diff options
author | Donglin Peng <dolinux.peng@gmail.com> | 2023-02-21 02:52:42 +0300 |
---|---|---|
committer | Masami Hiramatsu (Google) <mhiramat@kernel.org> | 2023-02-21 02:52:42 +0300 |
commit | 8478cca1e3abd183f309cd9c2491f484acf5d377 (patch) | |
tree | 22623d22350cc9f938a59ddc85b87da6bbb8ffdd /tools | |
parent | 96cd93af794cf3ef83ae1ad7291160029d7b525e (diff) | |
download | linux-8478cca1e3abd183f309cd9c2491f484acf5d377.tar.xz |
tracing/probe: add a char type to show the character value of traced arguments
There are scenes that we want to show the character value of traced
arguments other than a decimal or hexadecimal or string value for debug
convinience. I add a new type named 'char' to do it and a new test case
file named 'kprobe_args_char.tc' to do selftest for char type.
For example:
The to be traced function is 'void demo_func(char type, char *name);', we
can add a kprobe event as follows to show argument values as we want:
echo 'p:myprobe demo_func $arg1:char +0($arg2):char[5]' > kprobe_events
we will get the following trace log:
... myprobe: (demo_func+0x0/0x29) arg1='A' arg2={'b','p','f','1',''}
Link: https://lore.kernel.org/all/20221219110613.367098-1-dolinux.peng@gmail.com/
Signed-off-by: Donglin Peng <dolinux.peng@gmail.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Diffstat (limited to 'tools')
-rw-r--r-- | tools/testing/selftests/ftrace/test.d/kprobe/kprobe_args_char.tc | 47 |
1 files changed, 47 insertions, 0 deletions
diff --git a/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_args_char.tc b/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_args_char.tc new file mode 100644 index 000000000000..285b4770efad --- /dev/null +++ b/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_args_char.tc @@ -0,0 +1,47 @@ +#!/bin/sh +# SPDX-License-Identifier: GPL-2.0 +# description: Kprobe event char type argument +# requires: kprobe_events + +case `uname -m` in +x86_64) + ARG1=%di +;; +i[3456]86) + ARG1=%ax +;; +aarch64) + ARG1=%x0 +;; +arm*) + ARG1=%r0 +;; +ppc64*) + ARG1=%r3 +;; +ppc*) + ARG1=%r3 +;; +s390*) + ARG1=%r2 +;; +mips*) + ARG1=%r4 +;; +*) + echo "Please implement other architecture here" + exit_untested +esac + +: "Test get argument (1)" +echo "p:testprobe tracefs_create_dir arg1=+0(${ARG1}):char" > kprobe_events +echo 1 > events/kprobes/testprobe/enable +echo "p:test $FUNCTION_FORK" >> kprobe_events +grep -qe "testprobe.* arg1='t'" trace + +echo 0 > events/kprobes/testprobe/enable +: "Test get argument (2)" +echo "p:testprobe tracefs_create_dir arg1=+0(${ARG1}):char arg2=+0(${ARG1}):char[4]" > kprobe_events +echo 1 > events/kprobes/testprobe/enable +echo "p:test $FUNCTION_FORK" >> kprobe_events +grep -qe "testprobe.* arg1='t' arg2={'t','e','s','t'}" trace |