Re: [PATCH v3 12/27] perf parse-events: Support no alias assigned event inside hybrid PMU
From: Jin, Yao
Date: Thu Apr 15 2021 - 09:36:28 EST
Hi Jiri,
On 4/15/2021 7:03 PM, Jiri Olsa wrote:
On Mon, Mar 29, 2021 at 03:00:31PM +0800, Jin Yao wrote:
SNIP
---
v3:
- Rename the patch:
'perf parse-events: Support hardware events inside PMU' -->
'perf parse-events: Support no alias assigned event inside hybrid PMU'
- Major code is moved to parse-events-hybrid.c.
- Refine the code.
tools/perf/util/parse-events-hybrid.c | 18 +++++-
tools/perf/util/parse-events-hybrid.h | 3 +-
tools/perf/util/parse-events.c | 80 +++++++++++++++++++++++++--
tools/perf/util/parse-events.h | 4 +-
tools/perf/util/parse-events.y | 9 ++-
tools/perf/util/pmu.c | 4 +-
tools/perf/util/pmu.h | 2 +-
7 files changed, 108 insertions(+), 12 deletions(-)
please move the support to pass pmu_name and filter
on it within hybrid code in to separate patch
OK.
diff --git a/tools/perf/util/parse-events-hybrid.c b/tools/perf/util/parse-events-hybrid.c
index 8a630cbab8f3..5bf176b55573 100644
--- a/tools/perf/util/parse-events-hybrid.c
+++ b/tools/perf/util/parse-events-hybrid.c
@@ -64,6 +64,11 @@ static int add_hw_hybrid(struct parse_events_state *parse_state,
int ret;
perf_pmu__for_each_hybrid_pmu(pmu) {
+ if (parse_state->pmu_name &&
+ strcmp(parse_state->pmu_name, pmu->name)) {
+ continue;
please add this check to separate function
if (pmu_cmp(parse_stat))
continue;
OK.
SNIP
+ if (!parse_state->fake_pmu && head_config && !found &&
+ perf_pmu__is_hybrid(name)) {
+ struct parse_events_term *term;
+ int ret;
+
+ list_for_each_entry(term, head_config, list) {
+ if (!term->config)
+ continue;
+
+ ret = parse_events__with_hybrid_pmu(parse_state,
+ term->config,
+ name, &found,
+ list);
+ if (found)
+ return ret;
what if there are more terms in head_config?
should we make sure there's just one term and fail if there's more?
Yes, it should have only one term in head_config.
Now I change the code to:
+ if (!parse_state->fake_pmu && head_config && !found &&
+ perf_pmu__is_hybrid(name)) {
+ struct parse_events_term *term;
+
+ term = list_first_entry(head_config, struct parse_events_term,
+ list);
+ if (term->config) {
+ return parse_events__with_hybrid_pmu(parse_state,
+ term->config,
+ name, list);
+ }
+ }
also we already know the perf_pmu__is_hybrid(name) is true,
so can't we just call:
return parse_events__with_hybrid_pmu(....)
Yes, we can direct return parse_events__with_hybrid_pmu().
+ }
+ }
if (verbose > 1) {
fprintf(stderr, "After aliases, add event pmu '%s' with '",
@@ -1605,6 +1630,15 @@ int parse_events_multi_pmu_add(struct parse_events_state *parse_state,
struct perf_pmu *pmu = NULL;
int ok = 0;
+ if (parse_state->pmu_name) {
+ list = malloc(sizeof(struct list_head));
+ if (!list)
+ return -1;
+ INIT_LIST_HEAD(list);
+ *listp = list;
+ return 0;
+ }
hum, why is this needed?
Hmm, it's not necessary in new code, sorry about that.
+
*listp = NULL;
/* Add it for all PMUs that support the alias */
list = malloc(sizeof(struct list_head));
@@ -2176,6 +2210,44 @@ int parse_events_terms(struct list_head *terms, const char *str)
return ret;
}
+static int list_entries_nr(struct list_head *list)
+{
+ struct list_head *pos;
+ int n = 0;
+
+ list_for_each(pos, list)
+ n++;
+
+ return n;
+}
+
+static int parse_events__with_hybrid_pmu(struct parse_events_state *parse_state,
+ const char *str, char *pmu_name,
+ bool *found, struct list_head *list)
+{
+ struct parse_events_state ps = {
+ .list = LIST_HEAD_INIT(ps.list),
+ .stoken = PE_START_EVENTS,
+ .pmu_name = pmu_name,
+ .idx = parse_state->idx,
+ };
could we add this pmu_name directly to __parse_events?
Do you suggest we directly call __parse_events()?
int __parse_events(struct evlist *evlist, const char *str,
struct parse_events_error *err, struct perf_pmu *fake_pmu)
struct parse_events_state parse_state = {
.list = LIST_HEAD_INIT(parse_state.list),
.idx = evlist->core.nr_entries,
.error = err,
.evlist = evlist,
.stoken = PE_START_EVENTS,
.fake_pmu = fake_pmu,
};
But for parse_events__with_hybrid_pmu, we don't have valid evlist. So if we switch to
__parse_events, evlist processing may be a problem.
So could we still keep current parse_events__with_hybrid_pmu()?
it duplicates the code plus there are some extra checks
you don't do in here and which might be needed, like
last->cmdline_group_boundary setup
+ int ret;
+
+ *found = false;
+ ret = parse_events__scanner(str, &ps);
+ perf_pmu__parse_cleanup();
+
+ if (!ret) {
+ if (!list_empty(&ps.list)) {
+ *found = true;
+ list_splice(&ps.list, list);
+ parse_state->idx = list_entries_nr(list);
could you just use ps.idx instead of list_entries_nr ?
Yes, the code will be changed to:
+
+ if (!ret) {
+ if (!list_empty(&ps.list)) {
+ list_splice(&ps.list, list);
+ parse_state->idx = ps.idx;
+ }
+ }
+ }
+ }
+
+ return ret;
+}
+
int __parse_events(struct evlist *evlist, const char *str,
struct parse_events_error *err, struct perf_pmu *fake_pmu)
{
diff --git a/tools/perf/util/parse-events.h b/tools/perf/util/parse-events.h
index c4f2f96304ce..f9d8e8e41c38 100644
--- a/tools/perf/util/parse-events.h
+++ b/tools/perf/util/parse-events.h
@@ -138,6 +138,7 @@ struct parse_events_state {
struct list_head *terms;
int stoken;
struct perf_pmu *fake_pmu;
+ char *pmu_name;
so it's hybrid specific, we should name it like hybrid_pmu_name or such
OK, I will use hybrid_pmu_name in next version.
Thanks
Jin Yao
thanks,
jirka