On Thu, 16 Jan 2025 04:59:11 +0000
Yoshihiro Furudera [off-list ref] wrote:

This adds a new dynamic PMU to the Perf Events framework to program and
control the Uncore PCI PMUs in Fujitsu chips.

This driver was created with reference to drivers/perf/qcom_l3_pmu.c.

This driver exports formatting and event information to sysfs so it can
be used by the perf user space tools with the syntaxes:

perf stat -e pci_iod0_pci0/ea-pci/ ls
perf stat -e pci_iod0_pci0/event=0x80/ ls

FUJITSU-MONAKA Specification URL:
https://github.com/fujitsu/FUJITSU-MONAKA

Signed-off-by: Yoshihiro Furudera <redacted>

Hi,

As you can probably guess, similar comments in here.
Assuming those little things tidied up feel free to add
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
to your v5.

mod_devicetable.h probably should be here.

+#include <linux/perf_event.h>
+#include <linux/platform_device.h>
+
+/* Number of counters on each PMU */
+#define PCI_NUM_COUNTERS  8
+/* Mask for the event type field within perf_event_attr.config and EVTYPE reg */
+#define PCI_EVTYPE_MASK   0xFF
+
+/* Perfmon registers */
+#define PCI_PM_EVCNTR(__cntr) (0x000 + __cntr * 8)
+#define PCI_PM_CNTCTL(__cntr) (0x100 + __cntr * 8)
+#define PCI_PM_EVTYPE(__cntr) (0x200 + __cntr * 8)

(__cntr)

+/*
+ * We must NOT create groups containing events from multiple hardware PMUs,
+ * although mixing different software and hardware PMUs is allowed.
+ */
+static bool fujitsu_pci__validate_event_group(struct perf_event *event)
+{
+	struct perf_event *leader = event->group_leader;
+	struct perf_event *sibling;
+	int counters = 0;
+
+	if (leader->pmu != event->pmu && !is_software_event(leader))
+		return false;
+
+	/* The sum of the counters used by the event and its leader event */
+	counters = 2;
+
+	for_each_sibling_event(sibling, leader) {
+		if (is_software_event(sibling))
+			continue;
+		if (sibling->pmu != event->pmu)
+			return false;
+		counters += 1;

counters++;

+	}
+
+	/*
+	 * If the group requires more counters than the HW has, it
+	 * cannot ever be scheduled.
+	 */
+	return counters <= PCI_NUM_COUNTERS;
+}

+
+static const struct attribute_group fujitsu_pci_pmu_events_group = {
+	.name = "events",
+	.attrs = fujitsu_pci_pmu_events

As below

+};
+
+static ssize_t cpumask_show(struct device *dev,
+			    struct device_attribute *attr, char *buf)
+{
+	struct pci_pmu *pcipmu = to_pci_pmu(dev_get_drvdata(dev));
+
+	return cpumap_print_to_pagebuf(true, buf, &pcipmu->cpumask);
+}
+
+static DEVICE_ATTR_RO(cpumask);
+
+static struct attribute *fujitsu_pci_pmu_cpumask_attrs[] = {
+	&dev_attr_cpumask.attr,
+	NULL
+};
+
+static const struct attribute_group fujitsu_pci_pmu_cpumask_attr_group = {
+	.attrs = fujitsu_pci_pmu_cpumask_attrs

Another trailing comma missing here.

+static int fujitsu_pci_pmu_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct acpi_device *acpi_dev;
+	struct pci_pmu *pcipmu;
+	struct resource *memrc;
+	char *name;
+	int ret;
+	u64 uid;
+
+	acpi_dev = ACPI_COMPANION(dev);
+	if (!acpi_dev)
+		return -ENODEV;
+
+	ret = acpi_dev_uid_to_integer(acpi_dev, &uid);
+	if (ret)
+		return dev_err_probe(dev, ret, "unable to read ACPI uid\n");
+
+	pcipmu = devm_kzalloc(dev, sizeof(*pcipmu), GFP_KERNEL);
+	if (!pcipmu)
+		return -ENOMEM;
+
+	name = devm_kasprintf(dev, GFP_KERNEL, "pci_iod%llu_pci%llu",
+			  (uid >> 4) & 0xF, uid & 0xF);
+	if (!name)
+		return -ENOMEM;
+
+	pcipmu->pmu = (struct pmu) {
+		.parent		= dev,
+		.task_ctx_nr	= perf_invalid_context,
+
+		.pmu_enable	= fujitsu_pci__pmu_enable,
+		.pmu_disable	= fujitsu_pci__pmu_disable,
+		.event_init	= fujitsu_pci__event_init,
+		.add		= fujitsu_pci__event_add,
+		.del		= fujitsu_pci__event_del,
+		.start		= fujitsu_pci__event_start,
+		.stop		= fujitsu_pci__event_stop,
+		.read		= fujitsu_pci__event_read,
+
+		.attr_groups	= fujitsu_pci_pmu_attr_grps,
+		.capabilities	= PERF_PMU_CAP_NO_EXCLUDE

As in previous.  Add trailing commas to all structure field fills that
aren't terminating NULL type entries.

+	};
+
+	pcipmu->regs = devm_platform_get_and_ioremap_resource(pdev, 0, &memrc);
+	if (IS_ERR(pcipmu->regs))
+		return PTR_ERR(pcipmu->regs);
+
+	fujitsu_pci__init(pcipmu);
+
+	ret = platform_get_irq(pdev, 0);
+	if (ret <= 0)
+		return ret;
+
+	ret = devm_request_irq(dev, ret, fujitsu_pci__handle_irq, 0,
+			       name, pcipmu);
+	if (ret)
+		return dev_err_probe(dev, ret, "Request for IRQ failed for slice @%pa\n",
+						&memrc->start);
+
+	/* Add this instance to the list used by the offline callback */
+	ret = cpuhp_state_add_instance(pci_pmu_cpuhp_state, &pcipmu->node);
+	if (ret)
+		return dev_err_probe(dev, ret, "Error registering hotplug");
+
+	ret = perf_pmu_register(&pcipmu->pmu, name, -1);
+	if (ret < 0)
+		return dev_err_probe(dev, ret, "Failed to register PCI PMU\n");
+
+	dev_dbg(dev, "Registered %s, type: %d\n", name, pcipmu->pmu.type);
+
+	return 0;
+}