On Wed, Dec 13, 2023 at 09:40:38AM +0900, Masami Hiramatsu wrote: > Hi Naveen, > > On Tue, 12 Dec 2023 14:26:07 +0530 > Naveen N Rao <[email protected]> wrote: > > > Add a test to exercize cpu hotplug with the function tracer active to > > ensure that sensitive functions in idle path are excluded from being > > traced. This helps catch issues such as the one fixed by commit > > 4b3338aaa74d ("powerpc/ftrace: Fix stack teardown in ftrace_no_trace"). > > > > Signed-off-by: Naveen N Rao <[email protected]> > > --- > > .../ftrace/test.d/ftrace/func_hotplug.tc | 30 +++++++++++++++++++ > > 1 file changed, 30 insertions(+) > > create mode 100644 > > tools/testing/selftests/ftrace/test.d/ftrace/func_hotplug.tc > > > > diff --git a/tools/testing/selftests/ftrace/test.d/ftrace/func_hotplug.tc > > b/tools/testing/selftests/ftrace/test.d/ftrace/func_hotplug.tc > > new file mode 100644 > > index 000000000000..49731a2b5c23 > > --- /dev/null > > +++ b/tools/testing/selftests/ftrace/test.d/ftrace/func_hotplug.tc > > @@ -0,0 +1,30 @@ > > +#!/bin/sh > > +# SPDX-License-Identifier: GPL-2.0 > > +# description: ftrace - function trace across cpu hotplug > > +# requires: function:tracer > > + > > +if ! which nproc ; then > > + nproc() { > > + ls -d /sys/devices/system/cpu/cpu[0-9]* | wc -l > > + } > > +fi > > + > > +NP=`nproc` > > + > > +if [ $NP -eq 1 ] ;then > > + echo "We can not test cpu hotplug in UP environment" > > + exit_unresolved > > +fi > > This looks good, but can you find the 2nd online CPU before > this test? > I mean, there is a case that cpu1 is already offlined and others > like cpu2 is onlined. So we need to use the 2nd online cpu.
Good point, thanks. I will send a v2. - Naveen
