dd: simplify match

[oech3]

No description provided.

[github-actions]

GNU testsuite comparison:

Skipping an intermittent issue tests/date/resolution (passes in this run but fails in the 'main' branch)
Skipping an intermittent issue tests/tail/retry (passes in this run but fails in the 'main' branch)
Skip an intermittent issue tests/tail/tail-n0f (was skipped on 'main', now failing)

[codspeed-hq]

Merging this PR will improve performance by 24.65%

⚠️ Different runtime environments detected

Some benchmarks with significant performance changes were compared across different runtime environments,
which may affect the accuracy of the results.

Open the report in CodSpeed to investigate

⚡ 1 improved benchmark
✅ 317 untouched benchmarks
⏩ 73 skipped benchmarks¹

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
⚡	Simulation	df_with_path	305.3 µs	244.9 µs	+24.65%

Tip

Curious why this is faster? Comment @codspeedbot explain why this is faster on this PR, or directly use the CodSpeed MCP with your agent.

---

_{Comparing oech3:dd-match (62ab25c) with main (197eac4)}

Footnotes

1. 73 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[cakebaker]

Wouldn't it be cleaner to use continue in the _ arm? Something like:

        let tp = match alarm.get_trigger() {
            ALARM_TRIGGER_TIMER => ProgUpdateType::Periodic,
            ALARM_TRIGGER_SIGNAL => ProgUpdateType::Signal,
            _ => continue,
        };
        let prog_update = ProgUpdate::new(rstat, wstat, start.elapsed(), tp);
        prog_tx.send(prog_update).unwrap_or(());

[cakebaker]

Another alternative:

        let update_type = match alarm.get_trigger() {
            ALARM_TRIGGER_TIMER => Some(ProgUpdateType::Periodic),
            ALARM_TRIGGER_SIGNAL => Some(ProgUpdateType::Signal),
            _ => None,
        };
        if let Some(tp) = update_type {
            let prog_update = ProgUpdate::new(rstat, wstat, start.elapsed(), tp);
            prog_tx.send(prog_update).unwrap_or(());
        }