Messages in this thread Patch in this message | | | From | Borislav Petkov <> | Subject | [PATCH 03/21] perf_events: Add a helper to search for an event in a context | Date | Thu, 1 Jul 2010 17:55:45 +0200 |
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From: Borislav Petkov <borislav.petkov@amd.com>
This is a straignt-forward helper to look for, e.g. already allocated and enabled events (think persistent events here).
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com> --- kernel/perf_event.c | 21 +++++++++++++++++++++ 1 files changed, 21 insertions(+), 0 deletions(-)
diff --git a/kernel/perf_event.c b/kernel/perf_event.c index 40478af..168764b 100644 --- a/kernel/perf_event.c +++ b/kernel/perf_event.c @@ -307,6 +307,27 @@ list_add_event(struct perf_event *event, struct perf_event_context *ctx) ctx->nr_stat++; } +/* + * Find an event in a context. + * Must be called with ctx->mutex and ctx->lock held. + */ +static struct perf_event *find_event_in_context(struct perf_event_attr *attr, + struct perf_event_context *ctx) +{ + struct perf_event *event; + + rcu_read_lock(); + list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { + if (event->attr.config == attr->config) { + rcu_read_unlock(); + return event; + } + } + rcu_read_unlock(); + + return NULL; +} + static void perf_group_attach(struct perf_event *event) { struct perf_event *group_leader = event->group_leader; -- 1.7.1
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