| Message ID | 20240904065908.1009086-6-svens@linux.ibm.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | add function arguments to ftrace | expand |
On 2024/9/4 14:58, Sven Schnelle wrote: > Add a config option to disable/enable function argument > printing support during runtime. > > Signed-off-by: Sven Schnelle <svens@linux.ibm.com> > --- > kernel/trace/Kconfig | 12 ++++++++++++ > 1 file changed, 12 insertions(+) > > diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig > index 721c3b221048..8b9b6cdf39ac 100644 > --- a/kernel/trace/Kconfig > +++ b/kernel/trace/Kconfig > @@ -242,6 +242,18 @@ config FUNCTION_GRAPH_RETVAL > enable it via the trace option funcgraph-retval. > See Documentation/trace/ftrace.rst > > +config FUNCTION_TRACE_ARGS > + bool "Kernel Function Tracer Arguments" > + depends on HAVE_FUNCTION_ARG_ACCESS_API > + depends on DEBUG_INFO_BTF && BPF_SYSCALL Nice feature! Just a nit, DEBUG_INFO_BTF currently depends on BPF_SYSCALL, so BPF_SYSCALL may not be necessary here. This feature also doesn't seem to depend on bpf. > + default n > + help > + Support recording and printing of function arguments when using > + the function tracer or function graph tracer. This feature is off > + by default, and can be enabled via the trace option func-args (for > + the function tracer) and funcgraph-args (for the function graph > + tracer). > + > config DYNAMIC_FTRACE > bool "enable/disable function tracing dynamically" > depends on FUNCTION_TRACER
On Fri, 6 Sep 2024 11:36:11 +0800 Zheng Yejian <zhengyejian@huaweicloud.com> wrote: > On 2024/9/4 14:58, Sven Schnelle wrote: > > Add a config option to disable/enable function argument > > printing support during runtime. > > > > Signed-off-by: Sven Schnelle <svens@linux.ibm.com> > > --- > > kernel/trace/Kconfig | 12 ++++++++++++ > > 1 file changed, 12 insertions(+) > > > > diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig > > index 721c3b221048..8b9b6cdf39ac 100644 > > --- a/kernel/trace/Kconfig > > +++ b/kernel/trace/Kconfig > > @@ -242,6 +242,18 @@ config FUNCTION_GRAPH_RETVAL > > enable it via the trace option funcgraph-retval. > > See Documentation/trace/ftrace.rst > > > > +config FUNCTION_TRACE_ARGS > > + bool "Kernel Function Tracer Arguments" > > + depends on HAVE_FUNCTION_ARG_ACCESS_API > > + depends on DEBUG_INFO_BTF && BPF_SYSCALL > > Nice feature! > > Just a nit, DEBUG_INFO_BTF currently depends on BPF_SYSCALL, > so BPF_SYSCALL may not be necessary here. This feature > also doesn't seem to depend on bpf. Indeed. Sven, you can check the PROBE_EVENTS_BTF_ARGS as an example. config PROBE_EVENTS_BTF_ARGS depends on HAVE_FUNCTION_ARG_ACCESS_API depends on FPROBE_EVENTS || KPROBE_EVENTS depends on DEBUG_INFO_BTF && BPF_SYSCALL bool "Support BTF function arguments for probe events" Thank you, > > > + default n > > + help > > + Support recording and printing of function arguments when using > > + the function tracer or function graph tracer. This feature is off > > + by default, and can be enabled via the trace option func-args (for > > + the function tracer) and funcgraph-args (for the function graph > > + tracer). > > + > > config DYNAMIC_FTRACE > > bool "enable/disable function tracing dynamically" > > depends on FUNCTION_TRACER > > -- > Thanks, > Zheng Yejian > >
Masami Hiramatsu (Google) <mhiramat@kernel.org> writes: > On Fri, 6 Sep 2024 11:36:11 +0800 > Zheng Yejian <zhengyejian@huaweicloud.com> wrote: > >> On 2024/9/4 14:58, Sven Schnelle wrote: >> > Add a config option to disable/enable function argument >> > printing support during runtime. >> > >> > Signed-off-by: Sven Schnelle <svens@linux.ibm.com> >> > --- >> > kernel/trace/Kconfig | 12 ++++++++++++ >> > 1 file changed, 12 insertions(+) >> > >> > diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig >> > index 721c3b221048..8b9b6cdf39ac 100644 >> > --- a/kernel/trace/Kconfig >> > +++ b/kernel/trace/Kconfig >> > @@ -242,6 +242,18 @@ config FUNCTION_GRAPH_RETVAL >> > enable it via the trace option funcgraph-retval. >> > See Documentation/trace/ftrace.rst >> > >> > +config FUNCTION_TRACE_ARGS >> > + bool "Kernel Function Tracer Arguments" >> > + depends on HAVE_FUNCTION_ARG_ACCESS_API >> > + depends on DEBUG_INFO_BTF && BPF_SYSCALL >> >> Nice feature! >> >> Just a nit, DEBUG_INFO_BTF currently depends on BPF_SYSCALL, >> so BPF_SYSCALL may not be necessary here. This feature >> also doesn't seem to depend on bpf. > > Indeed. Sven, you can check the PROBE_EVENTS_BTF_ARGS as > an example. > > config PROBE_EVENTS_BTF_ARGS > depends on HAVE_FUNCTION_ARG_ACCESS_API > depends on FPROBE_EVENTS || KPROBE_EVENTS > depends on DEBUG_INFO_BTF && BPF_SYSCALL > bool "Support BTF function arguments for probe events" Now i'm confused - Zheng wrote that DEBUG_INFO_BTF depends on BPF_SYSCALL. I just verified that. So i could just remove BPF_SYSCALL from the dependencies - but your example also has BPF_SYSCALL listed. Regards Sven
On Mon, 09 Sep 2024 10:16:55 +0200 Sven Schnelle <svens@linux.ibm.com> wrote: > Masami Hiramatsu (Google) <mhiramat@kernel.org> writes: > > > On Fri, 6 Sep 2024 11:36:11 +0800 > > Zheng Yejian <zhengyejian@huaweicloud.com> wrote: > > > >> On 2024/9/4 14:58, Sven Schnelle wrote: > >> > Add a config option to disable/enable function argument > >> > printing support during runtime. > >> > > >> > Signed-off-by: Sven Schnelle <svens@linux.ibm.com> > >> > --- > >> > kernel/trace/Kconfig | 12 ++++++++++++ > >> > 1 file changed, 12 insertions(+) > >> > > >> > diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig > >> > index 721c3b221048..8b9b6cdf39ac 100644 > >> > --- a/kernel/trace/Kconfig > >> > +++ b/kernel/trace/Kconfig > >> > @@ -242,6 +242,18 @@ config FUNCTION_GRAPH_RETVAL > >> > enable it via the trace option funcgraph-retval. > >> > See Documentation/trace/ftrace.rst > >> > > >> > +config FUNCTION_TRACE_ARGS > >> > + bool "Kernel Function Tracer Arguments" > >> > + depends on HAVE_FUNCTION_ARG_ACCESS_API > >> > + depends on DEBUG_INFO_BTF && BPF_SYSCALL > >> > >> Nice feature! > >> > >> Just a nit, DEBUG_INFO_BTF currently depends on BPF_SYSCALL, > >> so BPF_SYSCALL may not be necessary here. This feature > >> also doesn't seem to depend on bpf. > > > > Indeed. Sven, you can check the PROBE_EVENTS_BTF_ARGS as > > an example. > > > > config PROBE_EVENTS_BTF_ARGS > > depends on HAVE_FUNCTION_ARG_ACCESS_API > > depends on FPROBE_EVENTS || KPROBE_EVENTS > > depends on DEBUG_INFO_BTF && BPF_SYSCALL > > bool "Support BTF function arguments for probe events" > > Now i'm confused - Zheng wrote that DEBUG_INFO_BTF depends on > BPF_SYSCALL. I just verified that. So i could just remove BPF_SYSCALL > from the dependencies - but your example also has BPF_SYSCALL listed. Ah, sorry for confusion. In this case, just need DEBUG_INFO_BTF. Hmm, I think I also need to remove BPF_SYSCALL. Thanks, > > Regards > Sven
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig index 721c3b221048..8b9b6cdf39ac 100644 --- a/kernel/trace/Kconfig +++ b/kernel/trace/Kconfig @@ -242,6 +242,18 @@ config FUNCTION_GRAPH_RETVAL enable it via the trace option funcgraph-retval. See Documentation/trace/ftrace.rst +config FUNCTION_TRACE_ARGS + bool "Kernel Function Tracer Arguments" + depends on HAVE_FUNCTION_ARG_ACCESS_API + depends on DEBUG_INFO_BTF && BPF_SYSCALL + default n + help + Support recording and printing of function arguments when using + the function tracer or function graph tracer. This feature is off + by default, and can be enabled via the trace option func-args (for + the function tracer) and funcgraph-args (for the function graph + tracer). + config DYNAMIC_FTRACE bool "enable/disable function tracing dynamically" depends on FUNCTION_TRACER
Add a config option to disable/enable function argument printing support during runtime. Signed-off-by: Sven Schnelle <svens@linux.ibm.com> --- kernel/trace/Kconfig | 12 ++++++++++++ 1 file changed, 12 insertions(+)