1 files changed, 33 insertions, 0 deletions
diff --git a/Documentation/sphinx/parallel-wrapper.sh b/Documentation/sphinx/parallel-wrapper.sh
new file mode 100644
index 000000000000..7daf5133bdd3
--- /dev/null
+++ b/Documentation/sphinx/parallel-wrapper.sh
@@ -0,0 +1,33 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0+
+#
+# Figure out if we should follow a specific parallelism from the make
+# environment (as exported by scripts/jobserver-exec), or fall back to
+# the "auto" parallelism when "-jN" is not specified at the top-level
+# "make" invocation.
+
+sphinx="$1"
+shift || true
+
+parallel="$PARALLELISM"
+if [ -z "$parallel" ] ; then
+	# If no parallelism is specified at the top-level make, then
+	# fall back to the expected "-jauto" mode that the "htmldocs"
+	# target has had.
+	auto=$(perl -e 'open IN,"'"$sphinx"' --version 2>&1 |";
+			while (<IN>) {
+				if (m/([\d\.]+)/) {
+					print "auto" if ($1 >= "1.7")
+				}
+			}
+			close IN')
+	if [ -n "$auto" ] ; then
+		parallel="$auto"
+	fi
+fi
+# Only if some parallelism has been determined do we add the -jN option.
+if [ -n "$parallel" ] ; then
+	parallel="-j$parallel"
+fi
+
+exec "$sphinx" "$parallel" "$@"