[PATCH v3 0/3] perf list: Remove duplicate PMUs

[Ian Rogers <irogers@google.com>]

When there are multiple PMUs, differing by ordered suffixes, by
default only display one. This avoids repeated listing of events, in
particular when there are 10s of uncore PMUs. If "-v" is passed to
"perf list" then still list all PMUs.

Listing fewer PMU/event combinations helps speed the all PMU event
tests.

Before:
```
$ perf list
...
  uncore_imc_free_running_0/data_read/               [Kernel PMU event]
  uncore_imc_free_running_0/data_total/              [Kernel PMU event]
  uncore_imc_free_running_0/data_write/              [Kernel PMU event]
  uncore_imc_free_running_1/data_read/               [Kernel PMU event]
  uncore_imc_free_running_1/data_total/              [Kernel PMU event]
  uncore_imc_free_running_1/data_write/              [Kernel PMU event]
```

After:
```
$ perf list
...
  uncore_imc_free_running/data_read/                 [Kernel PMU event]
  uncore_imc_free_running/data_total/                [Kernel PMU event]
  uncore_imc_free_running/data_write/                [Kernel PMU event]
...
$ perf list -v
...
  uncore_imc_free_running_0/data_read/               [Kernel PMU event]
  uncore_imc_free_running_0/data_total/              [Kernel PMU event]
  uncore_imc_free_running_0/data_write/              [Kernel PMU event]
  uncore_imc_free_running_1/data_read/               [Kernel PMU event]
  uncore_imc_free_running_1/data_total/              [Kernel PMU event]
  uncore_imc_free_running_1/data_write/              [Kernel PMU event]
...
```

The PMUs are sorted by name then suffix as a part of this change.

v3: Add detail to patch 1 sorting commit message about the suffix and
    why sorting is necessary.
v2: List all PMUs when "-v" is passed as suggested by John Garry
    <john.g.garry@oracle.com>.

Ian Rogers (3):
  perf pmus: Sort pmus by name then suffix
  perf pmus: Add scan that ignores duplicates, use for perf list
  perf pmus: Don't print duplicate PMU suffix in list by default

 tools/perf/builtin-list.c      |   8 +++
 tools/perf/util/pmus.c         | 120 +++++++++++++++++++++++++++++++--
 tools/perf/util/print-events.h |   1 +
 3 files changed, 122 insertions(+), 7 deletions(-)

-- 
2.41.0.640.ga95def55d0-goog