	arch/x86/kernel/i8259_64.c
	arch/x86/kernel/ldt.c
	arch/x86/kernel/nmi_64.c
	arch/x86/kernel/smpboot.c
	arch/x86/xen/smp.c
	include/asm-x86/hw_irq_32.h
	include/asm-x86/hw_irq_64.h
	include/asm-x86/mach-default/irq_vectors.h
	include/asm-x86/mach-voyager/irq_vectors.h
	include/asm-x86/smp.h
	kernel/Makefile

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-15 21:55:59 +02:00
Ingo Molnar 6c9fcaf2ee Merge branch 'core/rcu' into core/rcu-for-linus 2008-07-15 21:10:12 +02:00
Linus Torvalds da6e88f496 Merge branch 'timers/for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'timers/for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86: add PCI ID for 6300ESB force hpet
  x86: add another PCI ID for ICH6 force-hpet
  kernel-paramaters: document pmtmr= command line option
  acpi_pm clccksource: fix printk format warning
  nohz: don't stop idle tick if softirqs are pending.
  pmtmr: allow command line override of ioport
  nohz: reduce jiffies polling overhead
  hrtimer: Remove unused variables in ktime_divns()
  hrtimer: remove warning in hres_timers_resume
  posix-timers: print RT watchdog message
2008-07-15 10:39:57 -07:00
Linus Torvalds 61d97f4fcf Merge branch 'genirq' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'genirq' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  genirq: remove extraneous checks in manage.c
  genirq: Expose default irq affinity mask (take 3)
2008-07-15 10:39:22 -07:00
Linus Torvalds af5329cdf5 Merge branch 'core/stacktrace' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core/stacktrace' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  generic-ipi: powerpc/generic-ipi tree build failure
  stacktrace: fix build failure on sparc64
  stacktrace: export save_stack_trace[_tsk]
  stacktrace: fix modular build, export print_stack_trace and save_stack_trace
  backtrace: replace timer with tasklet + completions
  stacktrace: add saved stack traces to backtrace self-test
  stacktrace: print_stack_trace() cleanup
  debugging: make stacktrace independent from DEBUG_KERNEL
  stacktrace: don't crash on invalid stack trace structs
2008-07-15 10:31:35 -07:00
Linus Torvalds 85082fd7cb Merge branch 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm
* 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm: (241 commits)
  [ARM] 5171/1: ep93xx: fix compilation of modules using clocks
  [ARM] 5133/2: at91sam9g20 defconfig file
  [ARM] 5130/4: Support for the at91sam9g20
  [ARM] 5160/1: IOP3XX: gpio/gpiolib support
  [ARM] at91: Fix NAND FLASH timings for at91sam9x evaluation kits.
  [ARM] 5084/1: zylonite: Register AC97 device
  [ARM] 5085/2: PXA: Move AC97 over to the new central device declaration model
  [ARM] 5120/1: pxa: correct platform driver names for PXA25x and PXA27x UDC drivers
  [ARM] 5147/1: pxaficp_ir: drop pxa_gpio_mode calls, as pin setting
  [ARM] 5145/1: PXA2xx: provide api to control IrDA pins state
  [ARM] 5144/1: pxaficp_ir: cleanup includes
  [ARM] pxa: remove pxa_set_cken()
  [ARM] pxa: allow clk aliases
  [ARM] Feroceon: don't disable BPU on boot
  [ARM] Orion: LED support for HP mv2120
  [ARM] Orion: add RD88F5181L-FXO support
  [ARM] Orion: add RD88F5181L-GE support
  [ARM] Orion: add Netgear WNR854T support
  [ARM] s3c2410_defconfig: update for current build
  [ARM] Acer n30: Minor style and indentation fixes.
  ...
2008-07-14 16:06:58 -07:00
Linus Torvalds 666484f025 Merge branch 'core/softirq' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core/softirq' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  softirq: remove irqs_disabled warning from local_bh_enable
  softirq: remove initialization of static per-cpu variable
  Remove argument from open_softirq which is always NULL
2008-07-14 15:28:42 -07:00
Linus Torvalds 4bb0057f99 Merge branch 'core/printk' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core/printk' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, generic: mark early_printk as asmlinkage
  printk: export console_drivers
  printk: remember the message level for multi-line output
  printk: refactor processing of line severity tokens
  printk: don't prefer unsuited consoles on registration
  printk: clean up recursion check related static variables
  namespacecheck: more kernel/printk.c fixes
  namespacecheck: fix kernel printk.c
2008-07-14 15:27:43 -07:00
Linus Torvalds 40e7babbb5 Merge branch 'core/locking' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core/locking' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  lockdep: fix kernel/fork.c warning
  lockdep: fix ftrace irq tracing false positive
  lockdep: remove duplicate definition of STATIC_LOCKDEP_MAP_INIT
  lockdep: add lock_class information to lock_chain and output it
  lockdep: add lock_class information to lock_chain and output it
  lockdep: output lock_class key instead of address for forward dependency output
  __mutex_lock_common: use signal_pending_state()
  mutex-debug: check mutex magic before owner

Fixed up conflict in kernel/fork.c manually
2008-07-14 14:55:13 -07:00
Linus Torvalds 948769a5ba Merge branch 'sched/new-API-sched_setscheduler' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'sched/new-API-sched_setscheduler' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  sched: add new API sched_setscheduler_nocheck: add a flag to control access checks
2008-07-14 14:50:49 -07:00
Linus Torvalds e18425a0ab Merge branch 'tracing/for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'tracing/for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (228 commits)
  ftrace: build fix for ftraced_suspend
  ftrace: separate out the function enabled variable
  ftrace: add ftrace_kill_atomic
  ftrace: use current CPU for function startup
  ftrace: start wakeup tracing after setting function tracer
  ftrace: check proper config for preempt type
  ftrace: trace schedule
  ftrace: define function trace nop
  ftrace: move sched_switch enable after markers
  ftrace: prevent ftrace modifications while being kprobe'd, v2
  fix "ftrace: store mcount address in rec->ip"
  mmiotrace broken in linux-next (8-bit writes only)
  ftrace: avoid modifying kprobe'd records
  ftrace: freeze kprobe'd records
  kprobes: enable clean usage of get_kprobe
  ftrace: store mcount address in rec->ip
  ftrace: build fix with gcc 4.3
  namespacecheck: fixes
  ftrace: fix "notrace" filtering priority
  ftrace: fix printout
  ...
2008-07-14 14:49:54 -07:00
Linus Torvalds d1794f2c5b Merge branch 'bkl-removal' of git://git.lwn.net/linux-2.6
* 'bkl-removal' of git://git.lwn.net/linux-2.6: (146 commits)
  IB/umad: BKL is not needed for ib_umad_open()
  IB/uverbs: BKL is not needed for ib_uverbs_open()
  bf561-coreb: BKL unneeded for open()
  Call fasync() functions without the BKL
  snd/PCM: fasync BKL pushdown
  ipmi: fasync BKL pushdown
  ecryptfs: fasync BKL pushdown
  Bluetooth VHCI: fasync BKL pushdown
  tty_io: fasync BKL pushdown
  tun: fasync BKL pushdown
  i2o: fasync BKL pushdown
  mpt: fasync BKL pushdown
  Remove BKL from remote_llseek v2
  Make FAT users happier by not deadlocking
  x86-mce: BKL pushdown
  vmwatchdog: BKL pushdown
  vmcp: BKL pushdown
  via-pmu: BKL pushdown
  uml-random: BKL pushdown
  uml-mmapper: BKL pushdown
  ...
2008-07-14 14:48:31 -07:00
Jonathan Corbet 2fceef397f Merge commit 'v2.6.26' into bkl-removal 2008-07-14 15:29:34 -06:00
Linus Torvalds 17489c058e Merge branch 'sched/for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'sched/for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (76 commits)
  sched_clock: and multiplier for TSC to gtod drift
  sched_clock: record TSC after gtod
  sched_clock: only update deltas with local reads.
  sched_clock: fix calculation of other CPU
  sched_clock: stop maximum check on NO HZ
  sched_clock: widen the max and min time
  sched_clock: record from last tick
  sched: fix accounting in task delay accounting & migration
  sched: add avg-overlap support to RT tasks
  sched: terminate newidle balancing once at least one task has moved over
  sched: fix warning
  sched: build fix
  sched: sched_clock_cpu() based cpu_clock(), lockdep fix
  sched: export cpu_clock
  sched: make sched_{rt,fair}.c ifdefs more readable
  sched: bias effective_load() error towards failing wake_affine().
  sched: incremental effective_load()
  sched: correct wakeup weight calculations
  sched: fix mult overflow
  sched: update shares on wakeup
  ...
2008-07-14 13:54:49 -07:00
Linus Torvalds a3da5bf84a Merge branch 'x86/for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86/for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (821 commits)
  x86: make 64bit hpet_set_mapping to use ioremap too, v2
  x86: get x86_phys_bits early
  x86: max_low_pfn_mapped fix #4
  x86: change _node_to_cpumask_ptr to return const ptr
  x86: I/O APIC: remove an IRQ2-mask hack
  x86: fix numaq_tsc_disable calling
  x86, e820: remove end_user_pfn
  x86: max_low_pfn_mapped fix, #3
  x86: max_low_pfn_mapped fix, #2
  x86: max_low_pfn_mapped fix, #1
  x86_64: fix delayed signals
  x86: remove conflicting nx6325 and nx6125 quirks
  x86: Recover timer_ack lost in the merge of the NMI watchdog
  x86: I/O APIC: Never configure IRQ2
  x86: L-APIC: Always fully configure IRQ0
  x86: L-APIC: Set IRQ0 as edge-triggered
  x86: merge dwarf2 headers
  x86: use AS_CFI instead of UNWIND_INFO
  x86: use ignore macro instead of hash comment
  x86: use matching CFI_ENDPROC
  ...
2008-07-14 13:43:24 -07:00
Linus Torvalds 847106ff62 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6: (25 commits)
  security: remove register_security hook
  security: remove dummy module fix
  security: remove dummy module
  security: remove unused sb_get_mnt_opts hook
  LSM/SELinux: show LSM mount options in /proc/mounts
  SELinux: allow fstype unknown to policy to use xattrs if present
  security: fix return of void-valued expressions
  SELinux: use do_each_thread as a proper do/while block
  SELinux: remove unused and shadowed addrlen variable
  SELinux: more user friendly unknown handling printk
  selinux: change handling of invalid classes (Was: Re: 2.6.26-rc5-mm1 selinux whine)
  SELinux: drop load_mutex in security_load_policy
  SELinux: fix off by 1 reference of class_to_string in context_struct_compute_av
  SELinux: open code sidtab lock
  SELinux: open code load_mutex
  SELinux: open code policy_rwlock
  selinux: fix endianness bug in network node address handling
  selinux: simplify ioctl checking
  SELinux: enable processes with mac_admin to get the raw inode contexts
  Security: split proc ptrace checking into read vs. attach
  ...
2008-07-14 13:36:55 -07:00
Linus Torvalds dddec01eb8 Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-block
* 'for-linus' of git://git.kernel.dk/linux-2.6-block: (37 commits)
  splice: fix generic_file_splice_read() race with page invalidation
  ramfs: enable splice write
  drivers/block/pktcdvd.c: avoid useless memset
  cdrom: revert commit 22a9189 (cdrom: use kmalloced buffers instead of buffers on stack)
  scsi: sr avoids useless buffer allocation
  block: blk_rq_map_kern uses the bounce buffers for stack buffers
  block: add blk_queue_update_dma_pad
  DAC960: push down BKL
  pktcdvd: push BKL down into driver
  paride: push ioctl down into driver
  block: use get_unaligned_* helpers
  block: extend queue_flag bitops
  block: request_module(): use format string
  Add bvec_merge_data to handle stacked devices and ->merge_bvec()
  block: integrity flags can't use bit ops on unsigned short
  cmdfilter: extend default read filter
  sg: fix odd style (extra parenthesis) introduced by cmd filter patch
  block: add bounce support to blk_rq_map_user_iov
  cfq-iosched: get rid of enable_idle being unused warning
  allow userspace to modify scsi command filter on per device basis
  ...
2008-07-14 13:15:14 -07:00
Thomas Gleixner 7dc9719682 Merge commit '900cfa46191a7d87cf1891924cb90499287fd235'; branches 'timers/nohz', 'timers/clocksource' and 'timers/posixtimers' into timers/for-linus 2008-07-14 18:09:05 +02:00
Ingo Molnar 5806b81ac1 Merge branch 'auto-ftrace-next' into tracing/for-linus
Conflicts:

	arch/x86/kernel/entry_32.S
	arch/x86/kernel/process_32.c
	arch/x86/kernel/process_64.c
	arch/x86/lib/Makefile
	include/asm-x86/irqflags.h
	kernel/Makefile
	kernel/sched.c

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-14 16:11:52 +02:00
Ingo Molnar d14c8a680c Merge branch 'sched/for-linus' into tracing/for-linus 2008-07-14 16:11:02 +02:00
Ingo Molnar 6712e299b7 Merge branch 'tracing/ftrace' into auto-ftrace-next 2008-07-14 15:58:35 +02:00
Ingo Molnar 873a6ed628 Merge commit 'v2.6.26' into sched/devel 2008-07-14 12:19:19 +02:00
Ingo Molnar 361833efac Merge branch 'sched/clock' into sched/devel 2008-07-14 12:19:13 +02:00
Ingo Molnar d12c1a3792 lockdep: fix kernel/fork.c warning
fix:

[    0.184011] ------------[ cut here ]------------
[    0.188011] WARNING: at kernel/fork.c:918 copy_process+0x1c0/0x1084()
[    0.192011] Pid: 0, comm: swapper Not tainted 2.6.26-tip-00351-g01d4a50-dirty #14521
[    0.196011]  [<c0135d48>] warn_on_slowpath+0x3c/0x60
[    0.200012]  [<c016f805>] ? __alloc_pages_internal+0x92/0x36b
[    0.208012]  [<c033de5e>] ? __spin_lock_init+0x24/0x4a
[    0.212012]  [<c01347e3>] copy_process+0x1c0/0x1084
[    0.216013]  [<c013575f>] do_fork+0xb8/0x1ad
[    0.220013]  [<c034f75e>] ? acpi_os_release_lock+0x8/0xa
[    0.228013]  [<c034ff7a>] ? acpi_os_vprintf+0x20/0x24
[    0.232014]  [<c01129ee>] kernel_thread+0x75/0x7d
[    0.236014]  [<c0a491eb>] ? kernel_init+0x0/0x24a
[    0.240014]  [<c0a491eb>] ? kernel_init+0x0/0x24a
[    0.244014]  [<c01151b0>] ? kernel_thread_helper+0x0/0x10
[    0.252015]  [<c06c6ac0>] rest_init+0x14/0x50
[    0.256015]  [<c0a498ce>] start_kernel+0x2b9/0x2c0
[    0.260015]  [<c0a4904f>] __init_begin+0x4f/0x57
[    0.264016]  =======================
[    0.268016] ---[ end trace 4eaa2a86a8e2da22 ]---
[    0.272016] enabled ExtINT on CPU#0

which occurs if CONFIG_TRACE_IRQFLAGS=y, CONFIG_DEBUG_LOCKDEP=y,
but CONFIG_PROVE_LOCKING is disabled.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-14 12:09:28 +02:00
Ingo Molnar d59fdcf2ac Merge commit 'v2.6.26' into x86/core 2008-07-14 11:37:46 +02:00
Ingo Molnar 992860e991 lockdep: fix ftrace irq tracing false positive
fix this false positive:

[    0.020000] ------------[ cut here ]------------
[    0.020000] WARNING: at kernel/lockdep.c:2718 check_flags+0x14a/0x170()
[    0.020000] Modules linked in:
[    0.020000] Pid: 0, comm: swapper Not tainted 2.6.26-tip-00343-gd7e5521-dirty #14486
[    0.020000]  [<c01312e4>] warn_on_slowpath+0x54/0x80
[    0.020000]  [<c067e451>] ? _spin_unlock_irqrestore+0x61/0x70
[    0.020000]  [<c0131bb1>] ? release_console_sem+0x201/0x210
[    0.020000]  [<c0143d65>] ? __kernel_text_address+0x35/0x40
[    0.020000]  [<c010562e>] ? dump_trace+0x5e/0x140
[    0.020000]  [<c01518b5>] ? __lock_acquire+0x245/0x820
[    0.020000]  [<c015063a>] check_flags+0x14a/0x170
[    0.020000]  [<c0151ed8>] ? lock_acquire+0x48/0xc0
[    0.020000]  [<c0151ee1>] lock_acquire+0x51/0xc0
[    0.020000]  [<c014a16c>] ? down+0x2c/0x40
[    0.020000]  [<c010a609>] ? sched_clock+0x9/0x10
[    0.020000]  [<c067e7b2>] _write_lock+0x32/0x60
[    0.020000]  [<c013797f>] ? request_resource+0x1f/0xb0
[    0.020000]  [<c013797f>] request_resource+0x1f/0xb0
[    0.020000]  [<c02f89ad>] vgacon_startup+0x2bd/0x3e0
[    0.020000]  [<c094d62a>] con_init+0x19/0x22f
[    0.020000]  [<c0330c7c>] ? tty_register_ldisc+0x5c/0x70
[    0.020000]  [<c094cf49>] console_init+0x20/0x2e
[    0.020000]  [<c092a969>] start_kernel+0x20c/0x379
[    0.020000]  [<c092a516>] ? unknown_bootoption+0x0/0x1f6
[    0.020000]  [<c092a099>] __init_begin+0x99/0xa1
[    0.020000]  =======================
[    0.020000] ---[ end trace 4eaa2a86a8e2da22 ]---
[    0.020000] possible reason: unannotated irqs-on.
[    0.020000] irq event stamp: 0

which occurs if CONFIG_TRACE_IRQFLAGS=y, CONFIG_DEBUG_LOCKDEP=y,
but CONFIG_PROVE_LOCKING is disabled.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-14 10:32:14 +02:00
Ingo Molnar b4ba0ba24b Merge commit 'v2.6.26' into core/locking 2008-07-14 10:31:59 +02:00
Stephen Smalley 006ebb40d3 Security: split proc ptrace checking into read vs. attach
Enable security modules to distinguish reading of process state via
proc from full ptrace access by renaming ptrace_may_attach to
ptrace_may_access and adding a mode argument indicating whether only
read access or full attach access is requested.  This allows security
modules to permit access to reading process state without granting
full ptrace access.  The base DAC/capability checking remains unchanged.

Read access to /proc/pid/mem continues to apply a full ptrace attach
check since check_mem_permission() already requires the current task
to already be ptracing the target.  The other ptrace checks within
proc for elements like environ, maps, and fds are changed to pass the
read mode instead of attach.

In the SELinux case, we model such reading of process state as a
reading of a proc file labeled with the target process' label.  This
enables SELinux policy to permit such reading of process state without
permitting control or manipulation of the target process, as there are
a number of cases where programs probe for such information via proc
but do not need to be able to control the target (e.g. procps,
lsof, PolicyKit, ConsoleKit).  At present we have to choose between
allowing full ptrace in policy (more permissive than required/desired)
or breaking functionality (or in some cases just silencing the denials
via dontaudit rules but this can hide genuine attacks).

This version of the patch incorporates comments from Casey Schaufler
(change/replace existing ptrace_may_attach interface, pass access
mode), and Chris Wright (provide greater consistency in the checking).

Note that like their predecessors __ptrace_may_attach and
ptrace_may_attach, the __ptrace_may_access and ptrace_may_access
interfaces use different return value conventions from each other (0
or -errno vs. 1 or 0).  I retained this difference to avoid any
changes to the caller logic but made the difference clearer by
changing the latter interface to return a bool rather than an int and
by adding a comment about it to ptrace.h for any future callers.

Signed-off-by:  Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: James Morris <jmorris@namei.org>
2008-07-14 15:01:47 +10:00
Lai Jiangshan 199a952876 rcu classic: update qlen when cpu offline
When callbacks are moved from offline cpu to this cpu,
the qlen field of this rdp should be updated.

[ Paul E. McKenney: ]

The effect of this bug would be for force_quiescent_state() to be invoked
when it should not and vice versa -- wasting cycles in the first case
and letting RCU callbacks remain piled up in the second case.  The bug
is thus "benign" in that it does not result in premature grace-period
termination, but should of course be fixed nonetheless.

Preemption is disabled by the caller's get_cpu_var(), so we are guaranteed
to remain on the same CPU, as required.  The local_irq_disable() is indeed
needed, otherwise, an interrupt might invoke call_rcu() or call_rcu_bh(),
which could cause that interrupt's increment of ->qlen to be lost.

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-13 23:12:17 +02:00
Linus Torvalds 3b5c6b8349 Merge branch 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  cpusets, hotplug, scheduler: fix scheduler domain breakage
2008-07-13 11:03:59 -07:00
Dmitry Adamushko 3e84050c81 cpusets, hotplug, scheduler: fix scheduler domain breakage
Commit f18f982ab ("sched: CPU hotplug events must not destroy scheduler
domains created by the cpusets") introduced a hotplug-related problem as
described below:

Upon CPU_DOWN_PREPARE,

  update_sched_domains() -> detach_destroy_domains(&cpu_online_map)

does the following:

/*
 * Force a reinitialization of the sched domains hierarchy. The domains
 * and groups cannot be updated in place without racing with the balancing
 * code, so we temporarily attach all running cpus to the NULL domain
 * which will prevent rebalancing while the sched domains are recalculated.
 */

The sched-domains should be rebuilt when a CPU_DOWN ops. has been
completed, effectively either upon CPU_DEAD{_FROZEN} (upon success) or
CPU_DOWN_FAILED{_FROZEN} (upon failure -- restore the things to their
initial state). That's what update_sched_domains() also does but only
for !CPUSETS case.

With f18f982ab, sched-domains' reinitialization is delegated to
CPUSETS code:

cpuset_handle_cpuhp() -> common_cpu_mem_hotplug_unplug() ->
rebuild_sched_domains()

Being called for CPU_UP_PREPARE and if its callback is called after
update_sched_domains()), it just negates all the work done by
update_sched_domains() -- i.e. a soon-to-be-offline cpu is included in
the sched-domains and that makes it visible for the load-balancer
while the CPU_DOWN ops. is in progress.

__migrate_live_tasks() moves the tasks off a 'dead' cpu (it's already
"offline" when this function is called).

try_to_wake_up() is called for one of these tasks from another CPU ->
the load-balancer (wake_idle()) picks up a "dead" CPU and places the
task on it. Then e.g. BUG_ON(rq->nr_running) detects this a bit later
-> oops.

Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Tested-by: Vegard Nossum <vegard.nossum@gmail.com>
Cc: Paul Menage <menage@google.com>
Cc: Max Krasnyansky <maxk@qualcomm.com>
Cc: Paul Jackson <pj@sgi.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: miaox@cn.fujitsu.com
Cc: rostedt@goodmis.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-13 11:37:02 +02:00
Ingo Molnar 54ef76f37b Merge branch 'linus' into sched/devel 2008-07-13 08:50:13 +02:00
Ingo Molnar ae94b8075a Merge branch 'linus' into x86/core
Conflicts:

	arch/x86/mm/ioremap.c

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-12 07:29:02 +02:00
Ingo Molnar b2613e370d ftrace: build fix for ftraced_suspend
fix:

 kernel/trace/ftrace.c:1615: error: 'ftraced_suspend' undeclared (first use in this function)
 kernel/trace/ftrace.c:1615: error: (Each undeclared identifier is reported only once
 kernel/trace/ftrace.c:1615: error: for each function it appears in.)

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-11 16:46:50 +02:00
Steven Rostedt c300ba2528 sched_clock: and multiplier for TSC to gtod drift
The sched_clock code currently tries to keep all CPU clocks of all CPUS
somewhat in sync. At every clock tick it records the gtod clock and
uses that and jiffies and the TSC to calculate a CPU clock that tries to
stay in sync with all the other CPUs.

ftrace depends heavily on this timer and it detects when this timer
"jumps".  One problem is that the TSC and the gtod also drift.
When the TSC is 0.1% faster or slower than the gtod it is very noticeable
in ftrace. To help compensate for this, I've added a multiplier that
tries to keep the CPU clock updating at the same rate as the gtod.

I've tried various ways to get it to be in sync and this ended up being
the most reliable. At every scheduler tick we calculate the new multiplier:

  multi = delta_gtod / delta_TSC

This means we perform a 64 bit divide at the tick (once a HZ). A shift
is used to handle the accuracy.

Other methods that failed due to dynamic HZ are:

(not used)  multi += (gtod - tsc) / delta_gtod
(not used)  multi += (gtod - (last_tsc + delta_tsc)) / delta_gtod

as well as other variants.

This code still allows for a slight drift between TSC and gtod, but
it keeps the damage down to a minimum.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Steven Rostedt <srostedt@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: john stultz <johnstul@us.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-11 15:53:28 +02:00
Steven Rostedt a83bc47c33 sched_clock: record TSC after gtod
To read the gtod we need to grab the xtime lock for read. Reading the gtod
before the TSC can cause a bigger gab if the xtime lock is contended.

This patch simply reverses the order to read the TSC after the gtod.
The locking in the reading of the gtod handles any barriers one might
think is needed.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Steven Rostedt <srostedt@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: john stultz <johnstul@us.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-11 15:53:27 +02:00
Steven Rostedt c0c87734f1 sched_clock: only update deltas with local reads.
Reading the CPU clock should try to stay accurate within the CPU.
By reading the CPU clock from another CPU and updating the deltas can
cause unneeded jumps when reading from the local CPU.

This patch changes the code to update the last read TSC only when read
from the local CPU.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Steven Rostedt <srostedt@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: john stultz <johnstul@us.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-11 15:53:27 +02:00
Steven Rostedt 2b8a0cf489 sched_clock: fix calculation of other CPU
The algorithm to calculate the 'now' of another CPU is not correct.
At each scheduler tick, each CPU records the last sched_clock and
gtod (tick_raw and tick_gtod respectively). If the TSC is somewhat the
same in speed between two clocks the algorithm would be:

  tick_gtod1 + (now1 - tick_raw1) = tick_gtod2 + (now2 - tick_raw2)

To calculate now2 we would have:

  now2 = (tick_gtod1 - tick_gtod2) + (tick_raw2 - tick_raw1) + now1

Currently the algorithm is:

  now2 = (tick_gtod1 - tick_gtod2) + (tick_raw1 - tick_raw2) + now1

This solves most of the rest of the issues I've had with timestamps in
ftace.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-11 15:53:26 +02:00
Steven Rostedt af52a90a14 sched_clock: stop maximum check on NO HZ
Working with ftrace I would get large jumps of 11 millisecs or more with
the clock tracer. This killed the latencing timings of ftrace and also
caused the irqoff self tests to fail.

What was happening is with NO_HZ the idle would stop the jiffy counter and
before the jiffy counter was updated the sched_clock would have a bad
delta jiffies to compare with the gtod with the maximum.

The jiffies would stop and the last sched_tick would record the last gtod.
On wakeup, the sched clock update would compare the gtod + delta jiffies
(which would be zero) and compare it to the TSC. The TSC would have
correctly (with a stable TSC) moved forward several jiffies. But because the
jiffies has not been updated yet the clock would be prevented from moving
forward because it would appear that the TSC jumped too far ahead.

The clock would then virtually stop, until the jiffies are updated. Then
the next sched clock update would see that the clock was very much behind
since the delta jiffies is now correct. This would then jump the clock
forward by several jiffies.

This caused ftrace to report several milliseconds of interrupts off
latency at every resume from NO_HZ idle.

This patch adds hooks into the nohz code to disable the checking of the
maximum clock update when nohz is in effect. It resumes the max check
when nohz has updated the jiffies again.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Steven Rostedt <srostedt@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-11 15:53:26 +02:00
Steven Rostedt f7cce27f56 sched_clock: widen the max and min time
With keeping the max and min sched time within one jiffy of the gtod clock
was too tight. Just before a schedule tick the max could easily be hit, as
well as just after a schedule_tick the min could be hit. This caused the
clock to jump around by a jiffy.

This patch widens the minimum to
   last gtod + (delta_jiffies ? delta_jiffies - 1 : 0) * TICK_NSECS

and the maximum to
    last gtod + (2 + delta_jiffies) * TICK_NSECS

This keeps the minum to gtod or if one jiffy less than delta jiffies
and the maxim 2 jiffies ahead of gtod. This may cause unstable TSCs to be
a bit more sporadic, but it helps keep a clock with a stable TSC working well.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Steven Rostedt <srostedt@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-11 15:53:25 +02:00
Steven Rostedt 62c43dd986 sched_clock: record from last tick
The sched_clock code tries to keep within the gtod time by one tick (jiffy).
The current code mistakenly keeps track of the delta jiffies between
updates of the clock, where the the delta is used to compare with the
number of jiffies that have past since an update of the gtod. The gtod is
updated at each schedule tick not each sched_clock update. After one
jiffy passes the clock is updated fine. But the delta is taken from the
last update so if the next update happens before the next tick the delta
jiffies used will be incorrect.

This patch changes the code to check the delta of jiffies between ticks
and not updates to match the comparison of the updates with the gtod.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Steven Rostedt <srostedt@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-11 15:53:25 +02:00
Steven Rostedt 60bc080090 ftrace: separate out the function enabled variable
Currently the function tracer uses the global tracer_enabled variable that
is used to keep track if the tracer is enabled or not. The function tracing
startup needs to be separated out, otherwise the internal happenings of
the tracer startup is also recorded.

This patch creates a ftrace_function_enabled variable to all the starting
of the function traces to happen after everything has been started.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Steven Rostedt <srostedt@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-11 15:49:22 +02:00
Steven Rostedt a2bb6a3d85 ftrace: add ftrace_kill_atomic
It has been suggested that I add a way to disable the function tracer
on an oops. This code adds a ftrace_kill_atomic. It is not meant to be
used in normal situations. It will disable the ftrace tracer, but will
not perform the nice shutdown that requires scheduling.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Steven Rostedt <srostedt@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-11 15:49:21 +02:00
Steven Rostedt 26bc83f4cb ftrace: use current CPU for function startup
This is more of a clean up. Currently the function tracer initializes the
tracer with which ever CPU was last used for tracing. This value isn't
realy useful for function tracing, but at least it should be something other
than a random number.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Steven Rostedt <srostedt@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-11 15:49:21 +02:00
Steven Rostedt ad591240ce ftrace: start wakeup tracing after setting function tracer
Enabling the wakeup tracer before enabling the function tracing causes
some strange results due to the dynamic enabling of the functions.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Steven Rostedt <srostedt@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-11 15:49:20 +02:00
Steven Rostedt b5c21b4514 ftrace: check proper config for preempt type
There is no CONFIG_PREEMPT_DESKTOP. Use the proper entry CONFIG_PREEMPT.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Steven Rostedt <srostedt@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-11 15:49:19 +02:00
Steven Rostedt 1e16c0a081 ftrace: trace schedule
After the sched_clock code has been removed from sched.c we can now trace
the scheduler. The scheduler has a lot of functions that would be worth
tracing.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Steven Rostedt <srostedt@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-11 15:49:19 +02:00
Steven Rostedt 001b6767b1 ftrace: define function trace nop
When CONFIG_FTRACE is not enabled, the tracing_start_functon_trace
and tracing_stop_function_trace should be nops.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Steven Rostedt <srostedt@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-11 15:49:18 +02:00
Steven Rostedt 007c05d4d2 ftrace: move sched_switch enable after markers
We have two markers now that are enabled on sched_switch. One that records
the context switching and the other that records task wake ups. Currently
we enable the tracing first and then set the markers. This causes some
confusing traces:

# tracer: sched_switch
#
#           TASK-PID   CPU#    TIMESTAMP  FUNCTION
#              | |      |          |         |
       trace-cmd-3973  [00]   115.834817:   3973:120:R   +     3:  0:S
       trace-cmd-3973  [01]   115.834910:   3973:120:R   +     6:  0:S
       trace-cmd-3973  [02]   115.834910:   3973:120:R   +     9:  0:S
       trace-cmd-3973  [03]   115.834910:   3973:120:R   +    12:  0:S
       trace-cmd-3973  [02]   115.834910:   3973:120:R   +     9:  0:S
          <idle>-0     [02]   115.834910:      0:140:R ==>  3973:120:R

Here we see that trace-cmd with PID 3973 wakes up task 9 but the next line
shows the idle task doing a context switch to task 3973.

Enabling the tracing to _after_ the markers are set creates a much saner
output:

# tracer: sched_switch
#
#           TASK-PID   CPU#    TIMESTAMP  FUNCTION
#              | |      |          |         |
          <idle>-0     [02]  7922.634225:      0:140:R ==>  4790:120:R
       trace-cmd-4789  [03]  7922.634225:      0:140:R   +  4790:120:R

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Steven Rostedt <srostedt@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-11 15:49:18 +02:00
Heiko Carstens 857f3fd7a4 nohz: don't stop idle tick if softirqs are pending.
In case a cpu goes idle but softirqs are pending only an error message is
printed to the console. It may take a very long time until the pending
softirqs will finally be executed. Worst case would be a hanging system.

With this patch the timer tick just continues and the softirqs will be
executed after the next interrupt. Still a delay but better than a
hanging system.

Currently we have at least two device drivers on s390 which under certain
circumstances schedule a tasklet from process context. This is a reason
why we can end up with pending softirqs when going idle. Fixing these
drivers seems to be non-trivial.
However there is no question that the drivers should be fixed.
This patch shouldn't be considered as a bug fix. It just is intended to
keep a system running even if device drivers are buggy.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Jan Glauber <jan.glauber@de.ibm.com>
Cc: Stefan Weinhuber <wein@de.ibm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-11 11:17:04 +02:00
Ingo Molnar 0c81b2a144 Merge branch 'linus' into core/rcu
Conflicts:

	include/linux/rculist.h
	kernel/rcupreempt.c

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-11 10:46:50 +02:00
Linus Torvalds a26449daa2 Merge branch 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  sched: fix cpu hotplug, cleanup
  sched: fix cpu hotplug
2008-07-10 12:34:55 -07:00
Linus Torvalds b1e387348a sched: fix cpu hotplug, cleanup
Clean up __migrate_task(): to just have separate "done" and "fail"
cases, instead of that "out" case with random error behavior.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-10 20:39:58 +02:00
Nick Piggin 70ff05554f Fix PREEMPT_RCU without HOTPLUG_CPU
PREEMPT_RCU without HOTPLUG_CPU is broken.  The rcu_online_cpu is called
to initially populate rcu_cpu_online_map with all online CPUs when the
hotplug event handler is installed, and also to populate the map with
CPUs as they come online.  The former case is meant to happen with and
without HOTPLUG_CPU, but without HOTPLUG_CPU, the rcu_offline_cpu
function is no-oped -- while it still gets called, it does not set the
rcu CPU map.

With a blank RCU CPU map, grace periods get to tick by completely
oblivious to active RCU read side critical sections.  This results in
free-before-grace bugs.

Fix is obvious once the problem is known. (Also, change __devinit to
__cpuinit so the function gets thrown away on !HOTPLUG_CPU kernels).

Signed-off-by: Nick Piggin <npiggin@suse.de>
Reported-and-tested-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
[ Nick is my personal hero of the day - Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-10 11:13:44 -07:00
Daniel Guilak 544304b200 kernel/kprobes.c: Made kprobe_blacklist static.
Signed-off-by: Daniel Guilak <daniel@danielguilak.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-10 10:13:51 -07:00
Russell King f0006314d3 Merge branch 'imx' into devel
Conflicts:

	arch/arm/mm/Kconfig
2008-07-10 16:41:50 +01:00
Russell King a177ba3b7a Merge branches 'at91', 'dyntick', 'ep93xx', 'iop', 'ixp', 'misc', 'orion', 'omap-reviewed', 'rpc', 'rtc' and 's3c' into devel 2008-07-10 16:38:50 +01:00
Ingo Molnar ec1bb60bbf Merge branch 'tracing/sysprof' into auto-ftrace-next 2008-07-10 11:43:08 +02:00
Ingo Molnar 5373fdbdc1 Merge branch 'tracing/mmiotrace' into auto-ftrace-next 2008-07-10 11:43:06 +02:00
Ingo Molnar bac0c9103b Merge branch 'tracing/ftrace' into auto-ftrace-next 2008-07-10 11:43:00 +02:00
Dmitry Adamushko dc7fab8b3b sched: fix cpu hotplug
I think we may have a race between try_to_wake_up() and
migrate_live_tasks() -> move_task_off_dead_cpu() when the later one
may end up looping endlessly.

Interrupts are enabled on other CPUs when migration_call(CPU_DEAD, ...) is
called so we may get a race between try_to_wake_up() and
migrate_live_tasks() -> move_task_off_dead_cpu(). The former one may push
a task out of a dead CPU causing the later one to loop endlessly.

Heiko Carstens observed:

| That's exactly what explains a dump I got yesterday. Thanks for fixing! :)

Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Cc: miaox@cn.fujitsu.com
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Avi Kivity <avi@qumranet.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-10 09:35:34 +02:00