[Qemu-devel] [PATCH 6/6] trace: enable tracing in qemu-img

["Denis V. Lunev" <den@openvz.org>]

The command will work this way:
    qemu-img --trace qcow2* create -f qcow2 1.img 64G

Signed-off-by: Denis V. Lunev <den@openvz.org>
Suggested by: Daniel P. Berrange <berrange@redhat.com>
CC: Eric Blake <eblake@redhat.com>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
CC: Kevin Wolf <kwolf@redhat.com>
---
 Makefile      |  2 +-
 qemu-img.c    | 18 +++++++++++++++++-
 qemu-img.texi |  2 ++
 3 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/Makefile b/Makefile
index 49b9650..327c04f 100644
--- a/Makefile
+++ b/Makefile
@@ -546,7 +546,7 @@ qemu.1: qemu-doc.texi qemu-options.texi qemu-monitor.texi qemu-monitor-info.texi
 	  "  GEN   $@")
 qemu.1: qemu-option-trace.texi
 
-qemu-img.1: qemu-img.texi qemu-img-cmds.texi
+qemu-img.1: qemu-img.texi qemu-option-trace.texi qemu-img-cmds.texi
 	$(call quiet-command, \
 	  perl -Ww -- $(SRC_PATH)/scripts/texi2pod.pl $< qemu-img.pod && \
 	  $(POD2MAN) --section=1 --center=" " --release=" " qemu-img.pod > $@, \
diff --git a/qemu-img.c b/qemu-img.c
index d22ebdf..128579f 100644
--- a/qemu-img.c
+++ b/qemu-img.c
@@ -31,6 +31,7 @@
 #include "qemu/config-file.h"
 #include "qemu/option.h"
 #include "qemu/error-report.h"
+#include "qemu/log.h"
 #include "qom/object_interfaces.h"
 #include "sysemu/sysemu.h"
 #include "sysemu/block-backend.h"
@@ -38,6 +39,7 @@
 #include "block/blockjob.h"
 #include "block/qapi.h"
 #include "crypto/init.h"
+#include "trace/control.h"
 #include <getopt.h>
 
 #define QEMU_IMG_VERSION "qemu-img version " QEMU_VERSION QEMU_PKGVERSION \
@@ -92,6 +94,8 @@ static void QEMU_NORETURN help(void)
            "\n"
            "    '-h', '--help'       display this help and exit\n"
            "    '-V', '--version'    output version information and exit\n"
+           "    '-T', '--trace'      [[enable=]<pattern>][,events=<file>][,file=<file>]\n"
+           "                         specify tracing options\n"
            "\n"
            "Command syntax:\n"
 #define DEF(option, callback, arg_string)        \
@@ -3476,10 +3480,12 @@ int main(int argc, char **argv)
     const img_cmd_t *cmd;
     const char *cmdname;
     Error *local_error = NULL;
+    char *trace_file = NULL;
     int c;
     static const struct option long_options[] = {
         {"help", no_argument, 0, 'h'},
         {"version", no_argument, 0, 'V'},
+        {"trace", required_argument, NULL, 'T'},
         {0, 0, 0, 0}
     };
 
@@ -3505,8 +3511,9 @@ int main(int argc, char **argv)
 
     qemu_add_opts(&qemu_object_opts);
     qemu_add_opts(&qemu_source_opts);
+    qemu_add_opts(&qemu_trace_opts);
 
-    while ((c = getopt_long(argc, argv, "+hV", long_options, NULL)) != -1) {
+    while ((c = getopt_long(argc, argv, "+hVT:", long_options, NULL)) != -1) {
         switch (c) {
         case 'h':
             help();
@@ -3514,6 +3521,9 @@ int main(int argc, char **argv)
         case 'V':
             printf(QEMU_IMG_VERSION);
             return 0;
+        case 'T':
+            trace_file = trace_opt_parse(optarg, trace_file);
+            break;
         }
     }
 
@@ -3527,6 +3537,12 @@ int main(int argc, char **argv)
     argv += optind;
     optind = 1;
 
+    if (!trace_init_backends()) {
+        exit(1);
+    }
+    trace_init_file(trace_file);
+    qemu_set_log(LOG_TRACE);
+
     /* find the command */
     for (cmd = img_cmds; cmd->name != NULL; cmd++) {
         if (!strcmp(cmdname, cmd->name)) {
diff --git a/qemu-img.texi b/qemu-img.texi
index 5a47810..aa974b6 100644
--- a/qemu-img.texi
+++ b/qemu-img.texi
@@ -22,6 +22,8 @@ Standard options:
 Display this help and exit
 @item -V, --version
 Display version information and exit
+@item -T, --trace [events=@var{file}][,file=@var{file}]
+@include qemu-option-trace.texi
 @end table
 
 The following commands are supported:
-- 
2.5.0