s390/cpum_cf_diag: Add support for s390 counter facility diagnostic trace

Introduce a PMU device named cpum_cf_diag. It extracts the
values of all counters in all authorized counter sets and stores
them as event raw data. This is done with the STORE CPU COUNTER
MULTIPLE instruction to speed up access. All counter sets
fit into one buffer. The values of each counter are taken
when the event is started on the performance sub-system and when
the event is stopped.
This results in counter values available at the start and
at the end of the measurement time frame. The difference is
calculated for each counter. The differences of all
counters are then saved as event raw data in the perf.data
file.

The counter values are accompanied by the time stamps
when the counter set was started and when the counter set
was stopped. This data is part of a trailer entry which
describes the time frame, counter set version numbers,
CPU speed, and machine type for later analysis.

Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Reviewed-by: Hendrik Brueckner <brueckner@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 26 insertions, 0 deletions

diff --git a/arch/s390/include/asm/cpu_mcf.h b/arch/s390/include/asm/cpu_mcf.h
index 0c236d1a7aee..649b9fc60685 100644
--- a/arch/s390/include/asm/cpu_mcf.h
+++ b/arch/s390/include/asm/cpu_mcf.h
@@ -49,6 +49,26 @@ static inline void ctr_set_stop(u64 *state, int ctr_set)
 	*state &= ~(cpumf_ctr_ctl[ctr_set] << CPUMF_LCCTL_ACTCTL_SHIFT);
 }
 
+static inline void ctr_set_multiple_enable(u64 *state, u64 ctrsets)
+{
+	*state |= ctrsets << CPUMF_LCCTL_ENABLE_SHIFT;
+}
+
+static inline void ctr_set_multiple_disable(u64 *state, u64 ctrsets)
+{
+	*state &= ~(ctrsets << CPUMF_LCCTL_ENABLE_SHIFT);
+}
+
+static inline void ctr_set_multiple_start(u64 *state, u64 ctrsets)
+{
+	*state |= ctrsets << CPUMF_LCCTL_ACTCTL_SHIFT;
+}
+
+static inline void ctr_set_multiple_stop(u64 *state, u64 ctrsets)
+{
+	*state &= ~(ctrsets << CPUMF_LCCTL_ACTCTL_SHIFT);
+}
+
 static inline int ctr_stcctm(enum cpumf_ctr_set set, u64 range, u64 *dest)
 {
 	switch (set) {
@@ -97,4 +117,10 @@ static inline void kernel_cpumcf_end(void)
 	preempt_enable();
 }
 
+/* Return true if store counter set multiple instruction is available */
+static inline int stccm_avail(void)
+{
+	return test_facility(142);
+}
+
 #endif /* _ASM_S390_CPU_MCF_H */