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-rw-r--r--kernel/events/core.c307
1 files changed, 254 insertions, 53 deletions
diff --git a/kernel/events/core.c b/kernel/events/core.c
index 8b6a2774e084..c9fee3640f40 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -1460,8 +1460,21 @@ static enum event_type_t get_event_type(struct perf_event *event)
return event_type;
}
-static struct list_head *
-ctx_group_list(struct perf_event *event, struct perf_event_context *ctx)
+/*
+ * Helper function to initialize group leader event;
+ */
+void init_event_group(struct perf_event *event)
+{
+ RB_CLEAR_NODE(&event->group_node);
+ event->group_index = 0;
+}
+
+/*
+ * Extract pinned or flexible groups from the context
+ * based on event attrs bits;
+ */
+static struct perf_event_groups *
+get_event_groups(struct perf_event *event, struct perf_event_context *ctx)
{
if (event->attr.pinned)
return &ctx->pinned_groups;
@@ -1470,6 +1483,169 @@ ctx_group_list(struct perf_event *event, struct perf_event_context *ctx)
}
/*
+ * Helper function to initializes perf event groups object;
+ */
+void perf_event_groups_init(struct perf_event_groups *groups)
+{
+ groups->tree = RB_ROOT;
+ groups->index = 0;
+}
+
+/*
+ * Compare function for event groups;
+ * Implements complex key that first sorts by CPU and then by
+ * virtual index which provides ordering when rotating
+ * groups for the same CPU;
+ */
+int perf_event_groups_less(struct perf_event *left, struct perf_event *right)
+{
+ if (left->cpu < right->cpu) {
+ return 1;
+ } else if (left->cpu > right->cpu) {
+ return 0;
+ } else {
+ if (left->group_index < right->group_index) {
+ return 1;
+ } else if(left->group_index > right->group_index) {
+ return 0;
+ } else {
+ return 0;
+ }
+ }
+}
+
+/*
+ * Insert a group into a tree using event->cpu as a key. If event->cpu node
+ * is already attached to the tree then the event is added to the attached
+ * group's group_list list.
+ */
+static void
+perf_event_groups_insert(struct perf_event_groups *groups,
+ struct perf_event *event)
+{
+ struct perf_event *node_event;
+ struct rb_node *parent;
+ struct rb_node **node;
+
+ event->group_index = ++groups->index;
+
+ node = &groups->tree.rb_node;
+ parent = *node;
+
+ while (*node) {
+ parent = *node;
+ node_event = container_of(*node,
+ struct perf_event, group_node);
+
+ if (perf_event_groups_less(event, node_event))
+ node = &parent->rb_left;
+ else
+ node = &parent->rb_right;
+ }
+
+ rb_link_node(&event->group_node, parent, node);
+ rb_insert_color(&event->group_node, &groups->tree);
+}
+
+/*
+ * Helper function to insert event into the pinned or
+ * flexible groups;
+ */
+static void
+add_event_to_groups(struct perf_event *event, struct perf_event_context *ctx)
+{
+ struct perf_event_groups *groups;
+
+ groups = get_event_groups(event, ctx);
+ perf_event_groups_insert(groups, event);
+}
+
+/*
+ * Delete a group from a tree. If the group is directly attached to the tree
+ * it also detaches all groups on the group's group_list list.
+ */
+static void
+perf_event_groups_delete(struct perf_event_groups *groups,
+ struct perf_event *event)
+{
+ if (!RB_EMPTY_NODE(&event->group_node) &&
+ !RB_EMPTY_ROOT(&groups->tree))
+ rb_erase(&event->group_node, &groups->tree);
+
+ init_event_group(event);
+}
+
+/*
+ * Helper function to delete event from its groups;
+ */
+static void
+del_event_from_groups(struct perf_event *event, struct perf_event_context *ctx)
+{
+ struct perf_event_groups *groups;
+
+ groups = get_event_groups(event, ctx);
+ perf_event_groups_delete(groups, event);
+}
+
+/*
+ * Get a group by a cpu key from groups tree with the least group_index;
+ */
+static struct perf_event *
+perf_event_groups_first(struct perf_event_groups *groups, int cpu)
+{
+ struct perf_event *node_event = NULL, *match = NULL;
+ struct rb_node *node = groups->tree.rb_node;
+
+ while (node) {
+ node_event = container_of(node,
+ struct perf_event, group_node);
+
+ if (cpu < node_event->cpu) {
+ node = node->rb_left;
+ } else if (cpu > node_event->cpu) {
+ node = node->rb_right;
+ } else {
+ match = node_event;
+ node = node->rb_left;
+ }
+ }
+
+ return match;
+}
+
+/*
+ * Find group list by a cpu key and rotate it.
+ */
+static void
+perf_event_groups_rotate(struct perf_event_groups *groups, int cpu)
+{
+ struct perf_event *event =
+ perf_event_groups_first(groups, cpu);
+
+ if (event) {
+ perf_event_groups_delete(groups, event);
+ perf_event_groups_insert(groups, event);
+ }
+}
+
+/*
+ * Iterate event groups thru the whole tree.
+ */
+#define perf_event_groups_for_each(event, groups, node) \
+ for (event = rb_entry_safe(rb_first(&((groups)->tree)), \
+ typeof(*event), node); event; \
+ event = rb_entry_safe(rb_next(&event->node), \
+ typeof(*event), node))
+/*
+ * Iterate event groups with cpu == key.
+ */
+#define perf_event_groups_for_each_cpu(event, key, groups, node) \
+ for (event = perf_event_groups_first(groups, key); \
+ event && event->cpu == key; \
+ event = rb_entry_safe(rb_next(&event->node), \
+ typeof(*event), node))
+
+/*
* Add a event from the lists for its context.
* Must be called with ctx->mutex and ctx->lock held.
*/
@@ -1489,12 +1665,8 @@ list_add_event(struct perf_event *event, struct perf_event_context *ctx)
* perf_group_detach can, at all times, locate all siblings.
*/
if (event->group_leader == event) {
- struct list_head *list;
-
event->group_caps = event->event_caps;
-
- list = ctx_group_list(event, ctx);
- list_add_tail(&event->group_entry, list);
+ add_event_to_groups(event, ctx);
}
list_update_cgroup_event(event, ctx, true);
@@ -1688,7 +1860,7 @@ list_del_event(struct perf_event *event, struct perf_event_context *ctx)
list_del_rcu(&event->event_entry);
if (event->group_leader == event)
- list_del_init(&event->group_entry);
+ del_event_from_groups(event, ctx);
/*
* If event was in error state, then keep it
@@ -1706,7 +1878,6 @@ list_del_event(struct perf_event *event, struct perf_event_context *ctx)
static void perf_group_detach(struct perf_event *event)
{
struct perf_event *sibling, *tmp;
- struct list_head *list = NULL;
lockdep_assert_held(&event->ctx->lock);
@@ -1727,22 +1898,23 @@ static void perf_group_detach(struct perf_event *event)
goto out;
}
- if (!list_empty(&event->group_entry))
- list = &event->group_entry;
-
/*
* If this was a group event with sibling events then
* upgrade the siblings to singleton events by adding them
* to whatever list we are on.
*/
list_for_each_entry_safe(sibling, tmp, &event->sibling_list, group_entry) {
- if (list)
- list_move_tail(&sibling->group_entry, list);
+
sibling->group_leader = sibling;
/* Inherit group flags from the previous leader */
sibling->group_caps = event->group_caps;
+ if (!RB_EMPTY_NODE(&event->group_node)) {
+ list_del_init(&sibling->group_entry);
+ add_event_to_groups(sibling, event->ctx);
+ }
+
WARN_ON_ONCE(sibling->ctx != event->ctx);
}
@@ -2186,6 +2358,22 @@ static int group_can_go_on(struct perf_event *event,
return can_add_hw;
}
+static int
+flexible_group_sched_in(struct perf_event *event,
+ struct perf_event_context *ctx,
+ struct perf_cpu_context *cpuctx,
+ int *can_add_hw)
+{
+ if (event->state <= PERF_EVENT_STATE_OFF || !event_filter_match(event))
+ return 0;
+
+ if (group_can_go_on(event, cpuctx, *can_add_hw))
+ if (group_sched_in(event, cpuctx, ctx))
+ *can_add_hw = 0;
+
+ return 1;
+}
+
static void add_event_to_ctx(struct perf_event *event,
struct perf_event_context *ctx)
{
@@ -2652,6 +2840,7 @@ static void ctx_sched_out(struct perf_event_context *ctx,
struct perf_cpu_context *cpuctx,
enum event_type_t event_type)
{
+ int sw = -1, cpu = smp_processor_id();
int is_active = ctx->is_active;
struct perf_event *event;
@@ -2700,12 +2889,20 @@ static void ctx_sched_out(struct perf_event_context *ctx,
perf_pmu_disable(ctx->pmu);
if (is_active & EVENT_PINNED) {
- list_for_each_entry(event, &ctx->pinned_groups, group_entry)
+ perf_event_groups_for_each_cpu(event, cpu,
+ &ctx->pinned_groups, group_node)
+ group_sched_out(event, cpuctx, ctx);
+ perf_event_groups_for_each_cpu(event, sw,
+ &ctx->pinned_groups, group_node)
group_sched_out(event, cpuctx, ctx);
}
if (is_active & EVENT_FLEXIBLE) {
- list_for_each_entry(event, &ctx->flexible_groups, group_entry)
+ perf_event_groups_for_each_cpu(event, cpu,
+ &ctx->flexible_groups, group_node)
+ group_sched_out(event, cpuctx, ctx);
+ perf_event_groups_for_each_cpu(event, sw,
+ &ctx->flexible_groups, group_node)
group_sched_out(event, cpuctx, ctx);
}
perf_pmu_enable(ctx->pmu);
@@ -2996,23 +3193,28 @@ static void
ctx_pinned_sched_in(struct perf_event_context *ctx,
struct perf_cpu_context *cpuctx)
{
+ int sw = -1, cpu = smp_processor_id();
struct perf_event *event;
+ int can_add_hw;
+
+ perf_event_groups_for_each_cpu(event, sw,
+ &ctx->pinned_groups, group_node) {
+ can_add_hw = 1;
+ if (flexible_group_sched_in(event, ctx, cpuctx, &can_add_hw)) {
+ if (event->state == PERF_EVENT_STATE_INACTIVE)
+ perf_event_set_state(event,
+ PERF_EVENT_STATE_ERROR);
+ }
+ }
- list_for_each_entry(event, &ctx->pinned_groups, group_entry) {
- if (event->state <= PERF_EVENT_STATE_OFF)
- continue;
- if (!event_filter_match(event))
- continue;
-
- if (group_can_go_on(event, cpuctx, 1))
- group_sched_in(event, cpuctx, ctx);
-
- /*
- * If this pinned group hasn't been scheduled,
- * put it in error state.
- */
- if (event->state == PERF_EVENT_STATE_INACTIVE)
- perf_event_set_state(event, PERF_EVENT_STATE_ERROR);
+ perf_event_groups_for_each_cpu(event, cpu,
+ &ctx->pinned_groups, group_node) {
+ can_add_hw = 1;
+ if (flexible_group_sched_in(event, ctx, cpuctx, &can_add_hw)) {
+ if (event->state == PERF_EVENT_STATE_INACTIVE)
+ perf_event_set_state(event,
+ PERF_EVENT_STATE_ERROR);
+ }
}
}
@@ -3020,25 +3222,19 @@ static void
ctx_flexible_sched_in(struct perf_event_context *ctx,
struct perf_cpu_context *cpuctx)
{
+ int sw = -1, cpu = smp_processor_id();
struct perf_event *event;
int can_add_hw = 1;
- list_for_each_entry(event, &ctx->flexible_groups, group_entry) {
- /* Ignore events in OFF or ERROR state */
- if (event->state <= PERF_EVENT_STATE_OFF)
- continue;
- /*
- * Listen to the 'cpu' scheduling filter constraint
- * of events:
- */
- if (!event_filter_match(event))
- continue;
+ perf_event_groups_for_each_cpu(event, sw,
+ &ctx->flexible_groups, group_node)
+ flexible_group_sched_in(event, ctx, cpuctx, &can_add_hw);
+
+ can_add_hw = 1;
+ perf_event_groups_for_each_cpu(event, cpu,
+ &ctx->flexible_groups, group_node)
+ flexible_group_sched_in(event, ctx, cpuctx, &can_add_hw);
- if (group_can_go_on(event, cpuctx, can_add_hw)) {
- if (group_sched_in(event, cpuctx, ctx))
- can_add_hw = 0;
- }
- }
}
static void
@@ -3119,7 +3315,7 @@ static void perf_event_context_sched_in(struct perf_event_context *ctx,
* However, if task's ctx is not carrying any pinned
* events, no need to flip the cpuctx's events around.
*/
- if (!list_empty(&ctx->pinned_groups))
+ if (!RB_EMPTY_ROOT(&ctx->pinned_groups.tree))
cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE);
perf_event_sched_in(cpuctx, ctx, task);
perf_pmu_enable(ctx->pmu);
@@ -3356,8 +3552,12 @@ static void rotate_ctx(struct perf_event_context *ctx)
* Rotate the first entry last of non-pinned groups. Rotation might be
* disabled by the inheritance code.
*/
- if (!ctx->rotate_disable)
- list_rotate_left(&ctx->flexible_groups);
+ if (!ctx->rotate_disable) {
+ int sw = -1, cpu = smp_processor_id();
+
+ perf_event_groups_rotate(&ctx->flexible_groups, sw);
+ perf_event_groups_rotate(&ctx->flexible_groups, cpu);
+ }
}
static int perf_rotate_context(struct perf_cpu_context *cpuctx)
@@ -3715,8 +3915,8 @@ static void __perf_event_init_context(struct perf_event_context *ctx)
raw_spin_lock_init(&ctx->lock);
mutex_init(&ctx->mutex);
INIT_LIST_HEAD(&ctx->active_ctx_list);
- INIT_LIST_HEAD(&ctx->pinned_groups);
- INIT_LIST_HEAD(&ctx->flexible_groups);
+ perf_event_groups_init(&ctx->pinned_groups);
+ perf_event_groups_init(&ctx->flexible_groups);
INIT_LIST_HEAD(&ctx->event_list);
atomic_set(&ctx->refcount, 1);
}
@@ -9561,6 +9761,7 @@ perf_event_alloc(struct perf_event_attr *attr, int cpu,
INIT_LIST_HEAD(&event->group_entry);
INIT_LIST_HEAD(&event->event_entry);
INIT_LIST_HEAD(&event->sibling_list);
+ init_event_group(event);
INIT_LIST_HEAD(&event->rb_entry);
INIT_LIST_HEAD(&event->active_entry);
INIT_LIST_HEAD(&event->addr_filters.list);
@@ -11085,7 +11286,7 @@ static int perf_event_init_context(struct task_struct *child, int ctxn)
* We dont have to disable NMIs - we are only looking at
* the list, not manipulating it:
*/
- list_for_each_entry(event, &parent_ctx->pinned_groups, group_entry) {
+ perf_event_groups_for_each(event, &parent_ctx->pinned_groups, group_node) {
ret = inherit_task_group(event, parent, parent_ctx,
child, ctxn, &inherited_all);
if (ret)
@@ -11101,7 +11302,7 @@ static int perf_event_init_context(struct task_struct *child, int ctxn)
parent_ctx->rotate_disable = 1;
raw_spin_unlock_irqrestore(&parent_ctx->lock, flags);
- list_for_each_entry(event, &parent_ctx->flexible_groups, group_entry) {
+ perf_event_groups_for_each(event, &parent_ctx->flexible_groups, group_node) {
ret = inherit_task_group(event, parent, parent_ctx,
child, ctxn, &inherited_all);
if (ret)