trace: add "-trace enable=..."
Allow enabling events without going through a file, for example:
qemu-system-x86_64 -trace bdrv_aio_writev -trace bdrv_aio_readv
or with globbing too:
qemu-system-x86_64 -trace 'bdrv_aio_*'
if an appropriate backend is enabled (simple, stderr, ftrace).
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Message-id: 1452174932-28657-6-git-send-email-den@openvz.org
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
diff --git a/qemu-options.hx b/qemu-options.hx
index cbb4590..35dc725 100644
--- a/qemu-options.hx
+++ b/qemu-options.hx
@@ -3544,7 +3544,7 @@
files from @var{datadir}.
ETEXI
DEF("trace", HAS_ARG, QEMU_OPTION_trace,
- "-trace [events=<file>][,file=<file>]\n"
+ "-trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n"
" specify tracing options\n",
QEMU_ARCH_ALL)
STEXI
@@ -3556,6 +3556,14 @@
Specify tracing options.
@table @option
+@item [enable=]@var{pattern}
+Immediately enable events matching @var{pattern}.
+The file must contain one event name (as listed in the @file{trace-events} file)
+per line; globbing patterns are accepted too. This option is only
+available if QEMU has been compiled with the @var{simple}, @var{stderr}
+or @var{ftrace} tracing backend. To specify multiple events or patterns,
+specify the @option{-trace} option multiple times.
+
@item events=@var{file}
Immediately enable events listed in @var{file}.
The file must contain one event name (as listed in the @file{trace-events} file)
