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Groups > linux.kernel > #1675174
| From | Tom Zanussi <tom.zanussi@linux.intel.com> |
|---|---|
| Newsgroups | linux.kernel |
| Subject | [PATCH 12/32] tracing: Add hist trigger timestamp support |
| Date | 2017-06-27 01:00 +0200 |
| Message-ID | <tWL99-8u4-73@gated-at.bofh.it> (permalink) |
| References | <tWKZs-8nP-19@gated-at.bofh.it> |
| Organization | linux.* mail to news gateway |
Add support for a timestamp event field. This is actually a 'pseudo-'
event field in that it behaves like it's part of the event record, but
is really part of the corresponding ring buffer event.
To make use of the timestamp field, users can specify
"$common_timestamp" as a field name for any histogram. Note that this
doesn't make much sense on its own either as either a key or value,
but needs to be supported even so, since follow-on patches will add
support for making use of this field in time deltas. The '$' is used
as a prefix on the variable name to indicate that it's not an bonafide
event field - so you won't find it in the event description - but
rather it's a synthetic field that can be used like a real field).
Note that the use of this field requires the ring buffer be put into
TIME_EXTEND_ABS mode, which saves the complete timestamp for each
event rather than an offset. This mode will be enabled if and only if
a histogram makes use of the "$common_timestamp" field.
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
---
kernel/trace/trace_events_hist.c | 90 +++++++++++++++++++++++++++++-----------
1 file changed, 66 insertions(+), 24 deletions(-)
diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index dab6ff6..aeae3b4 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -89,6 +89,12 @@ static u64 hist_field_log2(struct hist_field *hist_field, void *event,
return (u64) ilog2(roundup_pow_of_two(val));
}
+static u64 hist_field_timestamp(struct hist_field *hist_field, void *event,
+ struct ring_buffer_event *rbe)
+{
+ return ring_buffer_event_time_stamp(rbe);
+}
+
#define DEFINE_HIST_FIELD_FN(type) \
static u64 hist_field_##type(struct hist_field *hist_field, \
void *event, \
@@ -135,6 +141,7 @@ enum hist_field_flags {
HIST_FIELD_FL_SYSCALL = 128,
HIST_FIELD_FL_STACKTRACE = 256,
HIST_FIELD_FL_LOG2 = 512,
+ HIST_FIELD_FL_TIMESTAMP = 1024,
};
struct hist_trigger_attrs {
@@ -159,6 +166,7 @@ struct hist_trigger_data {
struct trace_event_file *event_file;
struct hist_trigger_attrs *attrs;
struct tracing_map *map;
+ bool enable_timestamps;
};
static const char *hist_field_name(struct hist_field *field,
@@ -173,6 +181,8 @@ static const char *hist_field_name(struct hist_field *field,
field_name = field->field->name;
else if (field->flags & HIST_FIELD_FL_LOG2)
field_name = hist_field_name(field->operands[0], ++level);
+ else if (field->flags & HIST_FIELD_FL_TIMESTAMP)
+ field_name = "$common_timestamp";
if (field_name == NULL)
field_name = "";
@@ -435,6 +445,12 @@ static struct hist_field *create_hist_field(struct ftrace_event_field *field,
goto out;
}
+ if (flags & HIST_FIELD_FL_TIMESTAMP) {
+ hist_field->fn = hist_field_timestamp;
+ hist_field->size = sizeof(u64);
+ goto out;
+ }
+
if (WARN_ON_ONCE(!field))
goto out;
@@ -512,10 +528,15 @@ static int create_val_field(struct hist_trigger_data *hist_data,
}
}
- field = trace_find_event_field(file->event_call, field_name);
- if (!field) {
- ret = -EINVAL;
- goto out;
+ if (strcmp(field_name, "$common_timestamp") == 0) {
+ flags |= HIST_FIELD_FL_TIMESTAMP;
+ hist_data->enable_timestamps = true;
+ } else {
+ field = trace_find_event_field(file->event_call, field_name);
+ if (!field) {
+ ret = -EINVAL;
+ goto out;
+ }
}
hist_data->fields[val_idx] = create_hist_field(field, flags);
@@ -610,16 +631,22 @@ static int create_key_field(struct hist_trigger_data *hist_data,
}
}
- field = trace_find_event_field(file->event_call, field_name);
- if (!field) {
- ret = -EINVAL;
- goto out;
- }
+ if (strcmp(field_name, "$common_timestamp") == 0) {
+ flags |= HIST_FIELD_FL_TIMESTAMP;
+ hist_data->enable_timestamps = true;
+ key_size = sizeof(u64);
+ } else {
+ field = trace_find_event_field(file->event_call, field_name);
+ if (!field) {
+ ret = -EINVAL;
+ goto out;
+ }
- if (is_string_field(field))
- key_size = MAX_FILTER_STR_VAL;
- else
- key_size = field->size;
+ if (is_string_field(field))
+ key_size = MAX_FILTER_STR_VAL;
+ else
+ key_size = field->size;
+ }
}
hist_data->fields[key_idx] = create_hist_field(field, flags);
@@ -756,7 +783,7 @@ static int create_sort_keys(struct hist_trigger_data *hist_data)
break;
}
- if (strcmp(field_name, "hitcount") == 0) {
+ if ((strcmp(field_name, "hitcount") == 0)) {
descending = is_descending(field_str);
if (descending < 0) {
ret = descending;
@@ -816,6 +843,9 @@ static int create_tracing_map_fields(struct hist_trigger_data *hist_data)
if (hist_field->flags & HIST_FIELD_FL_STACKTRACE)
cmp_fn = tracing_map_cmp_none;
+ else if (!field)
+ cmp_fn = tracing_map_cmp_num(hist_field->size,
+ hist_field->is_signed);
else if (is_string_field(field))
cmp_fn = tracing_map_cmp_string;
else
@@ -1213,7 +1243,11 @@ static void hist_field_print(struct seq_file *m, struct hist_field *hist_field)
{
const char *field_name = hist_field_name(hist_field, 0);
- seq_printf(m, "%s", field_name);
+ if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP)
+ seq_puts(m, "$common_timestamp");
+ else if (field_name)
+ seq_printf(m, "%s", field_name);
+
if (hist_field->flags) {
const char *flags_str = get_hist_field_flags(hist_field);
@@ -1264,27 +1298,25 @@ static int event_hist_trigger_print(struct seq_file *m,
for (i = 0; i < hist_data->n_sort_keys; i++) {
struct tracing_map_sort_key *sort_key;
+ unsigned int idx;
sort_key = &hist_data->sort_keys[i];
+ idx = sort_key->field_idx;
+
+ if (WARN_ON(idx >= TRACING_MAP_FIELDS_MAX))
+ return -EINVAL;
if (i > 0)
seq_puts(m, ",");
- if (sort_key->field_idx == HITCOUNT_IDX)
+ if (idx == HITCOUNT_IDX)
seq_puts(m, "hitcount");
- else {
- unsigned int idx = sort_key->field_idx;
-
- if (WARN_ON(idx >= TRACING_MAP_FIELDS_MAX))
- return -EINVAL;
-
+ else
hist_field_print(m, hist_data->fields[idx]);
- }
if (sort_key->descending)
seq_puts(m, ".descending");
}
-
seq_printf(m, ":size=%u", (1 << hist_data->map->map_bits));
if (data->filter_str)
@@ -1452,6 +1484,10 @@ static bool hist_trigger_match(struct event_trigger_data *data,
return false;
if (key_field->offset != key_field_test->offset)
return false;
+ if (key_field->size != key_field_test->size)
+ return false;
+ if (key_field->is_signed != key_field_test->is_signed)
+ return false;
}
for (i = 0; i < hist_data->n_sort_keys; i++) {
@@ -1534,6 +1570,9 @@ static int hist_register_trigger(char *glob, struct event_trigger_ops *ops,
update_cond_flag(file);
+ if (hist_data->enable_timestamps)
+ tracing_set_time_stamp_abs(file->tr, true);
+
if (trace_event_trigger_enable_disable(file, 1) < 0) {
list_del_rcu(&data->list);
update_cond_flag(file);
@@ -1568,6 +1607,9 @@ static void hist_unregister_trigger(char *glob, struct event_trigger_ops *ops,
if (unregistered && test->ops->free)
test->ops->free(test->ops, test);
+
+ if (hist_data->enable_timestamps)
+ tracing_set_time_stamp_abs(file->tr, false);
}
static void hist_unreg_all(struct trace_event_file *file)
--
1.9.3
Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread
[PATCH 00/32] tracing: Inter-event (e.g. latency) support Tom Zanussi <tom.zanussi@linux.intel.com> - 2017-06-27 00:50 +0200
[PATCH 17/32] tracing: Account for variables in named trigger compatibility Tom Zanussi <tom.zanussi@linux.intel.com> - 2017-06-27 01:00 +0200
[PATCH 02/32] tracing: Reimplement log2 Tom Zanussi <tom.zanussi@linux.intel.com> - 2017-06-27 01:00 +0200
[PATCH 10/32] tracing: Add NO_DISCARD event file flag Tom Zanussi <tom.zanussi@linux.intel.com> - 2017-06-27 01:00 +0200
[PATCH 11/32] tracing: Add post-trigger flag to hist trigger command Tom Zanussi <tom.zanussi@linux.intel.com> - 2017-06-27 01:00 +0200
[PATCH 19/32] tracing: Add variable reference handling to hist triggers Tom Zanussi <tom.zanussi@linux.intel.com> - 2017-06-27 01:00 +0200
[PATCH 29/32] tracing: Add 'last error' error facility for hist triggers Tom Zanussi <tom.zanussi@linux.intel.com> - 2017-06-27 01:00 +0200
[PATCH 04/32] ring-buffer: Redefine the unimplemented RINGBUF_TIME_TIME_STAMP Tom Zanussi <tom.zanussi@linux.intel.com> - 2017-06-27 01:00 +0200
Re: [PATCH 04/32] ring-buffer: Redefine the unimplemented RINGBUF_TIME_TIME_STAMP "Joel Fernandes (Google)" <joel.opensrc@gmail.com> - 2017-07-02 11:00 +0200
[PATCH 06/32] tracing: Add ring buffer event param to hist field functions Tom Zanussi <tom.zanussi@linux.intel.com> - 2017-06-27 01:00 +0200
[PATCH 16/32] tracing: Add variable support to hist triggers Tom Zanussi <tom.zanussi@linux.intel.com> - 2017-06-27 01:00 +0200
[PATCH 20/32] tracing: Add support for dynamic tracepoints Tom Zanussi <tom.zanussi@linux.intel.com> - 2017-06-27 01:00 +0200
[PATCH 24/32] tracing: Add 'onmax' hist trigger action support Tom Zanussi <tom.zanussi@linux.intel.com> - 2017-06-27 01:00 +0200
[PATCH 03/32] ring-buffer: Add interface for setting absolute time stamps Tom Zanussi <tom.zanussi@linux.intel.com> - 2017-06-27 01:00 +0200
[PATCH 13/32] tracing: Add per-element variable support to tracing_map Tom Zanussi <tom.zanussi@linux.intel.com> - 2017-06-27 01:00 +0200
[PATCH 09/32] tracing: Make traceprobe parsing code reusable Tom Zanussi <tom.zanussi@linux.intel.com> - 2017-06-27 01:00 +0200
[PATCH 28/32] tracing: Add hist trigger support for variable reference aliases Tom Zanussi <tom.zanussi@linux.intel.com> - 2017-06-27 01:00 +0200
[PATCH 32/32] tracing: Add a clock attribute for hist triggers Tom Zanussi <tom.zanussi@linux.intel.com> - 2017-06-27 01:00 +0200
[PATCH 25/32] tracing: Allow whitespace to surround hist trigger filter Tom Zanussi <tom.zanussi@linux.intel.com> - 2017-06-27 01:00 +0200
[PATCH 05/32] tracing: Give event triggers access to ring_buffer_event Tom Zanussi <tom.zanussi@linux.intel.com> - 2017-06-27 01:00 +0200
[PATCH 21/32] tracing: Add hist trigger action hook Tom Zanussi <tom.zanussi@linux.intel.com> - 2017-06-27 01:00 +0200
[PATCH 07/32] tracing: Increase tracing map KEYS_MAX size Tom Zanussi <tom.zanussi@linux.intel.com> - 2017-06-27 01:00 +0200
[PATCH 30/32] tracing: Add inter-event hist trigger Documentation Tom Zanussi <tom.zanussi@linux.intel.com> - 2017-06-27 01:00 +0200
[PATCH 31/32] tracing: Make tracing_set_clock() non-static Tom Zanussi <tom.zanussi@linux.intel.com> - 2017-06-27 01:00 +0200
[PATCH 22/32] tracing: Add support for 'synthetic' events Tom Zanussi <tom.zanussi@linux.intel.com> - 2017-06-27 01:00 +0200
[PATCH 12/32] tracing: Add hist trigger timestamp support Tom Zanussi <tom.zanussi@linux.intel.com> - 2017-06-27 01:00 +0200
[PATCH 18/32] tracing: Add simple expression support to hist triggers Tom Zanussi <tom.zanussi@linux.intel.com> - 2017-06-27 01:00 +0200
[PATCH 08/32] tracing: Break out hist trigger assignment parsing Tom Zanussi <tom.zanussi@linux.intel.com> - 2017-06-27 01:00 +0200
[PATCH 15/32] tracing: Add usecs modifier for hist trigger timestamps Tom Zanussi <tom.zanussi@linux.intel.com> - 2017-06-27 01:00 +0200
[PATCH 23/32] tracing: Add 'onmatch' hist trigger action support Tom Zanussi <tom.zanussi@linux.intel.com> - 2017-06-27 01:00 +0200
[PATCH 14/32] tracing: Add hist_data member to hist_field Tom Zanussi <tom.zanussi@linux.intel.com> - 2017-06-27 01:00 +0200
[PATCH 26/32] tracing: Make duplicate count from tracing_map available Tom Zanussi <tom.zanussi@linux.intel.com> - 2017-06-27 01:00 +0200
[PATCH 01/32] tracing: Add hist_field_name() accessor Tom Zanussi <tom.zanussi@linux.intel.com> - 2017-06-27 01:00 +0200
[PATCH 27/32] tracing: Add cpu field for hist triggers Tom Zanussi <tom.zanussi@linux.intel.com> - 2017-06-27 01:00 +0200
Re: [PATCH 00/32] tracing: Inter-event (e.g. latency) support Steven Rostedt <rostedt@goodmis.org> - 2017-06-27 17:10 +0200
Re: [PATCH 00/32] tracing: Inter-event (e.g. latency) support Masami Hiramatsu <mhiramat@kernel.org> - 2017-06-28 16:30 +0200
Re: [PATCH 00/32] tracing: Inter-event (e.g. latency) support Tom Zanussi <tom.zanussi@linux.intel.com> - 2017-06-28 21:20 +0200
Re: [PATCH 00/32] tracing: Inter-event (e.g. latency) support "Joel Fernandes (Google)" <joel.opensrc@gmail.com> - 2017-07-01 09:10 +0200
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