diff options
author | 2016-04-11 10:41:07 +0300 | |
---|---|---|
committer | 2016-04-13 08:17:18 +0300 | |
commit | e09b41010ba33a20a87472ee821fa407a5b8da36 (patch) | |
tree | d10dc367189862e7ca5c592f033dc3726e1df4e3 /kernel/drivers/bus/arm-ccn.c | |
parent | f93b97fd65072de626c074dbe099a1fff05ce060 (diff) |
These changes are the raw update to linux-4.4.6-rt14. Kernel sources
are taken from kernel.org, and rt patch from the rt wiki download page.
During the rebasing, the following patch collided:
Force tick interrupt and get rid of softirq magic(I70131fb85).
Collisions have been removed because its logic was found on the
source already.
Change-Id: I7f57a4081d9deaa0d9ccfc41a6c8daccdee3b769
Signed-off-by: José Pekkarinen <jose.pekkarinen@nokia.com>
Diffstat (limited to 'kernel/drivers/bus/arm-ccn.c')
-rw-r--r-- | kernel/drivers/bus/arm-ccn.c | 269 |
1 files changed, 214 insertions, 55 deletions
diff --git a/kernel/drivers/bus/arm-ccn.c b/kernel/drivers/bus/arm-ccn.c index 60397ec77..7082c7268 100644 --- a/kernel/drivers/bus/arm-ccn.c +++ b/kernel/drivers/bus/arm-ccn.c @@ -166,13 +166,17 @@ struct arm_ccn_dt { struct hrtimer hrtimer; + cpumask_t cpu; + struct notifier_block cpu_nb; + struct pmu pmu; }; struct arm_ccn { struct device *dev; void __iomem *base; - unsigned irq_used:1; + unsigned int irq; + unsigned sbas_present:1; unsigned sbsx_present:1; @@ -336,6 +340,23 @@ static ssize_t arm_ccn_pmu_event_show(struct device *dev, if (event->mask) res += snprintf(buf + res, PAGE_SIZE - res, ",mask=0x%x", event->mask); + + /* Arguments required by an event */ + switch (event->type) { + case CCN_TYPE_CYCLES: + break; + case CCN_TYPE_XP: + res += snprintf(buf + res, PAGE_SIZE - res, + ",xp=?,port=?,vc=?,dir=?"); + if (event->event == CCN_EVENT_WATCHPOINT) + res += snprintf(buf + res, PAGE_SIZE - res, + ",cmp_l=?,cmp_h=?,mask=?"); + break; + default: + res += snprintf(buf + res, PAGE_SIZE - res, ",node=?"); + break; + } + res += snprintf(buf + res, PAGE_SIZE - res, "\n"); return res; @@ -521,6 +542,25 @@ static struct attribute_group arm_ccn_pmu_cmp_mask_attr_group = { .attrs = arm_ccn_pmu_cmp_mask_attrs, }; +static ssize_t arm_ccn_pmu_cpumask_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct arm_ccn *ccn = pmu_to_arm_ccn(dev_get_drvdata(dev)); + + return cpumap_print_to_pagebuf(true, buf, &ccn->dt.cpu); +} + +static struct device_attribute arm_ccn_pmu_cpumask_attr = + __ATTR(cpumask, S_IRUGO, arm_ccn_pmu_cpumask_show, NULL); + +static struct attribute *arm_ccn_pmu_cpumask_attrs[] = { + &arm_ccn_pmu_cpumask_attr.attr, + NULL, +}; + +static struct attribute_group arm_ccn_pmu_cpumask_attr_group = { + .attrs = arm_ccn_pmu_cpumask_attrs, +}; /* * Default poll period is 10ms, which is way over the top anyway, @@ -542,6 +582,7 @@ static const struct attribute_group *arm_ccn_pmu_attr_groups[] = { &arm_ccn_pmu_events_attr_group, &arm_ccn_pmu_format_attr_group, &arm_ccn_pmu_cmp_mask_attr_group, + &arm_ccn_pmu_cpumask_attr_group, NULL }; @@ -587,7 +628,65 @@ static int arm_ccn_pmu_type_eq(u32 a, u32 b) return 0; } -static void arm_ccn_pmu_event_destroy(struct perf_event *event) +static int arm_ccn_pmu_event_alloc(struct perf_event *event) +{ + struct arm_ccn *ccn = pmu_to_arm_ccn(event->pmu); + struct hw_perf_event *hw = &event->hw; + u32 node_xp, type, event_id; + struct arm_ccn_component *source; + int bit; + + node_xp = CCN_CONFIG_NODE(event->attr.config); + type = CCN_CONFIG_TYPE(event->attr.config); + event_id = CCN_CONFIG_EVENT(event->attr.config); + + /* Allocate the cycle counter */ + if (type == CCN_TYPE_CYCLES) { + if (test_and_set_bit(CCN_IDX_PMU_CYCLE_COUNTER, + ccn->dt.pmu_counters_mask)) + return -EAGAIN; + + hw->idx = CCN_IDX_PMU_CYCLE_COUNTER; + ccn->dt.pmu_counters[CCN_IDX_PMU_CYCLE_COUNTER].event = event; + + return 0; + } + + /* Allocate an event counter */ + hw->idx = arm_ccn_pmu_alloc_bit(ccn->dt.pmu_counters_mask, + CCN_NUM_PMU_EVENT_COUNTERS); + if (hw->idx < 0) { + dev_dbg(ccn->dev, "No more counters available!\n"); + return -EAGAIN; + } + + if (type == CCN_TYPE_XP) + source = &ccn->xp[node_xp]; + else + source = &ccn->node[node_xp]; + ccn->dt.pmu_counters[hw->idx].source = source; + + /* Allocate an event source or a watchpoint */ + if (type == CCN_TYPE_XP && event_id == CCN_EVENT_WATCHPOINT) + bit = arm_ccn_pmu_alloc_bit(source->xp.dt_cmp_mask, + CCN_NUM_XP_WATCHPOINTS); + else + bit = arm_ccn_pmu_alloc_bit(source->pmu_events_mask, + CCN_NUM_PMU_EVENTS); + if (bit < 0) { + dev_dbg(ccn->dev, "No more event sources/watchpoints on node/XP %d!\n", + node_xp); + clear_bit(hw->idx, ccn->dt.pmu_counters_mask); + return -EAGAIN; + } + hw->config_base = bit; + + ccn->dt.pmu_counters[hw->idx].event = event; + + return 0; +} + +static void arm_ccn_pmu_event_release(struct perf_event *event) { struct arm_ccn *ccn = pmu_to_arm_ccn(event->pmu); struct hw_perf_event *hw = &event->hw; @@ -616,15 +715,14 @@ static int arm_ccn_pmu_event_init(struct perf_event *event) struct arm_ccn *ccn; struct hw_perf_event *hw = &event->hw; u32 node_xp, type, event_id; - int valid, bit; - struct arm_ccn_component *source; + int valid; int i; + struct perf_event *sibling; if (event->attr.type != event->pmu->type) return -ENOENT; ccn = pmu_to_arm_ccn(event->pmu); - event->destroy = arm_ccn_pmu_event_destroy; if (hw->sample_period) { dev_warn(ccn->dev, "Sampling not supported!\n"); @@ -642,6 +740,16 @@ static int arm_ccn_pmu_event_init(struct perf_event *event) dev_warn(ccn->dev, "Can't provide per-task data!\n"); return -EOPNOTSUPP; } + /* + * Many perf core operations (eg. events rotation) operate on a + * single CPU context. This is obvious for CPU PMUs, where one + * expects the same sets of events being observed on all CPUs, + * but can lead to issues for off-core PMUs, like CCN, where each + * event could be theoretically assigned to a different CPU. To + * mitigate this, we enforce CPU assignment to one, selected + * processor (the one described in the "cpumask" attribute). + */ + event->cpu = cpumask_first(&ccn->dt.cpu); node_xp = CCN_CONFIG_NODE(event->attr.config); type = CCN_CONFIG_TYPE(event->attr.config); @@ -711,48 +819,20 @@ static int arm_ccn_pmu_event_init(struct perf_event *event) node_xp, type, port); } - /* Allocate the cycle counter */ - if (type == CCN_TYPE_CYCLES) { - if (test_and_set_bit(CCN_IDX_PMU_CYCLE_COUNTER, - ccn->dt.pmu_counters_mask)) - return -EAGAIN; - - hw->idx = CCN_IDX_PMU_CYCLE_COUNTER; - ccn->dt.pmu_counters[CCN_IDX_PMU_CYCLE_COUNTER].event = event; - - return 0; - } - - /* Allocate an event counter */ - hw->idx = arm_ccn_pmu_alloc_bit(ccn->dt.pmu_counters_mask, - CCN_NUM_PMU_EVENT_COUNTERS); - if (hw->idx < 0) { - dev_warn(ccn->dev, "No more counters available!\n"); - return -EAGAIN; - } - - if (type == CCN_TYPE_XP) - source = &ccn->xp[node_xp]; - else - source = &ccn->node[node_xp]; - ccn->dt.pmu_counters[hw->idx].source = source; - - /* Allocate an event source or a watchpoint */ - if (type == CCN_TYPE_XP && event_id == CCN_EVENT_WATCHPOINT) - bit = arm_ccn_pmu_alloc_bit(source->xp.dt_cmp_mask, - CCN_NUM_XP_WATCHPOINTS); - else - bit = arm_ccn_pmu_alloc_bit(source->pmu_events_mask, - CCN_NUM_PMU_EVENTS); - if (bit < 0) { - dev_warn(ccn->dev, "No more event sources/watchpoints on node/XP %d!\n", - node_xp); - clear_bit(hw->idx, ccn->dt.pmu_counters_mask); - return -EAGAIN; - } - hw->config_base = bit; + /* + * We must NOT create groups containing mixed PMUs, although software + * events are acceptable (for example to create a CCN group + * periodically read when a hrtimer aka cpu-clock leader triggers). + */ + if (event->group_leader->pmu != event->pmu && + !is_software_event(event->group_leader)) + return -EINVAL; - ccn->dt.pmu_counters[hw->idx].event = event; + list_for_each_entry(sibling, &event->group_leader->sibling_list, + group_entry) + if (sibling->pmu != event->pmu && + !is_software_event(sibling)) + return -EINVAL; return 0; } @@ -835,9 +915,14 @@ static void arm_ccn_pmu_event_start(struct perf_event *event, int flags) arm_ccn_pmu_read_counter(ccn, hw->idx)); hw->state = 0; - if (!ccn->irq_used) + /* + * Pin the timer, so that the overflows are handled by the chosen + * event->cpu (this is the same one as presented in "cpumask" + * attribute). + */ + if (!ccn->irq) hrtimer_start(&ccn->dt.hrtimer, arm_ccn_pmu_timer_period(), - HRTIMER_MODE_REL); + HRTIMER_MODE_REL_PINNED); /* Set the DT bus input, engaging the counter */ arm_ccn_pmu_xp_dt_config(event, 1); @@ -852,7 +937,7 @@ static void arm_ccn_pmu_event_stop(struct perf_event *event, int flags) /* Disable counting, setting the DT bus to pass-through mode */ arm_ccn_pmu_xp_dt_config(event, 0); - if (!ccn->irq_used) + if (!ccn->irq) hrtimer_cancel(&ccn->dt.hrtimer); /* Let the DT bus drain */ @@ -1014,8 +1099,13 @@ static void arm_ccn_pmu_event_config(struct perf_event *event) static int arm_ccn_pmu_event_add(struct perf_event *event, int flags) { + int err; struct hw_perf_event *hw = &event->hw; + err = arm_ccn_pmu_event_alloc(event); + if (err) + return err; + arm_ccn_pmu_event_config(event); hw->state = PERF_HES_STOPPED; @@ -1029,6 +1119,8 @@ static int arm_ccn_pmu_event_add(struct perf_event *event, int flags) static void arm_ccn_pmu_event_del(struct perf_event *event, int flags) { arm_ccn_pmu_event_stop(event, PERF_EF_UPDATE); + + arm_ccn_pmu_event_release(event); } static void arm_ccn_pmu_event_read(struct perf_event *event) @@ -1079,12 +1171,40 @@ static enum hrtimer_restart arm_ccn_pmu_timer_handler(struct hrtimer *hrtimer) } +static int arm_ccn_pmu_cpu_notifier(struct notifier_block *nb, + unsigned long action, void *hcpu) +{ + struct arm_ccn_dt *dt = container_of(nb, struct arm_ccn_dt, cpu_nb); + struct arm_ccn *ccn = container_of(dt, struct arm_ccn, dt); + unsigned int cpu = (long)hcpu; /* for (long) see kernel/cpu.c */ + unsigned int target; + + switch (action & ~CPU_TASKS_FROZEN) { + case CPU_DOWN_PREPARE: + if (!cpumask_test_and_clear_cpu(cpu, &dt->cpu)) + break; + target = cpumask_any_but(cpu_online_mask, cpu); + if (target >= nr_cpu_ids) + break; + perf_pmu_migrate_context(&dt->pmu, cpu, target); + cpumask_set_cpu(target, &dt->cpu); + if (ccn->irq) + WARN_ON(irq_set_affinity(ccn->irq, &dt->cpu) != 0); + default: + break; + } + + return NOTIFY_OK; +} + + static DEFINE_IDA(arm_ccn_pmu_ida); static int arm_ccn_pmu_init(struct arm_ccn *ccn) { int i; char *name; + int err; /* Initialize DT subsystem */ ccn->dt.base = ccn->base + CCN_REGION_SIZE; @@ -1136,20 +1256,58 @@ static int arm_ccn_pmu_init(struct arm_ccn *ccn) }; /* No overflow interrupt? Have to use a timer instead. */ - if (!ccn->irq_used) { + if (!ccn->irq) { dev_info(ccn->dev, "No access to interrupts, using timer.\n"); hrtimer_init(&ccn->dt.hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); ccn->dt.hrtimer.function = arm_ccn_pmu_timer_handler; } - return perf_pmu_register(&ccn->dt.pmu, name, -1); + /* Pick one CPU which we will use to collect data from CCN... */ + cpumask_set_cpu(smp_processor_id(), &ccn->dt.cpu); + + /* + * ... and change the selection when it goes offline. Priority is + * picked to have a chance to migrate events before perf is notified. + */ + ccn->dt.cpu_nb.notifier_call = arm_ccn_pmu_cpu_notifier; + ccn->dt.cpu_nb.priority = CPU_PRI_PERF + 1, + err = register_cpu_notifier(&ccn->dt.cpu_nb); + if (err) + goto error_cpu_notifier; + + /* Also make sure that the overflow interrupt is handled by this CPU */ + if (ccn->irq) { + err = irq_set_affinity(ccn->irq, &ccn->dt.cpu); + if (err) { + dev_err(ccn->dev, "Failed to set interrupt affinity!\n"); + goto error_set_affinity; + } + } + + err = perf_pmu_register(&ccn->dt.pmu, name, -1); + if (err) + goto error_pmu_register; + + return 0; + +error_pmu_register: +error_set_affinity: + unregister_cpu_notifier(&ccn->dt.cpu_nb); +error_cpu_notifier: + ida_simple_remove(&arm_ccn_pmu_ida, ccn->dt.id); + for (i = 0; i < ccn->num_xps; i++) + writel(0, ccn->xp[i].base + CCN_XP_DT_CONTROL); + writel(0, ccn->dt.base + CCN_DT_PMCR); + return err; } static void arm_ccn_pmu_cleanup(struct arm_ccn *ccn) { int i; + irq_set_affinity(ccn->irq, cpu_possible_mask); + unregister_cpu_notifier(&ccn->dt.cpu_nb); for (i = 0; i < ccn->num_xps; i++) writel(0, ccn->xp[i].base + CCN_XP_DT_CONTROL); writel(0, ccn->dt.base + CCN_DT_PMCR); @@ -1285,6 +1443,7 @@ static int arm_ccn_probe(struct platform_device *pdev) { struct arm_ccn *ccn; struct resource *res; + unsigned int irq; int err; ccn = devm_kzalloc(&pdev->dev, sizeof(*ccn), GFP_KERNEL); @@ -1309,6 +1468,7 @@ static int arm_ccn_probe(struct platform_device *pdev) res = platform_get_resource(pdev, IORESOURCE_IRQ, 0); if (!res) return -EINVAL; + irq = res->start; /* Check if we can use the interrupt */ writel(CCN_MN_ERRINT_STATUS__PMU_EVENTS__DISABLE, @@ -1318,13 +1478,12 @@ static int arm_ccn_probe(struct platform_device *pdev) /* Can set 'disable' bits, so can acknowledge interrupts */ writel(CCN_MN_ERRINT_STATUS__PMU_EVENTS__ENABLE, ccn->base + CCN_MN_ERRINT_STATUS); - err = devm_request_irq(ccn->dev, res->start, - arm_ccn_irq_handler, 0, dev_name(ccn->dev), - ccn); + err = devm_request_irq(ccn->dev, irq, arm_ccn_irq_handler, 0, + dev_name(ccn->dev), ccn); if (err) return err; - ccn->irq_used = 1; + ccn->irq = irq; } |