validate: add simple CPU count autodetection

Summary: Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org>

Test Plan: ran ./validate on linux

Reviewers: austin

Reviewed By: austin

Subscribers: phaskell, simonmar, relrod, ezyang, carter

Differential Revision: https://phabricator.haskell.org/D146

1 files changed, 27 insertions, 5 deletions

diff --git a/validate b/validate
index 7a7b1256a5..8ea9eace1c 100755
--- a/validate
+++ b/validate
@@ -88,6 +88,32 @@ check_packages () {
     echo "== End $1 package check"
 }
 
+detect_cpu_count () {
+    if [ "$CPUS" = "" ]; then
+        # Windows standard environment variable
+        CPUS="$NUMBER_OF_PROCESSORS"
+    fi
+
+    if [ "$CPUS" = "" ]; then
+        # Linux
+        CPUS=`getconf _NPROCESSORS_ONLN 2>/dev/null`
+    fi
+
+    if [ "$CPUS" = "" ]; then
+        # FreeBSD
+        CPUS=`getconf NPROCESSORS_ONLN 2>/dev/null`
+    fi
+
+    if [ "$CPUS" = "" ]; then
+        # nothing helped
+        CPUS="1"
+    fi
+
+    echo "using ${CPUS} CPUs" >&2
+}
+
+detect_cpu_count
+
 if ! [ -d testsuite ]
 then
     echo 'Could not find the testsuite for validation' >&2
@@ -95,11 +121,7 @@ then
 fi
 
 if [ "$THREADS" = "" ]; then
-    if [ "$CPUS" = "" ]; then
-        threads=2
-    else
-        threads=$(($CPUS + 1)) # `expr $CPUS + 1`
-    fi
+    threads=$(($CPUS + 1)) # `expr $CPUS + 1`
 else
     threads="$THREADS"
 fi