feat(procfs): improve standard /proc entries and add /proc/uptime

[jiuyue486]

This PR improves several standard procfs entries in DragonOS.

Changes included:

• add /proc/uptime
• improve /proc/meminfo and expose MemAvailable
• improve /proc/stat and provide btime
• improve /proc/[pid]/status for stable process-readable output
• improve /proc/[pid]/stat
• fix stale /proc/ entries after process reap

Validation:

• cat /proc/uptime
• cat /proc/meminfo
• cat /proc/stat
• cat /proc/1/status
• cat /proc/1/stat
• verify /proc/ disappears after process reap

Closes #1751

[fslongjin]

这个行为与Linux不一致。

[fslongjin]

@claude review

[dragonos-community-ai-pr-reviewer]

Claude finished @fslongjin's task in 5m 51s —— View job

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PR Review for #1807: feat(procfs): improve standard /proc entries and add /proc/uptime

I'll review the PR changes and provide feedback. Here's my plan:

• Gather context and examine PR changes
• Check the existing review comment about inconsistency at kernel/src/filesystem/procfs/pid/status.rs:149
• Review each changed file for correctness, consistency with Linux behavior, and potential issues
• Provide comprehensive review feedback
• Suggest fixes if needed

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Review Summary

The existing review comment is correct: line 149 in kernel/src/filesystem/procfs/pid/status.rs contains a separator line that doesn't exist in Linux's /proc/[pid]/status. Beyond this, I've identified several other Linux compatibility issues in the status file implementation.

Key Findings:

1. /proc/[pid]/status has significant Linux incompatibilities:

   • Header lines "DragonOS Process Status" and separator (lines 147-149)
   • Field format uses "{key:<12}: {value}" instead of Linux's "{key}:\t{value}"
   • Non-standard fields (Kthread, CpuId, Priority, Preempt, Vruntime, ExecRuntime, StartTime, Flags)
   • Missing many standard Linux fields

2. Other /proc entries are generally good:

   • /proc/meminfo: Format matches Linux, though field set is limited and MemAvailable calculation is simplistic
   • /proc/stat: Good Linux compatibility, includes btime
   • /proc/uptime: Correct format, idle time calculation looks proper
   • PID directory cleanup: Good fixes for stale entries
   • /proc/[pid]/stat: Linux-compatible format with placeholder zeros

Recommendations:

1. Priority fix: Align /proc/[pid]/status with Linux format. At minimum, remove the non-standard header lines: Fix this →
2. Consider adopting tab-separated field format and adding missing standard Linux fields over time.
3. The other changes in this PR are positive improvements that enhance Linux compatibility.

Next Steps:

Would you like me to implement specific fixes for the status file? I can:

• Remove the header/separator lines (minimal fix)
• Adjust field formatting to use tabs
• Begin adding missing Linux-standard fields (this would be a larger effort)

The choice depends on how closely you want to match Linux behavior versus maintaining DragonOS-specific extensions.

[jiuyue486]

收到 我修改好之后再交一次pr可以吗，龙学长 王鹏

---- Replied Message ---- | From | ***@***.***> | | Date | 03/09/2026 10:42 | | To | ***@***.***> | | Cc | ***@***.***>***@***.***> | | Subject | Re: [DragonOS-Community/DragonOS] feat(procfs): improve standard /proc entries and add /proc/uptime (PR #1807) | @fslongjin requested changes on this pull request. In kernel/src/filesystem/procfs/pid/status.rs:

+

+ s.push_str("DragonOS Process Status\n"); + s.push_str("=======================\n"); + 这个行为与Linux不一致。 — Reply to this email directly, view it on GitHub, or unsubscribe. You are receiving this because you authored the thread.Message ID: ***@***.***>

[fslongjin]

1. 需要对照Linux 6.6.21的代码来做
2. 本地下好上述linux代码，让ai参考这个的行为来review
3. 每个pr功能应该单一，而不是一次改一堆东西
4. 新增的功能应当在dunitest下面补充单元测试

[jiuyue486]

收到 学长 今天上完课我就回去再修改一下

…

---- 回复的原邮件 ---- | 发件人 | ***@***.***> | | 日期 | 2026年03月09日 10:51 | | 收件人 | ***@***.***> | | 抄送至 | ***@***.***>***@***.***> | | 主题 | Re: [DragonOS-Community/DragonOS] feat(procfs): improve standard /proc entries and add /proc/uptime (PR #1807) | fslongjin left a comment (DragonOS-Community/DragonOS#1807) 需要对照Linux 6.6.21的代码来做 本地下好上述linux代码，让ai参考这个的行为来review 每个pr功能应该单一，而不是一次改一堆东西 新增的功能应当在dunitest下面补充单元测试 — Reply to this email directly, view it on GitHub, or unsubscribe. You are receiving this because you authored the thread.Message ID: ***@***.***>