Fix userfaultfd_hugetlb on hosts which have more than 64 cpus.
---------------------------
running userfaultfd_hugetlb
---------------------------
invalid MiB
Usage: <MiB> <bounces>
[FAIL]
Via userfaultfd.c we can know, hugetlb_size needs to meet hugetlb_size >=
nr_cpus * hugepage_size. hugepage_size is often 2M, so when host cpus >
64, it requires more than 128M.
Changes since v1:
- update changelog/comments and variable name to make code more easier to
read/understand(stolen from Mike Kravetz)
Link: http://lkml.kernel.org/r/20180302024356.83359-1-zhijianx...@intel.com
Signed-off-by: Li Zhijian <zhijianx...@intel.com>
Cc: Shuah Khan <sh...@kernel.org>
Cc: SeongJae Park <sj38.p...@gmail.com>
Cc: Philippe Ombredanne <pombreda...@nexb.com>
Cc: Aneesh Kumar K.V <aneesh.ku...@linux.vnet.ibm.com>
Cc: Mike Kravetz <mike.krav...@oracle.com>
Signed-off-by: Andrew Morton <a...@linux-foundation.org>
---
tools/testing/selftests/vm/run_vmtests | 25 +++++++++++++++++--------
1 file changed, 17 insertions(+), 8 deletions(-)
diff --git a/tools/testing/selftests/vm/run_vmtests
b/tools/testing/selftests/vm/run_vmtests
index d2561895a021a..22d5646738302 100755
--- a/tools/testing/selftests/vm/run_vmtests
+++ b/tools/testing/selftests/vm/run_vmtests
@@ -2,25 +2,33 @@
# SPDX-License-Identifier: GPL-2.0
#please run as root
-#we need 256M, below is the size in kB
-needmem=262144
mnt=./huge
exitcode=0
-#get pagesize and freepages from /proc/meminfo
+#get huge pagesize and freepages from /proc/meminfo
while read name size unit; do
if [ "$name" = "HugePages_Free:" ]; then
freepgs=$size
fi
if [ "$name" = "Hugepagesize:" ]; then
- pgsize=$size
+ hpgsize_KB=$size
fi
done < /proc/meminfo
+# Simple hugetlbfs tests have a hardcoded minimum requirement of
+# huge pages totaling 256MB (262144KB) in size. The userfaultfd
+# hugetlb test requires a minimum of 2 * nr_cpus huge pages. Take
+# both of these requirements into account and attempt to increase
+# number of huge pages available.
+nr_cpus=$(nproc)
+hpgsize_MB=$((hpgsize_KB / 1024))
+half_ufd_size_MB=$((((nr_cpus * hpgsize_MB + 127) / 128) * 128))
+needmem_KB=$((half_ufd_size_MB * 2 * 1024))
+
#set proper nr_hugepages
-if [ -n "$freepgs" ] && [ -n "$pgsize" ]; then
+if [ -n "$freepgs" ] && [ -n "$hpgsize_KB" ]; then
nr_hugepgs=`cat /proc/sys/vm/nr_hugepages`
- needpgs=`expr $needmem / $pgsize`
+ needpgs=$((needmem_KB / hpgsize_KB))
tries=2
while [ $tries -gt 0 ] && [ $freepgs -lt $needpgs ]; do
lackpgs=$(( $needpgs - $freepgs ))
@@ -107,8 +115,9 @@ fi
echo "---------------------------"
echo "running userfaultfd_hugetlb"
echo "---------------------------"
-# 256MB total huge pages == 128MB src and 128MB dst
-./userfaultfd hugetlb 128 32 $mnt/ufd_test_file
+# Test requires source and destination huge pages. Size of source
+# (half_ufd_size_MB) is passed as argument to test.
+./userfaultfd hugetlb $half_ufd_size_MB 32 $mnt/ufd_test_file
if [ $? -ne 0 ]; then
echo "[FAIL]"
exitcode=1
--
2.11.0
