Export /proc/cpuinfo

kernel/src/fs/procfs/cpuinfo.rs

@@ -0,0 +1,49 @@
+// SPDX-License-Identifier: MPL-2.0
+
+//! This module offers `/proc/cpuinfo` file support, which provides
+//! information about the CPU architecture, cores, and other details.
+//!
+//! Reference: <https://man7.org/linux/man-pages/man5/proc_cpuinfo.5.html>
+
+use ostd::cpu::num_cpus;
+
+use crate::{
+    arch::cpu::CpuInfo,
+    fs::{
+        procfs::template::{FileOps, ProcFileBuilder},
+        utils::Inode,
+    },
+    prelude::*,
+};
+
+/// Represents the inode at `/proc/cpuinfo`.
+pub struct CpuInfoFileOps;
+
+impl CpuInfoFileOps {
+    /// Create a new inode for `/proc/cpuinfo`.
+    pub fn new_inode(parent: Weak<dyn Inode>) -> Arc<dyn Inode> {
+        ProcFileBuilder::new(Self).parent(parent).build().unwrap()
+    }
+
+    /// Collect and format CPU information for all cores.
+    fn collect_cpu_info() -> String {
+        let num_cpus = num_cpus() as u32;
+
+        // Iterate over each core and collect CPU information
+        (0..num_cpus)
+            .map(|core_id| {
+                let cpuinfo = CpuInfo::new(core_id);
+                cpuinfo.collect_cpu_info()
+            })
+            .collect::<Vec<String>>()
+            .join("\n\n")
+    }
+}
+
+impl FileOps for CpuInfoFileOps {
+    /// Retrieve the data for `/proc/cpuinfo`.
+    fn data(&self) -> Result<Vec<u8>> {
+        let output = Self::collect_cpu_info();
+        Ok(output.into_bytes())
+    }
+}

kernel/src/fs/procfs/mod.rs

@@ -6,6 +6,7 @@ use loadavg::LoadAvgFileOps;
 use sys::SysDirOps;
 
 use self::{
+    cpuinfo::CpuInfoFileOps,
     meminfo::MemInfoFileOps,
     pid::PidDirOps,
     self_::SelfSymOps,
@@ -21,6 +22,7 @@ use crate::{
     process::{process_table, process_table::PidEvent, Pid},
 };
 
+mod cpuinfo;
 mod filesystems;
 mod loadavg;
 mod meminfo;
@@ -110,6 +112,8 @@ impl DirOps for RootDirOps {
             MemInfoFileOps::new_inode(this_ptr.clone())
         } else if name == "loadavg" {
             LoadAvgFileOps::new_inode(this_ptr.clone())
+        } else if name == "cpuinfo" {
+            CpuInfoFileOps::new_inode(this_ptr.clone())
         } else if let Ok(pid) = name.parse::<Pid>() {
             let process_ref =
                 process_table::get_process(pid).ok_or_else(|| Error::new(Errno::ENOENT))?;
@@ -135,7 +139,8 @@ impl DirOps for RootDirOps {
             .put_entry_if_not_found("meminfo", || MemInfoFileOps::new_inode(this_ptr.clone()));
         cached_children
             .put_entry_if_not_found("loadavg", || LoadAvgFileOps::new_inode(this_ptr.clone()));
-
+        cached_children
+            .put_entry_if_not_found("cpuinfo", || CpuInfoFileOps::new_inode(this_ptr.clone()));
         for process in process_table::process_table_mut().iter() {
             let pid = process.pid().to_string();
             cached_children.put_entry_if_not_found(&pid, || {