From: Steven Rostedt <rostedt@goodmis.org>
To: linux-kernel@vger.kernel.org
Cc: Ingo Molnar <mingo@kernel.org>,
Andrew Morton <akpm@linux-foundation.org>,
Tom Zanussi <tom.zanussi@linux.intel.com>
Subject: [for-next][PATCH 30/46] tracing: Add hist trigger support for variable reference aliases
Date: Tue, 20 Mar 2018 22:21:22 -0400 [thread overview]
Message-ID: <20180321022129.056153500@goodmis.org> (raw)
In-Reply-To: 20180321022052.030055576@goodmis.org
[-- Attachment #1: 0030-tracing-Add-hist-trigger-support-for-variable-refere.patch --]
[-- Type: text/plain, Size: 5460 bytes --]
From: Tom Zanussi <tom.zanussi@linux.intel.com>
Add support for alias=$somevar where alias can be used as
onmatch.xxx($alias).
Aliases are a way of creating a new name for an existing variable, for
flexibly in making naming more clear in certain cases. For example in
the below the user perhaps feels that using $new_lat in the synthetic
event invocation is opaque or doesn't fit well stylistically with
previous triggers, so creates an alias of $new_lat named $latency and
uses that in the call instead:
# echo 'hist:keys=next_pid:new_lat=common_timestamp.usecs' >
/sys/kernel/debug/tracing/events/sched/sched_switch/trigger
# echo 'hist:keys=pid:latency=$new_lat:
onmatch(sched.sched_switch).wake2($latency,pid)' >
/sys/kernel/debug/tracing/events/synthetic/wake1/trigger
Link: http://lkml.kernel.org/r/ef20a65d921af3a873a6f1e8c71407c926d5586f.1516069914.git.tom.zanussi@linux.intel.com
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
kernel/trace/trace_events_hist.c | 74 ++++++++++++++++++++++++++++++++++++----
1 file changed, 67 insertions(+), 7 deletions(-)
diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index 98be6ad883eb..32af523501bc 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -228,6 +228,7 @@ enum hist_field_flags {
HIST_FIELD_FL_EXPR = 1 << 13,
HIST_FIELD_FL_VAR_REF = 1 << 14,
HIST_FIELD_FL_CPU = 1 << 15,
+ HIST_FIELD_FL_ALIAS = 1 << 16,
};
struct var_defs {
@@ -1609,7 +1610,8 @@ static const char *hist_field_name(struct hist_field *field,
if (field->field)
field_name = field->field->name;
- else if (field->flags & HIST_FIELD_FL_LOG2)
+ else if (field->flags & HIST_FIELD_FL_LOG2 ||
+ field->flags & HIST_FIELD_FL_ALIAS)
field_name = hist_field_name(field->operands[0], ++level);
else if (field->flags & HIST_FIELD_FL_TIMESTAMP)
field_name = "common_timestamp";
@@ -2080,7 +2082,7 @@ static struct hist_field *create_hist_field(struct hist_trigger_data *hist_data,
hist_field->hist_data = hist_data;
- if (flags & HIST_FIELD_FL_EXPR)
+ if (flags & HIST_FIELD_FL_EXPR || flags & HIST_FIELD_FL_ALIAS)
goto out; /* caller will populate */
if (flags & HIST_FIELD_FL_VAR_REF) {
@@ -2217,10 +2219,18 @@ static int init_var_ref(struct hist_field *ref_field,
}
}
- ref_field->name = kstrdup(var_field->var.name, GFP_KERNEL);
- if (!ref_field->name) {
- err = -ENOMEM;
- goto free;
+ if (var_field->var.name) {
+ ref_field->name = kstrdup(var_field->var.name, GFP_KERNEL);
+ if (!ref_field->name) {
+ err = -ENOMEM;
+ goto free;
+ }
+ } else if (var_field->name) {
+ ref_field->name = kstrdup(var_field->name, GFP_KERNEL);
+ if (!ref_field->name) {
+ err = -ENOMEM;
+ goto free;
+ }
}
ref_field->type = kstrdup(var_field->type, GFP_KERNEL);
@@ -2382,6 +2392,28 @@ parse_field(struct hist_trigger_data *hist_data, struct trace_event_file *file,
return field;
}
+static struct hist_field *create_alias(struct hist_trigger_data *hist_data,
+ struct hist_field *var_ref,
+ char *var_name)
+{
+ struct hist_field *alias = NULL;
+ unsigned long flags = HIST_FIELD_FL_ALIAS | HIST_FIELD_FL_VAR;
+
+ alias = create_hist_field(hist_data, NULL, flags, var_name);
+ if (!alias)
+ return NULL;
+
+ alias->fn = var_ref->fn;
+ alias->operands[0] = var_ref;
+
+ if (init_var_ref(alias, var_ref, var_ref->system, var_ref->event_name)) {
+ destroy_hist_field(alias, 0);
+ return NULL;
+ }
+
+ return alias;
+}
+
static struct hist_field *parse_atom(struct hist_trigger_data *hist_data,
struct trace_event_file *file, char *str,
unsigned long *flags, char *var_name)
@@ -2415,6 +2447,13 @@ static struct hist_field *parse_atom(struct hist_trigger_data *hist_data,
if (hist_field) {
hist_data->var_refs[hist_data->n_var_refs] = hist_field;
hist_field->var_ref_idx = hist_data->n_var_refs++;
+ if (var_name) {
+ hist_field = create_alias(hist_data, hist_field, var_name);
+ if (!hist_field) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ }
return hist_field;
}
} else
@@ -2515,6 +2554,26 @@ static int check_expr_operands(struct hist_field *operand1,
unsigned long operand1_flags = operand1->flags;
unsigned long operand2_flags = operand2->flags;
+ if ((operand1_flags & HIST_FIELD_FL_VAR_REF) ||
+ (operand1_flags & HIST_FIELD_FL_ALIAS)) {
+ struct hist_field *var;
+
+ var = find_var_field(operand1->var.hist_data, operand1->name);
+ if (!var)
+ return -EINVAL;
+ operand1_flags = var->flags;
+ }
+
+ if ((operand2_flags & HIST_FIELD_FL_VAR_REF) ||
+ (operand2_flags & HIST_FIELD_FL_ALIAS)) {
+ struct hist_field *var;
+
+ var = find_var_field(operand2->var.hist_data, operand2->name);
+ if (!var)
+ return -EINVAL;
+ operand2_flags = var->flags;
+ }
+
if ((operand1_flags & HIST_FIELD_FL_TIMESTAMP_USECS) !=
(operand2_flags & HIST_FIELD_FL_TIMESTAMP_USECS))
return -EINVAL;
@@ -4646,7 +4705,8 @@ static void hist_field_print(struct seq_file *m, struct hist_field *hist_field)
else if (hist_field->flags & HIST_FIELD_FL_CPU)
seq_puts(m, "cpu");
else if (field_name) {
- if (hist_field->flags & HIST_FIELD_FL_VAR_REF)
+ if (hist_field->flags & HIST_FIELD_FL_VAR_REF ||
+ hist_field->flags & HIST_FIELD_FL_ALIAS)
seq_putc(m, '$');
seq_printf(m, "%s", field_name);
}
--
2.15.1
next prev parent reply other threads:[~2018-03-21 2:25 UTC|newest]
Thread overview: 47+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-03-21 2:20 [for-next][PATCH 00/46] tracing: Updates for v4.17 Steven Rostedt
2018-03-21 2:20 ` [for-next][PATCH 01/46] tracing: Move hist trigger Documentation to histogram.txt Steven Rostedt
2018-03-21 2:20 ` [for-next][PATCH 02/46] tracing: Add Documentation for log2 modifier Steven Rostedt
2018-03-21 2:20 ` [for-next][PATCH 03/46] tracing: Add support to detect and avoid duplicates Steven Rostedt
2018-03-21 2:20 ` [for-next][PATCH 04/46] tracing: Remove code which merges duplicates Steven Rostedt
2018-03-21 2:20 ` [for-next][PATCH 05/46] ring-buffer: Add interface for setting absolute time stamps Steven Rostedt
2018-03-21 2:20 ` [for-next][PATCH 06/46] ring-buffer: Redefine the unimplemented RINGBUF_TYPE_TIME_STAMP Steven Rostedt
2018-03-21 2:20 ` [for-next][PATCH 07/46] tracing: Add timestamp_mode trace file Steven Rostedt
2018-03-21 2:21 ` [for-next][PATCH 08/46] tracing: Give event triggers access to ring_buffer_event Steven Rostedt
2018-03-21 2:21 ` [for-next][PATCH 09/46] tracing: Add ring buffer event param to hist field functions Steven Rostedt
2018-03-21 2:21 ` [for-next][PATCH 10/46] tracing: Break out hist trigger assignment parsing Steven Rostedt
2018-03-21 2:21 ` [for-next][PATCH 11/46] tracing: Add hist trigger timestamp support Steven Rostedt
2018-03-21 2:21 ` [for-next][PATCH 12/46] tracing: Add per-element variable support to tracing_map Steven Rostedt
2018-03-21 2:21 ` [for-next][PATCH 13/46] tracing: Add hist_data member to hist_field Steven Rostedt
2018-03-21 2:21 ` [for-next][PATCH 14/46] tracing: Add usecs modifier for hist trigger timestamps Steven Rostedt
2018-03-21 2:21 ` [for-next][PATCH 15/46] tracing: Add variable support to hist triggers Steven Rostedt
2018-03-21 2:21 ` [for-next][PATCH 16/46] tracing: Account for variables in named trigger compatibility Steven Rostedt
2018-03-21 2:21 ` [for-next][PATCH 17/46] tracing: Move get_hist_field_flags() Steven Rostedt
2018-03-21 2:21 ` [for-next][PATCH 18/46] tracing: Add simple expression support to hist triggers Steven Rostedt
2018-03-21 2:21 ` [for-next][PATCH 19/46] tracing: Generalize per-element hist trigger data Steven Rostedt
2018-03-21 2:21 ` [for-next][PATCH 20/46] tracing: Pass tracing_map_elt to hist_field accessor functions Steven Rostedt
2018-03-21 2:21 ` [for-next][PATCH 21/46] tracing: Add hist_field type field Steven Rostedt
2018-03-21 2:21 ` [for-next][PATCH 22/46] tracing: Add variable reference handling to hist triggers Steven Rostedt
2018-03-21 2:21 ` [for-next][PATCH 23/46] tracing: Add hist trigger action hook Steven Rostedt
2018-03-21 2:21 ` [for-next][PATCH 24/46] tracing: Add support for synthetic events Steven Rostedt
2018-03-21 2:21 ` [for-next][PATCH 25/46] tracing: Add support for field variables Steven Rostedt
2018-03-21 2:21 ` [for-next][PATCH 26/46] tracing: Add onmatch hist trigger action support Steven Rostedt
2018-03-21 2:21 ` [for-next][PATCH 27/46] tracing: Add onmax " Steven Rostedt
2018-03-21 2:21 ` [for-next][PATCH 28/46] tracing: Allow whitespace to surround hist trigger filter Steven Rostedt
2018-03-21 2:21 ` [for-next][PATCH 29/46] tracing: Add cpu field for hist triggers Steven Rostedt
2018-03-21 2:21 ` Steven Rostedt [this message]
2018-03-21 2:21 ` [for-next][PATCH 31/46] tracing: Add last error error facility " Steven Rostedt
2018-03-21 2:21 ` [for-next][PATCH 32/46] tracing: Add inter-event hist trigger Documentation Steven Rostedt
2018-03-21 2:21 ` [for-next][PATCH 33/46] tracing: Make tracing_set_clock() non-static Steven Rostedt
2018-03-21 2:21 ` [for-next][PATCH 34/46] tracing: Add a clock attribute for hist triggers Steven Rostedt
2018-03-21 2:21 ` [for-next][PATCH 35/46] ring-buffer: Add nesting for adding events within events Steven Rostedt
2018-03-21 2:21 ` [for-next][PATCH 36/46] tracing: Use the ring-buffer nesting to allow synthetic events to be traced Steven Rostedt
2018-03-21 2:21 ` [for-next][PATCH 37/46] tracing: Add inter-event blurb to HIST_TRIGGERS config option Steven Rostedt
2018-03-21 2:21 ` [for-next][PATCH 38/46] selftests: ftrace: Add inter-event hist triggers testcases Steven Rostedt
2018-03-21 2:21 ` [for-next][PATCH 39/46] tracing: Remove BUG_ON() from append_filter_string() Steven Rostedt
2018-03-21 2:21 ` [for-next][PATCH 40/46] tracing: Use trace_seq instead of open code string appending Steven Rostedt
2018-03-21 2:21 ` [for-next][PATCH 41/46] tracing: Remove filter allocator helper Steven Rostedt
2018-03-21 2:21 ` [for-next][PATCH 42/46] tracing: Only add filter list when needed Steven Rostedt
2018-03-21 2:21 ` [for-next][PATCH 43/46] tracing: Embed replace_filter_string() helper function Steven Rostedt
2018-03-21 2:21 ` [for-next][PATCH 44/46] tracing: Combine enum and arrays into single macro in filter code Steven Rostedt
2018-03-21 2:21 ` [for-next][PATCH 45/46] tracing: Clean up and document pred_funcs_##type creation and use Steven Rostedt
2018-03-21 2:21 ` [for-next][PATCH 46/46] tracing: Rewrite filter logic to be simpler and faster Steven Rostedt
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20180321022129.056153500@goodmis.org \
--to=rostedt@goodmis.org \
--cc=akpm@linux-foundation.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@kernel.org \
--cc=tom.zanussi@linux.intel.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).