diff options
Diffstat (limited to 'arch/s390/kernel/perf_cpum_cf.c')
-rw-r--r-- | arch/s390/kernel/perf_cpum_cf.c | 47 |
1 files changed, 38 insertions, 9 deletions
diff --git a/arch/s390/kernel/perf_cpum_cf.c b/arch/s390/kernel/perf_cpum_cf.c index 56fdad479115..929c147e07b4 100644 --- a/arch/s390/kernel/perf_cpum_cf.c +++ b/arch/s390/kernel/perf_cpum_cf.c @@ -72,6 +72,7 @@ struct cpu_hw_events { atomic_t ctr_set[CPUMF_CTR_SET_MAX]; u64 state, tx_state; unsigned int flags; + unsigned int txn_flags; }; static DEFINE_PER_CPU(struct cpu_hw_events, cpu_hw_events) = { .ctr_set = { @@ -82,6 +83,7 @@ static DEFINE_PER_CPU(struct cpu_hw_events, cpu_hw_events) = { }, .state = 0, .flags = 0, + .txn_flags = 0, }; static int get_counter_set(u64 event) @@ -157,10 +159,14 @@ static int validate_ctr_auth(const struct hw_perf_event *hwc) cpuhw = &get_cpu_var(cpu_hw_events); - /* check authorization for cpu counter sets */ + /* Check authorization for cpu counter sets. + * If the particular CPU counter set is not authorized, + * return with -ENOENT in order to fall back to other + * PMUs that might suffice the event request. + */ ctrs_state = cpumf_state_ctl[hwc->config_base]; if (!(ctrs_state & cpuhw->info.auth_ctl)) - err = -EPERM; + err = -ENOENT; put_cpu_var(cpu_hw_events); return err; @@ -534,9 +540,9 @@ static int cpumf_pmu_add(struct perf_event *event, int flags) * For group events transaction, the authorization check is * done in cpumf_pmu_commit_txn(). */ - if (!(cpuhw->flags & PERF_EVENT_TXN)) + if (!(cpuhw->txn_flags & PERF_PMU_TXN_ADD)) if (validate_ctr_auth(&event->hw)) - return -EPERM; + return -ENOENT; ctr_set_enable(&cpuhw->state, event->hw.config_base); event->hw.state = PERF_HES_UPTODATE | PERF_HES_STOPPED; @@ -572,13 +578,22 @@ static void cpumf_pmu_del(struct perf_event *event, int flags) /* * Start group events scheduling transaction. * Set flags to perform a single test at commit time. + * + * We only support PERF_PMU_TXN_ADD transactions. Save the + * transaction flags but otherwise ignore non-PERF_PMU_TXN_ADD + * transactions. */ -static void cpumf_pmu_start_txn(struct pmu *pmu) +static void cpumf_pmu_start_txn(struct pmu *pmu, unsigned int txn_flags) { struct cpu_hw_events *cpuhw = this_cpu_ptr(&cpu_hw_events); + WARN_ON_ONCE(cpuhw->txn_flags); /* txn already in flight */ + + cpuhw->txn_flags = txn_flags; + if (txn_flags & ~PERF_PMU_TXN_ADD) + return; + perf_pmu_disable(pmu); - cpuhw->flags |= PERF_EVENT_TXN; cpuhw->tx_state = cpuhw->state; } @@ -589,11 +604,18 @@ static void cpumf_pmu_start_txn(struct pmu *pmu) */ static void cpumf_pmu_cancel_txn(struct pmu *pmu) { + unsigned int txn_flags; struct cpu_hw_events *cpuhw = this_cpu_ptr(&cpu_hw_events); + WARN_ON_ONCE(!cpuhw->txn_flags); /* no txn in flight */ + + txn_flags = cpuhw->txn_flags; + cpuhw->txn_flags = 0; + if (txn_flags & ~PERF_PMU_TXN_ADD) + return; + WARN_ON(cpuhw->tx_state != cpuhw->state); - cpuhw->flags &= ~PERF_EVENT_TXN; perf_pmu_enable(pmu); } @@ -607,13 +629,20 @@ static int cpumf_pmu_commit_txn(struct pmu *pmu) struct cpu_hw_events *cpuhw = this_cpu_ptr(&cpu_hw_events); u64 state; + WARN_ON_ONCE(!cpuhw->txn_flags); /* no txn in flight */ + + if (cpuhw->txn_flags & ~PERF_PMU_TXN_ADD) { + cpuhw->txn_flags = 0; + return 0; + } + /* check if the updated state can be scheduled */ state = cpuhw->state & ~((1 << CPUMF_LCCTL_ENABLE_SHIFT) - 1); state >>= CPUMF_LCCTL_ENABLE_SHIFT; if ((state & cpuhw->info.auth_ctl) != state) - return -EPERM; + return -ENOENT; - cpuhw->flags &= ~PERF_EVENT_TXN; + cpuhw->txn_flags = 0; perf_pmu_enable(pmu); return 0; } |