Clean up hungarian notation from timer code.
Signed-off-by: NPavel Machek <pavel@suse.cz>
Cc: john stultz <johnstul@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

When trying to load a module with the same name as a built-in one, a
scary kobject backtrace comes up.  Prevent that from checking for this
condition and warning the user as to what exactly is going on.

Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

The struct module taints member is supposed to store per-module taint
data. The kernel knows about certain specific external modules that will
taint the kernel, such as ndiswrapper. Use of ndiswrapper possibly
should set the per-module taint in addition to the global kernel
taint flag, unless we're arguing not because wrapper module itself
is not what actually causes the kernel to be tainted as such?
Signed-off-by: NJon Masters <jcm@jonmasters.org>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

the original code use KOBJ_NAME_LEN for built-in module name length,
that's defined to 20 in linux/kobject.h, but this is not enough appearntly,
many module names are longer than this;
 #define KOBJ_NAME_LEN                   20

another macro is MODULE_NAME_LEN defined in linux/module.h, I think this is
enough for module names:
 #define MODULE_NAME_LEN (64 - sizeof(unsigned long))
Signed-off-by: NDenis Cheng <crquan@gmail.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

module_address_lookup releases preemption then returns a pointer into
the module space.  The only user (kallsyms) copies the result, so just
do that under the preempt disable.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

If we put the module in the linked list *before* calling into to, we
get the module name and functions in the OOPS (is_module_address can
find the module).  It also helps lockdep in a similar way.
Acked-and-tested-by: NJoern Engel <joern@lazybastard.org>
Tested-by: NErez Zadok <ezk@cs.sunysb.edu>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

Andrew sent an older version of this patch: we shouldn't use sprintf
to copy a string.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

There have been reports of modules failing to load because the modules
they depend on are still loading.  This changes the modules to wait
for a reasonable length of time in that case.  We time out eventually,
because there can be module loops or broken modules.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

Current code could cause a bug in symbol_put_addr() if an arch used
kmalloc module text: we might think the symbol belongs to the core
kernel.

The downside is that this might make backtraces through (discarded)
init functions harder to read on some archs, but we already have that
issue for modules and noone has complained.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

I have removed all the entries from this table (core_table,
ipv4_table and tr_table), so now we can safely drop it.
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch implements the basic infrastructure for per namespace sysctls.

A list of lists of sysctl headers is added, allowing each namespace to have
it's own list of sysctl headers.

Each list of sysctl headers has a lookup function to find the first
sysctl header in the list, allowing the lists to have a per namespace
instance.

register_sysct_root is added to tell sysctl.c about additional
lists of sysctl_headers.  As all of the users are expected to be in
kernel no unregister function is provided.

sysctl_head_next is updated to walk through the list of lists.

__register_sysctl_paths is added to add a new sysctl table on
a non-default sysctl list.

The only intrusive part of this patch is propagating the information
to decided which list of sysctls to use for sysctl_check_table.
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Cc: Serge Hallyn <serue@us.ibm.com>
Cc: Daniel Lezcano <dlezcano@fr.ibm.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

By doing this we allow users of register_sysctl_paths that build
and dynamically allocate their ctl_table to be simpler.  This allows
them to just remember the ctl_table_header returned from
register_sysctl_paths from which they can now find the
ctl_table array they need to free.
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Cc: Serge Hallyn <serue@us.ibm.com>
Cc: Daniel Lezcano <dlezcano@fr.ibm.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There are a number of modules that register a sysctl table
somewhere deeply nested in the sysctl hierarchy, such as
fs/nfs, fs/xfs, dev/cdrom, etc.

They all specify several dummy ctl_tables for the path name.
This patch implements register_sysctl_path that takes
an additional path name, and makes up dummy sysctl nodes
for each component.

This patch was originally written by Olaf Kirch and
brought to my attention and reworked some by Olaf Hering.
I have changed a few additional things so the bugs are mine.

After converting all of the easy callers Olaf Hering observed
allyesconfig ARCH=i386, the patch reduces the final binary size by 9369 bytes.

.text +897
.data -7008

   text    data     bss     dec     hex filename
   26959310        4045899 4718592 35723801        2211a19 ../vmlinux-vanilla
   26960207        4038891 4718592 35717690        221023a ../O-allyesconfig/vmlinux

So this change is both a space savings and a code simplification.

CC: Olaf Kirch <okir@suse.de>
CC: Olaf Hering <olaf@aepfle.de>
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Cc: Serge Hallyn <serue@us.ibm.com>
Cc: Daniel Lezcano <dlezcano@fr.ibm.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

syslets (or other threads/processes that want io context sharing) can
set this to enforce sharing of io context.
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

Detach task state from ioc, instead keep track of how many processes
are accessing the ioc.
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

This is where it belongs and then it doesn't take up space for a
process that doesn't do IO.
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

revert 19ef9309.

Kevin Winchester reported a lockup during X startup an bisected
it to this commit.
Reported-by: NKevin Winchester <kjwinchester@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Forgot to remove this when removing the appldata binary sysctls.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Right now, the linux kernel (with scheduler statistics enabled) keeps track
of the maximum time a process is waiting to be scheduled. While the maximum
is a very useful metric, tracking average and total is equally useful
(at least for latencytop) to figure out the accumulated effect of scheduler
delays. The accumulated effect is important to judge the performance impact
of scheduler tuning/behavior.
Signed-off-by: NArjan van de Ven <arjan@linux.intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

print_cfs_stats is callable from interrupt context (sysrq), hence it should
not take mutexes. Change it to use RCU since the task group data is RCU
freed anyway.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

The attached patch is something really simple that can sometimes help
in getting more info out of a hung system.
Signed-off-by: NIngo Molnar <mingo@elte.hu>

printk timestamps: use ktime_get().

Some platforms have a functioning clocksource function only after
they are done with early bootup, so delay this until out of
SYSTEM_BOOTING state.

it's also inherently safe now, as any bugs in this area will be
caught by the printk recursion checks.
Signed-off-by: NIngo Molnar <mingo@elte.hu>

fix softlockup tunables signedness.

mark tunables read-mostly.
Signed-off-by: NIngo Molnar <mingo@elte.hu>

LatencyTOP kernel infrastructure; it measures latencies in the
scheduler and tracks it system wide and per process.
Signed-off-by: NArjan van de Ven <arjan@linux.intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

looking at it one more time:

(1) it looks to me that there is no need to call
sched_rt_ratio_exceeded() from pick_next_rt_entity()

- [ for CONFIG_FAIR_GROUP_SCHED ] queues with rt_rq->rt_throttled are
not within this 'tree-like hierarchy' (or whatever we should call it
:-)

- there is also no need to re-check 'rt_rq->rt_time > ratio' at this
point as 'rt_rq->rt_time' couldn't have been increased since the last
call to update_curr_rt() (which obviously calls
sched_rt_ratio_esceeded())
well, it might be that 'ratio' for this rt_rq has been re-configured
(and the period over which this rt_rq was active has not yet been
finished)... but I don't think we should really take this into
account.

(2) now pick_next_rt_entity() must never return NULL, so let's change
pick_next_task_rt() accordingly.
Signed-off-by: NDmitry Adamushko <dmitry.adamushko@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

We monitor clock overflows, let's also monitor clock underflows.
Signed-off-by: NGuillaume Chazarain <guichaz@yahoo.fr>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

sched: fix rq->clock warps on frequency changes

Fix 2bacec8c
(sched: touch softlockup watchdog after idling) that reintroduced warps
on frequency changes. touch_softlockup_watchdog() calls __update_rq_clock
that checks rq->clock for warps, so call it after adjusting rq->clock.
Signed-off-by: NGuillaume Chazarain <guichaz@yahoo.fr>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Ensure that the kernel threads are created with the usual nice level
and affinity even if kthreadd's properties were changed from the
default by root.
Signed-off-by: NMichal Schmidt <mschmidt@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

 Before:
 total: 25 errors, 13 warnings, 602 lines checked

 After:
 total: 0 errors, 2 warnings, 601 lines checked

No code changed:

kernel/profile.o:
   text    data     bss     dec     hex filename
   3048     236      24    3308     cec profile.o.before
   3048     236      24    3308     cec profile.o.after
 md5:
   2501d64748a4d350dffb11203e2a5182  profile.o.before.asm
   2501d64748a4d350dffb11203e2a5182  profile.o.after.asm
Signed-off-by: NPaolo Ciarrocchi <paolo.ciarrocchi@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

remove the !PREEMPT_BKL code.

this removes 160 lines of legacy code.
Signed-off-by: NIngo Molnar <mingo@elte.hu>

make PREEMPT_BKL the default.

precursor to removal of the !PREEMPT_BKL code.
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Based on a suggestion from Andi:

 In various cases, the unload of a module may leave some bad state around
 that causes a kernel crash AFTER a module is unloaded; and it's then hard
 to find which module caused that.

This patch tracks the last unloaded module, and prints this as part of the
module list in the oops trace.

Right now, only the last 1 module is tracked; I expect that this is enough
for the vast majority of cases where this information matters; if it turns
out that tracking more is important, we can always extend it to that.

[ mingo@elte.hu: build fix ]
Signed-off-by: NArjan van de Ven <arjan@linux.intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

It's rather common that an oops/WARN_ON/BUG happens during the load or
unload of a module. Unfortunatly, it's not always easy to see directly
which module is being loaded/unloaded from the oops itself. Worse,
it's not even always possible to ask the bug reporter, since there
are so many components (udev etc) that auto-load modules that there's
a good chance that even the reporter doesn't know which module this is.

This patch extends the existing "show if it's tainting" print code,
which is used as part of printing the modules in the oops/BUG/WARN_ON
to include a "+" for "being loaded" and a "-" for "being unloaded".

As a result this extension, the "taint_flags()" function gets renamed to
"module_flags()" (and takes a module struct as argument, not a taint
flags int).
Signed-off-by: NArjan van de Ven <arjan@linux.intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Remove the curious logic to set it_sched_expires in the future. It useless
because rt.timeout wouldn't be incremented anyway.

Explicity check for RLIM_INFINITY as a test programm that had a 1s soft limit
and a inf hard limit would SIGKILL at 1s. This is because RLIM_INFINITY+d-1
is d-2.
Signed-off-by: NPeter Zijlsta <a.p.zijlstra@chello.nl>
CC: Michal Schmidt <mschmidt@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Only reschedule if the new group has a higher prio task.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

hrtimer_wakeup creates a

  base->lock
    rq->lock

lock dependancy. Avoid this by switching to HRTIMER_CB_IRQSAFE_NO_SOFTIRQ
which doesn't hold base->lock.

This fully untangles hrtimer locks from the scheduler locks, and allows
hrtimer usage in the scheduler proper.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Currently all highres=off timers are run from softirq context, but
HRTIMER_CB_IRQSAFE_NO_SOFTIRQ timers expect to run from irq context.

Fix this up by splitting it similar to the highres=on case.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

In order to more easily allow for the scheduler to use timers, clean up
the locking a bit.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

We need to teach no_hz about the rt throttling because its tick driven.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

"goto out" is an odd way to spell "skip".
Signed-off-by: NMike Galbraith <efault@gmx.de>
Signed-off-by: NIngo Molnar <mingo@elte.hu>