From edb39592a5877bd91b2e6ee15194268f35b04892 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Thu, 15 Mar 2018 17:36:56 +0100 Subject: perf: Fix sibling iteration Mark noticed that the change to sibling_list changed some iteration semantics; because previously we used group_list as list entry, sibling events would always have an empty sibling_list. But because we now use sibling_list for both list head and list entry, siblings will report as having siblings. Fix this with a custom for_each_sibling_event() iterator. Fixes: 8343aae66167 ("perf/core: Remove perf_event::group_entry") Reported-by: Mark Rutland Suggested-by: Mark Rutland Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Thomas Gleixner Cc: vincent.weaver@maine.edu Cc: alexander.shishkin@linux.intel.com Cc: torvalds@linux-foundation.org Cc: alexey.budankov@linux.intel.com Cc: valery.cherepennikov@intel.com Cc: eranian@google.com Cc: acme@redhat.com Cc: linux-tip-commits@vger.kernel.org Cc: davidcc@google.com Cc: kan.liang@intel.com Cc: Dmitry.Prohorov@intel.com Cc: jolsa@redhat.com Link: https://lkml.kernel.org/r/20180315170129.GX4043@hirez.programming.kicks-ass.net --- kernel/events/core.c | 34 ++++++++++++++++------------------ 1 file changed, 16 insertions(+), 18 deletions(-) (limited to 'kernel/events') diff --git a/kernel/events/core.c b/kernel/events/core.c index 3b4c7792a6ac..4d7a460d6669 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -643,7 +643,7 @@ static void perf_event_update_sibling_time(struct perf_event *leader) { struct perf_event *sibling; - list_for_each_entry(sibling, &leader->sibling_list, sibling_list) + for_each_sibling_event(sibling, leader) perf_event_update_time(sibling); } @@ -1828,7 +1828,7 @@ static void perf_group_attach(struct perf_event *event) perf_event__header_size(group_leader); - list_for_each_entry(pos, &group_leader->sibling_list, sibling_list) + for_each_sibling_event(pos, group_leader) perf_event__header_size(pos); } @@ -1928,7 +1928,7 @@ static void perf_group_detach(struct perf_event *event) out: perf_event__header_size(event->group_leader); - list_for_each_entry(tmp, &event->group_leader->sibling_list, sibling_list) + for_each_sibling_event(tmp, event->group_leader) perf_event__header_size(tmp); } @@ -1951,13 +1951,13 @@ static inline int __pmu_filter_match(struct perf_event *event) */ static inline int pmu_filter_match(struct perf_event *event) { - struct perf_event *child; + struct perf_event *sibling; if (!__pmu_filter_match(event)) return 0; - list_for_each_entry(child, &event->sibling_list, sibling_list) { - if (!__pmu_filter_match(child)) + for_each_sibling_event(sibling, event) { + if (!__pmu_filter_match(sibling)) return 0; } @@ -2031,7 +2031,7 @@ group_sched_out(struct perf_event *group_event, /* * Schedule out siblings (if any): */ - list_for_each_entry(event, &group_event->sibling_list, sibling_list) + for_each_sibling_event(event, group_event) event_sched_out(event, cpuctx, ctx); perf_pmu_enable(ctx->pmu); @@ -2310,7 +2310,7 @@ group_sched_in(struct perf_event *group_event, /* * Schedule in siblings as one group (if any): */ - list_for_each_entry(event, &group_event->sibling_list, sibling_list) { + for_each_sibling_event(event, group_event) { if (event_sched_in(event, cpuctx, ctx)) { partial_group = event; goto group_error; @@ -2326,7 +2326,7 @@ group_error: * partial group before returning: * The events up to the failed event are scheduled out normally. */ - list_for_each_entry(event, &group_event->sibling_list, sibling_list) { + for_each_sibling_event(event, group_event) { if (event == partial_group) break; @@ -3863,7 +3863,7 @@ static void __perf_event_read(void *info) pmu->read(event); - list_for_each_entry(sub, &event->sibling_list, sibling_list) { + for_each_sibling_event(sub, event) { if (sub->state == PERF_EVENT_STATE_ACTIVE) { /* * Use sibling's PMU rather than @event's since @@ -4711,7 +4711,7 @@ static int __perf_read_group_add(struct perf_event *leader, if (read_format & PERF_FORMAT_ID) values[n++] = primary_event_id(leader); - list_for_each_entry(sub, &leader->sibling_list, sibling_list) { + for_each_sibling_event(sub, leader) { values[n++] += perf_event_count(sub); if (read_format & PERF_FORMAT_ID) values[n++] = primary_event_id(sub); @@ -4905,7 +4905,7 @@ static void perf_event_for_each(struct perf_event *event, event = event->group_leader; perf_event_for_each_child(event, func); - list_for_each_entry(sibling, &event->sibling_list, sibling_list) + for_each_sibling_event(sibling, event) perf_event_for_each_child(sibling, func); } @@ -6077,7 +6077,7 @@ static void perf_output_read_group(struct perf_output_handle *handle, __output_copy(handle, values, n * sizeof(u64)); - list_for_each_entry(sub, &leader->sibling_list, sibling_list) { + for_each_sibling_event(sub, leader) { n = 0; if ((sub != event) && @@ -10662,8 +10662,7 @@ SYSCALL_DEFINE5(perf_event_open, perf_remove_from_context(group_leader, 0); put_ctx(gctx); - list_for_each_entry(sibling, &group_leader->sibling_list, - sibling_list) { + for_each_sibling_event(sibling, group_leader) { perf_remove_from_context(sibling, 0); put_ctx(gctx); } @@ -10684,8 +10683,7 @@ SYSCALL_DEFINE5(perf_event_open, * By installing siblings first we NO-OP because they're not * reachable through the group lists. */ - list_for_each_entry(sibling, &group_leader->sibling_list, - sibling_list) { + for_each_sibling_event(sibling, group_leader) { perf_event__state_init(sibling); perf_install_in_context(ctx, sibling, sibling->cpu); get_ctx(ctx); @@ -11324,7 +11322,7 @@ static int inherit_group(struct perf_event *parent_event, * case inherit_event() will create individual events, similar to what * perf_group_detach() would do anyway. */ - list_for_each_entry(sub, &parent_event->sibling_list, sibling_list) { + for_each_sibling_event(sub, parent_event) { child_ctr = inherit_event(sub, parent, parent_ctx, child, leader, child_ctx); if (IS_ERR(child_ctr)) -- cgit v1.2.3