linux-stable.git/kernel/trace/trace_selftest.c, branch linux-2.6.29.y

tracing: limit the number of loops the ring buffer self test can make

2009-02-19T03:50:01+00:00

Impact: prevent deadlock if ring buffer gets corrupted

This patch adds a paranoid check to make sure the ring buffer consumer
does not go into an infinite loop. Since the ring buffer has been set
to read only, the consumer should not loop for more than the ring buffer
size. A check is added to make sure the consumer does not loop more than
the ring buffer size.

Signed-off-by: Steven Rostedt

tracing: disable tracing while testing ring buffer

2009-02-19T03:04:01+00:00

Impact: fix to prevent hard lockup on self tests

If one of the tracers are broken and is constantly filling the ring
buffer while the test of the ring buffer is running, it will hang
the box. The reason is that the test is a consumer that will not
stop till the ring buffer is empty. But if the tracer is broken and
is constantly producing input to the buffer, this test will never
end. The result is a lockup of the box.

This happened when KALLSYMS was not defined and the dynamic ftrace
test constantly filled the ring buffer, because the filter failed
and all functions were being traced. Something was being called
that constantly filled the buffer.

Signed-off-by: Steven Rostedt

tracing/ftrace: change the type of the init() callback

2008-11-16T06:55:23+00:00

Impact: extend the ->init() method with the ability to fail

This bring a way to know if the initialization of a tracer successed.
A tracer must return 0 on success and a traditional error (ie:
-ENOMEM) if it fails.

If a tracer fails to init, it is free to print a detailed warn. The
tracing api will not and switch to a new tracer will just return the
error from the init callback.

Note: this will be used for the return tracer.

Signed-off-by: Frederic Weisbecker 
Signed-off-by: Ingo Molnar

ftrace: replace raw_local_irq_save with local_irq_save

2008-11-16T06:35:37+00:00

Impact: fix lockdep disabling itself when function tracing is enabled

The raw_local_irq_saves used in ftrace is causing problems with
lockdep. (it thinks the irq flags are out of sync and disables
itself with a warning)

The raw ops here are not needed, and the normal local_irq_save is fine.

Signed-off-by: Steven Rostedt 
Signed-off-by: Ingo Molnar

ftrace: add tracer called branch

2008-11-12T21:28:25+00:00

Impact: added new branch tracer

Currently the tracing of branch profiling (unlikelys and likelys hit)
is only activated by the iter_ctrl. This patch adds a tracer called
"branch" that will just trace the branch profiling. The advantage
of adding this tracer is that it can be added to the ftrace selftests
on startup.

Signed-off-by: Steven Rostedt 
Signed-off-by: Ingo Molnar

ftrace: force pass of preemptoff selftest

2008-11-08T08:51:49+00:00

Impact: preemptoff not tested in selftest

Due to the BKL not being preemptable anymore, the selftest of the
preemptoff code can not be tested. It requires that it is called
with preemption enabled, but since the BKL is held, that is no
longer the case.

This patch simply skips those tests if it detects that the context
is not preemptable. The following will now show up in the tests:

Testing tracer preemptoff: can not test ... force PASSED
Testing tracer preemptirqsoff: can not test ... force PASSED

When the BKL is removed, or it becomes preemptable once again, then
the tests will be performed.

Signed-off-by: Steven Rostedt 
Signed-off-by: Ingo Molnar

ftrace: remove trace array ctrl

2008-11-08T08:51:39+00:00

Impact: remove obsolete variable in trace_array structure

With the new start / stop method of ftrace, the ctrl variable
in the trace_array structure is now obsolete. Remove it.

Signed-off-by: Steven Rostedt 
Signed-off-by: Ingo Molnar

ftrace: remove ctrl_update method

2008-11-08T08:51:34+00:00

Impact: Remove the ctrl_update tracer method

With the new quick start/stop method of tracing, the ctrl_update
method is out of date.

Signed-off-by: Steven Rostedt 
Signed-off-by: Ingo Molnar

ftrace: remove daemon

2008-10-23T14:00:22+00:00

The ftrace daemon is complex and error prone.  This patch strips it out
of the code.

Signed-off-by: Steven Rostedt 
Signed-off-by: Ingo Molnar

ftrace: rename FTRACE to FUNCTION_TRACER

2008-10-20T16:27:03+00:00

Due to confusion between the ftrace infrastructure and the gcc profiling
tracer "ftrace", this patch renames the config options from FTRACE to
FUNCTION_TRACER.  The other two names that are offspring from FTRACE
DYNAMIC_FTRACE and FTRACE_MCOUNT_RECORD will stay the same.

This patch was generated mostly by script, and partially by hand.

Signed-off-by: Steven Rostedt 
Signed-off-by: Ingo Molnar