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The waiting helpers implement timeouts using: date +%s%1N This relies on GNU coreutils date truncating %N to the specified width, so %1N yields tenths of a second. Rust coreutils (uutils) interprets the width differently and does not truncate the nanoseconds field. Consequently "date +%1N" returns all nine nanosecond digits, causing the elapsed-time calculation to be done in nanoseconds while timeout values remain in tenths of a second. As a result, timeout comparisons succeed immediately and the waiting helpers time out on their first iteration. This causes test_intel_pt.sh to fail on systems using uutils "date". Avoid implementation-specific date formatting entirely. Instead, wait for 100 ms on each iteration and count the timeout down. Besides fixing the portability issue, this removes the busy-waiting behaviour in wait_for_perf_to_start(), which could otherwise consume CPU while waiting for perf record to start. Since the timeout is now based on repeated sleeps, it is only approximate. Update the comments accordingly. Also make is_running() wait for exactly the documented number of tenths by changing its timeout test from -gt to the new logic, and quote tm_out in the modified code. Reviewed-by: Ian Rogers <irogers@google.com> Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |
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| .. | ||
| attr.py | ||
| perf_has_symbol.sh | ||
| perf_json_output_lint.py | ||
| perf_metric_validation_rules.json | ||
| perf_metric_validation.py | ||
| perf_record.sh | ||
| probe_vfs_getname.sh | ||
| probe.sh | ||
| setup_python.sh | ||
| stat_output.sh | ||
| waiting.sh | ||