diff options
author | Vineet Gupta <vgupta@synopsys.com> | 2015-05-09 18:27:30 +0530 |
---|---|---|
committer | Vineet Gupta <vgupta@synopsys.com> | 2017-11-21 15:20:31 -0800 |
commit | 4d431290402c8d867af7ba45ee75407d68748c4a (patch) | |
tree | 5105c19adb9b0834c359706f0a41b1a96b34fda2 /arch/arc/kernel | |
parent | ff64d695f92123f7d341473921a46add51a44a87 (diff) | |
download | linux-4d431290402c8d867af7ba45ee75407d68748c4a.tar.bz2 |
ARCv2: perf: tweak overflow interrupt
Current perf ISR loops thru all 32 counters, checking for each if it
caused the interrupt. Instead only loop thru counters which actually
interrupted (typically 1).
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Diffstat (limited to 'arch/arc/kernel')
-rw-r--r-- | arch/arc/kernel/perf_event.c | 24 |
1 files changed, 14 insertions, 10 deletions
diff --git a/arch/arc/kernel/perf_event.c b/arch/arc/kernel/perf_event.c index 2ce24e74f879..0eaa132a2c90 100644 --- a/arch/arc/kernel/perf_event.c +++ b/arch/arc/kernel/perf_event.c @@ -377,21 +377,22 @@ static irqreturn_t arc_pmu_intr(int irq, void *dev) struct perf_sample_data data; struct arc_pmu_cpu *pmu_cpu = this_cpu_ptr(&arc_pmu_cpu); struct pt_regs *regs; - int active_ints; + unsigned int active_ints; int idx; arc_pmu_disable(&arc_pmu->pmu); active_ints = read_aux_reg(ARC_REG_PCT_INT_ACT); + if (!active_ints) + goto done; regs = get_irq_regs(); - for (idx = 0; idx < arc_pmu->n_counters; idx++) { - struct perf_event *event = pmu_cpu->act_counter[idx]; + do { + struct perf_event *event; struct hw_perf_event *hwc; - if (!(active_ints & (1 << idx))) - continue; + idx = __ffs(active_ints); /* Reset interrupt flag by writing of 1 */ write_aux_reg(ARC_REG_PCT_INT_ACT, 1 << idx); @@ -404,19 +405,22 @@ static irqreturn_t arc_pmu_intr(int irq, void *dev) write_aux_reg(ARC_REG_PCT_INT_CTRL, read_aux_reg(ARC_REG_PCT_INT_CTRL) | (1 << idx)); + event = pmu_cpu->act_counter[idx]; hwc = &event->hw; WARN_ON_ONCE(hwc->idx != idx); arc_perf_event_update(event, &event->hw, event->hw.idx); perf_sample_data_init(&data, 0, hwc->last_period); - if (!arc_pmu_event_set_period(event)) - continue; + if (arc_pmu_event_set_period(event)) { + if (perf_event_overflow(event, &data, regs)) + arc_pmu_stop(event, 0); + } - if (perf_event_overflow(event, &data, regs)) - arc_pmu_stop(event, 0); - } + active_ints &= ~(1U << idx); + } while (active_ints); +done: arc_pmu_enable(&arc_pmu->pmu); return IRQ_HANDLED; |