11 files changed, 96 insertions, 69 deletions

diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 22dd05d3680c..f5b6137c0f7e 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -185,18 +185,18 @@ static bool perf_evlist__equal(struct perf_evlist *evlist,
 
 static void perf_record__open(struct perf_record *rec)
 {
-        struct perf_evsel *pos, *first;
+        struct perf_evsel *pos;
         struct perf_evlist *evlist = rec->evlist;
         struct perf_session *session = rec->session;
         struct perf_record_opts *opts = &rec->opts;
 
-        first = list_entry(evlist->entries.next, struct perf_evsel, node);
-
         perf_evlist__config_attrs(evlist, opts);
 
+        if (opts->group)
+                perf_evlist__group(evlist);
+
         list_for_each_entry(pos, &evlist->entries, node) {
                 struct perf_event_attr *attr = &pos->attr;
-                struct xyarray *group_fd = NULL;
                 /*
                  * Check if parse_single_tracepoint_event has already asked for
                  * PERF_SAMPLE_TIME.
@@ -211,16 +211,13 @@ static void perf_record__open(struct perf_record *rec)
                  */
                 bool time_needed = attr->sample_type & PERF_SAMPLE_TIME;
 
-                if (opts->group && pos != first)
-                        group_fd = first->fd;
 fallback_missing_features:
                 if (opts->exclude_guest_missing)
                         attr->exclude_guest = attr->exclude_host = 0;
 retry_sample_id:
                 attr->sample_id_all = opts->sample_id_all_missing ? 0 : 1;
 try_again:
-                if (perf_evsel__open(pos, evlist->cpus, evlist->threads,
-                                     opts->group, group_fd) < 0) {
+                if (perf_evsel__open(pos, evlist->cpus, evlist->threads) < 0) {
                         int err = errno;
 
                         if (err == EPERM || err == EACCES) {
diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c
index 861f0aec77ae..23908a85bba9 100644
--- a/tools/perf/builtin-stat.c
+++ b/tools/perf/builtin-stat.c
@@ -281,13 +281,9 @@ static int create_perf_stat_counter(struct perf_evsel *evsel,
                                     struct perf_evsel *first)
 {
         struct perf_event_attr *attr = &evsel->attr;
-        struct xyarray *group_fd = NULL;
         bool exclude_guest_missing = false;
         int ret;
 
-        if (group && evsel != first)
-                group_fd = first->fd;
-
         if (scale)
                 attr->read_format = PERF_FORMAT_TOTAL_TIME_ENABLED |
                                     PERF_FORMAT_TOTAL_TIME_RUNNING;
@@ -299,8 +295,7 @@ retry:
                 evsel->attr.exclude_guest = evsel->attr.exclude_host = 0;
 
         if (perf_target__has_cpu(&target)) {
-                ret = perf_evsel__open_per_cpu(evsel, evsel_list->cpus,
-                                               group, group_fd);
+                ret = perf_evsel__open_per_cpu(evsel, evsel_list->cpus);
                 if (ret)
                         goto check_ret;
                 return 0;
@@ -311,8 +306,7 @@ retry:
                 attr->enable_on_exec = 1;
         }
 
-        ret = perf_evsel__open_per_thread(evsel, evsel_list->threads,
-                                          group, group_fd);
+        ret = perf_evsel__open_per_thread(evsel, evsel_list->threads);
         if (!ret)
                 return 0;
         /* fall through */
@@ -483,6 +477,9 @@ static int run_perf_stat(int argc __used, const char **argv)
                 close(child_ready_pipe[0]);
         }
 
+        if (group)
+                perf_evlist__group(evsel_list);
+
         first = list_entry(evsel_list->entries.next, struct perf_evsel, node);
 
         list_for_each_entry(counter, &evsel_list->entries, node) {
diff --git a/tools/perf/builtin-test.c b/tools/perf/builtin-test.c
index 1d592f5cbea9..9a479b68fc9b 100644
--- a/tools/perf/builtin-test.c
+++ b/tools/perf/builtin-test.c
@@ -294,7 +294,7 @@ static int test__open_syscall_event(void)
                 goto out_thread_map_delete;
         }
 
-        if (perf_evsel__open_per_thread(evsel, threads, false, NULL) < 0) {
+        if (perf_evsel__open_per_thread(evsel, threads) < 0) {
                 pr_debug("failed to open counter: %s, "
                          "tweak /proc/sys/kernel/perf_event_paranoid?\n",
                          strerror(errno));
@@ -369,7 +369,7 @@ static int test__open_syscall_event_on_all_cpus(void)
                 goto out_thread_map_delete;
         }
 
-        if (perf_evsel__open(evsel, cpus, threads, false, NULL) < 0) {
+        if (perf_evsel__open(evsel, cpus, threads) < 0) {
                 pr_debug("failed to open counter: %s, "
                          "tweak /proc/sys/kernel/perf_event_paranoid?\n",
                          strerror(errno));
@@ -533,7 +533,7 @@ static int test__basic_mmap(void)
 
                 perf_evlist__add(evlist, evsels[i]);
 
-                if (perf_evsel__open(evsels[i], cpus, threads, false, NULL) < 0) {
+                if (perf_evsel__open(evsels[i], cpus, threads) < 0) {
                         pr_debug("failed to open counter: %s, "
                                  "tweak /proc/sys/kernel/perf_event_paranoid?\n",
                                  strerror(errno));
@@ -737,7 +737,7 @@ static int test__PERF_RECORD(void)
          * Call sys_perf_event_open on all the fds on all the evsels,
          * grouping them if asked to.
          */
-        err = perf_evlist__open(evlist, opts.group);
+        err = perf_evlist__open(evlist);
         if (err < 0) {
                 pr_debug("perf_evlist__open: %s\n", strerror(errno));
                 goto out_delete_evlist;
diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c
index e45a1ba61722..392d2192b75e 100644
--- a/tools/perf/builtin-top.c
+++ b/tools/perf/builtin-top.c
@@ -886,17 +886,14 @@ static void perf_top__mmap_read(struct perf_top *top)
 
 static void perf_top__start_counters(struct perf_top *top)
 {
-        struct perf_evsel *counter, *first;
+        struct perf_evsel *counter;
         struct perf_evlist *evlist = top->evlist;
 
-        first = list_entry(evlist->entries.next, struct perf_evsel, node);
+        if (top->group)
+                perf_evlist__group(evlist);
 
         list_for_each_entry(counter, &evlist->entries, node) {
                 struct perf_event_attr *attr = &counter->attr;
-                struct xyarray *group_fd = NULL;
-
-                if (top->group && counter != first)
-                        group_fd = first->fd;
 
                 attr->sample_type = PERF_SAMPLE_IP | PERF_SAMPLE_TID;
 
@@ -927,8 +924,7 @@ retry_sample_id:
                 attr->sample_id_all = top->sample_id_all_missing ? 0 : 1;
 try_again:
                 if (perf_evsel__open(counter, top->evlist->cpus,
-                                     top->evlist->threads, top->group,
-                                     group_fd) < 0) {
+                                     top->evlist->threads) < 0) {
                         int err = errno;
 
                         if (err == EPERM || err == EACCES) {
diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c
index 9b38681add9e..feffee3f2bd8 100644
--- a/tools/perf/util/evlist.c
+++ b/tools/perf/util/evlist.c
@@ -108,6 +108,12 @@ void perf_evlist__splice_list_tail(struct perf_evlist *evlist,
         evlist->nr_entries += nr_entries;
 }
 
+void perf_evlist__group(struct perf_evlist *evlist)
+{
+        if (evlist->nr_entries)
+                parse_events__set_leader(&evlist->entries);
+}
+
 int perf_evlist__add_default(struct perf_evlist *evlist)
 {
         struct perf_event_attr attr = {
@@ -757,21 +763,13 @@ void perf_evlist__set_selected(struct perf_evlist *evlist,
         evlist->selected = evsel;
 }
 
-int perf_evlist__open(struct perf_evlist *evlist, bool group)
+int perf_evlist__open(struct perf_evlist *evlist)
 {
-        struct perf_evsel *evsel, *first;
+        struct perf_evsel *evsel;
         int err, ncpus, nthreads;
 
-        first = list_entry(evlist->entries.next, struct perf_evsel, node);
-
         list_for_each_entry(evsel, &evlist->entries, node) {
-                struct xyarray *group_fd = NULL;
-
-                if (group && evsel != first)
-                        group_fd = first->fd;
-
-                err = perf_evsel__open(evsel, evlist->cpus, evlist->threads,
-                                       group, group_fd);
+                err = perf_evsel__open(evsel, evlist->cpus, evlist->threads);
                 if (err < 0)
                         goto out_err;
         }
diff --git a/tools/perf/util/evlist.h b/tools/perf/util/evlist.h
index 528c1acd9298..a19ccd7b51fa 100644
--- a/tools/perf/util/evlist.h
+++ b/tools/perf/util/evlist.h
@@ -85,7 +85,7 @@ struct perf_evsel *perf_evlist__id2evsel(struct perf_evlist *evlist, u64 id);
 
 union perf_event *perf_evlist__mmap_read(struct perf_evlist *self, int idx);
 
-int perf_evlist__open(struct perf_evlist *evlist, bool group);
+int perf_evlist__open(struct perf_evlist *evlist);
 
 void perf_evlist__config_attrs(struct perf_evlist *evlist,
                                struct perf_record_opts *opts);
@@ -132,4 +132,5 @@ void perf_evlist__splice_list_tail(struct perf_evlist *evlist,
                                    struct list_head *list,
                                    int nr_entries);
 
+void perf_evlist__group(struct perf_evlist *evlist);
 #endif /* __PERF_EVLIST_H */
diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index 9c54e8fc2dfc..f5b68e73d751 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -21,7 +21,6 @@
 #include "perf_regs.h"
 
 #define FD(e, x, y) (*(int *)xyarray__entry(e->fd, x, y))
-#define GROUP_FD(group_fd, cpu) (*(int *)xyarray__entry(group_fd, cpu, 0))
 
 static int __perf_evsel__sample_size(u64 sample_type)
 {
@@ -493,6 +492,7 @@ void perf_evsel__delete(struct perf_evsel *evsel)
 {
         perf_evsel__exit(evsel);
         close_cgroup(evsel->cgrp);
+        free(evsel->group_name);
         free(evsel->name);
         free(evsel);
 }
@@ -568,9 +568,28 @@ int __perf_evsel__read(struct perf_evsel *evsel,
         return 0;
 }
 
+static int get_group_fd(struct perf_evsel *evsel, int cpu, int thread)
+{
+        struct perf_evsel *leader = evsel->leader;
+        int fd;
+
+        if (!leader)
+                return -1;
+
+        /*
+         * Leader must be already processed/open,
+         * if not it's a bug.
+         */
+        BUG_ON(!leader->fd);
+
+        fd = FD(leader, cpu, thread);
+        BUG_ON(fd == -1);
+
+        return fd;
+}
+
 static int __perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
-                              struct thread_map *threads, bool group,
-                              struct xyarray *group_fds)
+                              struct thread_map *threads)
 {
         int cpu, thread;
         unsigned long flags = 0;
@@ -586,13 +605,15 @@ static int __perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
         }
 
         for (cpu = 0; cpu < cpus->nr; cpu++) {
-                int group_fd = group_fds ? GROUP_FD(group_fds, cpu) : -1;
 
                 for (thread = 0; thread < threads->nr; thread++) {
+                        int group_fd;
 
                         if (!evsel->cgrp)
                                 pid = threads->map[thread];
 
+                        group_fd = get_group_fd(evsel, cpu, thread);
+
                         FD(evsel, cpu, thread) = sys_perf_event_open(&evsel->attr,
                                                                      pid,
                                                                      cpus->map[cpu],
@@ -602,8 +623,9 @@ static int __perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
                                 goto out_close;
                         }
 
-                        if (group && group_fd == -1)
-                                group_fd = FD(evsel, cpu, thread);
+                        pr_debug("event cpu %d, thread %d, fd %d, group %d\n",
+                                 cpu, pid, FD(evsel, cpu, thread),
+                                 group_fd);
                 }
         }
 
@@ -647,8 +669,7 @@ static struct {
 };
 
 int perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
-                     struct thread_map *threads, bool group,
-                     struct xyarray *group_fd)
+                     struct thread_map *threads)
 {
         if (cpus == NULL) {
                 /* Work around old compiler warnings about strict aliasing */
@@ -658,23 +679,19 @@ int perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
         if (threads == NULL)
                 threads = &empty_thread_map.map;
 
-        return __perf_evsel__open(evsel, cpus, threads, group, group_fd);
+        return __perf_evsel__open(evsel, cpus, threads);
 }
 
 int perf_evsel__open_per_cpu(struct perf_evsel *evsel,
-                             struct cpu_map *cpus, bool group,
-                             struct xyarray *group_fd)
+                             struct cpu_map *cpus)
 {
-        return __perf_evsel__open(evsel, cpus, &empty_thread_map.map, group,
-                                  group_fd);
+        return __perf_evsel__open(evsel, cpus, &empty_thread_map.map);
 }
 
 int perf_evsel__open_per_thread(struct perf_evsel *evsel,
-                                struct thread_map *threads, bool group,
-                                struct xyarray *group_fd)
+                                struct thread_map *threads)
 {
-        return __perf_evsel__open(evsel, &empty_cpu_map.map, threads, group,
-                                  group_fd);
+        return __perf_evsel__open(evsel, &empty_cpu_map.map, threads);
 }
 
 static int perf_event__parse_id_sample(const union perf_event *event, u64 type,
diff --git a/tools/perf/util/evsel.h b/tools/perf/util/evsel.h
index 6a258c90e7ce..c411b421c888 100644
--- a/tools/perf/util/evsel.h
+++ b/tools/perf/util/evsel.h
@@ -70,6 +70,8 @@ struct perf_evsel {
         bool                    supported;
         /* parse modifier helper */
         int                     exclude_GH;
+        struct perf_evsel       *leader;
+        char                    *group_name;
 };
 
 struct cpu_map;
@@ -109,14 +111,11 @@ void perf_evsel__free_id(struct perf_evsel *evsel);
 void perf_evsel__close_fd(struct perf_evsel *evsel, int ncpus, int nthreads);
 
 int perf_evsel__open_per_cpu(struct perf_evsel *evsel,
-                             struct cpu_map *cpus, bool group,
-                             struct xyarray *group_fds);
+                             struct cpu_map *cpus);
 int perf_evsel__open_per_thread(struct perf_evsel *evsel,
-                                struct thread_map *threads, bool group,
-                                struct xyarray *group_fds);
+                                struct thread_map *threads);
 int perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
-                     struct thread_map *threads, bool group,
-                     struct xyarray *group_fds);
+                     struct thread_map *threads);
 void perf_evsel__close(struct perf_evsel *evsel, int ncpus, int nthreads);
 
 #define perf_evsel__match(evsel, t, c)          \
diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index 4364575ce6ac..f6453cd414ae 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -611,14 +611,32 @@ int parse_events_add_pmu(struct list_head **list, int *idx,
                          pmu_event_name(head_config));
 }
 
-int parse_events__modifier_group(struct list_head *list __used,
-                                 char *event_mod __used)
+struct perf_evsel *parse_events__set_leader(struct list_head *list)
 {
-        return 0;
+        struct perf_evsel *evsel, *leader;
+
+        leader = list_entry(list->next, struct perf_evsel, node);
+        leader->leader = NULL;
+
+        list_for_each_entry(evsel, list, node)
+                if (evsel != leader)
+                        evsel->leader = leader;
+
+        return leader;
 }
 
-void parse_events__group(char *name __used, struct list_head *list __used)
+int parse_events__modifier_group(struct list_head *list,
+                                 char *event_mod)
 {
+        return parse_events__modifier_event(list, event_mod, true);
+}
+
+void parse_events__group(char *name, struct list_head *list)
+{
+        struct perf_evsel *leader;
+
+        leader = parse_events__set_leader(list);
+        leader->group_name = name ? strdup(name) : NULL;
 }
 
 void parse_events_update_lists(struct list_head *list_event,
diff --git a/tools/perf/util/parse-events.h b/tools/perf/util/parse-events.h
index 75a6800082a1..e1a184c9e358 100644
--- a/tools/perf/util/parse-events.h
+++ b/tools/perf/util/parse-events.h
@@ -92,6 +92,7 @@ int parse_events_add_breakpoint(struct list_head **list, int *idx,
                                 void *ptr, char *type);
 int parse_events_add_pmu(struct list_head **list, int *idx,
                          char *pmu , struct list_head *head_config);
+struct perf_evsel *parse_events__set_leader(struct list_head *list);
 void parse_events__group(char *name, struct list_head *list);
 void parse_events_update_lists(struct list_head *list_event,
                                struct list_head *list_all);
diff --git a/tools/perf/util/python.c b/tools/perf/util/python.c
index 0688bfb6d280..f5bba4b8eb9e 100644
--- a/tools/perf/util/python.c
+++ b/tools/perf/util/python.c
@@ -627,7 +627,7 @@ static PyObject *pyrf_evsel__open(struct pyrf_evsel *pevsel,
          * This will group just the fds for this single evsel, to group
          * multiple events, use evlist.open().
          */
-        if (perf_evsel__open(evsel, cpus, threads, group, NULL) < 0) {
+        if (perf_evsel__open(evsel, cpus, threads) < 0) {
                 PyErr_SetFromErrno(PyExc_OSError);
                 return NULL;
         }
@@ -824,7 +824,10 @@ static PyObject *pyrf_evlist__open(struct pyrf_evlist *pevlist,
         if (!PyArg_ParseTupleAndKeywords(args, kwargs, "|OOii", kwlist, &group))
                 return NULL;
 
-        if (perf_evlist__open(evlist, group) < 0) {
+        if (group)
+                perf_evlist__group(evlist);
+
+        if (perf_evlist__open(evlist) < 0) {
                 PyErr_SetFromErrno(PyExc_OSError);
                 return NULL;
         }