s390/pai: Deny all events not handled by this PMU

Each PAI PMU device driver returns -EINVAL when an event is out of
its accepted range. This return value aborts the search for an
alternative PMU device driver to handle this event.
Change the return value to -ENOENT. This return value is used to
try other PMUs instead.  This makes the PMUs more robust when
the sequence of PMU device driver initialization changes (at boot time)
or by using modules.

Fixes: 39d62336f5c12 ("s390/pai: add support for cryptography counters")
Acked-by: Sumanth Korikkar <sumanthk@linux.ibm.com>
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>

diff --git a/arch/s390/kernel/perf_pai_crypto.c b/arch/s390/kernel/perf_pai_crypto.c
index f373a1009c456e80ffefcfc8c10754ac166d826a..9455f213dc20216b0e312e42a996b9f2052cd058 100644 (file)
--- a/arch/s390/kernel/perf_pai_crypto.c
+++ b/arch/s390/kernel/perf_pai_crypto.c
@@ -285,10 +285,10 @@ static int paicrypt_event_init(struct perf_event *event)
        /* PAI crypto PMU registered as PERF_TYPE_RAW, check event type */
        if (a->type != PERF_TYPE_RAW && event->pmu->type != a->type)
                return -ENOENT;
-       /* PAI crypto event must be in valid range */
+       /* PAI crypto event must be in valid range, try others if not */
        if (a->config < PAI_CRYPTO_BASE ||
            a->config > PAI_CRYPTO_BASE + paicrypt_cnt)
-               return -EINVAL;
+               return -ENOENT;
        /* Allow only CRYPTO_ALL for sampling */
        if (a->sample_period && a->config != PAI_CRYPTO_BASE)
                return -EINVAL;

diff --git a/arch/s390/kernel/perf_pai_ext.c b/arch/s390/kernel/perf_pai_ext.c
index d827473e7f87f8063e5aa1505f4feebcc1548e91..7b32935273ced17a2c0a3e5ccb2d3d667b2424ae 100644 (file)
--- a/arch/s390/kernel/perf_pai_ext.c
+++ b/arch/s390/kernel/perf_pai_ext.c
@@ -265,7 +265,7 @@ static int paiext_event_valid(struct perf_event *event)
                event->hw.config_base = offsetof(struct paiext_cb, acc);
                return 0;
        }
-       return -EINVAL;
+       return -ENOENT;
 }
 
 /* Might be called on different CPU than the one the event is intended for. */