Commit bdd7e3d6 authored May 26, 2017 by Masami Hiramatsu Committed by Steven Rostedt (VMware) May 26, 2017

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 <mhiramat@kernel.org>
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

parent c93f5cf5

tools/testing/selftests/ftrace/test.d/kprobe/multiple_kprobes.tc

0 → 100644

+21 −0

Original line number	Diff line number	Diff line
		#!/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"

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