perf: Handle stopped state with tracepoints

[pandora-kernel.git] / kernel / perf_event.c

diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index 64a018e..533f715 100644 (file)
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -404,12 +404,17 @@ static inline int perf_cgroup_connect(int fd, struct perf_event *event,
                return -EBADF;
 
        css = cgroup_css_from_dir(file, perf_subsys_id);
-       if (IS_ERR(css))
-               return PTR_ERR(css);
+       if (IS_ERR(css)) {
+               ret = PTR_ERR(css);
+               goto out;
+       }
 
        cgrp = container_of(css, struct perf_cgroup, css);
        event->cgrp = cgrp;
 
+       /* must be done before we fput() the file */
+       perf_get_cgroup(event);
+
        /*
         * all events in a group must monitor
         * the same cgroup because a task belongs
@@ -418,10 +423,8 @@ static inline int perf_cgroup_connect(int fd, struct perf_event *event,
        if (group_leader && group_leader->cgrp != cgrp) {
                perf_detach_cgroup(event);
                ret = -EINVAL;
-       } else {
-               /* must be done before we fput() the file */
-               perf_get_cgroup(event);
        }
+out:
        fput_light(file, fput_needed);
        return ret;
 }
@@ -817,16 +820,8 @@ list_add_event(struct perf_event *event, struct perf_event_context *ctx)
                list_add_tail(&event->group_entry, list);
        }
 
-       if (is_cgroup_event(event)) {
+       if (is_cgroup_event(event))
                ctx->nr_cgroups++;
-               /*
-                * one more event:
-                * - that has cgroup constraint on event->cpu
-                * - that may need work on context switch
-                */
-               atomic_inc(&per_cpu(perf_cgroup_events, event->cpu));
-               jump_label_inc(&perf_sched_events);
-       }
 
        list_add_rcu(&event->event_entry, &ctx->event_list);
        if (!ctx->nr_events)
@@ -954,11 +949,8 @@ list_del_event(struct perf_event *event, struct perf_event_context *ctx)
 
        event->attach_state &= ~PERF_ATTACH_CONTEXT;
 
-       if (is_cgroup_event(event)) {
+       if (is_cgroup_event(event))
                ctx->nr_cgroups--;
-               atomic_dec(&per_cpu(perf_cgroup_events, event->cpu));
-               jump_label_dec(&perf_sched_events);
-       }
 
        ctx->nr_events--;
        if (event->attr.inherit_stat)
@@ -2900,6 +2892,10 @@ static void free_event(struct perf_event *event)
                        atomic_dec(&nr_task_events);
                if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN)
                        put_callchain_buffers();
+               if (is_cgroup_event(event)) {
+                       atomic_dec(&per_cpu(perf_cgroup_events, event->cpu));
+                       jump_label_dec(&perf_sched_events);
+               }
        }
 
        if (event->buffer) {
@@ -5126,7 +5122,7 @@ static int perf_exclude_event(struct perf_event *event,
                              struct pt_regs *regs)
 {
        if (event->hw.state & PERF_HES_STOPPED)
-               return 0;
+               return 1;
 
        if (regs) {
                if (event->attr.exclude_user && user_mode(regs))
@@ -5482,6 +5478,8 @@ static int perf_tp_event_match(struct perf_event *event,
                                struct perf_sample_data *data,
                                struct pt_regs *regs)
 {
+       if (event->hw.state & PERF_HES_STOPPED)
+               return 0;
        /*
         * All tracepoints are from kernel-space.
         */
@@ -6098,17 +6096,22 @@ struct pmu *perf_init_event(struct perf_event *event)
 {
        struct pmu *pmu = NULL;
        int idx;
+       int ret;
 
        idx = srcu_read_lock(&pmus_srcu);
 
        rcu_read_lock();
        pmu = idr_find(&pmu_idr, event->attr.type);
        rcu_read_unlock();
-       if (pmu)
+       if (pmu) {
+               ret = pmu->event_init(event);
+               if (ret)
+                       pmu = ERR_PTR(ret);
                goto unlock;
+       }
 
        list_for_each_entry_rcu(pmu, &pmus, entry) {
-               int ret = pmu->event_init(event);
+               ret = pmu->event_init(event);
                if (!ret)
                        goto unlock;
 
@@ -6470,6 +6473,13 @@ SYSCALL_DEFINE5(perf_event_open,
                err = perf_cgroup_connect(pid, event, &attr, group_leader);
                if (err)
                        goto err_alloc;
+               /*
+                * one more event:
+                * - that has cgroup constraint on event->cpu
+                * - that may need work on context switch
+                */
+               atomic_inc(&per_cpu(perf_cgroup_events, event->cpu));
+               jump_label_inc(&perf_sched_events);
        }
 
        /*
@@ -7338,26 +7348,17 @@ static struct cgroup_subsys_state *perf_cgroup_create(
        struct cgroup_subsys *ss, struct cgroup *cont)
 {
        struct perf_cgroup *jc;
-       struct perf_cgroup_info *t;
-       int c;
 
-       jc = kmalloc(sizeof(*jc), GFP_KERNEL);
+       jc = kzalloc(sizeof(*jc), GFP_KERNEL);
        if (!jc)
                return ERR_PTR(-ENOMEM);
 
-       memset(jc, 0, sizeof(*jc));
-
        jc->info = alloc_percpu(struct perf_cgroup_info);
        if (!jc->info) {
                kfree(jc);
                return ERR_PTR(-ENOMEM);
        }
 
-       for_each_possible_cpu(c) {
-               t = per_cpu_ptr(jc->info, c);
-               t->time = 0;
-               t->timestamp = 0;
-       }
        return &jc->css;
 }