trace: enable tracing in qemu-nbd
Please note, trace_init_backends() must be called in the final process,
i.e. after daemonization. This is necessary to keep tracing thread in
the proper process.
Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1466174654-30130-6-git-send-email-den@openvz.org
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
diff --git a/qemu-nbd.c b/qemu-nbd.c
index 9519db3..321f02b 100644
--- a/qemu-nbd.c
+++ b/qemu-nbd.c
@@ -27,12 +27,14 @@
#include "qemu/error-report.h"
#include "qemu/config-file.h"
#include "qemu/bswap.h"
+#include "qemu/log.h"
#include "block/snapshot.h"
#include "qapi/util.h"
#include "qapi/qmp/qstring.h"
#include "qom/object_interfaces.h"
#include "io/channel-socket.h"
#include "crypto/init.h"
+#include "trace/control.h"
#include <getopt.h>
#include <libgen.h>
@@ -88,6 +90,8 @@
"General purpose options:\n"
" --object type,id=ID,... define an object such as 'secret' for providing\n"
" passwords and/or encryption keys\n"
+" -T, --trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n"
+" specify tracing options\n"
#ifdef __linux__
"Kernel NBD client support:\n"
" -c, --connect=DEV connect FILE to the local NBD device DEV\n"
@@ -470,7 +474,7 @@
off_t fd_size;
QemuOpts *sn_opts = NULL;
const char *sn_id_or_name = NULL;
- const char *sopt = "hVb:o:p:rsnP:c:dvk:e:f:tl:x:";
+ const char *sopt = "hVb:o:p:rsnP:c:dvk:e:f:tl:x:T:";
struct option lopt[] = {
{ "help", no_argument, NULL, 'h' },
{ "version", no_argument, NULL, 'V' },
@@ -498,6 +502,7 @@
{ "export-name", required_argument, NULL, 'x' },
{ "tls-creds", required_argument, NULL, QEMU_NBD_OPT_TLSCREDS },
{ "image-opts", no_argument, NULL, QEMU_NBD_OPT_IMAGE_OPTS },
+ { "trace", required_argument, NULL, 'T' },
{ NULL, 0, NULL, 0 }
};
int ch;
@@ -518,6 +523,7 @@
const char *tlscredsid = NULL;
bool imageOpts = false;
bool writethrough = true;
+ char *trace_file = NULL;
/* The client thread uses SIGTERM to interrupt the server. A signal
* handler ensures that "qemu-nbd -v -c" exits with a nice status code.
@@ -531,6 +537,7 @@
module_call_init(MODULE_INIT_QOM);
qemu_add_opts(&qemu_object_opts);
+ qemu_add_opts(&qemu_trace_opts);
qemu_init_exec_dir(argv[0]);
while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) {
@@ -703,6 +710,10 @@
case QEMU_NBD_OPT_IMAGE_OPTS:
imageOpts = true;
break;
+ case 'T':
+ g_free(trace_file);
+ trace_file = trace_opt_parse(optarg);
+ break;
}
}
@@ -718,6 +729,12 @@
exit(EXIT_FAILURE);
}
+ if (!trace_init_backends()) {
+ exit(1);
+ }
+ trace_init_file(trace_file);
+ qemu_set_log(LOG_TRACE);
+
if (tlscredsid) {
if (sockpath) {
error_report("TLS is only supported with IPv4/IPv6");