[PATCH V3 0/6] perf: Driver specific configuration for PMU

Mathieu Poirier
2016-07-28T21:42:27Z

This patchset adds the possiblity of specifying PMU driver configuration
directly from the perf command line. Anything that falls within the
event specifiers '/.../' and that is preceded by the '@' symbol is
treated as a configurable. Two formats are supported, @cfg and
@cfg=config.

For example:

perf record -e some_event/@cfg1/ ...

or

perf record -e some_event/@cfg2=config/ ...

or

perf record -e some_event/@cfg1,@cfg2=config/ ...

The above are all valid configuration and will see the strings 'cfg1'
and 'cfg2=config' sent to the PMU driver for parsing and interpretation
using the existing ioctl() mechanism.

The primary customers for this feature are the CoreSight drivers where
the selection of a sink (where trace data is accumulated) needs to be
done in a previous, and separated step, from the launching of the perf
command.

As such something that used to be a two-step process:

# echo 1 > /sys/bus/coresight/devices/20070000.etr/enable_sink
# perf record -e cs_etm//u --per-thread uname

is integrated in a single command:

# perf record -e cs_etm/@sink=20070000.etr/u --per-thread uname

The patches include both the kernel and user space part so that the
solution is complete and found in a single place.

It is based on [1] and assumes this set [2] has been applied. I will
be happy to merge the patchsets if it easier for maintainers to apply,
simply let me know.

Thanks,
Mathieu

Changes for V3:
- Added comment for function drv_str() that explains the reason for
keeping the entire token intact.
- Added driver config terms to the existing list of config terms.
- Added documenation for driver specific configuration.
- Pushing PMU driver configuration for 'perf stat' as well.
- Preventing users from selecting a sink from sysFS _and_ perf.

Changes for V2:
- Rebased to [1] as per Jiri's request.

[1]. git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux.git perf/core
[2]. https://lkml.org/lkml/2016/7/20/519

Mathieu Poirier (6):
perf/core: Adding PMU driver specific configuration
perf: Passing struct perf_event to function setup_aux()
perf tools: add infrastructure for PMU specific configuration
perf tools: pushing driver configuration down to the kernel
coresight: adding sink parameter to function coresight_build_path()
coresight: etm-perf: incorporating sink definition from cmd line

arch/x86/events/intel/bts.c | 4 +-
arch/x86/events/intel/pt.c | 5 +-
drivers/hwtracing/coresight/coresight-etm-perf.c | 105 ++++++++++++++++++++++-
drivers/hwtracing/coresight/coresight-priv.h | 3 +-
drivers/hwtracing/coresight/coresight.c | 43 +++++++---
include/linux/perf_event.h | 11 ++-
include/uapi/linux/perf_event.h | 1 +
kernel/events/core.c | 16 ++++
kernel/events/ring_buffer.c | 2 +-
tools/include/uapi/linux/perf_event.h | 1 +
tools/perf/Documentation/perf-record.txt | 12 +++
tools/perf/builtin-record.c | 9 ++
tools/perf/builtin-stat.c | 8 ++
tools/perf/util/evlist.c | 21 +++++
tools/perf/util/evlist.h | 3 +
tools/perf/util/evsel.c | 24 ++++++
tools/perf/util/evsel.h | 5 ++
tools/perf/util/parse-events.c | 7 +-
tools/perf/util/parse-events.h | 1 +
tools/perf/util/parse-events.l | 22 +++++
tools/perf/util/parse-events.y | 11 +++
21 files changed, 290 insertions(+), 24 deletions(-)

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2.7.4