Messages in this thread Patch in this message | | | From | Alexander Shishkin <> | Subject | [PATCH v5 16/20] perf: Add a helper for looking up pmus by type | Date | Mon, 13 Oct 2014 16:45:44 +0300 |
| |
This patch adds a helper for looking up a registered pmu by its type.
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> --- kernel/events/core.c | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-)
diff --git a/kernel/events/core.c b/kernel/events/core.c index d4057dff27..92da1aecc7 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -6963,6 +6963,18 @@ void perf_pmu_unregister(struct pmu *pmu) } EXPORT_SYMBOL_GPL(perf_pmu_unregister); +/* call under pmus_srcu */ +static struct pmu *__perf_find_pmu(u32 type) +{ + struct pmu *pmu; + + rcu_read_lock(); + pmu = idr_find(&pmu_idr, type); + rcu_read_unlock(); + + return pmu; +} + struct pmu *perf_init_event(struct perf_event *event) { struct pmu *pmu = NULL; @@ -6971,9 +6983,7 @@ struct pmu *perf_init_event(struct perf_event *event) idx = srcu_read_lock(&pmus_srcu); - rcu_read_lock(); - pmu = idr_find(&pmu_idr, event->attr.type); - rcu_read_unlock(); + pmu = __perf_find_pmu(event->attr.type); if (pmu) { if (!try_module_get(pmu->module)) { pmu = ERR_PTR(-ENODEV); -- 2.1.0
| |