6.18-stable review patch. If anyone has any objections, please let me know.
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From: Ian Rogers irogers@google.com
[ Upstream commit 800201997a509c298e74696da3586d82b1a2b6f4 ]
Events with an X modifier were reordered within a group, for example slots was made the leader in: ``` $ perf record -e '{cpu/mem-stores/ppu,cpu/slots/uX}' -- sleep 1 ```
Fix by making `dont_regroup` evsels always use their index for sorting. Make the cur_leader, when fixing the groups, be that of `dont_regroup` evsel so that the `dont_regroup` evsel doesn't become a leader.
On a tigerlake this patch corrects this and meets expectations in: ``` $ perf stat -e '{cpu/mem-stores/,cpu/slots/uX}' -a -- sleep 0.1
Performance counter stats for 'system wide':
83,458,652 cpu/mem-stores/ 2,720,854,880 cpu/slots/uX
0.103780587 seconds time elapsed
$ perf stat -e 'slots,slots:X' -a -- sleep 0.1
Performance counter stats for 'system wide':
732,042,247 slots (48.96%) 643,288,155 slots:X (51.04%)
0.102731018 seconds time elapsed ```
Closes: https://lore.kernel.org/lkml/18f20d38-070c-4e17-bc90-cf7102e1e53d@linux.inte... Fixes: 035c17893082 ("perf parse-events: Add 'X' modifier to exclude an event from being regrouped") Signed-off-by: Ian Rogers irogers@google.com Signed-off-by: Namhyung Kim namhyung@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- tools/perf/util/parse-events.c | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-)
diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c index 90a765016f64f..cd9315d3ca117 100644 --- a/tools/perf/util/parse-events.c +++ b/tools/perf/util/parse-events.c @@ -2121,14 +2121,18 @@ static int evlist__cmp(void *_fg_idx, const struct list_head *l, const struct li * event's index is used. An index may be forced for events that * must be in the same group, namely Intel topdown events. */ - if (*force_grouped_idx != -1 && arch_evsel__must_be_in_group(lhs)) { + if (lhs->dont_regroup) { + lhs_sort_idx = lhs_core->idx; + } else if (*force_grouped_idx != -1 && arch_evsel__must_be_in_group(lhs)) { lhs_sort_idx = *force_grouped_idx; } else { bool lhs_has_group = lhs_core->leader != lhs_core || lhs_core->nr_members > 1;
lhs_sort_idx = lhs_has_group ? lhs_core->leader->idx : lhs_core->idx; } - if (*force_grouped_idx != -1 && arch_evsel__must_be_in_group(rhs)) { + if (rhs->dont_regroup) { + rhs_sort_idx = rhs_core->idx; + } else if (*force_grouped_idx != -1 && arch_evsel__must_be_in_group(rhs)) { rhs_sort_idx = *force_grouped_idx; } else { bool rhs_has_group = rhs_core->leader != rhs_core || rhs_core->nr_members > 1; @@ -2226,10 +2230,10 @@ static int parse_events__sort_events_and_fix_groups(struct list_head *list) */ idx = 0; list_for_each_entry(pos, list, core.node) { - const struct evsel *pos_leader = evsel__leader(pos); + struct evsel *pos_leader = evsel__leader(pos); const char *pos_pmu_name = pos->group_pmu_name; const char *cur_leader_pmu_name; - bool pos_force_grouped = force_grouped_idx != -1 && + bool pos_force_grouped = force_grouped_idx != -1 && !pos->dont_regroup && arch_evsel__must_be_in_group(pos);
/* Reset index and nr_members. */ @@ -2243,8 +2247,8 @@ static int parse_events__sort_events_and_fix_groups(struct list_head *list) * groups can't span PMUs. */ if (!cur_leader || pos->dont_regroup) { - cur_leader = pos; - cur_leaders_grp = &pos->core; + cur_leader = pos->dont_regroup ? pos_leader : pos; + cur_leaders_grp = &cur_leader->core; if (pos_force_grouped) force_grouped_leader = pos; }