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-rw-r--r--arch/arm/kernel/ecard.c1
-rw-r--r--arch/arm/kernel/perf_event.c49
-rw-r--r--arch/arm/kernel/perf_event_v6.c22
-rw-r--r--arch/arm/kernel/perf_event_v7.c11
-rw-r--r--arch/arm/kernel/perf_event_xscale.c20
-rw-r--r--arch/arm/kernel/process.c4
-rw-r--r--arch/arm/kernel/smp.c7
7 files changed, 69 insertions, 45 deletions
diff --git a/arch/arm/kernel/ecard.c b/arch/arm/kernel/ecard.c
index 4dd0edab6a6..1651d495074 100644
--- a/arch/arm/kernel/ecard.c
+++ b/arch/arm/kernel/ecard.c
@@ -242,6 +242,7 @@ static void ecard_init_pgtables(struct mm_struct *mm)
memcpy(dst_pgd, src_pgd, sizeof(pgd_t) * (EASI_SIZE / PGDIR_SIZE));
+ vma.vm_flags = VM_EXEC;
vma.vm_mm = mm;
flush_tlb_range(&vma, IO_START, IO_START + IO_SIZE);
diff --git a/arch/arm/kernel/perf_event.c b/arch/arm/kernel/perf_event.c
index 5bb91bf3d47..8a89d3b7626 100644
--- a/arch/arm/kernel/perf_event.c
+++ b/arch/arm/kernel/perf_event.c
@@ -180,7 +180,7 @@ armpmu_event_set_period(struct perf_event *event,
u64
armpmu_event_update(struct perf_event *event,
struct hw_perf_event *hwc,
- int idx, int overflow)
+ int idx)
{
struct arm_pmu *armpmu = to_arm_pmu(event->pmu);
u64 delta, prev_raw_count, new_raw_count;
@@ -193,13 +193,7 @@ again:
new_raw_count) != prev_raw_count)
goto again;
- new_raw_count &= armpmu->max_period;
- prev_raw_count &= armpmu->max_period;
-
- if (overflow)
- delta = armpmu->max_period - prev_raw_count + new_raw_count + 1;
- else
- delta = new_raw_count - prev_raw_count;
+ delta = (new_raw_count - prev_raw_count) & armpmu->max_period;
local64_add(delta, &event->count);
local64_sub(delta, &hwc->period_left);
@@ -216,7 +210,7 @@ armpmu_read(struct perf_event *event)
if (hwc->idx < 0)
return;
- armpmu_event_update(event, hwc, hwc->idx, 0);
+ armpmu_event_update(event, hwc, hwc->idx);
}
static void
@@ -232,7 +226,7 @@ armpmu_stop(struct perf_event *event, int flags)
if (!(hwc->state & PERF_HES_STOPPED)) {
armpmu->disable(hwc, hwc->idx);
barrier(); /* why? */
- armpmu_event_update(event, hwc, hwc->idx, 0);
+ armpmu_event_update(event, hwc, hwc->idx);
hwc->state |= PERF_HES_STOPPED | PERF_HES_UPTODATE;
}
}
@@ -518,7 +512,13 @@ __hw_perf_event_init(struct perf_event *event)
hwc->config_base |= (unsigned long)mapping;
if (!hwc->sample_period) {
- hwc->sample_period = armpmu->max_period;
+ /*
+ * For non-sampling runs, limit the sample_period to half
+ * of the counter width. That way, the new counter value
+ * is far less likely to overtake the previous one unless
+ * you have some serious IRQ latency issues.
+ */
+ hwc->sample_period = armpmu->max_period >> 1;
hwc->last_period = hwc->sample_period;
local64_set(&hwc->period_left, hwc->sample_period);
}
@@ -539,6 +539,10 @@ static int armpmu_event_init(struct perf_event *event)
int err = 0;
atomic_t *active_events = &armpmu->active_events;
+ /* does not support taken branch sampling */
+ if (has_branch_stack(event))
+ return -EOPNOTSUPP;
+
if (armpmu->map_event(event) == -ENOENT)
return -ENOENT;
@@ -680,6 +684,28 @@ static void __init cpu_pmu_init(struct arm_pmu *armpmu)
}
/*
+ * PMU hardware loses all context when a CPU goes offline.
+ * When a CPU is hotplugged back in, since some hardware registers are
+ * UNKNOWN at reset, the PMU must be explicitly reset to avoid reading
+ * junk values out of them.
+ */
+static int __cpuinit pmu_cpu_notify(struct notifier_block *b,
+ unsigned long action, void *hcpu)
+{
+ if ((action & ~CPU_TASKS_FROZEN) != CPU_STARTING)
+ return NOTIFY_DONE;
+
+ if (cpu_pmu && cpu_pmu->reset)
+ cpu_pmu->reset(NULL);
+
+ return NOTIFY_OK;
+}
+
+static struct notifier_block __cpuinitdata pmu_cpu_notifier = {
+ .notifier_call = pmu_cpu_notify,
+};
+
+/*
* CPU PMU identification and registration.
*/
static int __init
@@ -730,6 +756,7 @@ init_hw_perf_events(void)
pr_info("enabled with %s PMU driver, %d counters available\n",
cpu_pmu->name, cpu_pmu->num_events);
cpu_pmu_init(cpu_pmu);
+ register_cpu_notifier(&pmu_cpu_notifier);
armpmu_register(cpu_pmu, "cpu", PERF_TYPE_RAW);
} else {
pr_info("no hardware support available\n");
diff --git a/arch/arm/kernel/perf_event_v6.c b/arch/arm/kernel/perf_event_v6.c
index 533be9930ec..b78af0cc6ef 100644
--- a/arch/arm/kernel/perf_event_v6.c
+++ b/arch/arm/kernel/perf_event_v6.c
@@ -467,23 +467,6 @@ armv6pmu_enable_event(struct hw_perf_event *hwc,
raw_spin_unlock_irqrestore(&events->pmu_lock, flags);
}
-static int counter_is_active(unsigned long pmcr, int idx)
-{
- unsigned long mask = 0;
- if (idx == ARMV6_CYCLE_COUNTER)
- mask = ARMV6_PMCR_CCOUNT_IEN;
- else if (idx == ARMV6_COUNTER0)
- mask = ARMV6_PMCR_COUNT0_IEN;
- else if (idx == ARMV6_COUNTER1)
- mask = ARMV6_PMCR_COUNT1_IEN;
-
- if (mask)
- return pmcr & mask;
-
- WARN_ONCE(1, "invalid counter number (%d)\n", idx);
- return 0;
-}
-
static irqreturn_t
armv6pmu_handle_irq(int irq_num,
void *dev)
@@ -513,7 +496,8 @@ armv6pmu_handle_irq(int irq_num,
struct perf_event *event = cpuc->events[idx];
struct hw_perf_event *hwc;
- if (!counter_is_active(pmcr, idx))
+ /* Ignore if we don't have an event. */
+ if (!event)
continue;
/*
@@ -524,7 +508,7 @@ armv6pmu_handle_irq(int irq_num,
continue;
hwc = &event->hw;
- armpmu_event_update(event, hwc, idx, 1);
+ armpmu_event_update(event, hwc, idx);
data.period = event->hw.last_period;
if (!armpmu_event_set_period(event, hwc, idx))
continue;
diff --git a/arch/arm/kernel/perf_event_v7.c b/arch/arm/kernel/perf_event_v7.c
index 6933244c68f..4d7095af2ab 100644
--- a/arch/arm/kernel/perf_event_v7.c
+++ b/arch/arm/kernel/perf_event_v7.c
@@ -809,6 +809,11 @@ static inline int armv7_pmnc_disable_intens(int idx)
counter = ARMV7_IDX_TO_COUNTER(idx);
asm volatile("mcr p15, 0, %0, c9, c14, 2" : : "r" (BIT(counter)));
+ isb();
+ /* Clear the overflow flag in case an interrupt is pending. */
+ asm volatile("mcr p15, 0, %0, c9, c12, 3" : : "r" (BIT(counter)));
+ isb();
+
return idx;
}
@@ -955,6 +960,10 @@ static irqreturn_t armv7pmu_handle_irq(int irq_num, void *dev)
struct perf_event *event = cpuc->events[idx];
struct hw_perf_event *hwc;
+ /* Ignore if we don't have an event. */
+ if (!event)
+ continue;
+
/*
* We have a single interrupt for all counters. Check that
* each counter has overflowed before we process it.
@@ -963,7 +972,7 @@ static irqreturn_t armv7pmu_handle_irq(int irq_num, void *dev)
continue;
hwc = &event->hw;
- armpmu_event_update(event, hwc, idx, 1);
+ armpmu_event_update(event, hwc, idx);
data.period = event->hw.last_period;
if (!armpmu_event_set_period(event, hwc, idx))
continue;
diff --git a/arch/arm/kernel/perf_event_xscale.c b/arch/arm/kernel/perf_event_xscale.c
index 3b99d826982..71a21e6712f 100644
--- a/arch/arm/kernel/perf_event_xscale.c
+++ b/arch/arm/kernel/perf_event_xscale.c
@@ -255,11 +255,14 @@ xscale1pmu_handle_irq(int irq_num, void *dev)
struct perf_event *event = cpuc->events[idx];
struct hw_perf_event *hwc;
+ if (!event)
+ continue;
+
if (!xscale1_pmnc_counter_has_overflowed(pmnc, idx))
continue;
hwc = &event->hw;
- armpmu_event_update(event, hwc, idx, 1);
+ armpmu_event_update(event, hwc, idx);
data.period = event->hw.last_period;
if (!armpmu_event_set_period(event, hwc, idx))
continue;
@@ -592,11 +595,14 @@ xscale2pmu_handle_irq(int irq_num, void *dev)
struct perf_event *event = cpuc->events[idx];
struct hw_perf_event *hwc;
- if (!xscale2_pmnc_counter_has_overflowed(pmnc, idx))
+ if (!event)
+ continue;
+
+ if (!xscale2_pmnc_counter_has_overflowed(of_flags, idx))
continue;
hwc = &event->hw;
- armpmu_event_update(event, hwc, idx, 1);
+ armpmu_event_update(event, hwc, idx);
data.period = event->hw.last_period;
if (!armpmu_event_set_period(event, hwc, idx))
continue;
@@ -663,7 +669,7 @@ xscale2pmu_enable_event(struct hw_perf_event *hwc, int idx)
static void
xscale2pmu_disable_event(struct hw_perf_event *hwc, int idx)
{
- unsigned long flags, ien, evtsel;
+ unsigned long flags, ien, evtsel, of_flags;
struct pmu_hw_events *events = cpu_pmu->get_hw_events();
ien = xscale2pmu_read_int_enable();
@@ -672,26 +678,31 @@ xscale2pmu_disable_event(struct hw_perf_event *hwc, int idx)
switch (idx) {
case XSCALE_CYCLE_COUNTER:
ien &= ~XSCALE2_CCOUNT_INT_EN;
+ of_flags = XSCALE2_CCOUNT_OVERFLOW;
break;
case XSCALE_COUNTER0:
ien &= ~XSCALE2_COUNT0_INT_EN;
evtsel &= ~XSCALE2_COUNT0_EVT_MASK;
evtsel |= XSCALE_PERFCTR_UNUSED << XSCALE2_COUNT0_EVT_SHFT;
+ of_flags = XSCALE2_COUNT0_OVERFLOW;
break;
case XSCALE_COUNTER1:
ien &= ~XSCALE2_COUNT1_INT_EN;
evtsel &= ~XSCALE2_COUNT1_EVT_MASK;
evtsel |= XSCALE_PERFCTR_UNUSED << XSCALE2_COUNT1_EVT_SHFT;
+ of_flags = XSCALE2_COUNT1_OVERFLOW;
break;
case XSCALE_COUNTER2:
ien &= ~XSCALE2_COUNT2_INT_EN;
evtsel &= ~XSCALE2_COUNT2_EVT_MASK;
evtsel |= XSCALE_PERFCTR_UNUSED << XSCALE2_COUNT2_EVT_SHFT;
+ of_flags = XSCALE2_COUNT2_OVERFLOW;
break;
case XSCALE_COUNTER3:
ien &= ~XSCALE2_COUNT3_INT_EN;
evtsel &= ~XSCALE2_COUNT3_EVT_MASK;
evtsel |= XSCALE_PERFCTR_UNUSED << XSCALE2_COUNT3_EVT_SHFT;
+ of_flags = XSCALE2_COUNT3_OVERFLOW;
break;
default:
WARN_ONCE(1, "invalid counter number (%d)\n", idx);
@@ -701,6 +712,7 @@ xscale2pmu_disable_event(struct hw_perf_event *hwc, int idx)
raw_spin_lock_irqsave(&events->pmu_lock, flags);
xscale2pmu_write_event_select(evtsel);
xscale2pmu_write_int_enable(ien);
+ xscale2pmu_write_overflow_flags(of_flags);
raw_spin_unlock_irqrestore(&events->pmu_lock, flags);
}
diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c
index 971d65c253a..c2ae3cd331f 100644
--- a/arch/arm/kernel/process.c
+++ b/arch/arm/kernel/process.c
@@ -239,9 +239,7 @@ void cpu_idle(void)
leds_event(led_idle_end);
rcu_idle_exit();
tick_nohz_idle_exit();
- preempt_enable_no_resched();
- schedule();
- preempt_disable();
+ schedule_preempt_disabled();
}
}
diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c
index cdeb727527d..d616ed51e7a 100644
--- a/arch/arm/kernel/smp.c
+++ b/arch/arm/kernel/smp.c
@@ -295,13 +295,6 @@ asmlinkage void __cpuinit secondary_start_kernel(void)
*/
percpu_timer_setup();
- while (!cpu_active(cpu))
- cpu_relax();
-
- /*
- * cpu_active bit is set, so it's safe to enalbe interrupts
- * now.
- */
local_irq_enable();
local_fiq_enable();
generated by cgit v1.2.3-18-g5258 (git 2.32.0) at 2024-12-11 08:16:48 +0000