this patch is to fix running userfaultfd_hugetlb failed on the host which has
more than 64 cpus
---------------------------
running userfaultfd_hugetlb
---------------------------
invalid MiB
Usage: <MiB> <bounces>
[FAIL]
From userfaultfd.c we can know, hugetlb_size need to meet hugetlb_size >= nr_cpus * hugepage_size
hugepage_size is often 2M, so when host cpus > 64, it requires more than 128M.
Signed-off-by: Li Zhijian <[email protected]>
---
tools/testing/selftests/vm/run_vmtests | 13 +++++++++----
1 file changed, 9 insertions(+), 4 deletions(-)
diff --git a/tools/testing/selftests/vm/run_vmtests b/tools/testing/selftests/vm/run_vmtests
index d2561895a021a..c440fb972afe9 100755
--- a/tools/testing/selftests/vm/run_vmtests
+++ b/tools/testing/selftests/vm/run_vmtests
@@ -2,8 +2,6 @@
# 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
@@ -17,6 +15,13 @@ while read name size unit; do
fi
done < /proc/meminfo
+nr_cpus=$(nproc)
+pgsize_MB=$((pgsize/1024))
+# rule: nr_cpus * pgsize_MB <= hugetlb_size(round to 128M for testing)
+hugetlb_size=$((((nr_cpus*pgsize_MB+127)/128)*128))
+# needmem depends on the nr_cpus, below is the size in kB
+needmem=$((hugetlb_size*2*1024))
+
#set proper nr_hugepages
if [ -n "$freepgs" ] && [ -n "$pgsize" ]; then
nr_hugepgs=`cat /proc/sys/vm/nr_hugepages`
@@ -107,8 +112,8 @@ fi
echo "---------------------------"
echo "running userfaultfd_hugetlb"
echo "---------------------------"
-# 256MB total huge pages == 128MB src and 128MB dst
-./userfaultfd hugetlb 128 32 $mnt/ufd_test_file
+# 256MB total huge pages == 128MB src and 128MB dst when nr_cpus <= 64
+./userfaultfd hugetlb $hugetlb_size 32 $mnt/ufd_test_file
if [ $? -ne 0 ]; then
echo "[FAIL]"
exitcode=1
--
2.11.0
On 03/01/2018 06:43 PM, Li Zhijian wrote:
> this patch is to fix running userfaultfd_hugetlb failed on the host which has
> more than 64 cpus
> ---------------------------
> running userfaultfd_hugetlb
> ---------------------------
> invalid MiB
> Usage: <MiB> <bounces>
> [FAIL]
>
> From userfaultfd.c we can know, hugetlb_size need to meet hugetlb_size >= nr_cpus * hugepage_size
> hugepage_size is often 2M, so when host cpus > 64, it requires more than 128M.
>
> Signed-off-by: Li Zhijian <[email protected]>
Thanks for fixing this.
> ---
> tools/testing/selftests/vm/run_vmtests | 13 +++++++++----
> 1 file changed, 9 insertions(+), 4 deletions(-)
>
> diff --git a/tools/testing/selftests/vm/run_vmtests b/tools/testing/selftests/vm/run_vmtests
> index d2561895a021a..c440fb972afe9 100755
> --- a/tools/testing/selftests/vm/run_vmtests
> +++ b/tools/testing/selftests/vm/run_vmtests
> @@ -2,8 +2,6 @@
> # SPDX-License-Identifier: GPL-2.0
> #please run as root
>
> -#we need 256M, below is the size in kB
> -needmem=262144
> mnt=./huge
> exitcode=0
>
> @@ -17,6 +15,13 @@ while read name size unit; do
> fi
> done < /proc/meminfo
>
> +nr_cpus=$(nproc)
> +pgsize_MB=$((pgsize/1024))
> +# rule: nr_cpus * pgsize_MB <= hugetlb_size(round to 128M for testing)
> +hugetlb_size=$((((nr_cpus*pgsize_MB+127)/128)*128))
> +# needmem depends on the nr_cpus, below is the size in kB
> +needmem=$((hugetlb_size*2*1024))
> +
> #set proper nr_hugepages
> if [ -n "$freepgs" ] && [ -n "$pgsize" ]; then
> nr_hugepgs=`cat /proc/sys/vm/nr_hugepages`
> @@ -107,8 +112,8 @@ fi
> echo "---------------------------"
> echo "running userfaultfd_hugetlb"
> echo "---------------------------"
> -# 256MB total huge pages == 128MB src and 128MB dst
> -./userfaultfd hugetlb 128 32 $mnt/ufd_test_file
> +# 256MB total huge pages == 128MB src and 128MB dst when nr_cpus <= 64
> +./userfaultfd hugetlb $hugetlb_size 32 $mnt/ufd_test_file
> if [ $? -ne 0 ]; then
> echo "[FAIL]"
> exitcode=1
The above changes are functionally OK. But, I think something like the
following may be easier to read/understand. Feel free to use as much or
little as you would like.
--
Mike Kravetz
Signed-off-by: Mike Kravetz <[email protected]>
---
tools/testing/selftests/vm/run_vmtests | 25 +++++++++++++++++--------
1 file changed, 17 insertions(+), 8 deletions(-)
diff --git a/tools/testing/selftests/vm/run_vmtests b/tools/testing/selftests/vm/run_vmtests
index d2561895a021..40671f6739a9 100755
--- a/tools/testing/selftests/vm/run_vmtests
+++ b/tools/testing/selftests/vm/run_vmtests
@@ -2,25 +2,33 @@
# SPDX-License-Identifier: GPL-2.0
#please run as root
-#we need 256M, below is the size in kB
-needmem=262144
mnt=./huge
exitcode=0
-#get pagesize and freepages from /proc/meminfo
+#get huge pagesize and freepages from /proc/meminfo
while read name size unit; do
if [ "$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
--
2.13.6