From 63dc30e6496ef877b52ae197f4d4ab8d303b474b Mon Sep 17 00:00:00 2001 From: Masami Hiramatsu Date: Fri, 26 May 2017 13:44:54 +0900 Subject: [PATCH] selftests/ftrace: Add a testcase for many kprobe events 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. Link: http://lkml.kernel.org/r/149577388470.11702.11832460851769204511.stgit@devbox Signed-off-by: Masami Hiramatsu Suggested-by: Steven Rostedt Signed-off-by: Steven Rostedt (VMware) --- .../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 0000000000000..f4d1ff785d67d --- /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" -- 2.39.5