On Tue,  2 May 2023 11:18:21 +0900
"Masami Hiramatsu (Google)" [off-list ref] wrote:

From: Masami Hiramatsu (Google) <mhiramat@kernel.org>

Add the '$$args' meta fetch argument for function-entry probe events. This

Hmm, couldn't we just use $args ? That would be different from $arg1,
$arg2, etc.

The $$ to me would be either the bash pid of current, or perhaps it would
be just to use a dollar sign. I don't see the precedence of $$args being a
"full expand".

-- Steve

will be expanded to the all arguments of the function and the tracepoint
using BTF function argument information.

e.g.
 #  echo 'p vfs_read $$args' >> dynamic_events
 #  echo 'f vfs_write $$args' >> dynamic_events
 #  echo 't sched_overutilized_tp $$args' >> dynamic_events
 # cat dynamic_events
p:kprobes/p_vfs_read_0 vfs_read file=file buf=buf count=count pos=pos
f:fprobes/vfs_write__entry vfs_write file=file buf=buf count=count pos=pos
t:tracepoints/sched_overutilized_tp sched_overutilized_tp rd=rd overutilized=overutilized

Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
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