pkg/sysinfo: unify NumCPU implementations

Use a single NumCPU implementation, so that the godoc string and the
fallback to runtime.NumCPU can be maintained in one place.

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>

common/pkg/sysinfo/numcpu.go

@@ -1,13 +1,13 @@
-//go:build !linux && !windows
-// +build !linux,!windows
-
 package sysinfo
 
-import (
-	"runtime"
-)
+import "runtime"
 
-// NumCPU returns the number of CPUs
+// NumCPU returns the number of CPUs. On Linux and Windows, it returns
+// the number of CPUs which are currently online. On other platforms,
+// it returns [runtime.NumCPU].
 func NumCPU() int {
+	if ncpu := numCPU(); ncpu > 0 {
+		return ncpu
+	}
 	return runtime.NumCPU()
 }

common/pkg/sysinfo/numcpu_linux.go

@@ -4,7 +4,6 @@
 package sysinfo
 
 import (
-	"runtime"
 	"unsafe"
 
 	"golang.org/x/sys/unix"
@@ -34,11 +33,3 @@ func numCPU() int {
 	}
 	return ncpu
 }
-
-// NumCPU returns the number of CPUs which are currently online
-func NumCPU() int {
-	if ncpu := numCPU(); ncpu > 0 {
-		return ncpu
-	}
-	return runtime.NumCPU()
-}

common/pkg/sysinfo/numcpu_other.go

@@ -0,0 +1,10 @@
+//go:build !linux && !windows
+// +build !linux,!windows
+
+package sysinfo
+
+import "runtime"
+
+func numCPU() int {
+	return runtime.NumCPU()
+}

common/pkg/sysinfo/numcpu_windows.go

@@ -4,7 +4,6 @@
 package sysinfo
 
 import (
-	"runtime"
 	"unsafe"
 
 	"golang.org/x/sys/windows"
@@ -28,11 +27,3 @@ func numCPU() int {
 	ncpu := int(popcnt(uint64(mask)))
 	return ncpu
 }
-
-// NumCPU returns the number of CPUs which are currently online
-func NumCPU() int {
-	if ncpu := numCPU(); ncpu > 0 {
-		return ncpu
-	}
-	return runtime.NumCPU()
-}