[PATCH AUTOSEL 5.10 046/217] torture: Prevent jitter processes from delaying failed run

Sasha Levin
2020-12-23T03:09:50Z

From: "Paul E. McKenney" <paulmck@kernel.org>

[ Upstream commit c64659ef29e3901be0900ec6fb0485fa3dbdcfd8 ]

Even when the kernel panics and qemu dies, runs with jitter enabled will
continue uselessly until the jitter.sh processes terminate. This can
be annoying if a planned one-hour run instead dies during boot.

This commit therefore kills the jitter.sh processes when the run ends
more than one minute prior to the termination time specified by the
kvm.sh --duration argument or its default.

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
.../selftests/rcutorture/bin/kvm-test-1-run.sh | 14 ++++++++++++++
tools/testing/selftests/rcutorture/bin/kvm.sh | 5 ++++-
2 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/rcutorture/bin/kvm-test-1-run.sh b/tools/testing/selftests/rcutorture/bin/kvm-test-1-run.sh
index 6dc2b49b85ea0..6544a289a5832 100755
--- a/tools/testing/selftests/rcutorture/bin/kvm-test-1-run.sh
+++ b/tools/testing/selftests/rcutorture/bin/kvm-test-1-run.sh
@@ -223,6 +223,20 @@ do
echo "ps -fp $killpid" >> $resdir/Warnings 2>&1
ps -fp $killpid >> $resdir/Warnings 2>&1
fi
+ # Reduce probability of PID reuse by allowing a one-minute buffer
+ if test $((kruntime + 60)) -lt $seconds && test -s "$resdir/../jitter_pids"
+ then
+ awk < "$resdir/../jitter_pids" '
+ NF > 0 {
+ pidlist = pidlist " " $1;
+ n++;
+ }
+ END {
+ if (n > 0) {
+ print "kill " pidlist;
+ }
+ }' | sh
+ fi
else
echo ' ---' `date`: "Kernel done"
fi
diff --git a/tools/testing/selftests/rcutorture/bin/kvm.sh b/tools/testing/selftests/rcutorture/bin/kvm.sh
index 6eb1d3f6524d5..5ad3882563ce6 100755
--- a/tools/testing/selftests/rcutorture/bin/kvm.sh
+++ b/tools/testing/selftests/rcutorture/bin/kvm.sh
@@ -459,8 +459,11 @@ function dump(first, pastlast, batchnum)
print "if test -n \"$needqemurun\""
print "then"
print "\techo ---- Starting kernels. `date` | tee -a " rd "log";
- for (j = 0; j < njitter; j++)
+ print "\techo > " rd "jitter_pids"
+ for (j = 0; j < njitter; j++) {
print "\tjitter.sh " j " " dur " " ja[2] " " ja[3] "&"
+ print "\techo $! >> " rd "jitter_pids"
+ }
print "\twait"
print "\techo ---- All kernel runs complete. `date` | tee -a " rd "log";
print "else"
--
2.27.0