docs: update the usage example of "dtrace" backend in tracing.txt

The usage example of dtrace is quite ancient, We have tracetool.py with
different parameters instead of the original tracetool shell script for
a long time, So update the old information.

Signed-off-by: Lin Ma <lma@suse.com>
Message-id: 1441954730-17341-1-git-send-email-lma@suse.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

diff --git a/docs/tracing.txt b/docs/tracing.txt
index 7117c5e7d60a10a0fb4525dce84cb8caa5ec8fc2..3853a6ad8acb03888babfed5817565bace8b58e7 100644 (file)
--- a/docs/tracing.txt
+++ b/docs/tracing.txt
@@ -258,11 +258,11 @@ is generated to make use in scripts more convenient.  This step can also be
 performed manually after a build in order to change the binary name in the .stp
 probes:
 
-    scripts/tracetool --dtrace --stap \
-                      --binary path/to/qemu-binary \
-                      --target-type system \
-                      --target-name x86_64 \
-                      <trace-events >qemu.stp
+    scripts/tracetool.py --backends=dtrace --format=stap \
+                         --binary path/to/qemu-binary \
+                         --target-type system \
+                         --target-name x86_64 \
+                         <trace-events >qemu.stp
 
 == Trace event properties ==