12:03 a.m.
Jeff found that device-dax was broken with respect to falling back to
smaller fault granularities. Now that the fixes are upstream ([1], [2]),
add a test to backstop against future regressions and validate
backports.
Note that kernels without device-dax pud-mapping support will always
fail the alignment == 1GiB test. Kernels with the broken fallback
handling will fail the first alignment == 4KiB test.
The test requires an fio binary with support for the "dev-dax" ioengine.
[1]: commit 70b085b06c45 ("device-dax: fix pud fault fallback handling")
[2]: commit 0134ed4fb9e7 ("device-dax: fix pmd/pte fault fallback handling")
Cc: Dave Jiang <dave.jiang(a)intel.com>
Reported-by: Jeff Moyer <jmoyer(a)redhat.com>
Signed-off-by: Dan Williams <dan.j.williams(a)intel.com>
---
test/Makefile.am | 1 +
test/device-dax-fio.sh | 74 ++++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 75 insertions(+)
create mode 100755 test/device-dax-fio.sh
diff --git a/test/Makefile.am b/test/Makefile.am
index 98f444231306..969fe055b35e 100644
--- a/test/Makefile.am
+++ b/test/Makefile.am
@@ -26,6 +26,7 @@ TESTS +=\
dax-dev \
dax.sh \
device-dax \
+ device-dax-fio.sh \
mmap.sh
check_PROGRAMS +=\
diff --git a/test/device-dax-fio.sh b/test/device-dax-fio.sh
new file mode 100755
index 000000000000..ab620b67027f
--- /dev/null
+++ b/test/device-dax-fio.sh
@@ -0,0 +1,74 @@
+#!/bin/bash
+NDCTL="../ndctl/ndctl"
+rc=77
+
+set -e
+
+err() {
+ echo "test/device-dax-fio.sh: failed at line $1"
+ exit $rc
+}
+
+check_min_kver()
+{
+ local ver="$1"
+ : "${KVER:=$(uname -r)}"
+
+ [ -n "$ver" ] || return 1
+ [[ "$ver" == "$(echo -e "$ver\n$KVER" | sort -V | head
-1)" ]]
+}
+
+check_min_kver "4.11" || { echo "kernel $KVER may lack latest device-dax
fixes"; exit $rc; }
+
+set -e
+trap 'err $LINENO' ERR
+
+if ! fio --enghelp | grep -q "dev-dax"; then
+ echo "fio lacks dev-dax engine"
+ exit 77
+fi
+
+dev=$(./dax-dev)
+for align in 4k 2m 1g
+do
+ json=$($NDCTL create-namespace -m dax -a $align -f -e $dev)
+ chardev=$(echo $json | jq -r ". | select(.mode == \"dax\") |
.daxregion.devices[0].chardev")
+ if [ align = "1g" ]; then
+ bs="1g"
+ else
+ bs="2m"
+ fi
+
+ cat > fio.job <<- EOF
+ [global]
+ ioengine=dev-dax
+ direct=0
+ filename=/dev/${chardev}
+ verify=crc32c
+ bs=${bs}
+
+ [write]
+ rw=write
+ runtime=5
+
+ [read]
+ stonewall
+ rw=read
+ runtime=5
+ EOF
+
+ rc=1
+ fio fio.job 2>&1 | tee fio.log
+
+ if grep -q "fio.*got signal" fio.log; then
+ echo "test/device-dax-fio.sh: failed with align: $align"
+ exit 1
+ fi
+
+ # revert namespace to raw mode
+ json=$($NDCTL create-namespace -m raw -f -e $dev)
+ mode=$(echo $json | jq -r ".mode")
+ [ $mode != "memory" ] && echo "fail: $LINENO" &&
exit 1
+done
+
+exit 0