internal/sysinfo: print cpu type from cpuinfo when internal cpu name is empty on...

Supports all linux operating systems. currently tested on x86, mips64le and loong64.

Example output:
$ go test -bench=.*
goos: linux
goarch: loong64
pkg: runtime
cpu: Loongson-3A5000-HV @ 2500.00MHz
BenchmarkSemTable/OneAddrCollision/n=1000         	   19261	     62302 ns/op
    ...

Change-Id: I02db12d70c11327e4625bb6e59f30dfaf37c2db0
Reviewed-on: https://go-review.googlesource.com/c/go/+/508735
Reviewed-by: Meidan Li <limeidan@loongson.cn>
Reviewed-by: Russ Cox <rsc@golang.org>
TryBot-Bypass: Russ Cox <rsc@golang.org>
Auto-Submit: Russ Cox <rsc@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Run-TryBot: Russ Cox <rsc@golang.org>

diff --git a/src/cmd/internal/metadata/main.go b/src/cmd/internal/metadata/main.go
index 7478eec1c9b516629d4007f2c728d1b0e8f17d3d..af46c89bf66543ed833b6e6a6094f708ca8fd7b7 100644 (file)
--- a/src/cmd/internal/metadata/main.go
+++ b/src/cmd/internal/metadata/main.go
@@ -22,7 +22,7 @@ import (
 
 func main() {
        fmt.Printf("# GOARCH: %s\n", runtime.GOARCH)
-       fmt.Printf("# CPU: %s\n", sysinfo.CPU.Name())
+       fmt.Printf("# CPU: %s\n", sysinfo.CPUName())
 
        fmt.Printf("# GOOS: %s\n", runtime.GOOS)
        ver, err := osinfo.Version()

diff --git a/src/go/build/deps_test.go b/src/go/build/deps_test.go
index 39f22af5f9a16bca73782c6337fcda362949f46b..ff03691eb90397395d0e907d2905eb249aff9a84 100644 (file)
--- a/src/go/build/deps_test.go
+++ b/src/go/build/deps_test.go
@@ -564,7 +564,7 @@ var depsRules = `
        < net/rpc/jsonrpc;
 
        # System Information
-       internal/cpu, sync
+       bufio, bytes, internal/cpu, io, os, strings, sync
        < internal/sysinfo;
 
        # Test-only

diff --git a/src/internal/sysinfo/cpuinfo_linux.go b/src/internal/sysinfo/cpuinfo_linux.go
new file mode 100644 (file)
index 0000000..aff63b3
--- /dev/null
+++ b/src/internal/sysinfo/cpuinfo_linux.go
@@ -0,0 +1,77 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package sysinfo
+
+import (
+       "bufio"
+       "bytes"
+       "io"
+       "os"
+       "strings"
+)
+
+func readLinuxProcCPUInfo(buf []byte) error {
+       f, err := os.Open("/proc/cpuinfo")
+       if err != nil {
+               return err
+       }
+       defer f.Close()
+
+       _, err = io.ReadFull(f, buf)
+       if err != nil && err != io.ErrUnexpectedEOF {
+               return err
+       }
+
+       return nil
+}
+
+func osCpuInfoName() string {
+       modelName := ""
+       cpuMHz := ""
+
+       // The 512-byte buffer is enough to hold the contents of CPU0
+       buf := make([]byte, 512)
+       err := readLinuxProcCPUInfo(buf)
+       if err != nil {
+               return ""
+       }
+
+       scanner := bufio.NewScanner(bytes.NewReader(buf))
+       for scanner.Scan() {
+               line := scanner.Text()
+               if !strings.Contains(line, ":") {
+                       continue
+               }
+
+               field := strings.SplitN(line, ": ", 2)
+               switch strings.TrimSpace(field[0]) {
+               case "Model Name", "model name":
+                       modelName = field[1]
+               case "CPU MHz", "cpu MHz":
+                       cpuMHz = field[1]
+               }
+       }
+
+       if modelName == "" {
+               return ""
+       }
+
+       if cpuMHz == "" {
+               return modelName
+       }
+
+       // The modelName field already contains the frequency information,
+       // so the cpuMHz field information is not needed.
+       // modelName filed example:
+       //      Intel(R) Core(TM) i7-10700 CPU @ 2.90GHz
+       f := [...]string{"GHz", "MHz"}
+       for _, v := range f {
+               if strings.Contains(modelName, v) {
+                       return modelName
+               }
+       }
+
+       return modelName + " @ " + cpuMHz + "MHz"
+}

diff --git a/src/internal/sysinfo/cpuinfo_stub.go b/src/internal/sysinfo/cpuinfo_stub.go
new file mode 100644 (file)
index 0000000..5dcfed1
--- /dev/null
+++ b/src/internal/sysinfo/cpuinfo_stub.go
@@ -0,0 +1,11 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !linux
+
+package sysinfo
+
+func osCpuInfoName() string {
+       return ""
+}

diff --git a/src/internal/sysinfo/sysinfo.go b/src/internal/sysinfo/sysinfo.go
index 961be7abaeebcde789cf3410a0b7473669909a69..6a29ad2bc10ffeabd12dbe9938cd56dddd0d6318 100644 (file)
--- a/src/internal/sysinfo/sysinfo.go
+++ b/src/internal/sysinfo/sysinfo.go
@@ -7,25 +7,29 @@
 package sysinfo
 
 import (
-       internalcpu "internal/cpu"
+       "internal/cpu"
        "sync"
 )
 
-type cpuInfo struct {
+var cpuInfo struct {
        once sync.Once
        name string
 }
 
-var CPU cpuInfo
-
-func (cpu *cpuInfo) Name() string {
-       cpu.once.Do(func() {
+func CPUName() string {
+       cpuInfo.once.Do(func() {
                // Try to get the information from internal/cpu.
-               if name := internalcpu.Name(); name != "" {
-                       cpu.name = name
+               if name := cpu.Name(); name != "" {
+                       cpuInfo.name = name
                        return
                }
+
                // TODO(martisch): use /proc/cpuinfo and /sys/devices/system/cpu/ on Linux as fallback.
+               if name := osCpuInfoName(); name != "" {
+                       cpuInfo.name = name
+                       return
+               }
        })
-       return cpu.name
+
+       return cpuInfo.name
 }

diff --git a/src/testing/benchmark.go b/src/testing/benchmark.go
index e40859599349d87ebeeacb379c631e3ad295d29a..c9012ea0acb3d4e2b2f648e00f6851472590e7bf 100644 (file)
--- a/src/testing/benchmark.go
+++ b/src/testing/benchmark.go
@@ -251,7 +251,7 @@ func (b *B) run() {
                if b.importPath != "" {
                        fmt.Fprintf(b.w, "pkg: %s\n", b.importPath)
                }
-               if cpu := sysinfo.CPU.Name(); cpu != "" {
+               if cpu := sysinfo.CPUName(); cpu != "" {
                        fmt.Fprintf(b.w, "cpu: %s\n", cpu)
                }
        })
@@ -668,7 +668,7 @@ func (b *B) Run(name string, f func(b *B)) bool {
                        if b.importPath != "" {
                                fmt.Printf("pkg: %s\n", b.importPath)
                        }
-                       if cpu := sysinfo.CPU.Name(); cpu != "" {
+                       if cpu := sysinfo.CPUName(); cpu != "" {
                                fmt.Printf("cpu: %s\n", cpu)
                        }
                })