This patch adds an optional command line switch '-trace' to specify the
filename to write traces to, when qemu starts.
Eg, If compiled with the 'simple' trace backend,
[t...@system]$ qemu -trace FILENAME IMAGE
Allows the binary traces to be written to FILENAME instead of the option
set at config-time.
Also, this adds monitor sub-command 'set' to trace-file commands to
dynamically change trace log file at runtime.
Eg,
(qemu)trace-file set FILENAME
This allows one to set trace outputs to FILENAME from the default
specified at startup.
Signed-off-by: Prerna Saxena <pre...@linux.vnet.ibm.com>
---
monitor.c | 6 ++++++
qemu-monitor.hx | 6 +++---
qemu-options.hx | 11 +++++++++++
simpletrace.c | 41 ++++++++++++++++++++++++++++++++---------
tracetool | 1 +
vl.c | 22 ++++++++++++++++++++++
6 files changed, 75 insertions(+), 12 deletions(-)
diff --git a/monitor.c b/monitor.c
index 1e35a6b..8e2a3a6 100644
--- a/monitor.c
+++ b/monitor.c
@@ -544,6 +544,7 @@ static void do_change_trace_event_state(Monitor *mon, const
QDict *qdict)
static void do_trace_file(Monitor *mon, const QDict *qdict)
{
const char *op = qdict_get_try_str(qdict, "op");
+ const char *arg = qdict_get_try_str(qdict, "arg");
if (!op) {
st_print_trace_file_status((FILE *)mon, &monitor_fprintf);
@@ -553,8 +554,13 @@ static void do_trace_file(Monitor *mon, const QDict *qdict)
st_set_trace_file_enabled(false);
} else if (!strcmp(op, "flush")) {
st_flush_trace_buffer();
+ } else if (!strcmp(op, "set")) {
+ if (arg) {
+ st_set_trace_file(arg);
+ }
} else {
monitor_printf(mon, "unexpected argument \"%s\"\n", op);
+ monitor_printf(mon, "Options are: [on | off| flush| set FILENAME]");
}
}
#endif
diff --git a/qemu-monitor.hx b/qemu-monitor.hx
index 25887bd..adfaf2b 100644
--- a/qemu-monitor.hx
+++ b/qemu-monitor.hx
@@ -276,9 +276,9 @@ ETEXI
{
.name = "trace-file",
- .args_type = "op:s?",
- .params = "op [on|off|flush]",
- .help = "open, close, or flush trace file",
+ .args_type = "op:s?,arg:F?",
+ .params = "on|off|flush|set [arg]",
+ .help = "open, close, or flush trace file, or set a new file
name",
.mhandler.cmd = do_trace_file,
},
diff --git a/qemu-options.hx b/qemu-options.hx
index d1d2272..aea9675 100644
--- a/qemu-options.hx
+++ b/qemu-options.hx
@@ -2223,6 +2223,17 @@ Normally QEMU loads a configuration file from
@var{sysconfdir}/qemu.conf and
@var{sysconfdir}/targ...@var{arch}.conf on startup. The @code{-nodefconfig}
option will prevent QEMU from loading these configuration files at startup.
ETEXI
+#ifdef CONFIG_SIMPLE_TRACE
+DEF("trace", HAS_ARG, QEMU_OPTION_trace,
+ "-trace\n"
+ " Specify a trace file to log traces to\n",
+ QEMU_ARCH_ALL)
+STEXI
+...@item -trace
+...@findex -trace
+Specify a trace file to log output traces to.
+ETEXI
+#endif
HXCOMM This is the last statement. Insert new options before this line!
STEXI
diff --git a/simpletrace.c b/simpletrace.c
index 71110b3..5812fe9 100644
--- a/simpletrace.c
+++ b/simpletrace.c
@@ -20,25 +20,48 @@ enum {
static TraceRecord trace_buf[TRACE_BUF_LEN];
static unsigned int trace_idx;
static FILE *trace_fp;
-static bool trace_file_enabled = true;
+static char *trace_file_name = NULL;
+static bool trace_file_enabled = false;
void st_print_trace_file_status(FILE *stream, int (*stream_printf)(FILE
*stream, const char *fmt, ...))
{
- stream_printf(stream, "Trace file \"" CONFIG_TRACE_FILE "\" %s.\n",
- getpid(), trace_file_enabled ? "on" : "off");
+ stream_printf(stream, "Trace file \"%s\" %s.\n",
+ trace_file_name, trace_file_enabled ? "on" : "off");
}
static bool open_trace_file(void)
{
- char *filename;
+ trace_fp = fopen(trace_file_name, "w");
+ return trace_fp != NULL;
+}
- if (asprintf(&filename, CONFIG_TRACE_FILE, getpid()) < 0) {
- return false;
+/**
+ * set_trace_file : To set the name of a trace file.
+ * @file : pointer to the name to be set.
+ * If NULL, set to the default name-<pid> set at config time.
+ */
+bool st_set_trace_file(const char *file)
+{
+ if (trace_file_enabled) {
+ st_set_trace_file_enabled(false);
}
- trace_fp = fopen(filename, "w");
- free(filename);
- return trace_fp != NULL;
+ if (trace_file_name) {
+ free(trace_file_name);
+ }
+
+ if (!file) {
+ if (asprintf(&trace_file_name, CONFIG_TRACE_FILE, getpid()) < 0) {
+ return false;
+ }
+ } else {
+ if (asprintf(&trace_file_name, "%s", file) < 0) {
+ return false;
+ }
+ }
+
+ st_set_trace_file_enabled(true);
+ return true;
}
static void flush_trace_file(void)
diff --git a/tracetool b/tracetool
index ac832af..5b979f5 100755
--- a/tracetool
+++ b/tracetool
@@ -158,6 +158,7 @@ void st_print_trace_events(FILE *stream, int
(*stream_printf)(FILE *stream, cons
void st_print_trace_file_status(FILE *stream, int (*stream_printf)(FILE
*stream, const char *fmt, ...));
void st_flush_trace_buffer(void);
void st_set_trace_file_enabled(bool enable);
+bool st_set_trace_file(const char *file);
void change_trace_event_state(const char *tname, bool tstate);
EOF
diff --git a/vl.c b/vl.c
index 920717a..6d68e38 100644
--- a/vl.c
+++ b/vl.c
@@ -47,6 +47,10 @@
#include <dirent.h>
#include <netdb.h>
#include <sys/select.h>
+#ifdef CONFIG_SIMPLE_TRACE
+#include "trace.h"
+#endif
+
#ifdef CONFIG_BSD
#include <sys/stat.h>
#if defined(__FreeBSD__) || defined(__FreeBSD_kernel__) ||
defined(__DragonFly__)
@@ -1822,6 +1826,9 @@ int main(int argc, char **argv, char **envp)
int show_vnc_port = 0;
int defconfig = 1;
+#ifdef CONFIG_SIMPLE_TRACE
+ char *trace_file = NULL;
+#endif
atexit(qemu_run_exit_notifiers);
error_set_progname(argv[0]);
@@ -2590,6 +2597,12 @@ int main(int argc, char **argv, char **envp)
}
xen_mode = XEN_ATTACH;
break;
+#ifdef CONFIG_SIMPLE_TRACE
+ case QEMU_OPTION_trace:
+ trace_file = (char *) qemu_malloc(strlen(optarg) + 1);
+ strcpy(trace_file, optarg);
+ break;
+#endif
case QEMU_OPTION_readconfig:
{
int ret = qemu_read_config_file(optarg);
@@ -2633,6 +2646,15 @@ int main(int argc, char **argv, char **envp)
data_dir = CONFIG_QEMU_DATADIR;
}
+#ifdef CONFIG_SIMPLE_TRACE
+ /*
+ * Set the trace file name, if specified.
+ */
+ st_set_trace_file(trace_file);
+ if (trace_file) {
+ qemu_free(trace_file);
+ }
+#endif
/*
* Default to max_cpus = smp_cpus, in case the user doesn't
* specify a max_cpus value.
--
1.6.2.5
--
Prerna Saxena
Linux Technology Centre,
IBM Systems and Technology Lab,
Bangalore, India
