[PATCH v5 0/4] Add support for parametrized events

Sukadev Bhattiprolu sukadev at linux.vnet.ibm.com
Wed Dec 3 13:09:34 AEDT 2014


Description of "event parameters" from the documentation patch:

    Event parameters are a basic way for partial events to be specified in
    sysfs with per-event names given to the fields that need to be filled in
    when using a particular event.

    It is intended for supporting cases where the single 'cpu' parameter is
    insufficient. For example, POWER 8 has events for physical
    sockets/cores/cpus that are accessible from with virtual machines. To
    keep using the single 'cpu' parameter we'd need to perform a mapping
    between Linux's cpus and the physical machine's cpus (in this case
    Linux is running under a hypervisor). This isn't possible because
    bindings between our cpus and physical cpus may not be fixed, and we
    probably won't have a "cpu" on each physical cpu.

Description of the sysfs contents when events are parameterized (copied from an
included patch):

	Examples:

		domain=0x1,offset=0x8,starting_index=$core

	In the case of the last example, a value replacing "$core" would need
	to be provided by the user selecting the particular event. This is
	refered to as "event parameterization". All non-numerical values
	indicate an event parameter.

Notes on how perf-list displays parameterized events

	PARAMETERIZED EVENTS
	--------------------

	Some pmu events listed by 'perf list' will be displayed with '$xyz' in
	them. For example:

	  hv_24x7/HPM_THREAD_NAP_CCYC__PHYS_CORE,starting_index=$core/

	This means that when provided as an event, a value for $core must also
	be supplied. For example:

	  perf stat  -e \
	  	'hv_24x7/HPM_THREAD_NAP_CCYC__PHYS_CORE,starting_index=2'
		...

Changelog[v5]
	- [Jiri Olsa, Peter Zijlstra] Use '$arg' notation rather than ?
	  to indicate event parameters.

	- [Michael Ellerman] Separate the kernel and tool patches in the
	  patchset into different patchsets.

Changelog[v4]
	- [Jiri Olsa] Rebase to perf/core tree (fix small merge conflict)

Changelog[v3]
	- [Jiri Olsa] Changed the event parameters are specified. If
	  event file specifes 'param=val' make the usage 'param=123'
	  rather than 'val=123'. (patch 1,2/10)
	- Shortened event names using "PHYS" and "VCPU" (patch 4/10)
	- Print help message if invalid parameter is specified or required
	  parameter is missing.
	- Moved 3 patches that are unrelated to parametrized events into
	  a separate patchset.
	- Reordered patches so code changes come first.

Changelog[v2]
	- [Joe Perches, David Laight] Use beNN_to_cpu() instead of guessing
	  the size from type.
	- Use kmem_cache_free() to free page allocated with kmem_cache_alloc().
	- Rebase to recent kernel


Cody P Schafer (4):
  tools/perf: support parsing parameterized events
  tools/perf: extend format_alias() to include event parameters
  perf Documentation: add event parameters
  tools/perf: Document parameterized and symbolic events

 .../testing/sysfs-bus-event_source-devices-events  |  6 ++
 tools/perf/Documentation/perf-list.txt             | 13 +++
 tools/perf/Documentation/perf-record.txt           | 12 +++
 tools/perf/Documentation/perf-stat.txt             | 20 ++++-
 tools/perf/util/parse-events.h                     |  1 +
 tools/perf/util/pmu.c                              | 92 +++++++++++++++++++---
 6 files changed, 128 insertions(+), 16 deletions(-)

-- 
1.8.3.1



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