selftests: vm: Try harder to allocate huge pages
If we need to increase the number of huge pages, drop caches first
to reduce fragmentation and then check that we actually allocated
as many as we wanted. Retry once if that doesn't work.
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
diff --git a/tools/testing/selftests/vm/run_vmtests b/tools/testing/selftests/vm/run_vmtests
index 9179ce8..97ed1b2 100755
--- a/tools/testing/selftests/vm/run_vmtests
+++ b/tools/testing/selftests/vm/run_vmtests
@@ -20,13 +20,26 @@
if [ -n "$freepgs" ] && [ -n "$pgsize" ]; then
nr_hugepgs=`cat /proc/sys/vm/nr_hugepages`
needpgs=`expr $needmem / $pgsize`
- if [ $freepgs -lt $needpgs ]; then
+ tries=2
+ while [ $tries -gt 0 ] && [ $freepgs -lt $needpgs ]; do
lackpgs=$(( $needpgs - $freepgs ))
+ echo 3 > /proc/sys/vm/drop_caches
echo $(( $lackpgs + $nr_hugepgs )) > /proc/sys/vm/nr_hugepages
if [ $? -ne 0 ]; then
echo "Please run this test as root"
exit 1
fi
+ while read name size unit; do
+ if [ "$name" = "HugePages_Free:" ]; then
+ freepgs=$size
+ fi
+ done < /proc/meminfo
+ tries=$((tries - 1))
+ done
+ if [ $freepgs -lt $needpgs ]; then
+ printf "Not enough huge pages available (%d < %d)\n" \
+ $freepgs $needpgs
+ exit 1
fi
else
echo "no hugetlbfs support in kernel?"
