trace: Add ftrace tracing backend
This patch adds a ftrace tracing backend which sends trace event to
ftrace marker file. You can effectively compare qemu trace data and
kernel(especially, kvm.ko when using KVM) trace data.
The ftrace backend is restricted to Linux only.
To try out the ftrace backend:
$ ./configure --trace-backend=ftrace
$ make
if you use KVM, enable kvm events in ftrace:
# sudo echo 1 > /sys/kernel/debug/tracing/events/kvm/enable
After running qemu by root user, you can get the trace:
# cat /sys/kernel/debug/tracing/trace
Signed-off-by: Eiichi Tsukata <eiichi.tsukata.xh@hitachi.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
diff --git a/configure b/configure
index c4d85ba..e818e8b 100755
--- a/configure
+++ b/configure
@@ -4004,6 +4004,14 @@
echo "CONFIG_TRACE_SYSTEMTAP=y" >> $config_host_mak
fi
fi
+if test "$trace_backend" = "ftrace"; then
+ if test "$linux" = "yes" ; then
+ echo "CONFIG_TRACE_FTRACE=y" >> $config_host_mak
+ trace_default=no
+ else
+ feature_not_found "ftrace(trace backend)"
+ fi
+fi
echo "CONFIG_TRACE_FILE=$trace_file" >> $config_host_mak
if test "$trace_default" = "yes"; then
echo "CONFIG_TRACE_DEFAULT=y" >> $config_host_mak
