On Mon, 1 Feb 2021, Stefan Hajnoczi wrote:
It is possible to repeat the --trace option to specify multiple
patterns. This may be preferrable to users who do not want to create a
file with a list of patterns.
Suggested-by: BALATON Zoltan <bala...@eik.bme.hu>
Signed-off-by: Stefan Hajnoczi <stefa...@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <phi...@redhat.com>
Message-id: 20210112165859.225534-2-stefa...@redhat.com
Signed-off-by: Stefan Hajnoczi <stefa...@redhat.com>
---
docs/devel/tracing.rst | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)
diff --git a/docs/devel/tracing.rst b/docs/devel/tracing.rst
index af395e957d..e8f9b82c5e 100644
--- a/docs/devel/tracing.rst
+++ b/docs/devel/tracing.rst
@@ -22,10 +22,15 @@ events::
This output comes from the "log" trace backend that is enabled by default when
``./configure --enable-trace-backends=BACKENDS`` was not explicitly specified.
-More than one trace event pattern can be specified by providing a file
-instead::
+Multiple patterns can be specified by repeating the ``--trace`` option::
+
+ $ qemu --trace "kvm_*" --trace "virtio_*" ...
Does that actually work? I've always used -trace enable="pattern1" -trace
enable="pattern2" Not sure if omitting enable= is the same.
Regards,
BALATON Zoltan
+
+When patterns are used frequently it is more convenient to store them in a
+file to avoid long command-line options::
$ echo "memory_region_ops_*" >/tmp/events
+ $ echo "kvm_*" >>/tmp/events
$ qemu --trace events=/tmp/events ...
Trace events
--
2.29.2
