linux-toradex.git/tools/perf/builtin-stat.c, branch v2.6.32.9

perf: Propagate term signal to child

2009-10-04T17:37:39+00:00

If we launch the child on behalf of the user, ensure that it dies
along with ourselves when we are interrupted.

Signed-off-by: Chris Wilson 
Cc: Chris Wilson 
LKML-Reference: <1254616502-4728-1-git-send-email-chris@chris-wilson.co.uk>
Signed-off-by: Ingo Molnar

perf stat: Fix zero total printouts

2009-09-22T13:01:47+00:00

Before:

           0  sched:sched_switch #        nan M/sec

After:

           0  sched:sched_switch #      0.000 M/sec

Cc: Peter Zijlstra 
Cc: Mike Galbraith 
Cc: Paul Mackerras 
Cc: Arnaldo Carvalho de Melo 
Cc: Frederic Weisbecker 
LKML-Reference: 
Signed-off-by: Ingo Molnar

perf: Do the big rename: Performance Counters -> Performance Events

2009-09-21T12:28:04+00:00

Bye-bye Performance Counters, welcome Performance Events!

In the past few months the perfcounters subsystem has grown out its
initial role of counting hardware events, and has become (and is
becoming) a much broader generic event enumeration, reporting, logging,
monitoring, analysis facility.

Naming its core object 'perf_counter' and naming the subsystem
'perfcounters' has become more and more of a misnomer. With pending
code like hw-breakpoints support the 'counter' name is less and
less appropriate.

All in one, we've decided to rename the subsystem to 'performance
events' and to propagate this rename through all fields, variables
and API names. (in an ABI compatible fashion)

The word 'event' is also a bit shorter than 'counter' - which makes
it slightly more convenient to write/handle as well.

Thanks goes to Stephane Eranian who first observed this misnomer and
suggested a rename.

User-space tooling and ABI compatibility is not affected - this patch
should be function-invariant. (Also, defconfigs were not touched to
keep the size down.)

This patch has been generated via the following script:

  FILES=$(find * -type f | grep -vE 'oprofile|[^K]config')

  sed -i \
    -e 's/PERF_EVENT_/PERF_RECORD_/g' \
    -e 's/PERF_COUNTER/PERF_EVENT/g' \
    -e 's/perf_counter/perf_event/g' \
    -e 's/nb_counters/nb_events/g' \
    -e 's/swcounter/swevent/g' \
    -e 's/tpcounter_event/tp_event/g' \
    $FILES

  for N in $(find . -name perf_counter.[ch]); do
    M=$(echo $N | sed 's/perf_counter/perf_event/g')
    mv $N $M
  done

  FILES=$(find . -name perf_event.*)

  sed -i \
    -e 's/COUNTER_MASK/REG_MASK/g' \
    -e 's/COUNTER/EVENT/g' \
    -e 's/\/event_id/g' \
    -e 's/counter/event/g' \
    -e 's/Counter/Event/g' \
    $FILES

... to keep it as correct as possible. This script can also be
used by anyone who has pending perfcounters patches - it converts
a Linux kernel tree over to the new naming. We tried to time this
change to the point in time where the amount of pending patches
is the smallest: the end of the merge window.

Namespace clashes were fixed up in a preparatory patch - and some
stylistic fallout will be fixed up in a subsequent patch.

( NOTE: 'counters' are still the proper terminology when we deal
  with hardware registers - and these sed scripts are a bit
  over-eager in renaming them. I've undone some of that, but
  in case there's something left where 'counter' would be
  better than 'event' we can undo that on an individual basis
  instead of touching an otherwise nicely automated patch. )

Suggested-by: Stephane Eranian 
Acked-by: Peter Zijlstra 
Acked-by: Paul Mackerras 
Reviewed-by: Arjan van de Ven 
Cc: Mike Galbraith 
Cc: Arnaldo Carvalho de Melo 
Cc: Frederic Weisbecker 
Cc: Steven Rostedt 
Cc: Benjamin Herrenschmidt 
Cc: David Howells 
Cc: Kyle McMartin 
Cc: Martin Schwidefsky 
Cc: "David S. Miller" 
Cc: Thomas Gleixner 
Cc: "H. Peter Anvin" 
Cc: 
LKML-Reference: 
Signed-off-by: Ingo Molnar

perf stat: Clean up statistics calculations a bit more

2009-09-04T18:27:26+00:00

Remove some, now useless, global storage.
Don't calculate the stddev when not needed.

Signed-off-by: Peter Zijlstra 
LKML-Reference: 
Signed-off-by: Ingo Molnar

perf stat: More advanced variance computation

2009-09-04T15:38:15+00:00

Use the more advanced single pass variance algorithm outlined
on the wikipedia page. This is numerically more stable for
larger sample sets.

Signed-off-by: Peter Zijlstra 
LKML-Reference: 
Signed-off-by: Ingo Molnar

perf stat: Use stddev_mean in stead of stddev

2009-09-04T15:38:14+00:00

When we're computing the mean by sampling the distribution,
then the std dev of the mean is related to the std dev of the
sample set by:

  stddev_mean = std_dev / sqrt(N)

Which is exactly what we want.

This results in the error on the mean decreasing with
increasing number of samples.

Also fix the scaled == -1, aka not counted case.

Signed-off-by: Peter Zijlstra 
LKML-Reference: 
Signed-off-by: Ingo Molnar

perf stat: Remove the limit on repeat

2009-09-04T14:33:08+00:00

Since we don't need all the individual samples to calculate the
error remove both the limit and the storage overhead associated
with that.

Signed-off-by: Peter Zijlstra 
LKML-Reference: 
Signed-off-by: Ingo Molnar

perf stat: Change noise calculation to use stddev

2009-09-04T14:33:07+00:00

The current noise computation does:

 \Sum abs(n_i - avg(n)) * N^-1.5

Which is (afaik) not a regular noise function, and needs the
complete sample set available to post-process.

Change this to use a regular stddev computation which can be
done by keeping a two sums:

 stddev = sqrt( 1/N (\Sum n_i^2) - avg(n)^2 )

For which we only need to keep \Sum n_i and \Sum n_i^2.

Signed-off-by: Peter Zijlstra 
Cc: 
LKML-Reference: 
Signed-off-by: Ingo Molnar

perf tools: Librarize trace_event() helper

2009-08-16T21:06:45+00:00

Librarize trace_event() helper so that perf trace can use it
too. Also clean up the debug.h includes a bit.

It's not good to have it included in perf.h because it doesn't
make it flexible against other headers it may need (headers
that can also depend on perf.h and then create a recursive
header dependency).

Signed-off-by: Frederic Weisbecker 
Cc: Peter Zijlstra 
Cc: Arnaldo Carvalho de Melo 
Cc: Mike Galbraith 
LKML-Reference: <1250453149-664-1-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar

perf tools: Factorize high level dso helpers

2009-08-12T10:02:38+00:00

Factorize multiple definitions of high level dso helpers into the
symbol source file.

The side effect is a general export of the verbose and eprintf
debugging helpers into a new file dedicated to debugging purposes.

Signed-off-by: Frederic Weisbecker 
Cc: Arnaldo Carvalho de Melo 
Cc: Peter Zijlstra 
Cc: Mike Galbraith 
Cc: Brice Goglin