On Tue, Mar 18, 2025 at 06:20:35PM -0300, Filipe Xavier wrote:
Add new ftrace helpers functions cleanup_tracing, trace_function and check_traced_functions.
Signed-off-by: Filipe Xavier felipeaggger@gmail.com
tools/testing/selftests/livepatch/functions.sh | 49 ++++++++++++++++++++++++++ 1 file changed, 49 insertions(+)
diff --git a/tools/testing/selftests/livepatch/functions.sh b/tools/testing/selftests/livepatch/functions.sh index 15601402dee6567837c2c49ba342eb357e410d18..dea9cc10a3f09662c57c2593cff49423302c8a5c 100644 --- a/tools/testing/selftests/livepatch/functions.sh +++ b/tools/testing/selftests/livepatch/functions.sh @@ -10,6 +10,7 @@ SYSFS_KERNEL_DIR="/sys/kernel" SYSFS_KLP_DIR="$SYSFS_KERNEL_DIR/livepatch" SYSFS_DEBUG_DIR="$SYSFS_KERNEL_DIR/debug" SYSFS_KPROBES_DIR="$SYSFS_DEBUG_DIR/kprobes" +SYSFS_TRACING_DIR="$SYSFS_DEBUG_DIR/tracing" # Kselftest framework requirement - SKIP code is 4 ksft_skip=4 @@ -62,6 +63,9 @@ function push_config() { awk -F'[: ]' '{print "file " $1 " line " $2 " " $4}') FTRACE_ENABLED=$(sysctl --values kernel.ftrace_enabled) KPROBE_ENABLED=$(cat "$SYSFS_KPROBES_DIR/enabled")
- TRACING_ON=$(cat "$SYSFS_TRACING_DIR/tracing_on")
- CURRENT_TRACER=$(cat "$SYSFS_TRACING_DIR/current_tracer")
- FTRACE_FILTER=$(cat "$SYSFS_TRACING_DIR/set_ftrace_filter")
} function pop_config() { @@ -74,6 +78,17 @@ function pop_config() { if [[ -n "$KPROBE_ENABLED" ]]; then echo "$KPROBE_ENABLED" > "$SYSFS_KPROBES_DIR/enabled" fi
- if [[ -n "$TRACING_ON" ]]; then
echo "$TRACING_ON" > "$SYSFS_TRACING_DIR/tracing_on"- fi
- if [[ -n "$CURRENT_TRACER" ]]; then
echo "$CURRENT_TRACER" > "$SYSFS_TRACING_DIR/current_tracer"- fi
- if [[ -n "$FTRACE_FILTER" ]]; then
echo "$FTRACE_FILTER" \| sed -e "/#### all functions enabled ####/d"> "$SYSFS_TRACING_DIR/set_ftrace_filter"- fi
} function set_dynamic_debug() { @@ -352,3 +367,37 @@ function check_sysfs_value() { die "Unexpected value in $path: $expected_value vs. $value" fi }
+# cleanup_tracing() - stop and clean up function tracing +function cleanup_tracing() {
- echo 0 > "$SYSFS_TRACING_DIR/tracing_on"
- echo "" > "$SYSFS_TRACING_DIR/set_ftrace_filter"
- echo "nop" > "$SYSFS_TRACING_DIR/current_tracer"
- echo "" > "$SYSFS_TRACING_DIR/trace"
+}
+# trace_function(function) - start tracing of a function +# function - to be traced function +function trace_function() {
- local function="$1"; shift
- cleanup_tracing
- echo "function" > "$SYSFS_TRACING_DIR/current_tracer"
- echo "$function" > "$SYSFS_TRACING_DIR/set_ftrace_filter"
- echo 1 > "$SYSFS_TRACING_DIR/tracing_on"
+}
+# check_traced_functions(functions...) - check whether each function appeared in the trace log +# functions - list of functions to be checked +function check_traced_functions() {
- local function
- for function in "$@"; do
if ! grep -q "$function" "$SYSFS_TRACING_DIR/trace" ; then
Small suggestion here: grep on "$function" may find partial string matches, like:
$ echo 'hamburger' | grep 'ham' hamburger
so it's probably safer to user --word-regexp to avoid longer function names inadvertently matching:
$ echo 'hamburger' | grep -w 'ham' $ echo 'ham' | grep -w 'ham' ham
Also, maybe also --fixed-strings for the extra paranoid? Off the top of my head, I don't think any C function characters are special regex (like $ ^ [ ] etc.) so it's probably safe w/o.
-- Joe