From 42d2ab4803b423ef42ef98bc3e383b2fe25508f9 Mon Sep 17 00:00:00 2001
From: Brad Smith <brad@comstyle.com>
Date: Mon, 3 Feb 2025 19:00:56 -0500
Subject: [PATCH] Retrieve the number of online CPUs on OpenBSD and NetBSD

---
 src/sysinfo.cc | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/src/sysinfo.cc b/src/sysinfo.cc
index eddd430e68..f44f7d3b33 100644
--- a/src/sysinfo.cc
+++ b/src/sysinfo.cc
@@ -153,11 +153,11 @@ ValueUnion GetSysctlImp(std::string const& name) {
   int mib[2];
 
   mib[0] = CTL_HW;
-  if ((name == "hw.ncpu") || (name == "hw.cpuspeed")) {
+  if ((name == "hw.ncpuonline") || (name == "hw.cpuspeed")) {
     ValueUnion buff(sizeof(int));
 
-    if (name == "hw.ncpu") {
-      mib[1] = HW_NCPU;
+    if (name == "hw.ncpuonline") {
+      mib[1] = HW_NCPUONLINE;
     } else {
       mib[1] = HW_CPUSPEED;
     }
@@ -482,7 +482,11 @@ std::string GetSystemName() {
 int GetNumCPUsImpl() {
 #ifdef BENCHMARK_HAS_SYSCTL
   int num_cpu = -1;
+#ifdef HW_NCPUONLINE
+  if (GetSysctl("hw.ncpuonline", &num_cpu)) return num_cpu;
+#else
   if (GetSysctl("hw.ncpu", &num_cpu)) return num_cpu;
+#endif
   PrintErrorAndDie("Err: ", strerror(errno));
 #elif defined(BENCHMARK_OS_WINDOWS)
   SYSTEM_INFO sysinfo;