| Message ID | 20220209162430.286578-1-krzysztof.kozlowski@canonical.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | selftests/ftrace: Do not trace do_softirq because of PREEMPT_RT | expand |
On 2/9/22 9:24 AM, Krzysztof Kozlowski wrote: > The PREEMPT_RT patchset does not use soft IRQs thus trying to filter for > do_softirq fails for such kernel: > > echo do_softirq > ftracetest: 81: echo: echo: I/O error > > Choose some other externally visible function for the test. > > Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com> > > --- > > I understand that the failure does not exist on mainline kernel (only > with PREEMPT_RT patchset) but the change does not harm it. > > If it is not suitable alone, please consider it for RT patchset. > --- > .../selftests/ftrace/test.d/ftrace/func_set_ftrace_file.tc | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/tools/testing/selftests/ftrace/test.d/ftrace/func_set_ftrace_file.tc b/tools/testing/selftests/ftrace/test.d/ftrace/func_set_ftrace_file.tc > index e96e279e0533..1d0c7601865f 100644 > --- a/tools/testing/selftests/ftrace/test.d/ftrace/func_set_ftrace_file.tc > +++ b/tools/testing/selftests/ftrace/test.d/ftrace/func_set_ftrace_file.tc > @@ -19,7 +19,7 @@ fail() { # mesg > > FILTER=set_ftrace_filter > FUNC1="schedule" > -FUNC2="do_softirq" > +FUNC2="_printk" > > ALL_FUNCS="#### all functions enabled ####" > > Change looks good to me. Reviewed-by: Shuah Khan <skhan@linuxfoundation.org> thanks, -- Shuah
On 10/02/2022 06:00, Steven Rostedt wrote: > On Wed, 9 Feb 2022 17:24:30 +0100 > Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com> wrote: > >> The PREEMPT_RT patchset does not use soft IRQs thus trying to filter for >> do_softirq fails for such kernel: >> >> echo do_softirq >> ftracetest: 81: echo: echo: I/O error >> >> Choose some other externally visible function for the test. >> >> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com> >> >> --- >> >> I understand that the failure does not exist on mainline kernel (only >> with PREEMPT_RT patchset) but the change does not harm it. >> >> If it is not suitable alone, please consider it for RT patchset. >> --- >> .../selftests/ftrace/test.d/ftrace/func_set_ftrace_file.tc | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/tools/testing/selftests/ftrace/test.d/ftrace/func_set_ftrace_file.tc b/tools/testing/selftests/ftrace/test.d/ftrace/func_set_ftrace_file.tc >> index e96e279e0533..1d0c7601865f 100644 >> --- a/tools/testing/selftests/ftrace/test.d/ftrace/func_set_ftrace_file.tc >> +++ b/tools/testing/selftests/ftrace/test.d/ftrace/func_set_ftrace_file.tc >> @@ -19,7 +19,7 @@ fail() { # mesg >> >> FILTER=set_ftrace_filter >> FUNC1="schedule" >> -FUNC2="do_softirq" >> +FUNC2="_printk" > > The problem with the above, is that it is not guaranteed to trigger (and > probably will not), where as the do_softirq is. The filtering is suppose to > trace something that actually happens. > > How about using: scheduler_tick ? > This works as well. I had impression that the test is only about filtering interface and actual function does not have to hit/trigger. I'll send v2 with scheduler_tick. Best regards, Krzysztof
diff --git a/tools/testing/selftests/ftrace/test.d/ftrace/func_set_ftrace_file.tc b/tools/testing/selftests/ftrace/test.d/ftrace/func_set_ftrace_file.tc index e96e279e0533..1d0c7601865f 100644 --- a/tools/testing/selftests/ftrace/test.d/ftrace/func_set_ftrace_file.tc +++ b/tools/testing/selftests/ftrace/test.d/ftrace/func_set_ftrace_file.tc @@ -19,7 +19,7 @@ fail() { # mesg FILTER=set_ftrace_filter FUNC1="schedule" -FUNC2="do_softirq" +FUNC2="_printk" ALL_FUNCS="#### all functions enabled ####"
The PREEMPT_RT patchset does not use soft IRQs thus trying to filter for do_softirq fails for such kernel: echo do_softirq ftracetest: 81: echo: echo: I/O error Choose some other externally visible function for the test. Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com> --- I understand that the failure does not exist on mainline kernel (only with PREEMPT_RT patchset) but the change does not harm it. If it is not suitable alone, please consider it for RT patchset. --- .../selftests/ftrace/test.d/ftrace/func_set_ftrace_file.tc | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)