From 0b1c752b5c40a85d5c749cd30ee6811997a8f71e Mon Sep 17 00:00:00 2001
From: Wayne Zhang <shuowang.zhang@ibm.com>
Date: Fri, 17 Jun 2022 06:55:44 -0400
Subject: [PATCH] zos: implement uv_available_parallelism() (#3650)

Implement uv_available_parallelism() for z/OS by reporting the number of
online cpu using __get_num_online_cpus() from ZOSLIB.
---
 src/unix/core.c | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/src/unix/core.c b/src/unix/core.c
index fd4f34809..54c769f37 100644
--- a/src/unix/core.c
+++ b/src/unix/core.c
@@ -81,7 +81,8 @@ extern char** environ;
 #endif
 
 #if defined(__MVS__)
-#include <sys/ioctl.h>
+# include <sys/ioctl.h>
+# include "zos-sys-info.h"
 #endif
 
 #if defined(__linux__)
@@ -1647,7 +1648,13 @@ unsigned int uv_available_parallelism(void) {
 
   return (unsigned) rc;
 #elif defined(__MVS__)
-  return 1;  /* TODO(bnoordhuis) Read from CSD_NUMBER_ONLINE_CPUS? */
+  int rc;
+
+  rc = __get_num_online_cpus();
+  if (rc < 1)
+    rc = 1;
+
+  return (unsigned) rc;
 #else  /* __linux__ */
   long rc;