Convert the 'dynamic debug' infrastructure to use jump labels.
Signed-off-by: NJason Baron <jbaron@redhat.com>
LKML-Reference: <b77627358cea3e27d7be4386f45f66219afb8452.1284733808.git.jbaron@redhat.com>
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>

Make use of the jump label infrastructure for tracepoints.
Signed-off-by: NJason Baron <jbaron@redhat.com>
LKML-Reference: <a9ba2056e2c9cf332c3c300b577463ce66ff23a8.1284733808.git.jbaron@redhat.com>
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>

Add a jump_label_text_reserved(void *start, void *end), so that other
pieces of code that want to modify kernel text, can first verify that
jump label has not reserved the instruction.
Acked-by: NMasami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: NJason Baron <jbaron@redhat.com>
LKML-Reference: <06236663a3a7b1c1f13576bb9eccb6d9c17b7bfe.1284733808.git.jbaron@redhat.com>
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>

Initialize the workqueue data structures *before* they are registered
so that they are ready for callbacks.
Signed-off-by: NJason Baron <jbaron@redhat.com>
LKML-Reference: <e3a3383fc370ac7086625bebe89d9480d7caf372.1284733808.git.jbaron@redhat.com>
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>

base patch to implement 'jump labeling'. Based on a new 'asm goto' inline
assembly gcc mechanism, we can now branch to labels from an 'asm goto'
statment. This allows us to create a 'no-op' fastpath, which can subsequently
be patched with a jump to the slowpath code. This is useful for code which
might be rarely used, but which we'd like to be able to call, if needed.
Tracepoints are the current usecase that these are being implemented for.
Acked-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NJason Baron <jbaron@redhat.com>
LKML-Reference: <ee8b3595967989fdaf84e698dc7447d315ce972a.1284733808.git.jbaron@redhat.com>

[ cleaned up some formating ]
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>

Make text_poke_early available outside of alternative.c. The jump label
patchset wants to make use of it in order to set up the optimal no-op
sequences at run-time.
Signed-off-by: NJason Baron <jbaron@redhat.com>
LKML-Reference: <04cfddf2ba77bcabfc3e524f1849d871d6a1cf9d.1284733808.git.jbaron@redhat.com>
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>

Move Steve's code for finding the best 5-byte no-op from ftrace.c to
alternative.c. The idea is that other consumers (in this case jump label)
want to make use of that code.
Signed-off-by: NJason Baron <jbaron@redhat.com>
LKML-Reference: <96259ae74172dcac99c0020c249743c523a92e18.1284733808.git.jbaron@redhat.com>
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>

Revert the timer per cpu-context timers because of unfortunate
nohz interaction. Fixing that would have been somewhat ugly, so
go back to driving things from the regular tick. Provide a
jiffies interval feature for people who want slower rotations.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <20100917093009.519845633@chello.nl>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Use the right cpu-context.. spotted by preempt warning on
hot-unplug
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Cc: Robert Richter <robert.richter@amd.com>
LKML-Reference: <20100917093009.461794357@chello.nl>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Aside from allowing software events into a !software group,
allow adding !software events to pure software groups.

Once we've moved the software group and attached the first
!software event, the group will no longer be a pure software
group and hence no longer be eligible for movement, at which
point the straight ctx comparison is correct again.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <20100917093009.410784731@chello.nl>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Events were not grouped anymore. The reason was that in
perf_event_open(), the field event->group_leader was
initialized before the function looked up the group_fd
to find the event leader. This patch fixes this by
reordering the code correctly.
Signed-off-by: NStephane Eranian <eranian@google.com>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Robert Richter <robert.richter@amd.com>
LKML-Reference: <20100917093009.360420946@chello.nl>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This patch adds new generic events for dynamic power management
tracing:

 - clock events class: used for clock enable/disable and for
   clock rate change,
 - power_domain events class: used for power domains transitions.

The OMAP architecture will be using the new events for PM debugging,
however the new events are made generic enough to be used by all
platforms.
Signed-off-by: NJean Pihet <j-pihet@ti.com>
Acked-by: NThomas Renninger <trenn@suse.de>
Cc: discuss@lesswatts.org
Cc: linux-pm@lists.linux-foundation.org
Cc: Thomas Renninger <trenn@suse.de>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Len Brown <len.brown@intel.com>
Cc: Kevin Hilman <khilman@deeprootsystems.com>
LKML-Reference: <AANLkTinUmbSUUuxUzc8++pcb9gd1CZFdyTQFrveTBXyV@mail.gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This removes following warnings when build with C=1

 warning: context imbalance in 'kretprobe_hash_lock' - wrong count at exit
 warning: context imbalance in 'kretprobe_table_lock' - wrong count at exit
 warning: context imbalance in 'kretprobe_hash_unlock' - unexpected unlock
 warning: context imbalance in 'kretprobe_table_unlock' - unexpected unlock
Signed-off-by: NNamhyung Kim <namhyung@gmail.com>
Acked-by: NMasami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
LKML-Reference: <1284512670-2369-6-git-send-email-namhyung@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Remove __dummy_buf which is needed for kallsyms_lookup only.
use kallsysm_lookup_size_offset instead.
Signed-off-by: NNamhyung Kim <namhyung@gmail.com>
Acked-by: NMasami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
LKML-Reference: <1284512670-2369-5-git-send-email-namhyung@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Make following (internal) functions static to make sparse
happier :-)

 * get_optimized_kprobe: only called from static functions
 * kretprobe_table_unlock: _lock function is static
 * kprobes_optinsn_template_holder: never called but holding asm code
Signed-off-by: NNamhyung Kim <namhyung@gmail.com>
Acked-by: NMasami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
LKML-Reference: <1284512670-2369-4-git-send-email-namhyung@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Verify jprobe's entry point is a function entry point
using kallsyms' offset value.
Signed-off-by: NNamhyung Kim <namhyung@gmail.com>
Acked-by: NMasami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
LKML-Reference: <1284512670-2369-3-git-send-email-namhyung@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Remove call to kernel_text_address() in register_jprobes()
because it is called right after in register_kprobe().
Signed-off-by: NNamhyung Kim <namhyung@gmail.com>
Acked-by: NMasami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
LKML-Reference: <1284512670-2369-2-git-send-email-namhyung@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

The kernel perf event creation path shouldn't use find_task_by_vpid()
because a vpid exists in a specific namespace. find_task_by_vpid() uses
current's pid namespace which isn't always the correct namespace to use
for the vpid in all the places perf_event_create_kernel_counter() (and
thus find_get_context()) is called.

The goal is to clean up pid namespace handling and prevent bugs like:

	https://bugzilla.kernel.org/show_bug.cgi?id=17281

Instead of using pids switch find_get_context() to use task struct
pointers directly. The syscall is responsible for resolving the pid to
a task struct. This moves the pid namespace resolution into the syscall
much like every other syscall that takes pid parameters.
Signed-off-by: NMatt Helsley <matthltc@us.ibm.com>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Robin Green <greenrd@greenrd.org>
Cc: Prasad <prasad@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
LKML-Reference: <a134e5e392ab0204961fd1a62c84a222bf5874a9.1284407763.git.matthltc@us.ibm.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Split out the code which searches for non-exiting tasks into its own
helper. Creating this helper not only makes the code slightly more
readable it prepares to move the search out of find_get_context() in
a subsequent commit.
Signed-off-by: NMatt Helsley <matthltc@us.ibm.com>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Robin Green <greenrd@greenrd.org>
Cc: Prasad <prasad@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
LKML-Reference: <561205417b450b8a4bf7488374541d64b4690431.1284407762.git.matthltc@us.ibm.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Hardware breakpoints can't be registered within pid namespaces
because tsk->pid is passed rather than the pid in the current
namespace.

(See https://bugzilla.kernel.org/show_bug.cgi?id=17281 )

This is a quick fix demonstrating the problem but is not the
best method of solving the problem since passing pids internally
is not the best way to avoid pid namespace bugs. Subsequent patches
will show a better solution.

Much thanks to Frederic Weisbecker <fweisbec@gmail.com> for doing the
bulk of the work finding this bug.
Signed-off-by: NMatt Helsley <matthltc@us.ibm.com>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Robin Green <greenrd@greenrd.org>
Cc: Prasad <prasad@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
LKML-Reference: <f63454af09fb1915717251570423eb9ddd338340.1284407762.git.matthltc@us.ibm.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

3f6da390 ("perf: Rework and fix the arch CPU-hotplug hooks") introduced
this breakage. sh_pmu_setup() is missing an opening curly brace.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20100913191729.GA6440@console-pimps.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Also fix a few compile errors due to undefined and duplicated
variables.
Signed-off-by: NMichael Cree <mcree@orcon.net.nz>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1284269844-23251-1-git-send-email-mcree@orcon.net.nz>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

In case you boot with the watchdog disabled, i.e., nowatchdog, then,
if you try to disable it via /proc/sys/kernel/watchdog, you get
a kernel crash. The reason is that you are trying to cancel a hrtimer
which has never been initialized.

This patch fixes this by skipping execution of
watchdog_disable_all_cpus() when the watchdog is marked
disabled from boot.
Signed-off-by: NStephane Eranian <eranian@google.com>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <4c8f7a23.cae9d80a.2c11.0bb4@mx.google.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Merge branch 'tip/perf/core' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace into perf/core

The enums for FTRACE_ENABLE_MCOUNT and FTRACE_DISABLE_MCOUNT were
used as commands to ftrace_run_update_code(). But these commands
were used by the old nasty ftrace daemon that has long been slain.

This is a clean up patch to remove the references to these enums
and simplify the code a little.
Reported-by: NWu Zhangjin <wuzhangjin@gmail.com>
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>

When the function graph tracer funcgraph-irq option is zero, disable
tracing in IRQs. This makes the option have two effects.

1) When reading the trace file, do not display the functions that
   happen in interrupt context (when detected)

2) [*new*] When recording a trace, skip those that are detected
   to be in interrupt by the 'in_irq()' function

Note, in_irq() is updated at irq_enter() and irq_exit(). There are
still functions that are recorded by the function graph tracer that
is in interrupt context but outside the irq_enter/exit() routines.
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>

It's handy to be able to disable the irq related output
and not to have to jump over each irq related code, when
you have no interrest in it.

The option is by default enabled, so there's no change to
current behaviour. It affects only the final output, so all
the irq related data stay in the ring buffer.
Signed-off-by: NJiri Olsa <jolsa@redhat.com>
LKML-Reference: <20100907145344.GC1912@jolsa.brq.redhat.com>
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>

If we do:

 # cd /sys/kernel/debug
 # echo 'do_IRQ:traceon schedule:traceon sys_write:traceon' > \
    set_ftrace_filter
 # cat set_ftrace_filter

We get the following output:

 #### all functions enabled ####
 sys_write:traceon:unlimited
 schedule:traceon:unlimited
 do_IRQ:traceon:unlimited

This outputs two lists. One is the fact that all functions are
currently enabled for function tracing, the other has three probed
functions, which happen to have 'traceon' as their commands.

Currently, when reading the first list (functions enabled) the
seq_file code will receive a "NULL" from the t_next() function
causing it to exit early. This makes "read()" from userspace stop
reading the code at this boarder. Although read is allowed to do this,
some (broken) applications might consider this an end of file and
stop early.

This patch adds the start of the second list to t_next() when it
finishes the first list. It is a simple change and gives the
set_ftrace_filter file nicer reading ability.
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>

This patch keeps track of the index within the elements of
set_ftrace_filter and if the position goes backwards, it nicely
resets and starts from the beginning again.

This allows for lseek and pread to work properly now.
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>

The set_ftrace_filter uses seq_file and reads from two lists. The
pointer returned by t_next() can either be of type struct dyn_ftrace
or struct ftrace_func_probe. If there is a bug (there was one)
the wrong pointer may be used and the reference can cause an oops.

This patch makes t_next() and friends only return the iterator structure
which now has a pointer of type struct dyn_ftrace and struct
ftrace_func_probe. The t_show() can now test if the pointer is NULL or
not and if the pointer exists, it is guaranteed to be of the correct type.

Now if there's a bug, only wrong data will be shown but not an oops.

Cc: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>

After the filtered functions are read, the probed functions are read
from the hash in set_ftrace_filter. When the hashed probed functions
are read, the *pos passed in is reset. Instead of modifying the pos
given to the read function, just record the pos where the filtered
functions ended and subtract from that.
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>

* 'sched/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  sched: Improve latencies under load by decreasing minimum scheduling granularity

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k:
  m68k,m68knommu: Wire up fanotify_init, fanotify_mark, and prlimit64

* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6:
  [IA64] fix siglock

Quoth Tony:

 "I committed the fix for this last week prior to your -rc4 announcement
  reminding us to give proper "Reported-by:" credit.  This one should have
  had:
Reported-by: NTony Ernst <tee@sgi.com>

  and also
Much-useful-investigation-and-tracing-by: NHedi Berriche <hedi@sgi.com>
  Much-useful-investigation-and-tracing-by: Petr Tesarik <ptesarik@novell.com>"

* git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6:
  cifs: prevent possible memory corruption in cifs_demultiplex_thread
  cifs: eliminate some more premature cifsd exits
  cifs: prevent cifsd from exiting prematurely
  [CIFS] ntlmv2/ntlmssp remove-unused-function CalcNTLMv2_partial_mac_key
  cifs: eliminate redundant xdev check in cifs_rename
  Revert "[CIFS] Fix ntlmv2 auth with ntlmssp"
  Revert "missing changes during ntlmv2/ntlmssp auth and sign"
  Revert "Eliminate sparse warning - bad constant expression"
  Revert "[CIFS] Eliminate unused variable warning"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs:
  fs/9p: Don't use dotl version of mknod for dotu inode operations
  fs/9p: Use the correct dentry operations
  9p: Check for NULL fid in v9fs_dir_release()
  fs/9p: Fix error handling in v9fs_get_sb
  fs/9p, net/9p: memory leak fixes

* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs-2.6:
  dquot: do full inode dirty in allocating space

* 'next-spi' of git://git.secretlab.ca/git/linux-2.6:
  spi/pl022: move probe call to subsys_initcall()
  powerpc/5200: mpc52xx_uart.c: Add of_node_put to avoid memory leak
  spi/pl022: fix APB pclk power regression on U300
  spi/spi_s3c64xx: Warn if PIO transfers time out
  spi/s3c64xx: Fix incorrect reuse of 'val' local variable.
  spi/s3c64xx: Fix compilation warning
  spi/dw_spi: clean the cs_control code
  spi/dw_spi: Allow interrupt sharing
  spi/spi_s3c64xx: Increase dead reckoning time in wait_for_xfer()
  spi/spi_s3c64xx: Move to subsys_initcall()
  spi: free children in spi_unregister_master, not siblings
  gpiolib: Add 'struct gpio_chip' forward declaration for !GPIOLIB case
  of: Fix missing includes - ll_temac
  spi/spi_s3c64xx: Staticise non-exported functions
  spi/spi_s3c64xx: Make probe more robust against missing board config

Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Acked-by: NGreg Ungerer <gerg@uclinux.org>

Mathieu reported bad latencies with make -j10 kind of kbuild
workloads - which is mostly caused by us scheduling with a
too coarse granularity.

Reduce the minimum granularity some more, to make sure we
can meet the latency target.

I got the following results (make -j10 kbuild load, average of 3
runs):

 vanilla:

  maximum latency: 38278.9 µs
  average latency:  7730.1 µs

 patched:

  maximum latency: 22702.1 µs
  average latency:  6684.8 µs

Mathieu also measured it:

|
| * wakeup-latency.c (SIGEV_THREAD) with make -j10
|
| - Mainline 2.6.35.2 kernel
|
| maximum latency: 45762.1 µs
| average latency: 7348.6 µs
|
| - With only Peter's smaller min_gran (shown below):
|
| maximum latency: 29100.6 µs
| average latency: 6684.1 µs
|
Reported-by: NMathieu Desnoyers <mathieu.desnoyers@efficios.com>
Reported-by: NLinus Torvalds <torvalds@linux-foundation.org>
Acked-by: NMathieu Desnoyers <mathieu.desnoyers@efficios.com>
Suggested-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <AANLkTi=8m4g01wZPacySoF7U0PevTNVgJoZZrHiUD-pN@mail.gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>