s390/cpum_cf: Export event names in sysfs

Provide PMU event attributes for supported counters and export their symbolic
names to the sysfs "events" directory.

See the /sys/devices/cpum_cf/events/ directory for a list of available counters.
Note that you might require counter set authorizations for the LPAR to use them.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 12 insertions, 0 deletions

diff --git a/arch/s390/kernel/perf_event.c b/arch/s390/kernel/perf_event.c
index 2343c218b8f9..4c1d336ce941 100644
--- a/arch/s390/kernel/perf_event.c
+++ b/arch/s390/kernel/perf_event.c
@@ -16,6 +16,7 @@
 #include <linux/kvm_host.h>
 #include <linux/percpu.h>
 #include <linux/export.h>
+#include <linux/sysfs.h>
 #include <asm/irq.h>
 #include <asm/cpu_mf.h>
 #include <asm/lowcore.h>
@@ -172,3 +173,14 @@ void perf_callchain_kernel(struct perf_callchain_entry *entry,
         __store_trace(entry, head, S390_lowcore.thread_info,
                       S390_lowcore.thread_info + THREAD_SIZE);
 }
+
+/* Perf defintions for PMU event attributes in sysfs */
+ssize_t cpumf_events_sysfs_show(struct device *dev,
+                                struct device_attribute *attr, char *page)
+{
+        struct perf_pmu_events_attr *pmu_attr;
+
+        pmu_attr = container_of(attr, struct perf_pmu_events_attr, attr);
+        return sprintf(page, "event=0x%04llx,name=%s\n",
+                       pmu_attr->id, attr->attr.name);
+}