perf tests: Fix flakiness in branch stack sampling tests

The branch stack sampling test (test 130) runs short iteration-based
workloads to verify syscall, kernel, and trap branch stack sampling.
Specifically, `test_syscall()` and `test_kernel_branches()` run `perf
bench syscall basic` with loop counts of 8000 and 1000, and
`test_trap_eret_branches()` runs `traploop` with 1000 iterations.

Because these loop limits are extremely small, the total benchmark
runtimes last only a few milliseconds (or less). Under high load,
virtualization, or coarse sampling conditions, PMU cycle sampling fails to
capture enough samples inside the brief benchmark loops. This leads to
false negatives where the script output lacks the expected syscall,
kernel, or trap branch entries (e.g. "ERROR: Branches missing getppid[^
]*/SYSCALL/").

Fix this by increasing the workload loop counts to 100,000 across all
three test sections. Running 100,000 loops still finishes virtually
instantaneously (less than 0.1 seconds), but generates enough iterations
to guarantee robust branch stack capture.

Fixes: b55878c90ab9 ("perf test: Add test for branch stack sampling")
Assisted-by: Antigravity:gemini-3.1-pro
Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>

0 files changed, 0 insertions, 0 deletions