Add a testcase to test kprobes via ftrace interface with many concurrent kprobe events. This tries to add many kprobe events (up to 256) on kernel functions. To avoid making ftrace-based kprobes (kprobes on fentry), it skips first N bytes (on x86 N=5, on ppc or arm N=4) of function entry. After that, it enables all those events, disable it, and remove it. Since the unoptimization buffer reclaiming will be delayed, after removing events, it will wait enough time. Signed-off-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx> Suggested-by: Steven Rostedt <rostedt@xxxxxxxxxxx> --- This ensures following bug is fixed and no regression. https://lkml.org/lkml/2017/5/25/218 --- .../ftrace/test.d/kprobe/multiple_kprobes.tc | 21 ++++++++++++++++++++ 1 file changed, 21 insertions(+) create mode 100644 tools/testing/selftests/ftrace/test.d/kprobe/multiple_kprobes.tc diff --git a/tools/testing/selftests/ftrace/test.d/kprobe/multiple_kprobes.tc b/tools/testing/selftests/ftrace/test.d/kprobe/multiple_kprobes.tc new file mode 100644 index 0000000..f4d1ff7 --- /dev/null +++ b/tools/testing/selftests/ftrace/test.d/kprobe/multiple_kprobes.tc @@ -0,0 +1,21 @@ +#!/bin/sh +# description: Register/unregister many kprobe events + +# ftrace fentry skip size depends on the machine architecture. +# Currently HAVE_KPROBES_ON_FTRACE defined on x86 and powerpc +case `uname -m` in + x86_64|i[3456]86) OFFS=5;; + ppc*) OFFS=4;; + *) OFFS=0;; +esac + +echo "Setup up to 256 kprobes" +grep t /proc/kallsyms | cut -f3 -d" " | grep -v .*\\..* | \ +head -n 256 | while read i; do echo p ${i}+${OFFS} ; done > kprobe_events ||: + +echo 1 > events/kprobes/enable +echo 0 > events/kprobes/enable +echo > kprobe_events +echo "Waiting for unoptimizing & freeing" +sleep 5 +echo "Done" -- To unsubscribe from this list: send the line "unsubscribe linux-kselftest" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
