diff mbox series

[blktests,v2,2/2] blktests: add Ming Lei's scsi-stress-remove

Message ID 20181213182844.97512-1-dennis@kernel.org (mailing list archive)
State New, archived
Headers show
Series None | expand

Commit Message

Dennis Zhou Dec. 13, 2018, 6:28 p.m. UTC 
This test exposed a race condition with shutting down a request_queue
and the new blkg association. The issue ended up being that while the
request_queue will just start failing requests, blkg destruction sets
the q->root_blkg to %NULL. This caused a NPE when trying to reference
it. So to help prevent this from happening again, integrate Ming's test
into blktests so that it can more easily be ran.

Signed-off-by: Dennis Zhou <dennis@kernel.org>
Cc: Ming Lei <ming.lei@redhat.com>
---
v2:
- Change scheduler retrieving logic based on Ming's comment

 tests/block/022     | 90 +++++++++++++++++++++++++++++++++++++++++++++
 tests/block/022.out |  2 +
 2 files changed, 92 insertions(+)
 create mode 100755 tests/block/022
 create mode 100644 tests/block/022.out

Comments

Ming Lei Dec. 14, 2018, 12:31 a.m. UTC | #1 
On Thu, Dec 13, 2018 at 01:28:44PM -0500, Dennis Zhou wrote:
> This test exposed a race condition with shutting down a request_queue
> and the new blkg association. The issue ended up being that while the
> request_queue will just start failing requests, blkg destruction sets
> the q->root_blkg to %NULL. This caused a NPE when trying to reference
> it. So to help prevent this from happening again, integrate Ming's test
> into blktests so that it can more easily be ran.
> 
> Signed-off-by: Dennis Zhou <dennis@kernel.org>
> Cc: Ming Lei <ming.lei@redhat.com>
> ---
> v2:
> - Change scheduler retrieving logic based on Ming's comment
> 
>  tests/block/022     | 90 +++++++++++++++++++++++++++++++++++++++++++++
>  tests/block/022.out |  2 +
>  2 files changed, 92 insertions(+)
>  create mode 100755 tests/block/022
>  create mode 100644 tests/block/022.out
> 
> diff --git a/tests/block/022 b/tests/block/022
> new file mode 100755
> index 0000000..84336e0
> --- /dev/null
> +++ b/tests/block/022
> @@ -0,0 +1,90 @@
> +#!/bin/bash
> +# SPDX-License-Identifier: GPL-3.0+
> +# Copyright (C) 2018 Ming Lei
> +#
> +# Regression test for patch "blkcg: handle dying request_queue when associating
> +# a blkg"
> +#
> +# This tries to expose the race condition between blkg association and
> +# request_queue shutdown. When a request_queue is shutdown, the corresponding
> +# blkgs are destroyed. Any further associations should fail gracefully and not
> +# cause a kernel panic.
> +
> +. tests/block/rc
> +. common/scsi_debug
> +. common/cgroup
> +
> +DESCRIPTION="test graceful shutdown of scsi_debug devices with running fio jobs"
> +QUICK=1
> +
> +requires() {
> +	_have_cgroup2_controller io && _have_scsi_debug && _have_fio
> +}
> +
> +scsi_debug_stress_remove() {
> +	scsi_debug_path="/sys/bus/pseudo/drivers/scsi_debug"
> +	count=21
> +
> +	runtime=12
> +	nr_fio_jobs=8
> +	scsi_dbg_ndelay=10000
> +
> +	# set higher aio limit
> +	echo 524288 > /proc/sys/fs/aio-max-nr
> +
> +	#figure out the CAN_QUEUE
> +	can_queue=$(((count + 1) * (count / 2) / 2))
> +
> +	rmmod scsi_debug > /dev/null 2>&1
> +	modprobe scsi_debug virtual_gb=128 max_luns=$count \
> +		ndelay=$scsi_dbg_ndelay max_queue=$can_queue
> +
> +	# figure out scsi_debug disks
> +	hosts=$(ls -d /sys/bus/pseudo/drivers/scsi_debug/adapter0/host*)
> +	hostname=$(basename "$hosts")
> +	host=$(echo "$hostname" | grep -o -E '[0-9]+')
> +
> +	sdisks=$(ls -d $scsi_debug_path/adapter*/"$hostname"/target*/*/block/*)
> +	disks=""
> +	for sd in $sdisks; do
> +		disks+="/dev/"$(basename "$sd")
> +		disks+=" "
> +	done
> +
> +	fio_jobs=""
> +	cnt=0
> +	for sd in $disks; do
> +		cnt=$((cnt+1))
> +		fio_jobs=$fio_jobs" --name=job1 --filename=$sd: "
> +		dev_name=$(basename "$sd")
> +		q_path=/sys/block/$dev_name/queue
> +
> +		scheds=($(sed 's/[][]//g' "$q_path/scheduler"))
> +		sched_idx=$((cnt % ${#scheds[@]}))
> +		echo "${scheds[$sched_idx]}" > "$q_path/scheduler"
> +		echo $cnt > "$q_path/../device/queue_depth"
> +	done
> +
> +	fio --rw=randread --size=128G --direct=1 --ioengine=libaio \
> +		--iodepth=2048 --numjobs=$nr_fio_jobs --bs=4k \
> +		--group_reporting=1 --group_reporting=1 --runtime=$runtime \
> +		--loops=10000 "$fio_jobs" > "$FULL" 2>&1 &
> +
> +	sleep 7
> +	for sd in $disks; do
> +		dev_name=$(basename "$sd")
> +		dpath=/sys/block/$dev_name/device
> +		[ -f "$dpath/delete" ] && echo 1 > "$dpath/delete"
> +	done
> +
> +	wait
> +}
> +
> +
> +test() {
> +	echo "Running ${TEST_NAME}"
> +
> +	scsi_debug_stress_remove
> +
> +	echo "Test complete"
> +}
> diff --git a/tests/block/022.out b/tests/block/022.out
> new file mode 100644
> index 0000000..14d43cb
> --- /dev/null
> +++ b/tests/block/022.out
> @@ -0,0 +1,2 @@
> +Running block/022
> +Test complete
> -- 
> 2.17.1
> 

Reviewed-by: Ming Lei <ming.lei@redhat.com>

thanks,
Ming
Omar Sandoval Dec. 19, 2018, 10:49 p.m. UTC | #2 
On Thu, Dec 13, 2018 at 01:28:44PM -0500, Dennis Zhou wrote:
> This test exposed a race condition with shutting down a request_queue
> and the new blkg association. The issue ended up being that while the
> request_queue will just start failing requests, blkg destruction sets
> the q->root_blkg to %NULL. This caused a NPE when trying to reference
> it. So to help prevent this from happening again, integrate Ming's test
> into blktests so that it can more easily be ran.
> 
> Signed-off-by: Dennis Zhou <dennis@kernel.org>
> Cc: Ming Lei <ming.lei@redhat.com>
> ---
> v2:
> - Change scheduler retrieving logic based on Ming's comment
> 
>  tests/block/022     | 90 +++++++++++++++++++++++++++++++++++++++++++++
>  tests/block/022.out |  2 +
>  2 files changed, 92 insertions(+)
>  create mode 100755 tests/block/022
>  create mode 100644 tests/block/022.out
> 
> diff --git a/tests/block/022 b/tests/block/022
> new file mode 100755
> index 0000000..84336e0
> --- /dev/null
> +++ b/tests/block/022
> @@ -0,0 +1,90 @@
> +#!/bin/bash
> +# SPDX-License-Identifier: GPL-3.0+
> +# Copyright (C) 2018 Ming Lei
> +#
> +# Regression test for patch "blkcg: handle dying request_queue when associating
> +# a blkg"
> +#
> +# This tries to expose the race condition between blkg association and
> +# request_queue shutdown. When a request_queue is shutdown, the corresponding
> +# blkgs are destroyed. Any further associations should fail gracefully and not
> +# cause a kernel panic.
> +
> +. tests/block/rc
> +. common/scsi_debug
> +. common/cgroup
> +
> +DESCRIPTION="test graceful shutdown of scsi_debug devices with running fio jobs"
> +QUICK=1
> +
> +requires() {
> +	_have_cgroup2_controller io && _have_scsi_debug && _have_fio
> +}
> +
> +scsi_debug_stress_remove() {
> +	scsi_debug_path="/sys/bus/pseudo/drivers/scsi_debug"
> +	count=21
> +
> +	runtime=12
> +	nr_fio_jobs=8
> +	scsi_dbg_ndelay=10000
> +
> +	# set higher aio limit
> +	echo 524288 > /proc/sys/fs/aio-max-nr
> +
> +	#figure out the CAN_QUEUE
> +	can_queue=$(((count + 1) * (count / 2) / 2))
> +
> +	rmmod scsi_debug > /dev/null 2>&1
> +	modprobe scsi_debug virtual_gb=128 max_luns=$count \
> +		ndelay=$scsi_dbg_ndelay max_queue=$can_queue
> +
> +	# figure out scsi_debug disks
> +	hosts=$(ls -d /sys/bus/pseudo/drivers/scsi_debug/adapter0/host*)
> +	hostname=$(basename "$hosts")
> +	host=$(echo "$hostname" | grep -o -E '[0-9]+')
> +
> +	sdisks=$(ls -d $scsi_debug_path/adapter*/"$hostname"/target*/*/block/*)
> +	disks=""
> +	for sd in $sdisks; do
> +		disks+="/dev/"$(basename "$sd")
> +		disks+=" "
> +	done

blktests has _init_scsi_debug which does all of this for you. And,
block/001 is very similar to this test, just without the fio workload or
changing schedulers. Could you please rework this to be based on
block/001?
Dennis Zhou Dec. 19, 2018, 10:57 p.m. UTC | #3 
On Wed, Dec 19, 2018 at 02:49:42PM -0800, Omar Sandoval wrote:
> On Thu, Dec 13, 2018 at 01:28:44PM -0500, Dennis Zhou wrote:
> > This test exposed a race condition with shutting down a request_queue
> > and the new blkg association. The issue ended up being that while the
> > request_queue will just start failing requests, blkg destruction sets
> > the q->root_blkg to %NULL. This caused a NPE when trying to reference
> > it. So to help prevent this from happening again, integrate Ming's test
> > into blktests so that it can more easily be ran.
> > 
> > Signed-off-by: Dennis Zhou <dennis@kernel.org>
> > Cc: Ming Lei <ming.lei@redhat.com>
> > ---
> > v2:
> > - Change scheduler retrieving logic based on Ming's comment
> > 
> >  tests/block/022     | 90 +++++++++++++++++++++++++++++++++++++++++++++
> >  tests/block/022.out |  2 +
> >  2 files changed, 92 insertions(+)
> >  create mode 100755 tests/block/022
> >  create mode 100644 tests/block/022.out
> > 
> > diff --git a/tests/block/022 b/tests/block/022
> > new file mode 100755
> > index 0000000..84336e0
> > --- /dev/null
> > +++ b/tests/block/022
> > @@ -0,0 +1,90 @@
> > +#!/bin/bash
> > +# SPDX-License-Identifier: GPL-3.0+
> > +# Copyright (C) 2018 Ming Lei
> > +#
> > +# Regression test for patch "blkcg: handle dying request_queue when associating
> > +# a blkg"
> > +#
> > +# This tries to expose the race condition between blkg association and
> > +# request_queue shutdown. When a request_queue is shutdown, the corresponding
> > +# blkgs are destroyed. Any further associations should fail gracefully and not
> > +# cause a kernel panic.
> > +
> > +. tests/block/rc
> > +. common/scsi_debug
> > +. common/cgroup
> > +
> > +DESCRIPTION="test graceful shutdown of scsi_debug devices with running fio jobs"
> > +QUICK=1
> > +
> > +requires() {
> > +	_have_cgroup2_controller io && _have_scsi_debug && _have_fio
> > +}
> > +
> > +scsi_debug_stress_remove() {
> > +	scsi_debug_path="/sys/bus/pseudo/drivers/scsi_debug"
> > +	count=21
> > +
> > +	runtime=12
> > +	nr_fio_jobs=8
> > +	scsi_dbg_ndelay=10000
> > +
> > +	# set higher aio limit
> > +	echo 524288 > /proc/sys/fs/aio-max-nr
> > +
> > +	#figure out the CAN_QUEUE
> > +	can_queue=$(((count + 1) * (count / 2) / 2))
> > +
> > +	rmmod scsi_debug > /dev/null 2>&1
> > +	modprobe scsi_debug virtual_gb=128 max_luns=$count \
> > +		ndelay=$scsi_dbg_ndelay max_queue=$can_queue
> > +
> > +	# figure out scsi_debug disks
> > +	hosts=$(ls -d /sys/bus/pseudo/drivers/scsi_debug/adapter0/host*)
> > +	hostname=$(basename "$hosts")
> > +	host=$(echo "$hostname" | grep -o -E '[0-9]+')
> > +
> > +	sdisks=$(ls -d $scsi_debug_path/adapter*/"$hostname"/target*/*/block/*)
> > +	disks=""
> > +	for sd in $sdisks; do
> > +		disks+="/dev/"$(basename "$sd")
> > +		disks+=" "
> > +	done
> 
> blktests has _init_scsi_debug which does all of this for you. And,
> block/001 is very similar to this test, just without the fio workload or
> changing schedulers. Could you please rework this to be based on
> block/001?

Yeah I can do that. Sorry for not looking at block/001 more closely.

Thanks,
Dennis
diff mbox series

Patch

diff --git a/tests/block/022 b/tests/block/022
new file mode 100755
index 0000000..84336e0
--- /dev/null
+++ b/tests/block/022
@@ -0,0 +1,90 @@ 
+#!/bin/bash
+# SPDX-License-Identifier: GPL-3.0+
+# Copyright (C) 2018 Ming Lei
+#
+# Regression test for patch "blkcg: handle dying request_queue when associating
+# a blkg"
+#
+# This tries to expose the race condition between blkg association and
+# request_queue shutdown. When a request_queue is shutdown, the corresponding
+# blkgs are destroyed. Any further associations should fail gracefully and not
+# cause a kernel panic.
+
+. tests/block/rc
+. common/scsi_debug
+. common/cgroup
+
+DESCRIPTION="test graceful shutdown of scsi_debug devices with running fio jobs"
+QUICK=1
+
+requires() {
+	_have_cgroup2_controller io && _have_scsi_debug && _have_fio
+}
+
+scsi_debug_stress_remove() {
+	scsi_debug_path="/sys/bus/pseudo/drivers/scsi_debug"
+	count=21
+
+	runtime=12
+	nr_fio_jobs=8
+	scsi_dbg_ndelay=10000
+
+	# set higher aio limit
+	echo 524288 > /proc/sys/fs/aio-max-nr
+
+	#figure out the CAN_QUEUE
+	can_queue=$(((count + 1) * (count / 2) / 2))
+
+	rmmod scsi_debug > /dev/null 2>&1
+	modprobe scsi_debug virtual_gb=128 max_luns=$count \
+		ndelay=$scsi_dbg_ndelay max_queue=$can_queue
+
+	# figure out scsi_debug disks
+	hosts=$(ls -d /sys/bus/pseudo/drivers/scsi_debug/adapter0/host*)
+	hostname=$(basename "$hosts")
+	host=$(echo "$hostname" | grep -o -E '[0-9]+')
+
+	sdisks=$(ls -d $scsi_debug_path/adapter*/"$hostname"/target*/*/block/*)
+	disks=""
+	for sd in $sdisks; do
+		disks+="/dev/"$(basename "$sd")
+		disks+=" "
+	done
+
+	fio_jobs=""
+	cnt=0
+	for sd in $disks; do
+		cnt=$((cnt+1))
+		fio_jobs=$fio_jobs" --name=job1 --filename=$sd: "
+		dev_name=$(basename "$sd")
+		q_path=/sys/block/$dev_name/queue
+
+		scheds=($(sed 's/[][]//g' "$q_path/scheduler"))
+		sched_idx=$((cnt % ${#scheds[@]}))
+		echo "${scheds[$sched_idx]}" > "$q_path/scheduler"
+		echo $cnt > "$q_path/../device/queue_depth"
+	done
+
+	fio --rw=randread --size=128G --direct=1 --ioengine=libaio \
+		--iodepth=2048 --numjobs=$nr_fio_jobs --bs=4k \
+		--group_reporting=1 --group_reporting=1 --runtime=$runtime \
+		--loops=10000 "$fio_jobs" > "$FULL" 2>&1 &
+
+	sleep 7
+	for sd in $disks; do
+		dev_name=$(basename "$sd")
+		dpath=/sys/block/$dev_name/device
+		[ -f "$dpath/delete" ] && echo 1 > "$dpath/delete"
+	done
+
+	wait
+}
+
+
+test() {
+	echo "Running ${TEST_NAME}"
+
+	scsi_debug_stress_remove
+
+	echo "Test complete"
+}
diff --git a/tests/block/022.out b/tests/block/022.out
new file mode 100644
index 0000000..14d43cb
--- /dev/null
+++ b/tests/block/022.out
@@ -0,0 +1,2 @@ 
+Running block/022
+Test complete