When the event numbers registered by multiple PMUs overlap, the
attr->type value passed to perf_event_create_kernel_counter() is used
to determine which PMU to use to create a perf_event.
However, when the PMU in question is not a standard PMU (defined in
perf_type_id), there is no way for a kernel client to look up the PMU
type for the PMU of interest and set the attr->type appropriately.
So, add an API to look up the PMU type by name. That way, the kernel
APIs can function in a fashion similar to the user space interface.
Signed-off-by: Saravana Kannan <skan...@codeaurora.org>
---
kernel/events/core.c | 23 +++++++++++++++++++++++
1 file changed, 23 insertions(+)
diff --git a/kernel/events/core.c b/kernel/events/core.c
index 96db9ae..5d3df58 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -10310,6 +10310,29 @@ static int perf_event_set_clock(struct perf_event
*event, clockid_t clk_id)
return err;
}
+int perf_find_pmu_type_by_name(const char *name)
+{
+ struct pmu *pmu;
+ int ret = -1;
+
+ mutex_lock(&pmus_lock);
+
+ list_for_each_entry(pmu, &pmus, entry) {
+ if (!pmu->name || pmu->type < 0)
+ continue;
+
+ if (!strcmp(name, pmu->name)) {
+ ret = pmu->type;
+ goto out;
+ }
+ }
+
+out:
+ mutex_unlock(&pmus_lock);
+
+ return ret;
+}
+
/**
* perf_event_create_kernel_counter
*
--
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