]> err.no Git - linux-2.6/log
linux-2.6
16 years agoftrace: add TRACE_STACK and TRACE_SPECIAL to selftest validation
Steven Rostedt [Mon, 12 May 2008 19:20:54 +0000 (21:20 +0200)]
ftrace: add TRACE_STACK and TRACE_SPECIAL to selftest validation

The selftest validation code checks for valid entries in the trace buffer.
TRACE_STACK and TRACE_SPECIAL have been added to the code but not to
the validator. This patch adds the two to prevent them from flagging a
failure in the selftest.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: printk and trace irqsoff and wakeups
Steven Rostedt [Mon, 12 May 2008 19:20:54 +0000 (21:20 +0200)]
ftrace: printk and trace irqsoff and wakeups

printk called from wakeup critical timings and irqs off can
cause deadlocks since printk might do a wakeup itself. If the
call to printk happens with the runqueue lock held, it can
deadlock.

This patch protects the printk from being called in trace irqs off
with a test to see if the runqueue for the current CPU is locked.
If it is locked, the printk is skipped.

The wakeup always holds the runqueue lock, so the printk is
simply removed.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: remove wakeup from function trace
Steven Rostedt [Mon, 12 May 2008 19:20:54 +0000 (21:20 +0200)]
ftrace: remove wakeup from function trace

trace_function is called by mcount and calling wake_up from that
can have unpredictable results. This patch removes the wakeup from
trace_function.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: make it more available in the Kconfig
Ingo Molnar [Mon, 12 May 2008 19:20:54 +0000 (21:20 +0200)]
ftrace: make it more available in the Kconfig

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: fix wakeup callback
Peter Zijlstra [Mon, 12 May 2008 19:20:53 +0000 (21:20 +0200)]
ftrace: fix wakeup callback

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: trace next state
Peter Zijlstra [Mon, 12 May 2008 19:20:53 +0000 (21:20 +0200)]
ftrace: trace next state

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: sched special
Ingo Molnar [Mon, 12 May 2008 19:20:53 +0000 (21:20 +0200)]
ftrace: sched special

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: sched tree fix
Ingo Molnar [Mon, 12 May 2008 19:20:53 +0000 (21:20 +0200)]
ftrace: sched tree fix

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: include cpu in stacktrace
Ingo Molnar [Mon, 12 May 2008 19:20:53 +0000 (21:20 +0200)]
ftrace: include cpu in stacktrace

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: iter ctrl fix
Ingo Molnar [Mon, 12 May 2008 19:20:53 +0000 (21:20 +0200)]
ftrace: iter ctrl fix

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: fix cmdline tracing
Ingo Molnar [Mon, 12 May 2008 19:20:53 +0000 (21:20 +0200)]
ftrace: fix cmdline tracing

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: make use of tracing_cpumask
Ingo Molnar [Mon, 12 May 2008 19:20:52 +0000 (21:20 +0200)]
ftrace: make use of tracing_cpumask

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: add tracing_cpumask
Ingo Molnar [Mon, 12 May 2008 19:20:52 +0000 (21:20 +0200)]
ftrace: add tracing_cpumask

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: trace scheduler rbtree
Ingo Molnar [Mon, 12 May 2008 19:20:52 +0000 (21:20 +0200)]
ftrace: trace scheduler rbtree

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: fix __trace_special()
Ingo Molnar [Mon, 12 May 2008 19:20:52 +0000 (21:20 +0200)]
ftrace: fix __trace_special()

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: fix wakeups
Ingo Molnar [Mon, 12 May 2008 19:20:52 +0000 (21:20 +0200)]
ftrace: fix wakeups

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: trace curr/next tasks
Ingo Molnar [Mon, 12 May 2008 19:20:52 +0000 (21:20 +0200)]
ftrace: trace curr/next tasks

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: sched tracer, trace full rbtree
Ingo Molnar [Mon, 12 May 2008 19:20:52 +0000 (21:20 +0200)]
ftrace: sched tracer, trace full rbtree

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: make nostacktrace the default
Ingo Molnar [Mon, 12 May 2008 19:20:51 +0000 (21:20 +0200)]
ftrace: make nostacktrace the default

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: sched tracer fix
Ingo Molnar [Mon, 12 May 2008 19:20:51 +0000 (21:20 +0200)]
ftrace: sched tracer fix

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: add stack tracing
Ingo Molnar [Mon, 12 May 2008 19:20:51 +0000 (21:20 +0200)]
ftrace: add stack tracing

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: add wakeup events to sched tracer
Ingo Molnar [Mon, 12 May 2008 19:20:51 +0000 (21:20 +0200)]
ftrace: add wakeup events to sched tracer

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: remove notrace
Ingo Molnar [Mon, 12 May 2008 19:20:51 +0000 (21:20 +0200)]
ftrace: remove notrace

now that we have a kbuild method for notrace, no need to pollute the
C code with the annotations.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: disable -pg for the tracer itself
Ingo Molnar [Mon, 12 May 2008 19:20:51 +0000 (21:20 +0200)]
ftrace: disable -pg for the tracer itself

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: do not profile lib/string.o
Steven Rostedt [Mon, 12 May 2008 19:20:50 +0000 (21:20 +0200)]
ftrace: do not profile lib/string.o

Most archs define the string and memory compare functions in assembly.
Some do not. But these functions may be used in some archs at early
boot up.

Since most archs define this code in assembly and they are not usually
traced, there's no need to trace them when they are not defined in
assembly.

This patch removes the -pg from the CFLAGS for lib/string.o.
This prevents the string functions use in either vdso or early bootup
from crashing the system.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: remove address of function names
Steven Rostedt [Mon, 12 May 2008 19:20:50 +0000 (21:20 +0200)]
ftrace: remove address of function names

PowerPC is very fragile when it comes to use of function names
and function addresses.  ftrace needs to either use all function
addresses or function names (i.e. my_func as suppose to &my_func).

This patch chooses to use the names and not the addresses, and
makes ftrace consistent.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: cleanups
Ingo Molnar [Mon, 12 May 2008 19:20:50 +0000 (21:20 +0200)]
ftrace: cleanups

clean up recent code.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: add trace_function api for other tracers to use
Steven Rostedt [Mon, 12 May 2008 19:20:49 +0000 (21:20 +0200)]
ftrace: add trace_function api for other tracers to use

A new check was added in the ftrace function that wont trace if the CPU
trace buffer is disabled.  Unfortunately, other tracers used ftrace() to
write to the buffer after they disabled it. The new disable check makes
these calls into a nop.

This patch changes the __ftrace that is called without the check into a
new api for the other tracers to use, called "trace_function". The other
tracers use this interface instead when the trace CPU buffer is already
disabled.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: allow the event pipe to be polled
Soeren Sandmann Pedersen [Mon, 12 May 2008 19:20:49 +0000 (21:20 +0200)]
ftrace: allow the event pipe to be polled

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: build fix
Ingo Molnar [Mon, 12 May 2008 19:20:49 +0000 (21:20 +0200)]
ftrace: build fix

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: build fix
Ingo Molnar [Mon, 12 May 2008 19:20:49 +0000 (21:20 +0200)]
ftrace: build fix

no need to backmerge, only affects ftrace-enabled kernels. (which is
not the default)

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: introduce the "hex" output method
Ingo Molnar [Mon, 12 May 2008 19:20:49 +0000 (21:20 +0200)]
ftrace: introduce the "hex" output method

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: build fix
Ingo Molnar [Mon, 12 May 2008 19:20:49 +0000 (21:20 +0200)]
ftrace: build fix

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: use cpu clock again
Ingo Molnar [Mon, 12 May 2008 19:20:48 +0000 (21:20 +0200)]
ftrace: use cpu clock again

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: enabled tracing by default
Steven Rostedt [Mon, 12 May 2008 19:20:48 +0000 (21:20 +0200)]
ftrace: enabled tracing by default

This patch is the correct way to have tracing enabled by default.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: disable tracing on failure
Steven Rostedt [Mon, 12 May 2008 19:20:48 +0000 (21:20 +0200)]
ftrace: disable tracing on failure

Since ftrace touches practically every function. If we detect any
anomaly, we want to fully disable ftrace. This patch adds code
to try shutdown ftrace as much as possible without doing any more
harm is something is detected not quite correct.

This only kills ftrace, this patch does have checks for other parts of
the tracer (irqsoff, wakeup, etc.).

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace - fix dynamic ftrace memory leak
Steven Rostedt [Mon, 12 May 2008 19:20:48 +0000 (21:20 +0200)]
ftrace - fix dynamic ftrace memory leak

The ftrace dynamic function update allocates a record to store the
instruction pointers that are being modified. If the modified
instruction pointer fails to update, then the record is marked as
failed and nothing more is done.

Worse, if the modification fails, but the record ip function is still
called, it will allocate a new record and try again. In just a matter
of time, will this cause a serious memory leak and crash the system.

This patch plugs this memory leak. When a record fails, it is
included back into the pool of records to be used. Now a record may
fail over and over again, but the number of allocated records will
not increase.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: pipe fixes
Steven Rostedt [Mon, 12 May 2008 19:20:48 +0000 (21:20 +0200)]
ftrace: pipe fixes

Some fixes for better output with the trace pipe.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace, locking fix
Ingo Molnar [Mon, 12 May 2008 19:20:48 +0000 (21:20 +0200)]
ftrace, locking fix

should be an irq-safe lock ...

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: add trace_special()
Ingo Molnar [Mon, 12 May 2008 19:20:47 +0000 (21:20 +0200)]
ftrace: add trace_special()

for ad-hoc tracing.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: bin-output
Ingo Molnar [Mon, 12 May 2008 19:20:47 +0000 (21:20 +0200)]
ftrace: bin-output

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: add raw output
Ingo Molnar [Mon, 12 May 2008 19:20:47 +0000 (21:20 +0200)]
ftrace: add raw output

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: clean-up-pipe-iteration
Ingo Molnar [Mon, 12 May 2008 19:20:46 +0000 (21:20 +0200)]
ftrace: clean-up-pipe-iteration

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: remove-idx-sync
Ingo Molnar [Mon, 12 May 2008 19:20:46 +0000 (21:20 +0200)]
ftrace: remove-idx-sync

remove idx syncing - it's expensive on SMP.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: fast, scalable, synchronized timestamps
Ingo Molnar [Mon, 12 May 2008 19:20:46 +0000 (21:20 +0200)]
ftrace: fast, scalable, synchronized timestamps

implement globally synchronized, fast and scalable time source for tracing.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: timestamp syncing, prepare
Ingo Molnar [Mon, 12 May 2008 19:20:46 +0000 (21:20 +0200)]
ftrace: timestamp syncing, prepare

rename and uninline now() to ftrace_now().

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: cleanups
Ingo Molnar [Mon, 12 May 2008 19:20:46 +0000 (21:20 +0200)]
ftrace: cleanups

no code changed.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: fix locking
Ingo Molnar [Mon, 12 May 2008 19:20:46 +0000 (21:20 +0200)]
ftrace: fix locking

we can hold all cpu trace buffer locks at once - put each into a
separate lock class.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: user run time file reading
Steven Rostedt [Mon, 12 May 2008 19:20:46 +0000 (21:20 +0200)]
ftrace: user run time file reading

This patch creates a file called trace_pipe in the tracing
debug directory. This file is a consumer of the trace buffers.
This means that reads of this file consumes the entries from
the trace buffers so that they will not be read a second time,
as contrast to the static buffers latency_trace and trace.

Reading from the trace_pipe will remove the entries from trace
and latency_trace too.

The advantage that trace_pipe has is that it can record live
traces. It will block when there is nothing in the buffer,
and read the entries as they are entered.  An EOF happens when
tracing is disabled (tracing_enabled = 0).

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: add a buffer for output
Steven Rostedt [Mon, 12 May 2008 19:20:46 +0000 (21:20 +0200)]
ftrace: add a buffer for output

Later patches will need to print the same things as the seq output
does. But those outputs will not use the seq utility. This patch
adds a buffer to the iterator, that can be used by either the
seq utility or other output.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: change buffers to producer consumer
Steven Rostedt [Mon, 12 May 2008 19:20:45 +0000 (21:20 +0200)]
ftrace: change buffers to producer consumer

This patch changes the way the CPU trace buffers are handled.
Instead of always starting from the trace page head, the logic
is changed to a producer consumer logic. This allows for the
buffers to be drained while they are alive.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: reset selftests
Steven Rostedt [Mon, 12 May 2008 19:20:45 +0000 (21:20 +0200)]
ftrace: reset selftests

The tests may leave stuff in the buffers. This resets the buffers
after each test is run. If a test fails, it does not reset the
buffer to avoid touching a buffer that is corrupted.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: disable all tracers on corrupted buffer
Steven Rostedt [Mon, 12 May 2008 19:20:45 +0000 (21:20 +0200)]
ftrace: disable all tracers on corrupted buffer

If the trace buffer is detected to be corrupted, then we
disable all tracers.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: fix time offset
Ingo Molnar [Mon, 12 May 2008 19:20:45 +0000 (21:20 +0200)]
ftrace: fix time offset

fix time offset calculations and ordering, plus make code more consistent.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: startup tester on dynamic tracing.
Steven Rostedt [Mon, 12 May 2008 19:20:45 +0000 (21:20 +0200)]
ftrace: startup tester on dynamic tracing.

This patch adds a startup self test on dynamic code modification
and filters. The test filters on a specific function, makes sure that
no other function is traced, exectutes the function, then makes sure that
the function is traced.

This patch also fixes a slight bug with the ftrace selftest, where
tracer_enabled was not being set.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: add README
Ingo Molnar [Mon, 12 May 2008 19:20:45 +0000 (21:20 +0200)]
ftrace: add README

make it easier for newbies to find their way around.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: cleanups
Ingo Molnar [Mon, 12 May 2008 19:20:45 +0000 (21:20 +0200)]
ftrace: cleanups

factor out code and clean it up.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: add self-tests
Steven Rostedt [Mon, 12 May 2008 19:20:44 +0000 (21:20 +0200)]
ftrace: add self-tests

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: force recording
Steven Rostedt [Mon, 12 May 2008 19:20:44 +0000 (21:20 +0200)]
ftrace: force recording

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: fix max latency
Steven Rostedt [Mon, 12 May 2008 19:20:44 +0000 (21:20 +0200)]
ftrace: fix max latency

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: fix updates to max trace
Steven Rostedt [Mon, 12 May 2008 19:20:44 +0000 (21:20 +0200)]
ftrace: fix updates to max trace

This patch fixes some bugs to the updating of the max trace that
was caused by implementing the new buffering.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: don't use raw_local_irq_save/restore
Steven Rostedt [Mon, 12 May 2008 19:20:44 +0000 (21:20 +0200)]
ftrace: don't use raw_local_irq_save/restore

Using raw_local_irq_save/restore confuses lockdep.
It's fine to use the normal ones.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: lockdep notrace annotations
Steven Rostedt [Mon, 12 May 2008 19:20:44 +0000 (21:20 +0200)]
ftrace: lockdep notrace annotations

Add notrace annotations to lockdep to keep ftrace from causing
recursive problems with lock tracing and debugging.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: irqs off smp_processor_id() fix
Steven Rostedt [Mon, 12 May 2008 19:20:44 +0000 (21:20 +0200)]
ftrace: irqs off smp_processor_id() fix

The irqsoff function tracer did a __get_cpu_var to determine
if it should trace the function or not. The problem is that
__get_cpu_var can preempt between getting the CPU and reading
the cpu variable. This means that the cpu variable that is
being read is not from the cpu being run on.

At worst, this can give a false positive, where we trace the
function when we should not.  It will never give a false negative
since we only want to trace when interrupts are disabled
and we never preempt when they are.

This fix adds a check after reading the irq flags to only
trace if the interrupts are actually disabled. It also changes
the reading of the cpu variable to use a raw_smp_processor_id
since we now don't care if we preempt. We still catch that fact.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: debug smp_processor_id, use notrace preempt disable
Steven Rostedt [Mon, 12 May 2008 19:20:44 +0000 (21:20 +0200)]
ftrace: debug smp_processor_id, use notrace preempt disable

The debug smp_processor_id caused a recursive fault in debugging
the irqsoff tracer. The tracer used a smp_processor_id in the
ftrace callback, and this function called preempt_disable which
also is traced. This caused a recursive fault (stack overload).

Since using smp_processor_id without debugging on does not cause
faults with the tracer (even when the tracer is wrong), the
debug version should not cause a system reboot.

This changes the debug_smp_processor_id to use the notrace versions
of preempt_disable and enable.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: fix kexec
Ingo Molnar [Mon, 12 May 2008 19:20:43 +0000 (21:20 +0200)]
ftrace: fix kexec

disable the tracer while kexec pulls the rug from under the old
kernel.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: convert single large buffer into single pages.
Steven Rostedt [Mon, 12 May 2008 19:20:43 +0000 (21:20 +0200)]
ftrace: convert single large buffer into single pages.

Allocating large buffers for the tracer may fail easily.
This patch converts the buffer from a large ordered allocation
to single pages. It uses the struct page LRU field to link the
pages together.

Later patches may also implement dynamic increasing and decreasing
of the trace buffers.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: add filter select functions to trace
Steven Rostedt [Mon, 12 May 2008 19:20:43 +0000 (21:20 +0200)]
ftrace: add filter select functions to trace

This patch adds two files to the debugfs system:

 /debugfs/tracing/available_filter_functions

and

 /debugfs/tracing/set_ftrace_filter

The available_filter_functions lists all functions that has been
recorded by the ftraced that has called the ftrace_record_ip function.
This is to allow users to see what functions have been converted
to nops and can be enabled for tracing.

To enable functions, simply echo the names (whitespace delimited)
into set_ftrace_filter. Simple wildcards are also allowed.

echo 'scheduler' > /debugfs/tracing/set_ftrace_filter

Will have only the scheduler be activated when tracing is enabled.

echo 'sched_*' > /debugfs/tracing/set_ftrace_filter

Will have only the functions starting with 'sched_' be activated.

echo '*lock' > /debugfs/tracing/set_ftrace_filter

Will have only functions ending with 'lock' be activated.

echo '*lock*' > /debugfs/tracing/set_ftrace_filter

Will have only functions with 'lock' in its name be activated.

Note: 'sched*lock' will not work. The only wildcards that are
allowed is an asterisk and the beginning and or end of the string
passed in.

Multiple names can be passed in with whitespace delimited:

echo 'scheduler *lock *acpi*' > /debugfs/tracing/set_ftrace_filter

is also the same as:

echo 'scheduler' > /debugfs/tracing/set_ftrace_filter
echo '*lock' >> /debugfs/tracing/set_ftrace_filter
echo '*acpi*' >> /debugfs/tracing/set_ftrace_filter

Appending does just that. It appends to the list.

To disable all filters simply echo an empty line in:

echo > /debugfs/tracing/set_ftrace_filter

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: use dynamic patching for updating mcount calls
Steven Rostedt [Mon, 12 May 2008 19:20:43 +0000 (21:20 +0200)]
ftrace: use dynamic patching for updating mcount calls

This patch replaces the indirect call to the mcount function
pointer with a direct call that will be patched by the
dynamic ftrace routines.

On boot up, the mcount function calls the ftace_stub function.
When the dynamic ftrace code is initialized, the ftrace_stub
is replaced with a call to the ftrace_record_ip, which records
the instruction pointers of the locations that call it.

Later, the ftraced daemon will call kstop_machine and patch all
the locations to nops.

When a ftrace is enabled, the original calls to mcount will now
be set top call ftrace_caller, which will do a direct call
to the registered ftrace function. This direct call is also patched
when the function that should be called is updated.

All patching is performed by a kstop_machine routine to prevent any
type of race conditions that is associated with modifying code
on the fly.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: move memory management out of arch code
Steven Rostedt [Mon, 12 May 2008 19:20:43 +0000 (21:20 +0200)]
ftrace: move memory management out of arch code

This patch moves the memory management of the ftrace
records out of the arch code and into the generic code
making the arch code simpler.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: use nops instead of jmp
Steven Rostedt [Mon, 12 May 2008 19:20:43 +0000 (21:20 +0200)]
ftrace: use nops instead of jmp

This patch patches the call to mcount with nops instead
of a jmp over the mcount call.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: add ftrace_enabled sysctl to disable mcount function
Steven Rostedt [Mon, 12 May 2008 19:20:43 +0000 (21:20 +0200)]
ftrace: add ftrace_enabled sysctl to disable mcount function

This patch adds back the sysctl ftrace_enabled. This time it is
defaulted to on, if DYNAMIC_FTRACE is configured. When ftrace_enabled
is disabled, the ftrace function is set to the stub return.

If DYNAMIC_FTRACE is also configured, on ftrace_enabled = 0,
the registered ftrace functions will all be set to jmps, but no more
new calls to ftrace recording (used to find the ftrace calling sites)
will be called.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: dynamic enabling/disabling of function calls
Steven Rostedt [Mon, 12 May 2008 19:20:42 +0000 (21:20 +0200)]
ftrace: dynamic enabling/disabling of function calls

This patch adds a feature to dynamically replace the ftrace code
with the jmps to allow a kernel with ftrace configured to run
as fast as it can without it configured.

The way this works, is on bootup (if ftrace is enabled), a ftrace
function is registered to record the instruction pointer of all
places that call the function.

Later, if there's still any code to patch, a kthread is awoken
(rate limited to at most once a second) that performs a stop_machine,
and replaces all the code that was called with a jmp over the call
to ftrace. It only replaces what was found the previous time. Typically
the system reaches equilibrium quickly after bootup and there's no code
patching needed at all.

e.g.

  call ftrace  /* 5 bytes */

is replaced with

  jmp 3f  /* jmp is 2 bytes and we jump 3 forward */
3:

When we want to enable ftrace for function tracing, the IP recording
is removed, and stop_machine is called again to replace all the locations
of that were recorded back to the call of ftrace.  When it is disabled,
we replace the code back to the jmp.

Allocation is done by the kthread. If the ftrace recording function is
called, and we don't have any record slots available, then we simply
skip that call. Once a second a new page (if needed) is allocated for
recording new ftrace function calls.  A large batch is allocated at
boot up to get most of the calls there.

Because we do this via stop_machine, we don't have to worry about another
CPU executing a ftrace call as we modify it. But we do need to worry
about NMI's so all functions that might be called via nmi must be
annotated with notrace_nmi. When this code is configured in, the NMI code
will not call notrace.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: trace preempt off critical timings
Steven Rostedt [Mon, 12 May 2008 19:20:42 +0000 (21:20 +0200)]
ftrace: trace preempt off critical timings

Add preempt off timings. A lot of kernel core code is taken from the RT patch
latency trace that was written by Ingo Molnar.

This adds "preemptoff" and "preemptirqsoff" to /debugfs/tracing/available_tracers

Now instead of just tracing irqs off, preemption off can be selected
to be recorded.

When this is selected, it shares the same files as irqs off timings.
One can either trace preemption off, irqs off, or one or the other off.

By echoing "preemptoff" into /debugfs/tracing/current_tracer, recording
of preempt off only is performed. "irqsoff" will only record the time
irqs are disabled, but "preemptirqsoff" will take the total time irqs
or preemption are disabled. Runtime switching of these options is now
supported by simpling echoing in the appropriate trace name into
/debugfs/tracing/current_tracer.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: trace irq disabled critical timings
Steven Rostedt [Mon, 12 May 2008 19:20:42 +0000 (21:20 +0200)]
ftrace: trace irq disabled critical timings

This patch adds latency tracing for critical timings
(how long interrupts are disabled for).

 "irqsoff" is added to /debugfs/tracing/available_tracers

Note:
  tracing_max_latency
    also holds the max latency for irqsoff (in usecs).
   (default to large number so one must start latency tracing)

  tracing_thresh
    threshold (in usecs) to always print out if irqs off
    is detected to be longer than stated here.
    If irq_thresh is non-zero, then max_irq_latency
    is ignored.

Here's an example of a trace with ftrace_enabled = 0

=======
preemption latency trace v1.1.5 on 2.6.24-rc7
Signed-off-by: Ingo Molnar <mingo@elte.hu>
--------------------------------------------------------------------
 latency: 100 us, #3/3, CPU#1 | (M:rt VP:0, KP:0, SP:0 HP:0 #P:2)
    -----------------
    | task: swapper-0 (uid:0 nice:0 policy:0 rt_prio:0)
    -----------------
 => started at: _spin_lock_irqsave+0x2a/0xb7
 => ended at:   _spin_unlock_irqrestore+0x32/0x5f

                 _------=> CPU#
                / _-----=> irqs-off
               | / _----=> need-resched
               || / _---=> hardirq/softirq
               ||| / _--=> preempt-depth
               |||| /
               |||||     delay
   cmd     pid ||||| time  |   caller
      \   /    |||||   \   |   /
 swapper-0     1d.s3    0us+: _spin_lock_irqsave+0x2a/0xb7 (e1000_update_stats+0x47/0x64c [e1000])
 swapper-0     1d.s3  100us : _spin_unlock_irqrestore+0x32/0x5f (e1000_update_stats+0x641/0x64c [e1000])
 swapper-0     1d.s3  100us : trace_hardirqs_on_caller+0x75/0x89 (_spin_unlock_irqrestore+0x32/0x5f)

vim:ft=help
=======

And this is a trace with ftrace_enabled == 1

=======
preemption latency trace v1.1.5 on 2.6.24-rc7
--------------------------------------------------------------------
 latency: 102 us, #12/12, CPU#1 | (M:rt VP:0, KP:0, SP:0 HP:0 #P:2)
    -----------------
    | task: swapper-0 (uid:0 nice:0 policy:0 rt_prio:0)
    -----------------
 => started at: _spin_lock_irqsave+0x2a/0xb7
 => ended at:   _spin_unlock_irqrestore+0x32/0x5f

                 _------=> CPU#
                / _-----=> irqs-off
               | / _----=> need-resched
               || / _---=> hardirq/softirq
               ||| / _--=> preempt-depth
               |||| /
               |||||     delay
   cmd     pid ||||| time  |   caller
      \   /    |||||   \   |   /
 swapper-0     1dNs3    0us+: _spin_lock_irqsave+0x2a/0xb7 (e1000_update_stats+0x47/0x64c [e1000])
 swapper-0     1dNs3   46us : e1000_read_phy_reg+0x16/0x225 [e1000] (e1000_update_stats+0x5e2/0x64c [e1000])
 swapper-0     1dNs3   46us : e1000_swfw_sync_acquire+0x10/0x99 [e1000] (e1000_read_phy_reg+0x49/0x225 [e1000])
 swapper-0     1dNs3   46us : e1000_get_hw_eeprom_semaphore+0x12/0xa6 [e1000] (e1000_swfw_sync_acquire+0x36/0x99 [e1000])
 swapper-0     1dNs3   47us : __const_udelay+0x9/0x47 (e1000_read_phy_reg+0x116/0x225 [e1000])
 swapper-0     1dNs3   47us+: __delay+0x9/0x50 (__const_udelay+0x45/0x47)
 swapper-0     1dNs3   97us : preempt_schedule+0xc/0x84 (__delay+0x4e/0x50)
 swapper-0     1dNs3   98us : e1000_swfw_sync_release+0xc/0x55 [e1000] (e1000_read_phy_reg+0x211/0x225 [e1000])
 swapper-0     1dNs3   99us+: e1000_put_hw_eeprom_semaphore+0x9/0x35 [e1000] (e1000_swfw_sync_release+0x50/0x55 [e1000])
 swapper-0     1dNs3  101us : _spin_unlock_irqrestore+0xe/0x5f (e1000_update_stats+0x641/0x64c [e1000])
 swapper-0     1dNs3  102us : _spin_unlock_irqrestore+0x32/0x5f (e1000_update_stats+0x641/0x64c [e1000])
 swapper-0     1dNs3  102us : trace_hardirqs_on_caller+0x75/0x89 (_spin_unlock_irqrestore+0x32/0x5f)

vim:ft=help
=======

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: tracer for scheduler wakeup latency
Steven Rostedt [Mon, 12 May 2008 19:20:42 +0000 (21:20 +0200)]
ftrace: tracer for scheduler wakeup latency

This patch adds the tracer that tracks the wakeup latency of the
highest priority waking task.

  "wakeup" is added to /debugfs/tracing/available_tracers

Also added to /debugfs/tracing

  tracing_max_latency
     holds the current max latency for the wakeup

  wakeup_thresh
     if set to other than zero, a log will be recorded
     for every wakeup that takes longer than the number
     entered in here (usecs for all counters)
     (deletes previous trace)

Examples:

  (with ftrace_enabled = 0)

============
preemption latency trace v1.1.5 on 2.6.24-rc8
Signed-off-by: Ingo Molnar <mingo@elte.hu>
--------------------------------------------------------------------
 latency: 26 us, #2/2, CPU#1 | (M:rt VP:0, KP:0, SP:0 HP:0 #P:2)
    -----------------
    | task: migration/0-3 (uid:0 nice:-5 policy:1 rt_prio:99)
    -----------------

                 _------=> CPU#
                / _-----=> irqs-off
               | / _----=> need-resched
               || / _---=> hardirq/softirq
               ||| / _--=> preempt-depth
               |||| /
               |||||     delay
   cmd     pid ||||| time  |   caller
      \   /    |||||   \   |   /
   quilt-8551  0d..3    0us+: wake_up_process+0x15/0x17 <ffffffff80233e80> (sched_exec+0xc9/0x100 <ffffffff80235343>)
   quilt-8551  0d..4   26us : sched_switch_callback+0x73/0x81 <ffffffff80338d2f> (schedule+0x483/0x6d5 <ffffffff8048b3ee>)

vim:ft=help
============

  (with ftrace_enabled = 1)

============
preemption latency trace v1.1.5 on 2.6.24-rc8
--------------------------------------------------------------------
 latency: 36 us, #45/45, CPU#0 | (M:rt VP:0, KP:0, SP:0 HP:0 #P:2)
    -----------------
    | task: migration/1-5 (uid:0 nice:-5 policy:1 rt_prio:99)
    -----------------

                 _------=> CPU#
                / _-----=> irqs-off
               | / _----=> need-resched
               || / _---=> hardirq/softirq
               ||| / _--=> preempt-depth
               |||| /
               |||||     delay
   cmd     pid ||||| time  |   caller
      \   /    |||||   \   |   /
    bash-10653 1d..3    0us : wake_up_process+0x15/0x17 <ffffffff80233e80> (sched_exec+0xc9/0x100 <ffffffff80235343>)
    bash-10653 1d..3    1us : try_to_wake_up+0x271/0x2e7 <ffffffff80233dcf> (sub_preempt_count+0xc/0x7a <ffffffff8023309e>)
    bash-10653 1d..2    2us : try_to_wake_up+0x296/0x2e7 <ffffffff80233df4> (update_rq_clock+0x9/0x20 <ffffffff802303f3>)
    bash-10653 1d..2    2us : update_rq_clock+0x1e/0x20 <ffffffff80230408> (__update_rq_clock+0xc/0x90 <ffffffff80230366>)
    bash-10653 1d..2    3us : __update_rq_clock+0x1b/0x90 <ffffffff80230375> (sched_clock+0x9/0x29 <ffffffff80214529>)
    bash-10653 1d..2    4us : try_to_wake_up+0x2a6/0x2e7 <ffffffff80233e04> (activate_task+0xc/0x3f <ffffffff8022ffca>)
    bash-10653 1d..2    4us : activate_task+0x2d/0x3f <ffffffff8022ffeb> (enqueue_task+0xe/0x66 <ffffffff8022ff66>)
    bash-10653 1d..2    5us : enqueue_task+0x5b/0x66 <ffffffff8022ffb3> (enqueue_task_rt+0x9/0x3c <ffffffff80233351>)
    bash-10653 1d..2    6us : try_to_wake_up+0x2ba/0x2e7 <ffffffff80233e18> (check_preempt_wakeup+0x12/0x99 <ffffffff80234f84>)
[...]
    bash-10653 1d..5   33us : tracing_record_cmdline+0xcf/0xd4 <ffffffff80338aad> (_spin_unlock+0x9/0x33 <ffffffff8048d3ec>)
    bash-10653 1d..5   34us : _spin_unlock+0x19/0x33 <ffffffff8048d3fc> (sub_preempt_count+0xc/0x7a <ffffffff8023309e>)
    bash-10653 1d..4   35us : wakeup_sched_switch+0x65/0x2ff <ffffffff80339f66> (_spin_lock_irqsave+0xc/0xa9 <ffffffff8048d08b>)
    bash-10653 1d..4   35us : _spin_lock_irqsave+0x19/0xa9 <ffffffff8048d098> (add_preempt_count+0xe/0x77 <ffffffff8023311a>)
    bash-10653 1d..4   36us : sched_switch_callback+0x73/0x81 <ffffffff80338d2f> (schedule+0x483/0x6d5 <ffffffff8048b3ee>)

vim:ft=help
============

The [...] was added here to not waste your email box space.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: add tracing of context switches
Steven Rostedt [Mon, 12 May 2008 19:20:42 +0000 (21:20 +0200)]
ftrace: add tracing of context switches

This patch adds context switch tracing, of the format of:

                  _------=> CPU#
                 / _-----=> irqs-off
                | / _----=> need-resched
                || / _---=> hardirq/softirq
                ||| / _--=> preempt-depth
                |||| /
                |||||     delay
    cmd     pid ||||| time  |      pid:prio:state
       \   /    |||||   \   |      /
  swapper-0     1d..3    137us+:  0:140:R --> 2912:120
     sshd-2912  1d..3    216us+:  2912:120:S --> 0:140
  swapper-0     1d..3    261us+:  0:140:R --> 2912:120
     bash-2920  0d..3    267us+:  2920:120:S --> 0:140
     sshd-2912  1d..3    330us!:  2912:120:S --> 0:140
  swapper-0     1d..3   2389us+:  0:140:R --> 2847:120
 yum-upda-2847  1d..3   2411us!:  2847:120:S --> 0:140
  swapper-0     0d..3  11089us+:  0:140:R --> 3139:120
 gdm-bina-3139  0d..3  11113us!:  3139:120:S --> 0:140
  swapper-0     1d..3 102328us+:  0:140:R --> 2847:120
 yum-upda-2847  1d..3 102348us!:  2847:120:S --> 0:140

 "sched_switch" is added to /debugfs/tracing/available_tracers

[ Eugene Teo <eugeneteo@kernel.sg: remove unused tracing_sched_switch_enabled ]

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: function tracer
Steven Rostedt [Mon, 12 May 2008 19:20:42 +0000 (21:20 +0200)]
ftrace: function tracer

This is a simple trace that uses the ftrace infrastructure. It is
designed to be fast and small, and easy to use. It is useful to
record things that happen over a very short period of time, and
not to analyze the system in general.

 Updates:

  available_tracers
     "function" is added to this file.

  current_tracer
    To enable the function tracer:

      echo function > /debugfs/tracing/current_tracer

     To disable the tracer:

       echo disable > /debugfs/tracing/current_tracer

The output of the function_trace file is as follows

  "echo noverbose > /debugfs/tracing/iter_ctrl"

preemption latency trace v1.1.5 on 2.6.24-rc7-tst
Signed-off-by: Ingo Molnar <mingo@elte.hu>
--------------------------------------------------------------------
 latency: 0 us, #419428/4361791, CPU#1 | (M:desktop VP:0, KP:0, SP:0 HP:0 #P:4)
    -----------------
    | task: -0 (uid:0 nice:0 policy:0 rt_prio:0)
    -----------------

                 _------=> CPU#
                / _-----=> irqs-off
               | / _----=> need-resched
               || / _---=> hardirq/softirq
               ||| / _--=> preempt-depth
               |||| /
               |||||     delay
   cmd     pid ||||| time  |   caller
      \   /    |||||   \   |   /
 swapper-0     0d.h. 1595128us+: set_normalized_timespec+0x8/0x2d <c043841d> (ktime_get_ts+0x4a/0x4e <c04499d4>)
 swapper-0     0d.h. 1595131us+: _spin_lock+0x8/0x18 <c0630690> (hrtimer_interrupt+0x6e/0x1b0 <c0449c56>)

Or with verbose turned on:

  "echo verbose > /debugfs/tracing/iter_ctrl"

preemption latency trace v1.1.5 on 2.6.24-rc7-tst
--------------------------------------------------------------------
 latency: 0 us, #419428/4361791, CPU#1 | (M:desktop VP:0, KP:0, SP:0 HP:0 #P:4)
    -----------------
    | task: -0 (uid:0 nice:0 policy:0 rt_prio:0)
    -----------------

         swapper     0 0 9 00000000 00000000 [f3675f41] 1595.128ms (+0.003ms): set_normalized_timespec+0x8/0x2d <c043841d> (ktime_get_ts+0x4a/0x4e <c04499d4>)
         swapper     0 0 9 00000000 00000001 [f3675f45] 1595.131ms (+0.003ms): _spin_lock+0x8/0x18 <c0630690> (hrtimer_interrupt+0x6e/0x1b0 <c0449c56>)
         swapper     0 0 9 00000000 00000002 [f3675f48] 1595.135ms (+0.003ms): _spin_lock+0x8/0x18 <c0630690> (hrtimer_interrupt+0x6e/0x1b0 <c0449c56>)

The "trace" file is not affected by the verbose mode, but is by the symonly.

 echo "nosymonly" > /debugfs/tracing/iter_ctrl

tracer:
[   81.479967] CPU 0: bash:3154 register_ftrace_function+0x5f/0x66 <ffffffff80337a4d> <-- _spin_unlock_irqrestore+0xe/0x5a <ffffffff8048cc8f>
[   81.479967] CPU 0: bash:3154 _spin_unlock_irqrestore+0x3e/0x5a <ffffffff8048ccbf> <-- sub_preempt_count+0xc/0x7a <ffffffff80233d7b>
[   81.479968] CPU 0: bash:3154 sub_preempt_count+0x30/0x7a <ffffffff80233d9f> <-- in_lock_functions+0x9/0x24 <ffffffff8025a75d>
[   81.479968] CPU 0: bash:3154 vfs_write+0x11d/0x155 <ffffffff8029a043> <-- dnotify_parent+0x12/0x78 <ffffffff802d54fb>
[   81.479968] CPU 0: bash:3154 dnotify_parent+0x2d/0x78 <ffffffff802d5516> <-- _spin_lock+0xe/0x70 <ffffffff8048c910>
[   81.479969] CPU 0: bash:3154 _spin_lock+0x1b/0x70 <ffffffff8048c91d> <-- add_preempt_count+0xe/0x77 <ffffffff80233df7>
[   81.479969] CPU 0: bash:3154 add_preempt_count+0x3e/0x77 <ffffffff80233e27> <-- in_lock_functions+0x9/0x24 <ffffffff8025a75d>

 echo "symonly" > /debugfs/tracing/iter_ctrl

tracer:
[   81.479913] CPU 0: bash:3154 register_ftrace_function+0x5f/0x66 <-- _spin_unlock_irqrestore+0xe/0x5a
[   81.479913] CPU 0: bash:3154 _spin_unlock_irqrestore+0x3e/0x5a <-- sub_preempt_count+0xc/0x7a
[   81.479913] CPU 0: bash:3154 sub_preempt_count+0x30/0x7a <-- in_lock_functions+0x9/0x24
[   81.479914] CPU 0: bash:3154 vfs_write+0x11d/0x155 <-- dnotify_parent+0x12/0x78
[   81.479914] CPU 0: bash:3154 dnotify_parent+0x2d/0x78 <-- _spin_lock+0xe/0x70
[   81.479914] CPU 0: bash:3154 _spin_lock+0x1b/0x70 <-- add_preempt_count+0xe/0x77
[   81.479914] CPU 0: bash:3154 add_preempt_count+0x3e/0x77 <-- in_lock_functions+0x9/0x24

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: latency tracer infrastructure
Steven Rostedt [Mon, 12 May 2008 19:20:42 +0000 (21:20 +0200)]
ftrace: latency tracer infrastructure

This patch adds the latency tracer infrastructure. This patch
does not add anything that will select and turn it on, but will
be used by later patches.

If it were to be compiled, it would add the following files
to the debugfs:

 The root tracing directory:

  /debugfs/tracing/

This patch also adds the following files:

  available_tracers
     list of available tracers. Currently no tracers are
     available. Looking into this file only shows
     "none" which is used to unregister all tracers.

  current_tracer
     The trace that is currently active. Empty on start up.
     To switch to a tracer simply echo one of the tracers that
     are listed in available_tracers:

   example: (used with later patches)

      echo function > /debugfs/tracing/current_tracer

     To disable the tracer:

       echo disable > /debugfs/tracing/current_tracer

  tracing_enabled
     echoing "1" into this file starts the ftrace function tracing
      (if sysctl kernel.ftrace_enabled=1)
     echoing "0" turns it off.

  latency_trace
      This file is readonly and holds the result of the trace.

  trace
      This file outputs a easier to read version of the trace.

  iter_ctrl
      Controls the way the output of traces look.
      So far there's two controls:
        echoing in "symonly" will only show the kallsyms variables
            without the addresses (if kallsyms was configured)
        echoing in "verbose" will change the output to show
            a lot more data, but not very easy to understand by
            humans.
        echoing in "nosymonly" turns off symonly.
        echoing in "noverbose" turns off verbose.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: add basic support for gcc profiler instrumentation
Arnaldo Carvalho de Melo [Mon, 12 May 2008 19:20:42 +0000 (21:20 +0200)]
ftrace: add basic support for gcc profiler instrumentation

If CONFIG_FTRACE is selected and /proc/sys/kernel/ftrace_enabled is
set to a non-zero value the ftrace routine will be called everytime
we enter a kernel function that is not marked with the "notrace"
attribute.

The ftrace routine will then call a registered function if a function
happens to be registered.

[ This code has been highly hacked by Steven Rostedt and Ingo Molnar,
  so don't blame Arnaldo for all of this ;-) ]

Update:
  It is now possible to register more than one ftrace function.
  If only one ftrace function is registered, that will be the
  function that ftrace calls directly. If more than one function
  is registered, then ftrace will call a function that will loop
  through the functions to call.

Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: annotate core code that should not be traced
Arnaldo Carvalho de Melo [Mon, 12 May 2008 19:20:41 +0000 (21:20 +0200)]
ftrace: annotate core code that should not be traced

Mark with "notrace" functions in core code that should not be
traced.  The "notrace" attribute will prevent gcc from adding
a call to ftrace on the annotated funtions.

Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agox86: add notrace annotations to vsyscall.
Steven Rostedt [Mon, 12 May 2008 19:20:41 +0000 (21:20 +0200)]
x86: add notrace annotations to vsyscall.

Add the notrace annotations to the vsyscall functions - there we are
not in kernel context yet, so the tracer function cannot (and must not)
be called.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agotracing: add notrace to linkage.h
Ingo Molnar [Mon, 12 May 2008 19:20:41 +0000 (21:20 +0200)]
tracing: add notrace to linkage.h

notrace signals that a function should not be traced. Most of the
time this is used by tracers to annotate code that cannot be
traced - it's in a volatile state (such as in user vdso context
or NMI context) or it's in the tracer internals.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: add preempt_enable/disable notrace macros
Steven Rostedt [Mon, 12 May 2008 19:20:41 +0000 (21:20 +0200)]
ftrace: add preempt_enable/disable notrace macros

The tracer may need to call preempt_enable and disable functions
for time keeping and such. The trace gets ugly when we see these
functions show up for all traces. To make the output cleaner
this patch adds preempt_enable_notrace and preempt_disable_notrace
to be used by tracer (and debugging) functions.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoftrace: make the task state char-string visible to all
Steven Rostedt [Mon, 12 May 2008 19:20:41 +0000 (21:20 +0200)]
ftrace: make the task state char-string visible to all

The tracer wants to be able to convert the state number
into a user visible character. This patch pulls that conversion
string out the scheduler into the header. This way if it were to
ever change, other parts of the kernel will know.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agosched: add latency tracer callbacks to the scheduler
Ingo Molnar [Mon, 12 May 2008 19:20:41 +0000 (21:20 +0200)]
sched: add latency tracer callbacks to the scheduler

add 3 lightweight callbacks to the tracer backend.

zero impact if tracing is turned off.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
16 years agoMerge git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6
Linus Torvalds [Thu, 22 May 2008 15:08:25 +0000 (08:08 -0700)]
Merge git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6

* git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6:
  [CIFS] Fix reversed memset arguments
  Adds username in the upcall key for unattended mounts with keytab
  [CIFS] Remove redundant NULL check

16 years ago[CIFS] Fix reversed memset arguments
Dave Jones [Thu, 22 May 2008 14:20:21 +0000 (14:20 +0000)]
[CIFS] Fix reversed memset arguments

Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
16 years agoAdds username in the upcall key for unattended mounts with keytab
Igor Mammedov [Wed, 2 Apr 2008 13:33:47 +0000 (17:33 +0400)]
Adds username in the upcall key for unattended mounts with keytab

Signed-off-by: Igor Mammedov <niallain@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
16 years agoMerge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6
Linus Torvalds [Thu, 22 May 2008 05:14:39 +0000 (22:14 -0700)]
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6:
  net: The world is not perfect patch.
  tcp: Make prior_ssthresh a u32
  xfrm_user: Remove zero length key checks.
  net/ipv4/arp.c: Use common hex_asc helpers
  cassini: Only use chip checksum for ipv4 packets.
  tcp: TCP connection times out if ICMP frag needed is delayed
  netfilter: Move linux/types.h inclusions outside of #ifdef __KERNEL__
  af_key: Fix selector family initialization.
  libertas: Fix ethtool statistics
  mac80211: fix NULL pointer dereference in ieee80211_compatible_rates
  mac80211: don't claim iwspy support
  orinoco_cs: add ID for SpeedStream wireless adapters
  hostap_cs: add ID for Conceptronic CON11CPro
  rtl8187: resource leak in error case
  ath5k: Fix loop variable initializations

16 years agoMerge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6
Linus Torvalds [Thu, 22 May 2008 05:00:12 +0000 (22:00 -0700)]
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6:
  sparc64: Prevent stack backtrace false positives on trap frames.
  sparc64: Fix stack tracing through trap frames.
  sparc64: Fix kernel thread stack termination.
  sunhv: Fix locking in non-paged I/O case.

16 years agosparc64: Prevent stack backtrace false positives on trap frames.
David S. Miller [Thu, 22 May 2008 04:50:01 +0000 (21:50 -0700)]
sparc64: Prevent stack backtrace false positives on trap frames.

When we fully commit to returning back to kernel mode from
a trap, zero out the regs->magic value to prevent false
positives during stack backtraces.

Signed-off-by: David S. Miller <davem@davemloft.net>
16 years ago[CIFS] Remove redundant NULL check
Steve French [Thu, 22 May 2008 02:02:03 +0000 (02:02 +0000)]
[CIFS] Remove redundant NULL check

Noticed by Coverity checker.

Signed-off-by: Steve French <sfrench@us.ibm.com>
16 years agosparc64: Fix stack tracing through trap frames.
David S. Miller [Thu, 22 May 2008 01:15:53 +0000 (18:15 -0700)]
sparc64: Fix stack tracing through trap frames.

The offset to the pt_regs area was wrong, so we weren't
looking at the right location for the magic cookie.

A trap frame is composed of a "struct sparc_stackf" then
a "struct pt_regs", the code was using "struct reg_window"
instead of "struct sparc_stackf".

Signed-off-by: David S. Miller <davem@davemloft.net>
16 years agosparc64: Fix kernel thread stack termination.
David S. Miller [Thu, 22 May 2008 01:14:28 +0000 (18:14 -0700)]
sparc64: Fix kernel thread stack termination.

Because of the silly way I set up the initial stack for
new kernel threads, there is a loop at the top of the
stack.

To fix this, properly add another stack frame that is copied
from the parent and terminate it in the child by setting
the frame pointer in that frame to zero.

Signed-off-by: David S. Miller <davem@davemloft.net>
16 years agonet: The world is not perfect patch.
Rami Rosen [Thu, 22 May 2008 00:47:54 +0000 (17:47 -0700)]
net: The world is not perfect patch.

  Unless there will be any objection here, I suggest consider the
following patch which simply removes the code for the
-DI_WISH_WORLD_WERE_PERFECT in the three methods which use it.

The compilation errors we get when using -DI_WISH_WORLD_WERE_PERFECT
show that this code was not built and not used for really a long time.

Signed-off-by: Rami Rosen <ramirose@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
16 years agotcp: Make prior_ssthresh a u32
Ilpo Järvinen [Thu, 22 May 2008 00:40:05 +0000 (17:40 -0700)]
tcp: Make prior_ssthresh a u32

If previous window was above representable values of u16,
strange things will happen if undo with the truncated value
is called for. Alternatively, this could be fixed by some
max trickery but that would limit undoing high-speed undos.

Adds 16-bit hole but there isn't anything to fill it with.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
16 years agoxfrm_user: Remove zero length key checks.
David S. Miller [Thu, 22 May 2008 00:36:21 +0000 (17:36 -0700)]
xfrm_user: Remove zero length key checks.

The crypto layer will determine whether that is valid
or not.

Suggested by Herbert Xu, based upon a report and patch
by Martin Willi.

Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
16 years agonet/ipv4/arp.c: Use common hex_asc helpers
Denis Cheng [Thu, 22 May 2008 00:34:32 +0000 (17:34 -0700)]
net/ipv4/arp.c: Use common hex_asc helpers

Here the local hexbuf is a duplicate of global const char hex_asc from
lib/hexdump.c, except the hex letters' cases:

const char hexbuf[] = "0123456789ABCDEF";

const char hex_asc[] = "0123456789abcdef";

and here to print HW addresses, the hex cases are not significant.

Thanks to Harvey Harrison to introduce the hex_asc_hi/hex_asc_lo helpers.

Signed-off-by: Denis Cheng <crquan@gmail.com>
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
16 years agocassini: Only use chip checksum for ipv4 packets.
David S. Miller [Thu, 22 May 2008 00:05:34 +0000 (17:05 -0700)]
cassini: Only use chip checksum for ipv4 packets.

According to David Monro, at least with Natsemi Saturn chips the
cassini driver has some trouble with ipv6 checksums.

Until we have more information about what's going on here, only
use the chip checksums for ipv4.

This workaround was suggested and tested by David.

Update version and release date.

Signed-off-by: David S. Miller <davem@davemloft.net>