Update objtrace usage in Documentation/trace/events.rst

Posted by renhai_lenovo 2 years, 2 months ago

Documentation: trace/objtrace: Move the line entering the trace
directory to the first step, so that the commands in the first step
can be executed smoothly.

    Signed-off-by: Renhai <rh_king@163.com>

diff --git a/Documentation/trace/events.rst b/Documentation/trace/events.rst
index 52ac8ca8ab64..d5fadf7966de 100644
--- a/Documentation/trace/events.rst
+++ b/Documentation/trace/events.rst
@@ -583,6 +583,7 @@ The following commands are supported:

   .. code-block::

+    # cd /sys/kernel/debug/tracing/
      # echo 'p bio_add_page arg1=$arg1' > ./kprobe_events

   Secondly, we can get the value dynamically based on the object:
@@ -597,7 +598,6 @@ The following commands are supported:
      # echo 'objtrace:add:arg1,0x28:u32:1 if comm == "cat"' >
./events/kprobes/ \
        p_bio_add_page_0/trigger

-     # cd /sys/kernel/debug/tracing/
      # echo 'p bio_add_page arg1=$arg1' > ./kprobe_events
      # echo 'objtrace:add:arg1,0x28:u32:1 if comm == "cat"' >
./events/kprobes/p_bio_add_page_0/trigger

Re: Update objtrace usage in Documentation/trace/events.rst

Posted by Jeff Xie 2 years, 2 months ago

Hi renhai,

On Tue, Oct 31, 2023 at 10:46 AM renhai_lenovo <kean0048@gmail.com> wrote:
>
> Documentation: trace/objtrace: Move the line entering the trace
> directory to the first step, so that the commands in the first step
> can be executed smoothly.
>
>     Signed-off-by: Renhai <rh_king@163.com>
>
> diff --git a/Documentation/trace/events.rst b/Documentation/trace/events.rst
> index 52ac8ca8ab64..d5fadf7966de 100644
> --- a/Documentation/trace/events.rst
> +++ b/Documentation/trace/events.rst
> @@ -583,6 +583,7 @@ The following commands are supported:
>
>    .. code-block::
>
> +    # cd /sys/kernel/debug/tracing/
>       # echo 'p bio_add_page arg1=$arg1' > ./kprobe_events
>
>    Secondly, we can get the value dynamically based on the object:
> @@ -597,7 +598,6 @@ The following commands are supported:
>       # echo 'objtrace:add:arg1,0x28:u32:1 if comm == "cat"' >
> ./events/kprobes/ \
>         p_bio_add_page_0/trigger
>
> -     # cd /sys/kernel/debug/tracing/
>       # echo 'p bio_add_page arg1=$arg1' > ./kprobe_events
>       # echo 'objtrace:add:arg1,0x28:u32:1 if comm == "cat"' >
> ./events/kprobes/p_bio_add_page_0/trigger

Thank you for your interest in the objtrace function. I am currently
busy with other things.
I will come back soon to update this function. When I update it, I
will add your suggestions.

-- 
Thanks,
JeffXie