Re: [PATCH v3 6/9] perf tools: add destructors for parse event terms

From: Ian Rogers
Date: Fri Oct 25 2019 - 12:08:52 EST


On Fri, Oct 25, 2019 at 1:27 AM Jiri Olsa <jolsa@xxxxxxxxxx> wrote:
>
> On Thu, Oct 24, 2019 at 12:01:59PM -0700, Ian Rogers wrote:
> > If parsing fails then destructors are ran to clean the up the stack.
> > Rename the head union member to make the term and evlist use cases more
> > distinct, this simplifies matching the correct destructor.
>
> nice did not know about this.. looks like it's been in bison for some time, right?

Looks like it wasn't in Bison 1 but in Bison 2, we're at Bison 3 and
Bison 2 is > 14 years old:
https://web.archive.org/web/20050924004158/http://www.gnu.org/software/bison/manual/html_mono/bison.html#Destructor-Decl

> >
> > Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
> > ---
> > tools/perf/util/parse-events.y | 69 +++++++++++++++++++++++-----------
> > 1 file changed, 48 insertions(+), 21 deletions(-)
> >
> > diff --git a/tools/perf/util/parse-events.y b/tools/perf/util/parse-events.y
> > index 545ab7cefc20..4725b14b9db4 100644
> > --- a/tools/perf/util/parse-events.y
> > +++ b/tools/perf/util/parse-events.y
> > @@ -12,6 +12,7 @@
> > #include <stdio.h>
> > #include <linux/compiler.h>
> > #include <linux/types.h>
> > +#include <linux/zalloc.h>
> > #include "pmu.h"
> > #include "evsel.h"
> > #include "parse-events.h"
> > @@ -37,6 +38,25 @@ static struct list_head* alloc_list()
> > return list;
> > }
> >
> > +static void free_list_evsel(struct list_head* list_evsel)
> > +{
> > + struct perf_evsel *pos, *tmp;
> > +
> > + list_for_each_entry_safe(pos, tmp, list_evsel, node) {
> > + list_del_init(&pos->node);
> > + perf_evsel__delete(pos);
> > + }
> > + free(list_evsel);
>
> I think you need to iterate 'struct evsel' in here, not 'struct perf_evsel'
>
> should be:
>
> struct evsel *evsel, *tmp;
>
> list_for_each_entry_safe(evsel, tmp, list_evsel, core.node) {
> list_del_init(&evsel->core.node);
> evsel__delete(evsel);
> }

Thanks, I'll address this.

Ian

> thanks,
> jirka
>
> > +}
> > +
> > +static void free_term(struct parse_events_term *term)
> > +{
> > + if (term->type_val == PARSE_EVENTS__TERM_TYPE_STR)
> > + free(term->val.str);
> > + zfree(&term->array.ranges);
> > + free(term);
> > +}
> > +
> > static void inc_group_count(struct list_head *list,
> > struct parse_events_state *parse_state)
> > {
> > @@ -66,6 +86,7 @@ static void inc_group_count(struct list_head *list,
> > %type <num> PE_VALUE_SYM_TOOL
> > %type <num> PE_RAW
> > %type <num> PE_TERM
> > +%type <num> value_sym
> > %type <str> PE_NAME
> > %type <str> PE_BPF_OBJECT
> > %type <str> PE_BPF_SOURCE
> > @@ -76,37 +97,43 @@ static void inc_group_count(struct list_head *list,
> > %type <str> PE_EVENT_NAME
> > %type <str> PE_PMU_EVENT_PRE PE_PMU_EVENT_SUF PE_KERNEL_PMU_EVENT
> > %type <str> PE_DRV_CFG_TERM
> > -%type <num> value_sym
> > -%type <head> event_config
> > -%type <head> opt_event_config
> > -%type <head> opt_pmu_config
> > +%destructor { free ($$); } <str>
> > %type <term> event_term
> > -%type <head> event_pmu
> > -%type <head> event_legacy_symbol
> > -%type <head> event_legacy_cache
> > -%type <head> event_legacy_mem
> > -%type <head> event_legacy_tracepoint
> > +%destructor { free_term ($$); } <term>
> > +%type <list_terms> event_config
> > +%type <list_terms> opt_event_config
> > +%type <list_terms> opt_pmu_config
> > +%destructor { parse_events_terms__delete ($$); } <list_terms>
> > +%type <list_evsel> event_pmu
> > +%type <list_evsel> event_legacy_symbol
> > +%type <list_evsel> event_legacy_cache
> > +%type <list_evsel> event_legacy_mem
> > +%type <list_evsel> event_legacy_tracepoint
> > +%type <list_evsel> event_legacy_numeric
> > +%type <list_evsel> event_legacy_raw
> > +%type <list_evsel> event_bpf_file
> > +%type <list_evsel> event_def
> > +%type <list_evsel> event_mod
> > +%type <list_evsel> event_name
> > +%type <list_evsel> event
> > +%type <list_evsel> events
> > +%type <list_evsel> group_def
> > +%type <list_evsel> group
> > +%type <list_evsel> groups
> > +%destructor { free_list_evsel ($$); } <list_evsel>
> > %type <tracepoint_name> tracepoint_name
> > -%type <head> event_legacy_numeric
> > -%type <head> event_legacy_raw
> > -%type <head> event_bpf_file
> > -%type <head> event_def
> > -%type <head> event_mod
> > -%type <head> event_name
> > -%type <head> event
> > -%type <head> events
> > -%type <head> group_def
> > -%type <head> group
> > -%type <head> groups
> > +%destructor { free ($$.sys); free ($$.event); } <tracepoint_name>
> > %type <array> array
> > %type <array> array_term
> > %type <array> array_terms
> > +%destructor { free ($$.ranges); } <array>
> >
> > %union
> > {
> > char *str;
> > u64 num;
> > - struct list_head *head;
> > + struct list_head *list_evsel;
> > + struct list_head *list_terms;
> > struct parse_events_term *term;
> > struct tracepoint_name {
> > char *sys;
> > --
> > 2.23.0.866.gb869b98d4c-goog
> >
>