Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]
Groups > linux.kernel > #1186102
| From | Tom Zanussi <tom.zanussi@linux.intel.com> |
|---|---|
| Newsgroups | linux.kernel |
| Subject | [PATCH v9 12/22] tracing: Add hist trigger support for pausing and continuing a trace |
| Date | 2015-07-16 19:30 +0200 |
| Message-ID | <pMV8T-4VI-53@gated-at.bofh.it> (permalink) |
| References | <pMV8R-4VI-3@gated-at.bofh.it> |
| Organization | linux.* mail to news gateway |
Allow users to append 'pause' or 'continue' to an existing trigger in
order to have it paused or to have a paused trace continue.
This expands the hist trigger syntax from this:
# echo hist:keys=xxx:vals=yyy:sort=zzz.descending \
[ if filter] > event/trigger
to this:
# echo hist:keys=xxx:vals=yyy:sort=zzz.descending:pause or cont \
[ if filter] > event/trigger
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
---
kernel/trace/trace.c | 5 +++++
kernel/trace/trace_events_hist.c | 26 +++++++++++++++++++++++---
2 files changed, 28 insertions(+), 3 deletions(-)
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 5dd1fc4..547bbc8 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -3791,6 +3791,7 @@ static const char readme_msg[] =
"\t [:values=<field1[,field2,...]]\n"
"\t [:sort=field1,field2,...]\n"
"\t [:size=#entries]\n"
+ "\t [:pause][:continue]\n"
"\t [if <filter>]\n\n"
"\t When a matching event is hit, an entry is added to a hash\n"
"\t table using the key(s) and value(s) named. Keys and values\n"
@@ -3821,6 +3822,10 @@ static const char readme_msg[] =
"\t on. The default if unspecified is 'hitcount' and the.\n"
"\t default sort order is 'ascending'. To sort in the opposite\n"
"\t direction, append .descending' to the sort key.\n\n"
+ "\t The 'pause' param can be used to pause an existing hist\n"
+ "\t trigger or to start a hist trigger but not log any events\n"
+ "\t until told to do so. 'continue' can be used to start or\n"
+ "\t restart a paused hist trigger.\n\n"
#endif
;
diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index 6bf224f..3ae58e7 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -78,6 +78,8 @@ struct hist_trigger_attrs {
char *keys_str;
char *vals_str;
char *sort_key_str;
+ bool pause;
+ bool cont;
unsigned int map_bits;
};
@@ -184,6 +186,11 @@ static struct hist_trigger_attrs *parse_hist_trigger_attrs(char *trigger_str)
attrs->vals_str = kstrdup(str, GFP_KERNEL);
else if (!strncmp(str, "sort", strlen("sort")))
attrs->sort_key_str = kstrdup(str, GFP_KERNEL);
+ else if (!strncmp(str, "pause", strlen("pause")))
+ attrs->pause = true;
+ else if (!strncmp(str, "continue", strlen("continue")) ||
+ !strncmp(str, "cont", strlen("cont")))
+ attrs->cont = true;
else if (!strncmp(str, "size", strlen("size"))) {
int map_bits = parse_map_size(str);
@@ -843,7 +850,10 @@ static int event_hist_trigger_print(struct seq_file *m,
if (data->filter_str)
seq_printf(m, " if %s", data->filter_str);
- seq_puts(m, " [active]");
+ if (data->paused)
+ seq_puts(m, " [paused]");
+ else
+ seq_puts(m, " [active]");
seq_putc(m, '\n');
@@ -882,16 +892,25 @@ static int hist_register_trigger(char *glob, struct event_trigger_ops *ops,
struct event_trigger_data *data,
struct trace_event_file *file)
{
+ struct hist_trigger_data *hist_data = data->private_data;
struct event_trigger_data *test;
int ret = 0;
list_for_each_entry_rcu(test, &file->triggers, list) {
if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
- ret = -EEXIST;
+ if (hist_data->attrs->pause)
+ test->paused = true;
+ else if (hist_data->attrs->cont)
+ test->paused = false;
+ else
+ ret = -EEXIST;
goto out;
}
}
+ if (hist_data->attrs->pause)
+ data->paused = true;
+
if (data->ops->init) {
ret = data->ops->init(data->ops, data);
if (ret < 0)
@@ -984,7 +1003,8 @@ static int event_hist_trigger_func(struct event_command *cmd_ops,
* triggers registered a failure too.
*/
if (!ret) {
- ret = -ENOENT;
+ if (!(attrs->pause || attrs->cont))
+ ret = -ENOENT;
goto out_free;
} else if (ret < 0)
goto out_free;
--
1.9.3
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread
[PATCH v9 00/22] tracing: 'hist' triggers Tom Zanussi <tom.zanussi@linux.intel.com> - 2015-07-16 19:30 +0200
[PATCH v9 09/22] tracing: Add hist trigger support for multiple values ('vals=' param) Tom Zanussi <tom.zanussi@linux.intel.com> - 2015-07-16 19:30 +0200
[PATCH v9 01/22] tracing: Update cond flag when enabling or disabling a trigger Tom Zanussi <tom.zanussi@linux.intel.com> - 2015-07-16 19:30 +0200
[PATCH v9 15/22] tracing: Add hist trigger 'sym' and 'sym-offset' modifiers Tom Zanussi <tom.zanussi@linux.intel.com> - 2015-07-16 19:30 +0200
[PATCH v9 16/22] tracing: Add hist trigger 'execname' modifier Tom Zanussi <tom.zanussi@linux.intel.com> - 2015-07-16 19:30 +0200
[PATCH v9 11/22] tracing: Add hist trigger support for user-defined sorting ('sort=' param) Tom Zanussi <tom.zanussi@linux.intel.com> - 2015-07-16 19:30 +0200
[PATCH v9 12/22] tracing: Add hist trigger support for pausing and continuing a trace Tom Zanussi <tom.zanussi@linux.intel.com> - 2015-07-16 19:30 +0200
Re: [PATCH v9 12/22] tracing: Add hist trigger support for pausing and continuing a trace Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> - 2015-07-22 10:30 +0200
[PATCH v9 08/22] tracing: Add 'hist' event trigger command Tom Zanussi <tom.zanussi@linux.intel.com> - 2015-07-16 19:30 +0200
Re: [PATCH v9 08/22] tracing: Add 'hist' event trigger command Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> - 2015-07-20 15:40 +0200
[PATCH v9 14/22] tracing: Add hist trigger 'hex' modifier for displaying numeric fields Tom Zanussi <tom.zanussi@linux.intel.com> - 2015-07-16 19:30 +0200
[PATCH v9 17/22] tracing: Add hist trigger 'syscall' modifier Tom Zanussi <tom.zanussi@linux.intel.com> - 2015-07-16 19:30 +0200
[PATCH v9 04/22] tracing: Add event record param to trigger_ops.func() Tom Zanussi <tom.zanussi@linux.intel.com> - 2015-07-16 19:30 +0200
[PATCH v9 05/22] tracing: Add get_syscall_name() Tom Zanussi <tom.zanussi@linux.intel.com> - 2015-07-16 19:30 +0200
Re: [PATCH v9 07/22] tracing: Add lock-free tracing_map Peter Zijlstra <peterz@infradead.org> - 2015-07-16 20:00 +0200
Re: [PATCH v9 07/22] tracing: Add lock-free tracing_map Tom Zanussi <tom.zanussi@linux.intel.com> - 2015-07-16 23:50 +0200
Re: [PATCH v9 07/22] tracing: Add lock-free tracing_map Peter Zijlstra <peterz@infradead.org> - 2015-07-17 00:40 +0200
Re: [PATCH v9 07/22] tracing: Add lock-free tracing_map Tom Zanussi <tom.zanussi@linux.intel.com> - 2015-07-17 04:00 +0200
Re: [PATCH v9 07/22] tracing: Add lock-free tracing_map Peter Zijlstra <peterz@infradead.org> - 2015-07-16 20:10 +0200
Re: [PATCH v9 07/22] tracing: Add lock-free tracing_map Tom Zanussi <tom.zanussi@linux.intel.com> - 2015-07-16 23:40 +0200
csiph-web