From 869f4f98fafadddb3a871b9513f24a44479d8296 Mon Sep 17 00:00:00 2001 From: Hendrik Brueckner Date: Thu, 25 Oct 2018 16:58:15 +0200 Subject: s390/cpum_cf: introduce kernel_cpumcf_avail() function A preparation to move out common CPU-MF counter facility support functions, first introduce a function that indicates whether the support is ready to use. Signed-off-by: Hendrik Brueckner Signed-off-by: Martin Schwidefsky --- arch/s390/kernel/perf_cpum_cf.c | 20 +++++++++++++++++--- 1 file changed, 17 insertions(+), 3 deletions(-) (limited to 'arch/s390/kernel') diff --git a/arch/s390/kernel/perf_cpum_cf.c b/arch/s390/kernel/perf_cpum_cf.c index c05f69142ce4..ab4b8c904d01 100644 --- a/arch/s390/kernel/perf_cpum_cf.c +++ b/arch/s390/kernel/perf_cpum_cf.c @@ -33,6 +33,9 @@ DEFINE_PER_CPU(struct cpu_cf_events, cpu_cf_events) = { .txn_flags = 0, }; +/* Indicator whether the CPU-Measurement Counter Facility Support is ready */ +static bool cpum_cf_initalized; + static enum cpumf_ctr_set get_counter_set(u64 event) { int set = CPUMF_CTR_SET_MAX; @@ -233,6 +236,12 @@ static void setup_pmc_cpu(void *flags) lcctl(0); } +bool kernel_cpumcf_avail(void) +{ + return cpum_cf_initalized; +} +EXPORT_SYMBOL(kernel_cpumcf_avail); + /* Reserve/release functions for sharing perf hardware */ static DEFINE_SPINLOCK(cpumcf_owner_lock); static void *cpumcf_owner; @@ -709,8 +718,13 @@ static int __init cpumf_pmu_init(void) cpumf_measurement_alert); return rc; } - return cpuhp_setup_state(CPUHP_AP_PERF_S390_CF_ONLINE, - "perf/s390/cf:online", - s390_pmu_online_cpu, s390_pmu_offline_cpu); + + rc = cpuhp_setup_state(CPUHP_AP_PERF_S390_CF_ONLINE, + "perf/s390/cf:online", + s390_pmu_online_cpu, s390_pmu_offline_cpu); + if (!rc) + cpum_cf_initalized = true; + + return rc; } early_initcall(cpumf_pmu_init); -- cgit v1.2.3