diff mbox series

[2/2] generic/251: check min and max length and minlen for FSTRIM

Message ID 20231026032151.GJ3195650@frogsfrogsfrogs (mailing list archive)
State New, archived
Headers show
Series [1/2] generic/251: don't snapshot $here during a test | expand

Commit Message

Darrick J. Wong Oct. 26, 2023, 3:21 a.m. UTC 
From: Darrick J. Wong <djwong@kernel.org>

Every now and then, this test fails with the following output when
running against my development tree when configured with an 8k fs block
size:

Comments

Zorro Lang Oct. 27, 2023, 12:12 p.m. UTC | #1 
On Wed, Oct 25, 2023 at 08:21:51PM -0700, Darrick J. Wong wrote:
> From: Darrick J. Wong <djwong@kernel.org>
> 
> Every now and then, this test fails with the following output when
> running against my development tree when configured with an 8k fs block
> size:
> 
> --- a/tests/generic/251.out	2023-07-11 12:18:21.624971186 -0700
> +++ b/tests/generic/251.out.bad	2023-10-15 20:54:44.636000000 -0700
> @@ -1,2 +1,4677 @@
>  QA output created by 251
>  Running the test: done.
> +fstrim: /opt: FITRIM ioctl failed: Invalid argument
> +fstrim: /opt: FITRIM ioctl failed: Invalid argument
> ...
> +fstrim: /opt: FITRIM ioctl failed: Invalid argument
> 
> Dumping the exact fstrim command lines to seqres.full produces this at
> the end:
> 
> /usr/sbin/fstrim -m 32544k -o 30247k -l 4k /opt
> /usr/sbin/fstrim -m 32544k -o 30251k -l 4k /opt
> ...
> /usr/sbin/fstrim -m 32544k -o 30255k -l 4k /opt
> 
> The count of failure messages is the same as the count as the "-l 4k"
> fstrim invocations.  Since this is an 8k-block filesystem, the -l
> parameter is clearly incorrect.  The test computes random -m and -l
> options.
> 
> Therefore, create helper functions to guess at the minimum and maximum
> length and minlen parameters that can be used with the fstrim program.
> In the inner loop of the test, make sure that our choices for -m and -l
> fall within those constraints.
> 
> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
> ---

Good to me, although I need to add some spaces to those lines with "+", to
merge it successfully :)

Reviewed-by: Zorro Lang <zlang@redhat.com>

>  tests/generic/251 |   59 ++++++++++++++++++++++++++++++++++++++++++++++-------
>  1 file changed, 51 insertions(+), 8 deletions(-)
> 
> diff --git a/tests/generic/251 b/tests/generic/251
> index 3b807df5fa..b7a15f9189 100755
> --- a/tests/generic/251
> +++ b/tests/generic/251
> @@ -53,14 +53,46 @@ _fail()
>  	kill $mypid 2> /dev/null
>  }
>  
> -_guess_max_minlen()
> +# Set FSTRIM_{MIN,MAX}_MINLEN to the lower and upper bounds of the -m(inlen)
> +# parameter to fstrim on the scratch filesystem.
> +set_minlen_constraints()
>  {
> -	mmlen=100000
> -	while [ $mmlen -gt 1 ]; do
> +	local mmlen
> +
> +	for ((mmlen = 100000; mmlen > 0; mmlen /= 2)); do
>  		$FSTRIM_PROG -l $(($mmlen*2))k -m ${mmlen}k $SCRATCH_MNT &> /dev/null && break
> -		mmlen=$(($mmlen/2))
>  	done
> -	echo $mmlen
> +	test $mmlen -gt 0 || \
> +		_notrun "could not determine maximum FSTRIM minlen param"
> +	FSTRIM_MAX_MINLEN=$mmlen
> +
> +	for ((mmlen = 1; mmlen < FSTRIM_MAX_MINLEN; mmlen *= 2)); do
> +		$FSTRIM_PROG -l $(($mmlen*2))k -m ${mmlen}k $SCRATCH_MNT &> /dev/null && break
> +	done
> +	test $mmlen -le $FSTRIM_MAX_MINLEN || \
> +		_notrun "could not determine minimum FSTRIM minlen param"
> +	FSTRIM_MIN_MINLEN=$mmlen
> +}
> +
> +# Set FSTRIM_{MIN,MAX}_LEN to the lower and upper bounds of the -l(ength)
> +# parameter to fstrim on the scratch filesystem.
> +set_length_constraints()
> +{
> +	local mmlen
> +
> +	for ((mmlen = 100000; mmlen > 0; mmlen /= 2)); do
> +		$FSTRIM_PROG -l ${mmlen}k $SCRATCH_MNT &> /dev/null && break
> +	done
> +	test $mmlen -gt 0 || \
> +		_notrun "could not determine maximum FSTRIM length param"
> +	FSTRIM_MAX_LEN=$mmlen
> +
> +	for ((mmlen = 1; mmlen < FSTRIM_MAX_LEN; mmlen *= 2)); do
> +		$FSTRIM_PROG -l ${mmlen}k $SCRATCH_MNT &> /dev/null && break
> +	done
> +	test $mmlen -le $FSTRIM_MAX_LEN || \
> +		_notrun "could not determine minimum FSTRIM length param"
> +	FSTRIM_MIN_LEN=$mmlen
>  }
>  
>  ##
> @@ -70,13 +102,24 @@ _guess_max_minlen()
>  ##
>  fstrim_loop()
>  {
> +	set_minlen_constraints
> +	set_length_constraints
> +	echo "MINLEN max=$FSTRIM_MAX_MINLEN min=$FSTRIM_MIN_MINLEN" >> $seqres.full
> +	echo "LENGTH max=$FSTRIM_MAX_LEN min=$FSTRIM_MIN_LEN" >> $seqres.full
> +
>  	trap "_destroy_fstrim; exit \$status" 2 15
>  	fsize=$(_discard_max_offset_kb "$SCRATCH_MNT" "$SCRATCH_DEV")
> -	mmlen=$(_guess_max_minlen)
>  
>  	while true ; do
> -		step=$((RANDOM*$RANDOM+4))
> -		minlen=$(((RANDOM*($RANDOM%2+1))%$mmlen))
> +		while true; do
> +			step=$((RANDOM*$RANDOM+4))
> +			test "$step" -ge "$FSTRIM_MIN_LEN" && break
> +		done
> +		while true; do
> +			minlen=$(( (RANDOM * (RANDOM % 2 + 1)) % FSTRIM_MAX_MINLEN ))
> +			test "$minlen" -ge "$FSTRIM_MIN_MINLEN" && break
> +		done
> +
>  		start=$RANDOM
>  		if [ $((RANDOM%10)) -gt 7 ]; then
>  			$FSTRIM_PROG $SCRATCH_MNT &
>
diff mbox series

Patch

--- a/tests/generic/251.out	2023-07-11 12:18:21.624971186 -0700
+++ b/tests/generic/251.out.bad	2023-10-15 20:54:44.636000000 -0700
@@ -1,2 +1,4677 @@ 
 QA output created by 251
 Running the test: done.
+fstrim: /opt: FITRIM ioctl failed: Invalid argument
+fstrim: /opt: FITRIM ioctl failed: Invalid argument
...
+fstrim: /opt: FITRIM ioctl failed: Invalid argument

Dumping the exact fstrim command lines to seqres.full produces this at
the end:

/usr/sbin/fstrim -m 32544k -o 30247k -l 4k /opt
/usr/sbin/fstrim -m 32544k -o 30251k -l 4k /opt
...
/usr/sbin/fstrim -m 32544k -o 30255k -l 4k /opt

The count of failure messages is the same as the count as the "-l 4k"
fstrim invocations.  Since this is an 8k-block filesystem, the -l
parameter is clearly incorrect.  The test computes random -m and -l
options.

Therefore, create helper functions to guess at the minimum and maximum
length and minlen parameters that can be used with the fstrim program.
In the inner loop of the test, make sure that our choices for -m and -l
fall within those constraints.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
---
 tests/generic/251 |   59 ++++++++++++++++++++++++++++++++++++++++++++++-------
 1 file changed, 51 insertions(+), 8 deletions(-)

diff --git a/tests/generic/251 b/tests/generic/251
index 3b807df5fa..b7a15f9189 100755
--- a/tests/generic/251
+++ b/tests/generic/251
@@ -53,14 +53,46 @@  _fail()
 	kill $mypid 2> /dev/null
 }
 
-_guess_max_minlen()
+# Set FSTRIM_{MIN,MAX}_MINLEN to the lower and upper bounds of the -m(inlen)
+# parameter to fstrim on the scratch filesystem.
+set_minlen_constraints()
 {
-	mmlen=100000
-	while [ $mmlen -gt 1 ]; do
+	local mmlen
+
+	for ((mmlen = 100000; mmlen > 0; mmlen /= 2)); do
 		$FSTRIM_PROG -l $(($mmlen*2))k -m ${mmlen}k $SCRATCH_MNT &> /dev/null && break
-		mmlen=$(($mmlen/2))
 	done
-	echo $mmlen
+	test $mmlen -gt 0 || \
+		_notrun "could not determine maximum FSTRIM minlen param"
+	FSTRIM_MAX_MINLEN=$mmlen
+
+	for ((mmlen = 1; mmlen < FSTRIM_MAX_MINLEN; mmlen *= 2)); do
+		$FSTRIM_PROG -l $(($mmlen*2))k -m ${mmlen}k $SCRATCH_MNT &> /dev/null && break
+	done
+	test $mmlen -le $FSTRIM_MAX_MINLEN || \
+		_notrun "could not determine minimum FSTRIM minlen param"
+	FSTRIM_MIN_MINLEN=$mmlen
+}
+
+# Set FSTRIM_{MIN,MAX}_LEN to the lower and upper bounds of the -l(ength)
+# parameter to fstrim on the scratch filesystem.
+set_length_constraints()
+{
+	local mmlen
+
+	for ((mmlen = 100000; mmlen > 0; mmlen /= 2)); do
+		$FSTRIM_PROG -l ${mmlen}k $SCRATCH_MNT &> /dev/null && break
+	done
+	test $mmlen -gt 0 || \
+		_notrun "could not determine maximum FSTRIM length param"
+	FSTRIM_MAX_LEN=$mmlen
+
+	for ((mmlen = 1; mmlen < FSTRIM_MAX_LEN; mmlen *= 2)); do
+		$FSTRIM_PROG -l ${mmlen}k $SCRATCH_MNT &> /dev/null && break
+	done
+	test $mmlen -le $FSTRIM_MAX_LEN || \
+		_notrun "could not determine minimum FSTRIM length param"
+	FSTRIM_MIN_LEN=$mmlen
 }
 
 ##
@@ -70,13 +102,24 @@  _guess_max_minlen()
 ##
 fstrim_loop()
 {
+	set_minlen_constraints
+	set_length_constraints
+	echo "MINLEN max=$FSTRIM_MAX_MINLEN min=$FSTRIM_MIN_MINLEN" >> $seqres.full
+	echo "LENGTH max=$FSTRIM_MAX_LEN min=$FSTRIM_MIN_LEN" >> $seqres.full
+
 	trap "_destroy_fstrim; exit \$status" 2 15
 	fsize=$(_discard_max_offset_kb "$SCRATCH_MNT" "$SCRATCH_DEV")
-	mmlen=$(_guess_max_minlen)
 
 	while true ; do
-		step=$((RANDOM*$RANDOM+4))
-		minlen=$(((RANDOM*($RANDOM%2+1))%$mmlen))
+		while true; do
+			step=$((RANDOM*$RANDOM+4))
+			test "$step" -ge "$FSTRIM_MIN_LEN" && break
+		done
+		while true; do
+			minlen=$(( (RANDOM * (RANDOM % 2 + 1)) % FSTRIM_MAX_MINLEN ))
+			test "$minlen" -ge "$FSTRIM_MIN_MINLEN" && break
+		done
+
 		start=$RANDOM
 		if [ $((RANDOM%10)) -gt 7 ]; then
 			$FSTRIM_PROG $SCRATCH_MNT &