perf test: Add a test for default perf stat command

[ Upstream commit 65d11821 ]

Test that one cycles event is opened for each core PMU when "perf stat"
is run without arguments.

The event line can either be output as "pmu/cycles/" or just "cycles" if
there is only one PMU. Include 2 spaces for padding in the one PMU case
to avoid matching when the word cycles is included in metric
descriptions.

Acked-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: James Clark <james.clark@linaro.org>
Cc: Yang Jihong <yangjihong@bytedance.com>
Cc: Dominique Martinet <asmadeus@codewreck.org>
Cc: Colin Ian King <colin.i.king@gmail.com>
Cc: Howard Chu <howardchu95@gmail.com>
Cc: Ze Gao <zegao2021@gmail.com>
Cc: Yicong Yang <yangyicong@hisilicon.com>
Cc: Weilin Wang <weilin.wang@intel.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Jing Zhang <renyu.zj@linux.alibaba.com>
Cc: Yang Li <yang.lee@linux.alibaba.com>
Cc: Leo Yan <leo.yan@linux.dev>
Cc: ak@linux.intel.com
Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Yanteng Si <siyanteng@loongson.cn>
Cc: Sun Haiyong <sunhaiyong@loongson.cn>
Cc: John Garry <john.g.garry@oracle.com>
Link: https://lore.kernel.org/r/20240926144851.245903-8-james.clark@linaro.org


Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Stable-dep-of: 24937ee8 ("perf evsel: Ensure the fallback message is always written to")
Signed-off-by: Sasha Levin <sashal@kernel.org>