Monitor Support for 'simple' trace backend
v2 cover Monitor Support for 'simple' trace backend
This is v2 of monitor commands based on Stefan's trace framework :
( http://lists.gnu.org/archive/html/qemu-devel/2010-05/msg02407.html )
This adds the following monitor commands for the 'simple' backend:
- info trace : to view current contents of the trace buffer.
- info tracepoints : to view all available tracepoints and their
state.
- tracepoint NAME on|off: to enable/disable the logging of data from tracepoint 'NAME'.
Changelog :
- Command 'info trace' is used to view current contents of buffer, in place of 'trace'.
- Cleanups
Signature · 5 lines
Prerna Saxena Linux Technology Centre, IBM Systems and Technology Lab, Bangalore, India
RFC PATCH v2 1/3 Export tdb_hash()
For now, I simply export tdb_hash() from qdict.h for use by tracing framework.
Luiz suggested renaming and exporting it from a location other than qdict.h . Would "qemu-common.h" be a better place?
--- qdict.c | 2 +- qdict.h | 2 ++ 2 files changed, 3 insertions(+), 1 deletions(-)
qdict.c +1 -1
@@ -56,7 +56,7 @@ QDict *qobject_to_qdict(const QObject *obj)* tdb_hash(): based on the hash agorithm from gdbm, via tdb * (from module-init-tools) */ -static unsigned int tdb_hash (const char *name) +unsigned int tdb_hash (const char *name) {unsigned value;/* Used to compute the hash value. */ unsigned i;/* Used to cycle through random values. */
qdict.h +2 -0
@@ -59,4 +59,6 @@ int64_t qdict_get_try_int(const QDict *qdict, const char *key, int64_t err_value);const char *qdict_get_try_str (const QDict *qdict,const char *key); +/* Export tdb_hash() for use by trace framework */ +unsigned int tdb_hash (const char *name);#endif /* QDICT_H */
Signature · 10 lines
1.6.2.5 -- Prerna Saxena Linux Technology Centre, IBM Systems and Technology Lab, Bangalore, India
Re: [RFC v2] [PATCH 1/3] Export tdb_hash()
Quoted 4 lines · On Fri, 11 Jun 2010 00:45:58 +0530 Prerna Saxena <[email protected]>…
For now, I simply export
tdb_hash()fromqdict.hfor use by tracing framework.
Luiz suggested renaming and exporting it from a location other thanqdict.h. Would "qemu-common.h" be a better place?
qemu-common.h seems to be about header files, I thought we had a qemu-misc.c
file already. I'd create it if we don't.
RFC PATCH v2 2/3 Monitor command 'info trace'
In reply to Prerna SaxenaThis introduces the monitor command 'info trace' to display current contents of trace buffer.
--- configure | 3 +++ monitor.c | 12 ++++++++++++ qemu-monitor.hx | 4 ++++ simpletrace.c | 12 ++++++++++++ tracetool | 2 ++ 5 files changed, 33 insertions(+), 0 deletions(-)
configure +3 -0
@@ -2302,6 +2302,9 @@ bsd) esac echo "TRACE_BACKEND=$trace_backend" >> $config_host_mak +if test "$trace_backend" = "simple"; then + echo "CONFIG_SIMPLE_TRACE=y" >> $config_host_mak +fi if test "$trace_backend" = "ust"; then LIBS="-lust $LIBS" fi
monitor.c +12 -0
@@ -55,6 +55,9 @@#include "json-streamer.h" #include "json-parser.h" #include "osdep.h" +#ifdef CONFIG_SIMPLE_TRACE +#include "trace.h" +#endif //#define DEBUG //#define DEBUG_COMPLETION
@@ -2780,6 +2783,15 @@ static const mon_cmd_t info_cmds[] = { .help = "show roms", .mhandler.info = do_info_roms, }, +#if defined(CONFIG_SIMPLE_TRACE) + { + .name = "trace", + .args_type = "", + .params = "", + .help = "show current contents of trace buffer", + .mhandler.info = do_info_trace, + }, +#endif { .name = NULL, },
qemu-monitor.hx +4 -0
@@ -114,6 +114,10 @@ show migration status show balloon information @item info qtree show device tree +#ifdef CONFIG_SIMPLE_TRACE +@item info trace +show contents of trace buffer +#endif @end table ETEXI
simpletrace.c +12 -0
@@ -62,3 +62,15 @@ void trace4(TraceEvent event, unsigned long x1, unsigned long x2, unsigned longvoid trace5 (TraceEvent event,unsigned long x1,unsigned long x2,unsigned long x3,unsigned long x4,unsigned long x5) {trace (event, x1, x2, x3, x4, x5); } + +void do_info_trace (Monitor *mon) +{ +unsigned int i, max_idx; + + max_idx = trace_idx ? trace_idx :TRACE_BUF_LEN ; + +for (i=0 ; i<max_idx ;i++) +monitor_printf (mon,"Event %ld : %ld %ld %ld %ld %ld\n" , + trace_buf[i].event, trace_buf[i].x1, trace_buf[i].x2, + trace_buf[i].x3, trace_buf[i].x4, trace_buf[i].x5); +}
tracetool +2 -0
@@ -130,6 +130,7 @@ void trace2(TraceEvent event, unsigned long x1, unsigned long x2); void trace3(TraceEvent event, unsigned long x1, unsigned long x2, unsigned long x3); void trace4(TraceEvent event, unsigned long x1, unsigned long x2, unsigned long x3, unsigned long x4); void trace5(TraceEvent event, unsigned long x1, unsigned long x2, unsigned long x3, unsigned long x4, unsigned long x5); +void do_info_trace(Monitor *mon); EOF simple_event_num=0
@@ -289,6 +290,7 @@ tracetoh() #define TRACE_H #include "qemu-common.h" +#include "monitor.h" EOF convert h echo "#endif /* TRACE_H */"
Signature · 10 lines
1.6.2.5 -- Prerna Saxena Linux Technology Centre, IBM Systems and Technology Lab, Bangalore, India
RFC PATCH v2 3/3 Toggle tracepoint state
In reply to Prerna SaxenaThis patch adds support for dynamically enabling/disabling of tracepoints. Monitor commands added :
1) info tracepoints : to view all available tracepoints and
their state.
2) tracepoint NAME on|off : to enable/disable data logging from a
given tracepoint.
Eg, tracepoint paio_submit off
disables logging of data when paio_submit is hit.
For now it is a simple comparison, I'm exploring optimizations that can be employed to make this faster.
--- monitor.c | 16 +++++++++++++++- qemu-monitor.hx | 18 ++++++++++++++++++ simpletrace.c | 53 +++++++++++++++++++++++++++++++++++++++++++++++++++++ tracetool | 30 ++++++++++++++++++++++++++---- vl.c | 6 ++++++ 5 files changed, 118 insertions(+), 5 deletions(-)
monitor.c +15 -1
@@ -547,7 +547,14 @@ static void do_commit(Monitor *mon, const QDict *qdict)bdrv_commit (dinfo->bdrv); } } - +#ifdef CONFIG_SIMPLE_TRACE +static void do_change_tracepoint_state (Monitor *mon,const QDict *qdict) +{ +const char *tp_name =qdict_get_str (qdict,"name" ); +bool new_state =qdict_get_bool (qdict,"option" ); +change_tracepoint_state (tp_name, new_state); +} +#endif static void user_monitor_complete (void *opaque,QObject *ret_data) {MonitorCompletionData *data = (MonitorCompletionData *)opaque;
@@ -2791,6 +2798,13 @@ static const mon_cmd_t info_cmds[] = { .help = "show current contents of trace buffer", .mhandler.info = do_info_trace, }, + { + .name = "tracepoints", + .args_type = "", + .params = "", + .help = "show available tracepoints & their state", + .mhandler.info = do_info_all_tracepoints, + },#endif { .name = NULL,
qemu-monitor.hx +18 -0
@@ -117,6 +117,8 @@ show device tree #ifdef CONFIG_SIMPLE_TRACE @item info trace show contents of trace buffer +@item info tracepoints +show available tracepoints and their state #endif @end table ETEXI
@@ -225,6 +227,22 @@ STEXI @item logfile @var{filename} @findex logfile Output logs to @var{filename}. +#ifdef CONFIG_SIMPLE_TRACE +ETEXI + + { + .name = "tracepoint", + .args_type = "name:s,option:b", + .params = "name on|off", + .help = "changes status of a specific tracepoint", + .mhandler.cmd = do_change_tracepoint_state, + }, + +STEXI +@item tracepoint +@findex tracepoint +changes status of a tracepoint +#endif ETEXI {
simpletrace.c +53 -0
72 lines not on this page · raw message
tracetool +26 -4
@@ -123,14 +123,20 @@ linetoc_end_nop() linetoh_begin_simple() { cat <<EOF +#include <stdbool.h> + typedef unsigned int TraceEvent; +void init_tracepoint_table(void); +void init_tracepoint(const char *tname, TraceEvent tevent); void trace1(TraceEvent event, unsigned long x1); void trace2(TraceEvent event, unsigned long x1, unsigned long x2); void trace3(TraceEvent event, unsigned long x1, unsigned long x2, unsigned long x3); void trace4(TraceEvent event, unsigned long x1, unsigned long x2, unsigned long x3, unsigned long x4); void trace5(TraceEvent event, unsigned long x1, unsigned long x2, unsigned long x3, unsigned long x4, unsigned long x5); void do_info_trace(Monitor *mon); +void do_info_all_tracepoints(Monitor *mon); +void change_tracepoint_state(const char *tname, bool tstate); EOF simple_event_num=0
@@ -163,22 +169,38 @@ EOF linetoh_end_simple() { - return + cat <<EOF +#define NR_TRACEPOINTS $simple_event_num +EOF } linetoc_begin_simple() { - return + cat <<EOF +#include "trace.h" + +void init_tracepoint_table(void) { +EOF + simple_event_num=0 + } linetoc_simple() { - return + local name + name=$(get_name "$1") + cat <<EOF +init_tracepoint("$name", $simple_event_num); +EOF + simple_event_num=$((simple_event_num + 1)) } linetoc_end_simple() { - return + cat <<EOF +return; +} +EOF } linetoh_begin_ust()
vl.c +6 -0
@@ -163,6 +163,9 @@ int main(int argc, char **argv)#include "cpus.h" #include "arch_init.h" +#ifdef CONFIG_SIMPLE_TRACE +#include "trace.h" +#endif //#define DEBUG_NET //#define DEBUG_SLIRP
@@ -3604,6 +3607,9 @@ int main(int argc, char **argv, char **envp)if (net_init_clients () <0 ) {exit (1 ); } +#ifdef CONFIG_SIMPLE_TRACE +init_tracepoint_table (); +#endif /* init the bluetooth world */ if (foreach_device_config (DEV_BT , bt_parse))
Signature · 10 lines
1.6.2.5 -- Prerna Saxena Linux Technology Centre, IBM Systems and Technology Lab, Bangalore, India
Quoted 11 lines · Prerna Saxena
This is v2 of monitor commands based on Stefan's trace framework :
( http://lists.gnu.org/archive/html/qemu-devel/2010-05/msg02407.html )This adds the following monitor commands for the 'simple' backend:
- info trace : to view current contents of the trace buffer.
- info tracepoints : to view all available tracepoints and their
state.
- tracepoint NAME on|off: to enable/disable the logging of data from tracepoint 'NAME'.
Quoted 4 lines
Changelog :
- Command 'info trace' is used to view current contents of buffer, in place of 'trace'.
- Cleanups
Do we want this in QMP?
Quoted 13 lines · Markus Armbruster
Quoted 11 lines · Prerna Saxena
This is v2 of monitor commands based on Stefan's trace framework :
( http://lists.gnu.org/archive/html/qemu-devel/2010-05/msg02407.html )This adds the following monitor commands for the 'simple' backend:
- info trace : to view current contents of the trace buffer.
- info tracepoints : to view all available tracepoints and their
state.
- tracepoint NAME on|off: to enable/disable the logging of data from tracepoint 'NAME'.
Quoted 6 lines
Quoted 4 lines
Changelog :
- Command 'info trace' is used to view current contents of buffer, in place of 'trace'.
- CleanupsDo we want this in QMP?
For sure IMO. Maybe not in a hurry to avoid breakages until the whole tracing infrastructure has settled, but long-term to ease scripting etc.
Still, let's not add this as an old-style monitor command, rather convert it to the new style, maybe blocking QMP for now. I'll post the required infrastructure for that blocking along my next device_show series (hopefully the next days).
Jan
Signature · 2 lines
Siemens AG, Corporate Technology, CT T DE IT 1 Corporate Competence Center Embedded Linux
Quoted 19 lines · On Fri, 11 Jun 2010 14:08:56 +0200 Jan Kiszka <[email protected]> wrote:
Quoted 18 lines · Markus Armbruster
Quoted 15 lines · Prerna Saxena
This is v2 of monitor commands based on Stefan's trace framework :
( http://lists.gnu.org/archive/html/qemu-devel/2010-05/msg02407.html )This adds the following monitor commands for the 'simple' backend:
- info trace : to view current contents of the trace buffer.
- info tracepoints : to view all available tracepoints and their
state.
- tracepoint NAME on|off: to enable/disable the logging of data from tracepoint 'NAME'.Changelog :
- Command 'info trace' is used to view current contents of buffer, in place of 'trace'.
- Cleanups
Quoted 4 lines
Quoted 1 line
Do we want this in QMP?
For sure IMO. Maybe not in a hurry to avoid breakages until the whole tracing infrastructure has settled, but long-term to ease scripting etc.
Yeah, that's why I didn't suggest it in my review.
Quoted 4 lines
Still, let's not add this as an old-style monitor command, rather convert it to the new style, maybe blocking QMP for now. I'll post the required infrastructure for that blocking along my next
device_showseries (hopefully the next days).
Agreed.