linux-toradex.git/kernel/trace/trace_event_perf.c, branch v2.6.38.5

tracing: New flag to allow non privileged users to use a trace event

2010-11-18T13:37:40+00:00

This adds a new trace event internal flag that allows them to be
used in perf by non privileged users in case of task bound tracing.

This is desired for syscalls tracepoint because they don't leak
global system informations, like some other tracepoints.

Signed-off-by: Frederic Weisbecker 
Cc: Ingo Molnar 
Cc: Peter Zijlstra 
Cc: Arnaldo Carvalho de Melo 
Cc: Thomas Gleixner 
Cc: Steven Rostedt 
Cc: Li Zefan 
Cc: Jason Baron

perf: Rework the PMU methods

2010-09-09T18:46:30+00:00

Replace pmu::{enable,disable,start,stop,unthrottle} with
pmu::{add,del,start,stop}, all of which take a flags argument.

The new interface extends the capability to stop a counter while
keeping it scheduled on the PMU. We replace the throttled state with
the generic stopped state.

This also allows us to efficiently stop/start counters over certain
code paths (like IRQ handlers).

It also allows scheduling a counter without it starting, allowing for
a generic frozen state (useful for rotating stopped counters).

The stopped state is implemented in two different ways, depending on
how the architecture implemented the throttled state:

 1) We disable the counter:
    a) the pmu has per-counter enable bits, we flip that
    b) we program a NOP event, preserving the counter state

 2) We store the counter state and ignore all read/overflow events

Signed-off-by: Peter Zijlstra 
Cc: paulus 
Cc: stephane eranian 
Cc: Robert Richter 
Cc: Will Deacon 
Cc: Paul Mundt 
Cc: Frederic Weisbecker 
Cc: Cyrill Gorcunov 
Cc: Lin Ming 
Cc: Yanmin 
Cc: Deng-Cheng Zhu 
Cc: David Miller 
Cc: Michael Cree 
LKML-Reference: 
Signed-off-by: Ingo Molnar

Merge branch 'perf/urgent' into perf/core

2010-09-09T18:40:08+00:00

Merge reason: Pick up pending fixes before applying dependent new changes.

Signed-off-by: Ingo Molnar

perf, trace: Fix module leak

2010-09-09T18:38:51+00:00

Commit 1c024eca (perf, trace: Optimize tracepoints by using
per-tracepoint-per-cpu hlist to track events) caused a module
refcount leak.

Reported-And-Tested-by: Avi Kivity 
Signed-off-by: Peter Zijlstra 
LKML-Reference: <4C7E1F12.8030304@cn.fujitsu.com>
Signed-off-by: Ingo Molnar

perf, tracing: add missing __percpu markups

2010-08-18T23:33:05+00:00

ftrace_event_call->perf_events, perf_trace_buf,
fgraph_data->cpu_data and some local variables are percpu pointers
missing __percpu markups. Add them.

Signed-off-by: Namhyung Kim 
Acked-by: Tejun Heo 
Cc: Steven Rostedt 
Cc: Ingo Molnar 
Cc: Peter Zijlstra 
Cc: Arnaldo Carvalho de Melo 
Cc: Paul Mackerras 
Cc: Stephane Eranian 
LKML-Reference: <1281498479-28551-1-git-send-email-namhyung@gmail.com>
Signed-off-by: Frederic Weisbecker

perf: Humanize the number of contexts

2010-08-18T23:32:53+00:00

Instead of hardcoding the number of contexts for the recursions
barriers, define a cpp constant to make the code more
self-explanatory.

Signed-off-by: Frederic Weisbecker 
Cc: Ingo Molnar 
Cc: Peter Zijlstra 
Cc: Arnaldo Carvalho de Melo 
Cc: Paul Mackerras 
Cc: Stephane Eranian

perf: Use tracepoint_synchronize_unregister() to flush any pending tracepoint call

2010-08-01T23:30:56+00:00

We use synchronize_sched() to ensure a tracepoint won't be called
while/after we release the perf buffers it references.

But the tracepoint API has its own API for that:
tracepoint_synchronize_unregister(). Use it instead as it's
self-explanatory and eases maintainance.

Signed-off-by: Frederic Weisbecker 
Cc: Ingo Molnar 
Cc: Peter Zijlstra 
Cc: Arnaldo Carvalho de Melo 
Cc: Mathieu Desnoyers 
Cc: Steven Rostedt 
Cc: Li Zefan

tracing: Use class->reg() for all registering of events

2010-06-29T01:13:14+00:00

Because kprobes and syscalls need special processing to register
events, the class->reg() method was created to handle the differences.

But instead of creating a default ->reg for perf and ftrace events,
the code was scattered with:

	if (class->reg)
		class->reg();
	else
		default_reg();

This is messy and can also lead to bugs.

This patch cleans up this code and creates a default reg() entry for
the events allowing for the code to directly call the class->reg()
without the condition.

Reported-by: Peter Zijlstra 
Acked-by: Peter Zijlstra 
Signed-off-by: Steven Rostedt

Merge branch 'linus' into perf/core

2010-06-28T20:33:24+00:00

Reason: Further changes conflict with upstream fixes

Signed-off-by: Thomas Gleixner

perf/tracing: Fix regression of perf losing kprobe events

2010-06-11T00:56:54+00:00

With the addition of the code to shrink the kernel tracepoint
infrastructure, we lost kprobes being traced by perf. The reason
is that I tested if the "tp_event->class->perf_probe" existed before
enabling it. This prevents "ftrace only" events (like the function
trace events) from being enabled by perf.

Unfortunately, kprobe events do not use perf_probe. This causes
kprobes to be missed by perf. To fix this, we add the test to
see if "tp_event->class->reg" exists as well as perf_probe.

Normal trace events have only "perf_probe" but no "reg" function,
and kprobes and syscalls have the "reg" but no "perf_probe".
The ftrace unique events do not have either, so this is a valid
test. If a kprobe or syscall is not to be probed by perf, the
"reg" function is called anyway, and will return a failure and
prevent perf from probing it.

Reported-by: Srikar Dronamraju 
Tested-by: Srikar Dronamraju 
Acked-by: Peter Zijlstra 
Signed-off-by: Steven Rostedt