diff options
Diffstat (limited to 'kernel/perf_event.c')
| -rw-r--r-- | kernel/perf_event.c | 64 |
1 files changed, 52 insertions, 12 deletions
diff --git a/kernel/perf_event.c b/kernel/perf_event.c index 5ed0c06765bb..8ef4ba3bcb1f 100644 --- a/kernel/perf_event.c +++ b/kernel/perf_event.c @@ -674,21 +674,14 @@ group_sched_in(struct perf_event *group_event, { struct perf_event *event, *partial_group = NULL; struct pmu *pmu = group_event->pmu; - bool txn = false; if (group_event->state == PERF_EVENT_STATE_OFF) return 0; - /* Check if group transaction availabe */ - if (pmu->start_txn) - txn = true; - - if (txn) - pmu->start_txn(pmu); + pmu->start_txn(pmu); if (event_sched_in(group_event, cpuctx, ctx)) { - if (txn) - pmu->cancel_txn(pmu); + pmu->cancel_txn(pmu); return -EAGAIN; } @@ -702,7 +695,7 @@ group_sched_in(struct perf_event *group_event, } } - if (!txn || !pmu->commit_txn(pmu)) + if (!pmu->commit_txn(pmu)) return 0; group_error: @@ -717,8 +710,7 @@ group_error: } event_sched_out(group_event, cpuctx, ctx); - if (txn) - pmu->cancel_txn(pmu); + pmu->cancel_txn(pmu); return -EAGAIN; } @@ -4965,6 +4957,31 @@ static LIST_HEAD(pmus); static DEFINE_MUTEX(pmus_lock); static struct srcu_struct pmus_srcu; +static void perf_pmu_nop_void(struct pmu *pmu) +{ +} + +static int perf_pmu_nop_int(struct pmu *pmu) +{ + return 0; +} + +static void perf_pmu_start_txn(struct pmu *pmu) +{ + perf_pmu_disable(pmu); +} + +static int perf_pmu_commit_txn(struct pmu *pmu) +{ + perf_pmu_enable(pmu); + return 0; +} + +static void perf_pmu_cancel_txn(struct pmu *pmu) +{ + perf_pmu_enable(pmu); +} + int perf_pmu_register(struct pmu *pmu) { int ret; @@ -4974,6 +4991,29 @@ int perf_pmu_register(struct pmu *pmu) pmu->pmu_disable_count = alloc_percpu(int); if (!pmu->pmu_disable_count) goto unlock; + + if (!pmu->start_txn) { + if (pmu->pmu_enable) { + /* + * If we have pmu_enable/pmu_disable calls, install + * transaction stubs that use that to try and batch + * hardware accesses. + */ + pmu->start_txn = perf_pmu_start_txn; + pmu->commit_txn = perf_pmu_commit_txn; + pmu->cancel_txn = perf_pmu_cancel_txn; + } else { + pmu->start_txn = perf_pmu_nop_void; + pmu->commit_txn = perf_pmu_nop_int; + pmu->cancel_txn = perf_pmu_nop_void; + } + } + + if (!pmu->pmu_enable) { + pmu->pmu_enable = perf_pmu_nop_void; + pmu->pmu_disable = perf_pmu_nop_void; + } + list_add_rcu(&pmu->entry, &pmus); ret = 0; unlock: |