This is a note to let you know that I've just added the patch titled
tracing: Use var_refs[] for hist trigger reference checking
to the 4.19-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
tracing-use-var_refs-for-hist-trigger-reference-checking.patch
and it can be found in the queue-4.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From e4f6d245031e04bdd12db390298acec0474a1a46 Mon Sep 17 00:00:00 2001
From: Tom Zanussi <tzanussi@xxxxxxxxx>
Date: Wed, 19 Dec 2018 13:09:16 -0600
Subject: tracing: Use var_refs[] for hist trigger reference checking
From: Tom Zanussi <tzanussi@xxxxxxxxx>
commit e4f6d245031e04bdd12db390298acec0474a1a46 upstream.
Since all the variable reference hist_fields are collected into
hist_data->var_refs[] array, there's no need to go through all the
fields looking for them, or in separate arrays like synth_var_refs[],
which will be going away soon anyway.
This also allows us to get rid of some unnecessary code and functions
currently used for the same purpose.
Link: http://lkml.kernel.org/r/1545246556.4239.7.camel@xxxxxxxxx
Acked-by: Namhyung Kim <namhyung@xxxxxxxxxx>
Reviewed-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
Signed-off-by: Tom Zanussi <tom.zanussi@xxxxxxxxxxxxxxx>
Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
Signed-off-by: George Guo <guodongtai@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
kernel/trace/trace_events_hist.c | 68 ++++++---------------------------------
1 file changed, 11 insertions(+), 57 deletions(-)
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -1289,49 +1289,13 @@ check_field_for_var_ref(struct hist_fiel
struct hist_trigger_data *var_data,
unsigned int var_idx)
{
- struct hist_field *found = NULL;
+ WARN_ON(!(hist_field && hist_field->flags & HIST_FIELD_FL_VAR_REF));
- if (hist_field && hist_field->flags & HIST_FIELD_FL_VAR_REF) {
- if (hist_field->var.idx == var_idx &&
- hist_field->var.hist_data == var_data) {
- found = hist_field;
- }
- }
-
- return found;
-}
-
-static struct hist_field *
-check_field_for_var_refs(struct hist_trigger_data *hist_data,
- struct hist_field *hist_field,
- struct hist_trigger_data *var_data,
- unsigned int var_idx,
- unsigned int level)
-{
- struct hist_field *found = NULL;
- unsigned int i;
+ if (hist_field && hist_field->var.idx == var_idx &&
+ hist_field->var.hist_data == var_data)
+ return hist_field;
- if (level > 3)
- return found;
-
- if (!hist_field)
- return found;
-
- found = check_field_for_var_ref(hist_field, var_data, var_idx);
- if (found)
- return found;
-
- for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++) {
- struct hist_field *operand;
-
- operand = hist_field->operands[i];
- found = check_field_for_var_refs(hist_data, operand, var_data,
- var_idx, level + 1);
- if (found)
- return found;
- }
-
- return found;
+ return NULL;
}
/**
@@ -1350,26 +1314,16 @@ static struct hist_field *find_var_ref(s
struct hist_trigger_data *var_data,
unsigned int var_idx)
{
- struct hist_field *hist_field, *found = NULL;
+ struct hist_field *hist_field;
unsigned int i;
- for_each_hist_field(i, hist_data) {
- hist_field = hist_data->fields[i];
- found = check_field_for_var_refs(hist_data, hist_field,
- var_data, var_idx, 0);
- if (found)
- return found;
- }
-
- for (i = 0; i < hist_data->n_synth_var_refs; i++) {
- hist_field = hist_data->synth_var_refs[i];
- found = check_field_for_var_refs(hist_data, hist_field,
- var_data, var_idx, 0);
- if (found)
- return found;
+ for (i = 0; i < hist_data->n_var_refs; i++) {
+ hist_field = hist_data->var_refs[i];
+ if (check_field_for_var_ref(hist_field, var_data, var_idx))
+ return hist_field;
}
- return found;
+ return NULL;
}
/**
Patches currently in stable-queue which might be from tzanussi@xxxxxxxxx are
queue-4.19/tracing-use-var_refs-for-hist-trigger-reference-checking.patch
