Messages in this thread | | | Date | Tue, 28 Jul 2020 09:35:11 -0300 | From | Arnaldo Carvalho de Melo <> | Subject | Re: [PATCH 15/19] perf metric: Add recursion check when processing nested metrics |
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Em Sun, Jul 19, 2020 at 03:40:26PM -0700, Ian Rogers escreveu: > On Sun, Jul 19, 2020 at 11:14 AM Jiri Olsa <jolsa@kernel.org> wrote: > > > > Keeping the stack of nested metrics via 'struct expr_id' objects > > and checking if we are in recursion via already processed metric. > > > > The stack is implemented as static array within the struct egroup > > with 100 entries, which should be enough nesting depth for any > > metric we have or plan to have at the moment. > > > > Adding test that simulates the recursion and checks we can > > detect it. > > > > Signed-off-by: Jiri Olsa <jolsa@kernel.org> > > Acked-by: Ian Rogers <irogers@google.com>
Thanks, applied.
- Arnaldo
> Thanks, > Ian > > > --- > > tools/perf/tests/parse-metric.c | 34 +++++++++- > > tools/perf/util/expr.c | 2 + > > tools/perf/util/expr.h | 9 ++- > > tools/perf/util/metricgroup.c | 117 +++++++++++++++++++++++++++++--- > > 4 files changed, 149 insertions(+), 13 deletions(-) > > > > diff --git a/tools/perf/tests/parse-metric.c b/tools/perf/tests/parse-metric.c > > index aa4d5a9f09a8..01370ccb9ed9 100644 > > --- a/tools/perf/tests/parse-metric.c > > +++ b/tools/perf/tests/parse-metric.c > > @@ -57,6 +57,18 @@ static struct pmu_event pme_test[] = { > > .metric_expr = "d_ratio(dcache_l2_all_miss, dcache_l2_all)", > > .metric_name = "DCache_L2_Misses", > > }, > > +{ > > + .metric_expr = "ipc + m2", > > + .metric_name = "M1", > > +}, > > +{ > > + .metric_expr = "ipc + m1", > > + .metric_name = "M2", > > +}, > > +{ > > + .metric_expr = "1/m3", > > + .metric_name = "M3", > > +} > > }; > > > > static struct pmu_events_map map = { > > @@ -139,8 +151,8 @@ static int compute_metric(const char *name, struct value *vals, double *ratio) > > err = metricgroup__parse_groups_test(evlist, &map, name, > > false, false, > > &metric_events); > > - > > - TEST_ASSERT_VAL("failed to parse metric", err == 0); > > + if (err) > > + return err; > > > > if (perf_evlist__alloc_stats(evlist, false)) > > return -1; > > @@ -264,11 +276,29 @@ static int test_dcache_l2(void) > > return 0; > > } > > > > +static int test_recursion_fail(void) > > +{ > > + double ratio; > > + struct value vals[] = { > > + { .event = "inst_retired.any", .val = 300 }, > > + { .event = "cpu_clk_unhalted.thread", .val = 200 }, > > + { 0 }, > > + }; > > + > > + TEST_ASSERT_VAL("failed to find recursion", > > + compute_metric("M1", vals, &ratio) == -1); > > + > > + TEST_ASSERT_VAL("failed to find recursion", > > + compute_metric("M3", vals, &ratio) == -1); > > + return 0; > > +} > > + > > int test__parse_metric(struct test *test __maybe_unused, int subtest __maybe_unused) > > { > > TEST_ASSERT_VAL("IPC failed", test_ipc() == 0); > > TEST_ASSERT_VAL("frontend failed", test_frontend() == 0); > > TEST_ASSERT_VAL("cache_miss_cycles failed", test_cache_miss_cycles() == 0); > > TEST_ASSERT_VAL("DCache_L2 failed", test_dcache_l2() == 0); > > + TEST_ASSERT_VAL("recursion fail failed", test_recursion_fail() == 0); > > return 0; > > } > > diff --git a/tools/perf/util/expr.c b/tools/perf/util/expr.c > > index a346ca590513..53482ef53c41 100644 > > --- a/tools/perf/util/expr.c > > +++ b/tools/perf/util/expr.c > > @@ -47,6 +47,8 @@ int expr__add_id(struct expr_parse_ctx *ctx, const char *id) > > if (!data_ptr) > > return -ENOMEM; > > > > + data_ptr->parent = ctx->parent; > > + > > ret = hashmap__set(&ctx->ids, id, data_ptr, > > (const void **)&old_key, (void **)&old_data); > > if (ret) > > diff --git a/tools/perf/util/expr.h b/tools/perf/util/expr.h > > index 9ed208d93418..fc2b5e824a66 100644 > > --- a/tools/perf/util/expr.h > > +++ b/tools/perf/util/expr.h > > @@ -13,8 +13,14 @@ > > > > struct metric_ref; > > > > +struct expr_id { > > + char *id; > > + struct expr_id *parent; > > +}; > > + > > struct expr_parse_ctx { > > - struct hashmap ids; > > + struct hashmap ids; > > + struct expr_id *parent; > > }; > > > > struct expr_id_data { > > @@ -25,6 +31,7 @@ struct expr_id_data { > > const char *metric_expr; > > bool counted; > > } ref; > > + struct expr_id *parent; > > }; > > > > bool is_ref; > > diff --git a/tools/perf/util/metricgroup.c b/tools/perf/util/metricgroup.c > > index 332414d93f7a..2a45ee94fd61 100644 > > --- a/tools/perf/util/metricgroup.c > > +++ b/tools/perf/util/metricgroup.c > > @@ -24,6 +24,7 @@ > > #include <subcmd/parse-options.h> > > #include <api/fs/fs.h> > > #include "util.h" > > +#include <asm/bug.h> > > > > struct metric_event *metricgroup__lookup(struct rblist *metric_events, > > struct evsel *evsel, > > @@ -126,6 +127,28 @@ struct egroup { > > bool has_constraint; > > }; > > > > +#define RECURSION_ID_MAX 100 > > + > > +struct expr_ids { > > + struct expr_id id[RECURSION_ID_MAX]; > > + int cnt; > > +}; > > + > > +static struct expr_id *expr_ids__alloc(struct expr_ids *ids) > > +{ > > + if (ids->cnt >= RECURSION_ID_MAX) > > + return NULL; > > + return &ids->id[ids->cnt++]; > > +} > > + > > +static void expr_ids__exit(struct expr_ids *ids) > > +{ > > + int i; > > + > > + for (i = 0; i < ids->cnt; i++) > > + free(ids->id[i].id); > > +} > > + > > /** > > * Find a group of events in perf_evlist that correpond to those from a parsed > > * metric expression. Note, as find_evsel_group is called in the same order as > > @@ -620,7 +643,9 @@ static int __add_metric(struct list_head *group_list, > > struct pmu_event *pe, > > bool metric_no_group, > > int runtime, > > - struct egroup **egp) > > + struct egroup **egp, > > + struct expr_id *parent, > > + struct expr_ids *ids) > > { > > struct metric_ref_node *ref; > > struct egroup *eg; > > @@ -630,7 +655,7 @@ static int __add_metric(struct list_head *group_list, > > * We got in here for the parent group, > > * allocate it and put it on the list. > > */ > > - eg = malloc(sizeof(*eg)); > > + eg = zalloc(sizeof(*eg)); > > if (!eg) > > return -ENOMEM; > > > > @@ -643,6 +668,18 @@ static int __add_metric(struct list_head *group_list, > > INIT_LIST_HEAD(&eg->metric_refs); > > eg->metric_refs_cnt = 0; > > *egp = eg; > > + > > + parent = expr_ids__alloc(ids); > > + if (!parent) { > > + free(eg); > > + return -EINVAL; > > + } > > + > > + parent->id = strdup(pe->metric_name); > > + if (!parent->id) { > > + free(eg); > > + return -ENOMEM; > > + } > > } else { > > /* > > * We got here for the referenced metric, via the > > @@ -668,6 +705,10 @@ static int __add_metric(struct list_head *group_list, > > eg->metric_refs_cnt++; > > } > > > > + /* Force all found IDs in metric to have us as parent ID. */ > > + WARN_ON_ONCE(!parent); > > + eg->pctx.parent = parent; > > + > > /* > > * For both the parent and referenced metrics, we parse > > * all the metric's IDs and add it to the parent context. > > @@ -728,15 +769,62 @@ static struct pmu_event *find_metric(const char *metric, struct pmu_events_map * > > return NULL; > > } > > > > +static int recursion_check(struct egroup *eg, const char *id, struct expr_id **parent, > > + struct expr_ids *ids) > > +{ > > + struct expr_id_data *data; > > + struct expr_id *p; > > + int ret; > > + > > + /* > > + * We get the parent referenced by 'id' argument and > > + * traverse through all the parent object IDs to check > > + * if we already processed 'id', if we did, it's recursion > > + * and we fail. > > + */ > > + ret = expr__get_id(&eg->pctx, id, &data); > > + if (ret) > > + return ret; > > + > > + p = data->parent; > > + > > + while (p->parent) { > > + if (!strcmp(p->id, id)) { > > + pr_err("failed: recursion detected for %s\n", id); > > + return -1; > > + } > > + p = p->parent; > > + } > > + > > + /* > > + * If we are over the limit of static entris, the metric > > + * is too difficult/nested to process, fail as well. > > + */ > > + p = expr_ids__alloc(ids); > > + if (!p) { > > + pr_err("failed: too many nested metrics\n"); > > + return -EINVAL; > > + } > > + > > + p->id = strdup(id); > > + p->parent = data->parent; > > + *parent = p; > > + > > + return p->id ? 0 : -ENOMEM; > > +} > > + > > static int add_metric(struct list_head *group_list, > > struct pmu_event *pe, > > bool metric_no_group, > > - struct egroup **egp); > > + struct egroup **egp, > > + struct expr_id *parent, > > + struct expr_ids *ids); > > > > static int resolve_metric(struct egroup *eg, > > bool metric_no_group, > > struct list_head *group_list, > > - struct pmu_events_map *map) > > + struct pmu_events_map *map, > > + struct expr_ids *ids) > > { > > struct hashmap_entry *cur; > > size_t bkt; > > @@ -750,18 +838,23 @@ static int resolve_metric(struct egroup *eg, > > do { > > all = true; > > hashmap__for_each_entry((&eg->pctx.ids), cur, bkt) { > > + struct expr_id *parent; > > struct pmu_event *pe; > > > > pe = find_metric(cur->key, map); > > if (!pe) > > continue; > > > > + ret = recursion_check(eg, cur->key, &parent, ids); > > + if (ret) > > + return ret; > > + > > all = false; > > /* The metric key itself needs to go out.. */ > > expr__del_id(&eg->pctx, cur->key); > > > > /* ... and it gets resolved to the parent context. */ > > - ret = add_metric(group_list, pe, metric_no_group, &eg); > > + ret = add_metric(group_list, pe, metric_no_group, &eg, parent, ids); > > if (ret) > > return ret; > > > > @@ -779,14 +872,16 @@ static int resolve_metric(struct egroup *eg, > > static int add_metric(struct list_head *group_list, > > struct pmu_event *pe, > > bool metric_no_group, > > - struct egroup **egp) > > + struct egroup **egp, > > + struct expr_id *parent, > > + struct expr_ids *ids) > > { > > int ret = 0; > > > > pr_debug("metric expr %s for %s\n", pe->metric_expr, pe->metric_name); > > > > if (!strstr(pe->metric_expr, "?")) { > > - ret = __add_metric(group_list, pe, metric_no_group, 1, egp); > > + ret = __add_metric(group_list, pe, metric_no_group, 1, egp, parent, ids); > > } else { > > int j, count; > > > > @@ -798,7 +893,7 @@ static int add_metric(struct list_head *group_list, > > */ > > > > for (j = 0; j < count && !ret; j++) { > > - ret = __add_metric(group_list, pe, metric_no_group, j, egp); > > + ret = __add_metric(group_list, pe, metric_no_group, j, egp, parent, ids); > > } > > } > > > > @@ -811,6 +906,7 @@ static int metricgroup__add_metric(const char *metric, bool metric_no_group, > > struct pmu_events_map *map) > > > > { > > + struct expr_ids ids = { 0 }; > > struct pmu_event *pe; > > struct egroup *eg; > > LIST_HEAD(list); > > @@ -821,7 +917,7 @@ static int metricgroup__add_metric(const char *metric, bool metric_no_group, > > has_match = true; > > eg = NULL; > > > > - ret = add_metric(&list, pe, metric_no_group, &eg); > > + ret = add_metric(&list, pe, metric_no_group, &eg, NULL, &ids); > > if (ret) > > return ret; > > > > @@ -830,7 +926,7 @@ static int metricgroup__add_metric(const char *metric, bool metric_no_group, > > * included in the expression. > > */ > > ret = resolve_metric(eg, metric_no_group, > > - &list, map); > > + &list, map, &ids); > > if (ret) > > return ret; > > } > > @@ -853,6 +949,7 @@ static int metricgroup__add_metric(const char *metric, bool metric_no_group, > > } > > > > list_splice(&list, group_list); > > + expr_ids__exit(&ids); > > return 0; > > } > > > > -- > > 2.25.4 > >
--
- Arnaldo
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