perf(turbopack): use trace_span in tracing::instrument, improve by 1x

[xusd320]

Follow #2468

Improve tracing span in next.js

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[gemini-code-assist]

Summary of Changes

Hello @xusd320, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request focuses on optimizing the tracing instrumentation within Turbopack by adjusting the verbosity of several tracing spans. By downgrading these spans from the INFO level to the TRACE level, the change aims to improve performance by reducing the default logging overhead, allowing for more detailed diagnostics only when explicitly needed. Additionally, it includes an update to the next.js subproject.

Highlights

• Tracing Level Adjustment: The pull request updates several tracing spans from info_span! to trace_span!, effectively changing their default logging verbosity from INFO to TRACE.
• Performance Optimization: This change is a performance improvement, as indicated by the perf prefix in the title, by reducing the overhead of tracing for less critical operations that are now captured at a finer-grained trace level.
• Next.js Subproject Update: The next.js subproject has been updated to a newer commit, reflecting upstream changes or dependencies.

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[gemini-code-assist]

Code Review

This pull request improves performance by changing several info_span! macro calls to trace_span!. This is a good optimization as it reduces tracing overhead in default configurations by moving these spans to a more verbose tracing level.

I've made a few suggestions to improve consistency in how trace_span! is used across the modified files. By importing the macro at the top of each file, the code becomes more uniform and slightly easier to read.

Overall, the changes are correct and effectively address the goal of improving performance.

[gemini-code-assist]

For consistency with other files in this PR (e.g., crates/pack-api/src/app.rs), consider importing trace_span at the top of the file and using it directly without the tracing:: prefix. This would make the style for using tracing spans uniform across the codebase.

// at the top of the file
use tracing::{Instrument, trace_span};

// ...

// here
let span = trace_span!("emitting");