Register PMU device of PTT trace, then users can use trace through perf
command. The driver makes use of perf AUX trace and support following
events to configure the trace:
- filter: select Root port or Endpoint to trace
- type: select the type of traced TLP headers
- direction: select the direction of traced TLP headers
- format: select the data format of the traced TLP headers
This patch adds the PMU driver part of PTT trace. The perf command support
of PTT trace is added in the following patch.
Signed-off-by: Yicong Yang <[email protected]>
---
drivers/hwtracing/ptt/hisi_ptt.c | 540 +++++++++++++++++++++++++++++++
drivers/hwtracing/ptt/hisi_ptt.h | 22 ++
2 files changed, 562 insertions(+)
diff --git a/drivers/hwtracing/ptt/hisi_ptt.c b/drivers/hwtracing/ptt/hisi_ptt.c
index 935dc9b44a54..f06fbbb8a12a 100644
--- a/drivers/hwtracing/ptt/hisi_ptt.c
+++ b/drivers/hwtracing/ptt/hisi_ptt.c
@@ -17,6 +17,7 @@
#include <linux/iopoll.h>
#include <linux/module.h>
#include <linux/sysfs.h>
+#include <linux/vmalloc.h>
#include "hisi_ptt.h"
@@ -161,6 +162,114 @@ static int hisi_ptt_trace_start(struct hisi_ptt *hisi_ptt)
return 0;
}
+static int hisi_ptt_update_aux(struct hisi_ptt *hisi_ptt, int index, bool stop)
+{
+ struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
+ struct perf_output_handle *handle = &ctrl->handle;
+ struct perf_event *event = handle->event;
+ struct hisi_ptt_pmu_buf *buf;
+ void *addr;
+
+ buf = perf_get_aux(handle);
+ if (!buf || !handle->size)
+ return -EINVAL;
+
+ addr = ctrl->trace_buf[ctrl->buf_index].addr;
+
+ memcpy(buf->base + buf->pos, addr, HISI_PTT_TRACE_BUF_SIZE);
+ memset(addr, 0, HISI_PTT_TRACE_BUF_SIZE);
+ buf->pos += HISI_PTT_TRACE_BUF_SIZE;
+
+ if (stop) {
+ perf_aux_output_end(handle, buf->pos);
+ } else if (buf->length - buf->pos < HISI_PTT_TRACE_BUF_SIZE) {
+ perf_aux_output_skip(handle, buf->length - buf->pos);
+ perf_aux_output_end(handle, buf->pos);
+
+ buf = perf_aux_output_begin(handle, event);
+ if (!buf)
+ return -EINVAL;
+
+ buf->pos = handle->head % buf->length;
+ if (buf->length - buf->pos < HISI_PTT_TRACE_BUF_SIZE) {
+ perf_aux_output_end(handle, 0);
+ return -EINVAL;
+ }
+ }
+
+ return 0;
+}
+
+static irqreturn_t hisi_ptt_isr(int irq, void *context)
+{
+ struct hisi_ptt *hisi_ptt = context;
+ u32 status, buf_idx;
+
+ status = readl(hisi_ptt->iobase + HISI_PTT_TRACE_INT_STAT);
+ buf_idx = ffs(status) - 1;
+
+ /* Clear the interrupt status of buffer @buf_idx */
+ writel(status, hisi_ptt->iobase + HISI_PTT_TRACE_INT_STAT);
+
+ /*
+ * Update the AUX buffer and cache the current buffer index,
+ * as we need to know this and save the data when the trace
+ * is ended out of the interrupt handler. End the trace
+ * if the updating fails.
+ */
+ if (hisi_ptt_update_aux(hisi_ptt, buf_idx, false))
+ hisi_ptt_trace_end(hisi_ptt);
+ else
+ hisi_ptt->trace_ctrl.buf_index = (buf_idx + 1) % HISI_PTT_TRACE_BUF_CNT;
+
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t hisi_ptt_irq(int irq, void *context)
+{
+ struct hisi_ptt *hisi_ptt = context;
+ u32 status;
+
+ status = readl(hisi_ptt->iobase + HISI_PTT_TRACE_INT_STAT);
+ if (!(status & HISI_PTT_TRACE_INT_STAT_MASK))
+ return IRQ_NONE;
+
+ return IRQ_WAKE_THREAD;
+}
+
+static void hisi_ptt_irq_free_vectors(void *pdev)
+{
+ pci_free_irq_vectors(pdev);
+}
+
+static int hisi_ptt_register_irq(struct hisi_ptt *hisi_ptt)
+{
+ struct pci_dev *pdev = hisi_ptt->pdev;
+ int ret;
+
+ ret = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_MSI);
+ if (ret < 0) {
+ pci_err(pdev, "failed to allocate irq vector, ret = %d.\n", ret);
+ return ret;
+ }
+
+ ret = devm_add_action_or_reset(&pdev->dev, hisi_ptt_irq_free_vectors, pdev);
+ if (ret < 0)
+ return ret;
+
+ ret = devm_request_threaded_irq(&pdev->dev,
+ pci_irq_vector(pdev, HISI_PTT_TRACE_DMA_IRQ),
+ hisi_ptt_irq, hisi_ptt_isr, 0,
+ DRV_NAME, hisi_ptt);
+ if (ret) {
+ pci_err(pdev, "failed to request irq %d, ret = %d.\n",
+ pci_irq_vector(pdev, HISI_PTT_TRACE_DMA_IRQ), ret);
+ return ret;
+ }
+
+ return 0;
+}
+
static int hisi_ptt_init_filters(struct pci_dev *pdev, void *data)
{
struct hisi_ptt_filter_desc *filter;
@@ -241,6 +350,419 @@ static int hisi_ptt_init_ctrls(struct hisi_ptt *hisi_ptt)
return 0;
}
+#define HISI_PTT_PMU_FILTER_IS_PORT BIT(19)
+#define HISI_PTT_PMU_FILTER_VAL_MASK GENMASK(15, 0)
+#define HISI_PTT_PMU_DIRECTION_MASK GENMASK(23, 20)
+#define HISI_PTT_PMU_TYPE_MASK GENMASK(31, 24)
+#define HISI_PTT_PMU_FORMAT_MASK GENMASK(35, 32)
+
+static ssize_t available_root_port_filters_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct hisi_ptt *hisi_ptt = to_hisi_ptt(dev_get_drvdata(dev));
+ struct hisi_ptt_filter_desc *filter;
+ int pos = 0;
+
+ mutex_lock(&hisi_ptt->mutex);
+ if (list_empty(&hisi_ptt->port_filters)) {
+ pos = sysfs_emit(buf, "\n");
+ goto out;
+ }
+
+ list_for_each_entry(filter, &hisi_ptt->port_filters, list)
+ pos += sysfs_emit_at(buf, pos, "%s 0x%05lx\n",
+ pci_name(filter->pdev),
+ hisi_ptt_get_filter_val(filter->pdev) |
+ HISI_PTT_PMU_FILTER_IS_PORT);
+
+out:
+ mutex_unlock(&hisi_ptt->mutex);
+ return pos;
+}
+static DEVICE_ATTR_ADMIN_RO(available_root_port_filters);
+
+static ssize_t available_requester_filters_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct hisi_ptt *hisi_ptt = to_hisi_ptt(dev_get_drvdata(dev));
+ struct hisi_ptt_filter_desc *filter;
+ int pos = 0;
+
+ mutex_lock(&hisi_ptt->mutex);
+ if (list_empty(&hisi_ptt->req_filters)) {
+ pos = sysfs_emit(buf, "\n");
+ goto out;
+ }
+
+ list_for_each_entry(filter, &hisi_ptt->req_filters, list)
+ pos += sysfs_emit_at(buf, pos, "%s 0x%05x\n",
+ pci_name(filter->pdev),
+ hisi_ptt_get_filter_val(filter->pdev));
+
+out:
+ mutex_unlock(&hisi_ptt->mutex);
+ return pos;
+}
+static DEVICE_ATTR_ADMIN_RO(available_requester_filters);
+
+PMU_FORMAT_ATTR(filter, "config:0-19");
+PMU_FORMAT_ATTR(direction, "config:20-23");
+PMU_FORMAT_ATTR(type, "config:24-31");
+PMU_FORMAT_ATTR(format, "config:32-35");
+
+static struct attribute *hisi_ptt_pmu_format_attrs[] = {
+ &format_attr_filter.attr,
+ &format_attr_direction.attr,
+ &format_attr_type.attr,
+ &format_attr_format.attr,
+ NULL
+};
+
+static struct attribute_group hisi_ptt_pmu_format_group = {
+ .name = "format",
+ .attrs = hisi_ptt_pmu_format_attrs,
+};
+
+static struct attribute *hisi_ptt_pmu_filter_attrs[] = {
+ &dev_attr_available_root_port_filters.attr,
+ &dev_attr_available_requester_filters.attr,
+ NULL
+};
+
+static struct attribute_group hisi_ptt_pmu_filter_group = {
+ .attrs = hisi_ptt_pmu_filter_attrs,
+};
+
+static const struct attribute_group *hisi_ptt_pmu_groups[] = {
+ &hisi_ptt_pmu_format_group,
+ &hisi_ptt_pmu_filter_group,
+ NULL
+};
+
+/*
+ * Check whether the config is valid or not. Some configs are multi-selectable
+ * and can be set simultaneously, while some are single selectable (onehot).
+ * Use this function to check the non-onehot configs while
+ * hisi_ptt_trace_valid_config_onehot() for the onehot ones.
+ */
+static int hisi_ptt_trace_valid_config(u32 val, const u32 *available_list, u32 list_size)
+{
+ int i;
+
+ /* The non-onehot configs cannot be 0. */
+ if (!val)
+ return -EINVAL;
+
+ /*
+ * Walk the available list and clear the valid bits of
+ * the config. If there is any resident bit after the
+ * walk then the config is invalid.
+ */
+ for (i = 0; i < list_size; i++)
+ val &= ~available_list[i];
+
+ return val ? -EINVAL : 0;
+}
+
+static int hisi_ptt_trace_valid_config_onehot(u32 val, const u32 *available_list, u32 list_size)
+{
+ int i;
+
+ for (i = 0; i < list_size; i++)
+ if (val == available_list[i])
+ return 0;
+
+ return -EINVAL;
+}
+
+static int hisi_ptt_trace_init_filter(struct hisi_ptt *hisi_ptt, u64 config)
+{
+ unsigned long val, port_mask = hisi_ptt->port_mask;
+ struct hisi_ptt_filter_desc *filter;
+ int ret = -EINVAL;
+
+ hisi_ptt->trace_ctrl.is_port = FIELD_GET(HISI_PTT_PMU_FILTER_IS_PORT, config);
+ val = FIELD_GET(HISI_PTT_PMU_FILTER_VAL_MASK, config);
+
+ /*
+ * Port filters are defined as bit mask. For port filters, check
+ * the bits in the @val are within the range of hisi_ptt->port_mask
+ * and whether it's empty or not, otherwise user has specified
+ * some unsupported root ports.
+ *
+ * For Requester ID filters, walk the available filter list to see
+ * whether we have one matched.
+ */
+ if (!hisi_ptt->trace_ctrl.is_port) {
+ list_for_each_entry(filter, &hisi_ptt->req_filters, list)
+ if (val == hisi_ptt_get_filter_val(filter->pdev)) {
+ ret = 0;
+ break;
+ }
+ } else if (bitmap_subset(&val, &port_mask, BITS_PER_LONG)) {
+ ret = 0;
+ }
+
+ if (ret)
+ return ret;
+
+ hisi_ptt->trace_ctrl.filter = val;
+ return 0;
+}
+
+static int hisi_ptt_pmu_event_init(struct perf_event *event)
+{
+ /*
+ * The supported value of the direction parameter. See hisi_ptt.rst
+ * documentation for more details.
+ */
+ static const u32 hisi_ptt_trace_available_direction[] = {
+ 0,
+ 1,
+ 2,
+ 3,
+ };
+ /* Different types can be set simultaneously */
+ static const u32 hisi_ptt_trace_available_type[] = {
+ 1, /* posted_request */
+ 2, /* non-posted_request */
+ 4, /* completion */
+ };
+ static const u32 hisi_ptt_trace_availble_format[] = {
+ 0, /* 4DW */
+ 1, /* 8DW */
+ };
+ struct hisi_ptt *hisi_ptt = to_hisi_ptt(event->pmu);
+ struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
+ int ret;
+ u32 val;
+
+ if (event->attr.type != hisi_ptt->hisi_ptt_pmu.type)
+ return -ENOENT;
+
+ mutex_lock(&hisi_ptt->mutex);
+
+ ret = hisi_ptt_trace_init_filter(hisi_ptt, event->attr.config);
+ if (ret < 0)
+ goto out;
+
+ val = FIELD_GET(HISI_PTT_PMU_DIRECTION_MASK, event->attr.config);
+ ret = hisi_ptt_trace_valid_config_onehot(val, hisi_ptt_trace_available_direction,
+ ARRAY_SIZE(hisi_ptt_trace_available_direction));
+ if (ret < 0)
+ goto out;
+ ctrl->direction = val;
+
+ val = FIELD_GET(HISI_PTT_PMU_TYPE_MASK, event->attr.config);
+ ret = hisi_ptt_trace_valid_config(val, hisi_ptt_trace_available_type,
+ ARRAY_SIZE(hisi_ptt_trace_available_type));
+ if (ret < 0)
+ goto out;
+ ctrl->type = val;
+
+ val = FIELD_GET(HISI_PTT_PMU_FORMAT_MASK, event->attr.config);
+ ret = hisi_ptt_trace_valid_config_onehot(val, hisi_ptt_trace_availble_format,
+ ARRAY_SIZE(hisi_ptt_trace_availble_format));
+ if (ret < 0)
+ goto out;
+ ctrl->format = val;
+
+out:
+ mutex_unlock(&hisi_ptt->mutex);
+ return ret;
+}
+
+static void *hisi_ptt_pmu_setup_aux(struct perf_event *event, void **pages,
+ int nr_pages, bool overwrite)
+{
+ struct hisi_ptt_pmu_buf *buf;
+ struct page **pagelist;
+ int i;
+
+ if (overwrite) {
+ dev_warn(event->pmu->dev, "Overwrite mode is not supported\n");
+ return NULL;
+ }
+
+ /* If the pages size less than buffers, we cannot start trace */
+ if (nr_pages < HISI_PTT_TRACE_TOTAL_BUF_SIZE / PAGE_SIZE)
+ return NULL;
+
+ buf = kzalloc(sizeof(*buf), GFP_KERNEL);
+ if (!buf)
+ return NULL;
+
+ pagelist = kcalloc(nr_pages, sizeof(*pagelist), GFP_KERNEL);
+ if (!pagelist) {
+ kfree(buf);
+ return NULL;
+ }
+
+ for (i = 0; i < nr_pages; i++)
+ pagelist[i] = virt_to_page(pages[i]);
+
+ buf->base = vmap(pagelist, nr_pages, VM_MAP, PAGE_KERNEL);
+ if (!buf->base) {
+ kfree(pagelist);
+ kfree(buf);
+ return NULL;
+ }
+
+ buf->nr_pages = nr_pages;
+ buf->length = nr_pages * PAGE_SIZE;
+ buf->pos = 0;
+
+ kfree(pagelist);
+ return buf;
+}
+
+static void hisi_ptt_pmu_free_aux(void *aux)
+{
+ struct hisi_ptt_pmu_buf *buf = aux;
+
+ vunmap(buf->base);
+ kfree(buf);
+}
+
+static void hisi_ptt_pmu_start(struct perf_event *event, int flags)
+{
+ struct hisi_ptt *hisi_ptt = to_hisi_ptt(event->pmu);
+ struct perf_output_handle *handle = &hisi_ptt->trace_ctrl.handle;
+ struct hw_perf_event *hwc = &event->hw;
+ struct hisi_ptt_pmu_buf *buf;
+ int cpu = event->cpu;
+ int ret;
+
+ hwc->state = 0;
+ mutex_lock(&hisi_ptt->mutex);
+ if (hisi_ptt->trace_ctrl.started) {
+ pci_dbg(hisi_ptt->pdev, "trace has already started\n");
+ goto stop;
+ }
+
+ if (cpu == -1)
+ cpu = hisi_ptt->trace_ctrl.default_cpu;
+
+ /*
+ * Handle the interrupt on the same cpu which starts the trace to avoid
+ * context mismatch. Otherwise we'll trigger the WARN from the perf
+ * core in event_function_local().
+ */
+ WARN_ON(irq_set_affinity(pci_irq_vector(hisi_ptt->pdev, HISI_PTT_TRACE_DMA_IRQ),
+ cpumask_of(cpu)));
+
+ ret = hisi_ptt_alloc_trace_buf(hisi_ptt);
+ if (ret) {
+ pci_dbg(hisi_ptt->pdev, "alloc trace buf failed, ret = %d\n", ret);
+ goto stop;
+ }
+
+ buf = perf_aux_output_begin(handle, event);
+ if (!buf) {
+ pci_dbg(hisi_ptt->pdev, "aux output begin failed\n");
+ goto stop;
+ }
+
+ buf->pos = handle->head % buf->length;
+
+ ret = hisi_ptt_trace_start(hisi_ptt);
+ if (ret) {
+ pci_dbg(hisi_ptt->pdev, "trace start failed, ret = %d\n", ret);
+ perf_aux_output_end(handle, 0);
+ goto stop;
+ }
+
+ mutex_unlock(&hisi_ptt->mutex);
+ return;
+stop:
+ event->hw.state |= PERF_HES_STOPPED;
+ mutex_unlock(&hisi_ptt->mutex);
+}
+
+static void hisi_ptt_pmu_stop(struct perf_event *event, int flags)
+{
+ struct hisi_ptt *hisi_ptt = to_hisi_ptt(event->pmu);
+ struct hw_perf_event *hwc = &event->hw;
+
+ if (hwc->state & PERF_HES_STOPPED)
+ return;
+
+ mutex_lock(&hisi_ptt->mutex);
+ if (hisi_ptt->trace_ctrl.started) {
+ hisi_ptt_trace_end(hisi_ptt);
+ WARN(!hisi_ptt_wait_trace_hw_idle(hisi_ptt), "Device is still busy");
+ hisi_ptt_update_aux(hisi_ptt, hisi_ptt->trace_ctrl.buf_index, true);
+ }
+ mutex_unlock(&hisi_ptt->mutex);
+
+ hwc->state |= PERF_HES_STOPPED;
+ perf_event_update_userpage(event);
+ hwc->state |= PERF_HES_UPTODATE;
+}
+
+static int hisi_ptt_pmu_add(struct perf_event *event, int flags)
+{
+ struct hisi_ptt *hisi_ptt = to_hisi_ptt(event->pmu);
+ struct hw_perf_event *hwc = &event->hw;
+ int cpu = event->cpu;
+
+ /*
+ * Only allow the default cpu to add the event if user doesn't specify
+ * the cpus.
+ */
+ if (cpu == -1 && smp_processor_id() != hisi_ptt->trace_ctrl.default_cpu)
+ return 0;
+
+ hwc->state = PERF_HES_STOPPED | PERF_HES_UPTODATE;
+
+ if (flags & PERF_EF_START) {
+ hisi_ptt_pmu_start(event, PERF_EF_RELOAD);
+ if (hwc->state & PERF_HES_STOPPED)
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static void hisi_ptt_pmu_del(struct perf_event *event, int flags)
+{
+ hisi_ptt_pmu_stop(event, PERF_EF_UPDATE);
+}
+
+static int hisi_ptt_register_pmu(struct hisi_ptt *hisi_ptt)
+{
+ u16 core_id, sicl_id;
+ char *pmu_name;
+ u32 reg;
+
+ hisi_ptt->hisi_ptt_pmu = (struct pmu) {
+ .module = THIS_MODULE,
+ .capabilities = PERF_PMU_CAP_EXCLUSIVE | PERF_PMU_CAP_ITRACE,
+ .task_ctx_nr = perf_sw_context,
+ .attr_groups = hisi_ptt_pmu_groups,
+ .event_init = hisi_ptt_pmu_event_init,
+ .setup_aux = hisi_ptt_pmu_setup_aux,
+ .free_aux = hisi_ptt_pmu_free_aux,
+ .start = hisi_ptt_pmu_start,
+ .stop = hisi_ptt_pmu_stop,
+ .add = hisi_ptt_pmu_add,
+ .del = hisi_ptt_pmu_del,
+ };
+
+ reg = readl(hisi_ptt->iobase + HISI_PTT_LOCATION);
+ core_id = FIELD_GET(HISI_PTT_CORE_ID, reg);
+ sicl_id = FIELD_GET(HISI_PTT_SICL_ID, reg);
+
+ pmu_name = devm_kasprintf(&hisi_ptt->pdev->dev, GFP_KERNEL, "hisi_ptt%u_%u",
+ sicl_id, core_id);
+ if (!pmu_name)
+ return -ENOMEM;
+
+ return perf_pmu_register(&hisi_ptt->hisi_ptt_pmu, pmu_name, -1);
+}
+
/*
* The DMA of PTT trace can only use direct mapping, due to some
* hardware restriction. Check whether there is an IOMMU or the
@@ -303,15 +825,32 @@ static int hisi_ptt_probe(struct pci_dev *pdev,
pci_set_master(pdev);
+ ret = hisi_ptt_register_irq(hisi_ptt);
+ if (ret)
+ return ret;
+
ret = hisi_ptt_init_ctrls(hisi_ptt);
if (ret) {
pci_err(pdev, "failed to init controls, ret = %d.\n", ret);
return ret;
}
+ ret = hisi_ptt_register_pmu(hisi_ptt);
+ if (ret) {
+ pci_err(pdev, "failed to register pmu device, ret = %d", ret);
+ return ret;
+ }
+
return 0;
}
+void hisi_ptt_remove(struct pci_dev *pdev)
+{
+ struct hisi_ptt *hisi_ptt = pci_get_drvdata(pdev);
+
+ perf_pmu_unregister(&hisi_ptt->hisi_ptt_pmu);
+}
+
static const struct pci_device_id hisi_ptt_id_tbl[] = {
{ PCI_DEVICE(PCI_VENDOR_ID_HUAWEI, 0xa12e) },
{ }
@@ -322,6 +861,7 @@ static struct pci_driver hisi_ptt_driver = {
.name = DRV_NAME,
.id_table = hisi_ptt_id_tbl,
.probe = hisi_ptt_probe,
+ .remove = hisi_ptt_remove,
};
module_pci_driver(hisi_ptt_driver);
diff --git a/drivers/hwtracing/ptt/hisi_ptt.h b/drivers/hwtracing/ptt/hisi_ptt.h
index 9a253b93e750..29b6d6293d6c 100644
--- a/drivers/hwtracing/ptt/hisi_ptt.h
+++ b/drivers/hwtracing/ptt/hisi_ptt.h
@@ -13,6 +13,7 @@
#include <linux/list.h>
#include <linux/mutex.h>
#include <linux/pci.h>
+#include <linux/perf_event.h>
#include <linux/types.h>
#define DRV_NAME "hisi_ptt"
@@ -78,6 +79,7 @@ struct hisi_ptt_dma_buffer {
* struct hisi_ptt_trace_ctrl - control and status of PTT trace
* @trace_buf: array of the trace buffers for holding the trace data.
* the length will be HISI_PTT_TRACE_BUF_CNT.
+ * @handle: perf output handle of current trace session
* @default_cpu: default cpu to start the trace session
* @buf_index: the index of current using trace buffer
* @started: current trace status, true for started
@@ -89,6 +91,7 @@ struct hisi_ptt_dma_buffer {
*/
struct hisi_ptt_trace_ctrl {
struct hisi_ptt_dma_buffer *trace_buf;
+ struct perf_output_handle handle;
int default_cpu;
u32 buf_index;
bool started;
@@ -109,9 +112,25 @@ struct hisi_ptt_filter_desc {
struct pci_dev *pdev;
};
+
+/**
+ * struct hisi_ptt_pmu_buf - descriptor of the AUX buffer of PTT trace
+ * @length: size of the AUX buffer
+ * @nr_pages: number of pages of the AUX buffer
+ * @base: start address of AUX buffer
+ * @pos: position in the AUX buffer to commit traced data
+ */
+struct hisi_ptt_pmu_buf {
+ size_t length;
+ int nr_pages;
+ void *base;
+ long pos;
+};
+
/**
* struct hisi_ptt - per PTT device data
* @trace_ctrl: the control information of PTT trace
+ * @hisi_ptt_pmu: the pum device of trace
* @iobase: base IO address of the device
* @pdev: pci_dev of this PTT device
* @mutex: mutex to protect the filter list and serialize the perf process.
@@ -123,6 +142,7 @@ struct hisi_ptt_filter_desc {
*/
struct hisi_ptt {
struct hisi_ptt_trace_ctrl trace_ctrl;
+ struct pmu hisi_ptt_pmu;
void __iomem *iobase;
struct pci_dev *pdev;
struct mutex mutex;
@@ -141,4 +161,6 @@ struct hisi_ptt {
u16 port_mask;
};
+#define to_hisi_ptt(pmu) container_of(pmu, struct hisi_ptt, hisi_ptt_pmu)
+
#endif /* _HISI_PTT_H */
--
2.24.0
On 2022/3/8 18:21, Jonathan Cameron wrote:
> On Tue, 8 Mar 2022 16:49:25 +0800
> Yicong Yang <[email protected]> wrote:
>
>> Register PMU device of PTT trace, then users can use trace through perf
>> command. The driver makes use of perf AUX trace and support following
>> events to configure the trace:
>>
>> - filter: select Root port or Endpoint to trace
>> - type: select the type of traced TLP headers
>> - direction: select the direction of traced TLP headers
>> - format: select the data format of the traced TLP headers
>>
>> This patch adds the PMU driver part of PTT trace. The perf command support
>> of PTT trace is added in the following patch.
>>
>> Signed-off-by: Yicong Yang <[email protected]>
>
> It seems to me that you ended up doing both suggestions for
> how to clean up the remove order when it was meant to be
> a question of picking one or the other.
>
> Otherwise this looks good to me - so with that tidied up
>
Hi Jonathan,
Thanks for the comments. I'd like to illustrate the reason why I decide to
manually unregister the PMU device.
The DMA buffers are devm allocated when necessary. They're only allocated
when user is going to use the PTT in the first time after the driver's probe,
so when driver removal the buffers are released prior to the PMU device's
unregistration. I think there's a race condition.
IIUC, The PMU device(as the user interface) should be unregistered first then
we're safe to free the DMA buffers. But unregister the PMU device by devm
cannot keep that order.
Thanks,
Yicong
> Reviewed-by: Jonathan Cameron <[email protected]>
>
>> ---
>
>> +
>> +static int hisi_ptt_register_pmu(struct hisi_ptt *hisi_ptt)
>> +{
>> + u16 core_id, sicl_id;
>> + char *pmu_name;
>> + u32 reg;
>> +
>> + hisi_ptt->hisi_ptt_pmu = (struct pmu) {
>> + .module = THIS_MODULE,
>> + .capabilities = PERF_PMU_CAP_EXCLUSIVE | PERF_PMU_CAP_ITRACE,
>> + .task_ctx_nr = perf_sw_context,
>> + .attr_groups = hisi_ptt_pmu_groups,
>> + .event_init = hisi_ptt_pmu_event_init,
>> + .setup_aux = hisi_ptt_pmu_setup_aux,
>> + .free_aux = hisi_ptt_pmu_free_aux,
>> + .start = hisi_ptt_pmu_start,
>> + .stop = hisi_ptt_pmu_stop,
>> + .add = hisi_ptt_pmu_add,
>> + .del = hisi_ptt_pmu_del,
>> + };
>> +
>> + reg = readl(hisi_ptt->iobase + HISI_PTT_LOCATION);
>> + core_id = FIELD_GET(HISI_PTT_CORE_ID, reg);
>> + sicl_id = FIELD_GET(HISI_PTT_SICL_ID, reg);
>> +
>> + pmu_name = devm_kasprintf(&hisi_ptt->pdev->dev, GFP_KERNEL, "hisi_ptt%u_%u",
>> + sicl_id, core_id);
>> + if (!pmu_name)
>> + return -ENOMEM;
>> +
>> + return perf_pmu_register(&hisi_ptt->hisi_ptt_pmu, pmu_name, -1);
>
> As below, you can put back the devm cleanup that you had in v4 now you
> have modified how the filter cleanup is done to also be devm managed.
>
>> +}
>> +
>> /*
>> * The DMA of PTT trace can only use direct mapping, due to some
>> * hardware restriction. Check whether there is an IOMMU or the
>> @@ -303,15 +825,32 @@ static int hisi_ptt_probe(struct pci_dev *pdev,
>>
>> pci_set_master(pdev);
>>
>> + ret = hisi_ptt_register_irq(hisi_ptt);
>> + if (ret)
>> + return ret;
>> +
>> ret = hisi_ptt_init_ctrls(hisi_ptt);
>> if (ret) {
>> pci_err(pdev, "failed to init controls, ret = %d.\n", ret);
>> return ret;
>> }
>>
>> + ret = hisi_ptt_register_pmu(hisi_ptt);
>> + if (ret) {
>> + pci_err(pdev, "failed to register pmu device, ret = %d", ret);
>> + return ret;
>> + }
>> +
>> return 0;
>> }
>>
>> +void hisi_ptt_remove(struct pci_dev *pdev)
>> +{
>> + struct hisi_ptt *hisi_ptt = pci_get_drvdata(pdev);
>> +
>> + perf_pmu_unregister(&hisi_ptt->hisi_ptt_pmu);
>
> Now you have the filter cleanup occurring using a devm_add_action_or_reset()
> there is no need to have a manual cleanup of this - you can
> use the approach of a devm_add_action_or_reset like you had in v4.
>
> As it is the last call in the probe() order it will be the first one
> called in the device managed cleanup.
>
>> +}
>> +
>
>
> .
>
On 2022/3/8 20:06, Jonathan Cameron wrote:
> On Tue, 8 Mar 2022 19:13:08 +0800
> Yicong Yang <[email protected]> wrote:
>
>> On 2022/3/8 18:21, Jonathan Cameron wrote:
>>> On Tue, 8 Mar 2022 16:49:25 +0800
>>> Yicong Yang <[email protected]> wrote:
>>>
>>>> Register PMU device of PTT trace, then users can use trace through perf
>>>> command. The driver makes use of perf AUX trace and support following
>>>> events to configure the trace:
>>>>
>>>> - filter: select Root port or Endpoint to trace
>>>> - type: select the type of traced TLP headers
>>>> - direction: select the direction of traced TLP headers
>>>> - format: select the data format of the traced TLP headers
>>>>
>>>> This patch adds the PMU driver part of PTT trace. The perf command support
>>>> of PTT trace is added in the following patch.
>>>>
>>>> Signed-off-by: Yicong Yang <[email protected]>
>>>
>>> It seems to me that you ended up doing both suggestions for
>>> how to clean up the remove order when it was meant to be
>>> a question of picking one or the other.
>>>
>>> Otherwise this looks good to me - so with that tidied up
>>>
>>
>> Hi Jonathan,
>>
>> Thanks for the comments. I'd like to illustrate the reason why I decide to
>> manually unregister the PMU device.
>>
>> The DMA buffers are devm allocated when necessary. They're only allocated
>> when user is going to use the PTT in the first time after the driver's probe,
>> so when driver removal the buffers are released prior to the PMU device's
>> unregistration. I think there's a race condition.
>>
>> IIUC, The PMU device(as the user interface) should be unregistered first then
>> we're safe to free the DMA buffers. But unregister the PMU device by devm
>> cannot keep that order.
>
> Ok. Please add a comment in the remove() giving this reasoning.
>
Sure will add a comment for the reason why we need this manual unregistration in remove().
> Jonathan
>
>>
>> Thanks,
>> Yicong
>>
>>> Reviewed-by: Jonathan Cameron <[email protected]>
>>>
>>>> ---
>>>
>>>> +
>>>> +static int hisi_ptt_register_pmu(struct hisi_ptt *hisi_ptt)
>>>> +{
>>>> + u16 core_id, sicl_id;
>>>> + char *pmu_name;
>>>> + u32 reg;
>>>> +
>>>> + hisi_ptt->hisi_ptt_pmu = (struct pmu) {
>>>> + .module = THIS_MODULE,
>>>> + .capabilities = PERF_PMU_CAP_EXCLUSIVE | PERF_PMU_CAP_ITRACE,
>>>> + .task_ctx_nr = perf_sw_context,
>>>> + .attr_groups = hisi_ptt_pmu_groups,
>>>> + .event_init = hisi_ptt_pmu_event_init,
>>>> + .setup_aux = hisi_ptt_pmu_setup_aux,
>>>> + .free_aux = hisi_ptt_pmu_free_aux,
>>>> + .start = hisi_ptt_pmu_start,
>>>> + .stop = hisi_ptt_pmu_stop,
>>>> + .add = hisi_ptt_pmu_add,
>>>> + .del = hisi_ptt_pmu_del,
>>>> + };
>>>> +
>>>> + reg = readl(hisi_ptt->iobase + HISI_PTT_LOCATION);
>>>> + core_id = FIELD_GET(HISI_PTT_CORE_ID, reg);
>>>> + sicl_id = FIELD_GET(HISI_PTT_SICL_ID, reg);
>>>> +
>>>> + pmu_name = devm_kasprintf(&hisi_ptt->pdev->dev, GFP_KERNEL, "hisi_ptt%u_%u",
>>>> + sicl_id, core_id);
>>>> + if (!pmu_name)
>>>> + return -ENOMEM;
>>>> +
>>>> + return perf_pmu_register(&hisi_ptt->hisi_ptt_pmu, pmu_name, -1);
>>>
>>> As below, you can put back the devm cleanup that you had in v4 now you
>>> have modified how the filter cleanup is done to also be devm managed.
>>>
>>>> +}
>>>> +
>>>> /*
>>>> * The DMA of PTT trace can only use direct mapping, due to some
>>>> * hardware restriction. Check whether there is an IOMMU or the
>>>> @@ -303,15 +825,32 @@ static int hisi_ptt_probe(struct pci_dev *pdev,
>>>>
>>>> pci_set_master(pdev);
>>>>
>>>> + ret = hisi_ptt_register_irq(hisi_ptt);
>>>> + if (ret)
>>>> + return ret;
>>>> +
>>>> ret = hisi_ptt_init_ctrls(hisi_ptt);
>>>> if (ret) {
>>>> pci_err(pdev, "failed to init controls, ret = %d.\n", ret);
>>>> return ret;
>>>> }
>>>>
>>>> + ret = hisi_ptt_register_pmu(hisi_ptt);
>>>> + if (ret) {
>>>> + pci_err(pdev, "failed to register pmu device, ret = %d", ret);
>>>> + return ret;
>>>> + }
>>>> +
>>>> return 0;
>>>> }
>>>>
>>>> +void hisi_ptt_remove(struct pci_dev *pdev)
>>>> +{
>>>> + struct hisi_ptt *hisi_ptt = pci_get_drvdata(pdev);
>>>> +
>>>> + perf_pmu_unregister(&hisi_ptt->hisi_ptt_pmu);
>>>
>>> Now you have the filter cleanup occurring using a devm_add_action_or_reset()
>>> there is no need to have a manual cleanup of this - you can
>>> use the approach of a devm_add_action_or_reset like you had in v4.
>>>
>>> As it is the last call in the probe() order it will be the first one
>>> called in the device managed cleanup.
>>>
>>>> +}
>>>> +
>>>
>>>
>>> .
>>>
>
> .
>
On Tue, 8 Mar 2022 19:13:08 +0800
Yicong Yang <[email protected]> wrote:
> On 2022/3/8 18:21, Jonathan Cameron wrote:
> > On Tue, 8 Mar 2022 16:49:25 +0800
> > Yicong Yang <[email protected]> wrote:
> >
> >> Register PMU device of PTT trace, then users can use trace through perf
> >> command. The driver makes use of perf AUX trace and support following
> >> events to configure the trace:
> >>
> >> - filter: select Root port or Endpoint to trace
> >> - type: select the type of traced TLP headers
> >> - direction: select the direction of traced TLP headers
> >> - format: select the data format of the traced TLP headers
> >>
> >> This patch adds the PMU driver part of PTT trace. The perf command support
> >> of PTT trace is added in the following patch.
> >>
> >> Signed-off-by: Yicong Yang <[email protected]>
> >
> > It seems to me that you ended up doing both suggestions for
> > how to clean up the remove order when it was meant to be
> > a question of picking one or the other.
> >
> > Otherwise this looks good to me - so with that tidied up
> >
>
> Hi Jonathan,
>
> Thanks for the comments. I'd like to illustrate the reason why I decide to
> manually unregister the PMU device.
>
> The DMA buffers are devm allocated when necessary. They're only allocated
> when user is going to use the PTT in the first time after the driver's probe,
> so when driver removal the buffers are released prior to the PMU device's
> unregistration. I think there's a race condition.
>
> IIUC, The PMU device(as the user interface) should be unregistered first then
> we're safe to free the DMA buffers. But unregister the PMU device by devm
> cannot keep that order.
Ok. Please add a comment in the remove() giving this reasoning.
Jonathan
>
> Thanks,
> Yicong
>
> > Reviewed-by: Jonathan Cameron <[email protected]>
> >
> >> ---
> >
> >> +
> >> +static int hisi_ptt_register_pmu(struct hisi_ptt *hisi_ptt)
> >> +{
> >> + u16 core_id, sicl_id;
> >> + char *pmu_name;
> >> + u32 reg;
> >> +
> >> + hisi_ptt->hisi_ptt_pmu = (struct pmu) {
> >> + .module = THIS_MODULE,
> >> + .capabilities = PERF_PMU_CAP_EXCLUSIVE | PERF_PMU_CAP_ITRACE,
> >> + .task_ctx_nr = perf_sw_context,
> >> + .attr_groups = hisi_ptt_pmu_groups,
> >> + .event_init = hisi_ptt_pmu_event_init,
> >> + .setup_aux = hisi_ptt_pmu_setup_aux,
> >> + .free_aux = hisi_ptt_pmu_free_aux,
> >> + .start = hisi_ptt_pmu_start,
> >> + .stop = hisi_ptt_pmu_stop,
> >> + .add = hisi_ptt_pmu_add,
> >> + .del = hisi_ptt_pmu_del,
> >> + };
> >> +
> >> + reg = readl(hisi_ptt->iobase + HISI_PTT_LOCATION);
> >> + core_id = FIELD_GET(HISI_PTT_CORE_ID, reg);
> >> + sicl_id = FIELD_GET(HISI_PTT_SICL_ID, reg);
> >> +
> >> + pmu_name = devm_kasprintf(&hisi_ptt->pdev->dev, GFP_KERNEL, "hisi_ptt%u_%u",
> >> + sicl_id, core_id);
> >> + if (!pmu_name)
> >> + return -ENOMEM;
> >> +
> >> + return perf_pmu_register(&hisi_ptt->hisi_ptt_pmu, pmu_name, -1);
> >
> > As below, you can put back the devm cleanup that you had in v4 now you
> > have modified how the filter cleanup is done to also be devm managed.
> >
> >> +}
> >> +
> >> /*
> >> * The DMA of PTT trace can only use direct mapping, due to some
> >> * hardware restriction. Check whether there is an IOMMU or the
> >> @@ -303,15 +825,32 @@ static int hisi_ptt_probe(struct pci_dev *pdev,
> >>
> >> pci_set_master(pdev);
> >>
> >> + ret = hisi_ptt_register_irq(hisi_ptt);
> >> + if (ret)
> >> + return ret;
> >> +
> >> ret = hisi_ptt_init_ctrls(hisi_ptt);
> >> if (ret) {
> >> pci_err(pdev, "failed to init controls, ret = %d.\n", ret);
> >> return ret;
> >> }
> >>
> >> + ret = hisi_ptt_register_pmu(hisi_ptt);
> >> + if (ret) {
> >> + pci_err(pdev, "failed to register pmu device, ret = %d", ret);
> >> + return ret;
> >> + }
> >> +
> >> return 0;
> >> }
> >>
> >> +void hisi_ptt_remove(struct pci_dev *pdev)
> >> +{
> >> + struct hisi_ptt *hisi_ptt = pci_get_drvdata(pdev);
> >> +
> >> + perf_pmu_unregister(&hisi_ptt->hisi_ptt_pmu);
> >
> > Now you have the filter cleanup occurring using a devm_add_action_or_reset()
> > there is no need to have a manual cleanup of this - you can
> > use the approach of a devm_add_action_or_reset like you had in v4.
> >
> > As it is the last call in the probe() order it will be the first one
> > called in the device managed cleanup.
> >
> >> +}
> >> +
> >
> >
> > .
> >
On Tue, 8 Mar 2022 16:49:25 +0800
Yicong Yang <[email protected]> wrote:
> Register PMU device of PTT trace, then users can use trace through perf
> command. The driver makes use of perf AUX trace and support following
> events to configure the trace:
>
> - filter: select Root port or Endpoint to trace
> - type: select the type of traced TLP headers
> - direction: select the direction of traced TLP headers
> - format: select the data format of the traced TLP headers
>
> This patch adds the PMU driver part of PTT trace. The perf command support
> of PTT trace is added in the following patch.
>
> Signed-off-by: Yicong Yang <[email protected]>
It seems to me that you ended up doing both suggestions for
how to clean up the remove order when it was meant to be
a question of picking one or the other.
Otherwise this looks good to me - so with that tidied up
Reviewed-by: Jonathan Cameron <[email protected]>
> ---
> +
> +static int hisi_ptt_register_pmu(struct hisi_ptt *hisi_ptt)
> +{
> + u16 core_id, sicl_id;
> + char *pmu_name;
> + u32 reg;
> +
> + hisi_ptt->hisi_ptt_pmu = (struct pmu) {
> + .module = THIS_MODULE,
> + .capabilities = PERF_PMU_CAP_EXCLUSIVE | PERF_PMU_CAP_ITRACE,
> + .task_ctx_nr = perf_sw_context,
> + .attr_groups = hisi_ptt_pmu_groups,
> + .event_init = hisi_ptt_pmu_event_init,
> + .setup_aux = hisi_ptt_pmu_setup_aux,
> + .free_aux = hisi_ptt_pmu_free_aux,
> + .start = hisi_ptt_pmu_start,
> + .stop = hisi_ptt_pmu_stop,
> + .add = hisi_ptt_pmu_add,
> + .del = hisi_ptt_pmu_del,
> + };
> +
> + reg = readl(hisi_ptt->iobase + HISI_PTT_LOCATION);
> + core_id = FIELD_GET(HISI_PTT_CORE_ID, reg);
> + sicl_id = FIELD_GET(HISI_PTT_SICL_ID, reg);
> +
> + pmu_name = devm_kasprintf(&hisi_ptt->pdev->dev, GFP_KERNEL, "hisi_ptt%u_%u",
> + sicl_id, core_id);
> + if (!pmu_name)
> + return -ENOMEM;
> +
> + return perf_pmu_register(&hisi_ptt->hisi_ptt_pmu, pmu_name, -1);
As below, you can put back the devm cleanup that you had in v4 now you
have modified how the filter cleanup is done to also be devm managed.
> +}
> +
> /*
> * The DMA of PTT trace can only use direct mapping, due to some
> * hardware restriction. Check whether there is an IOMMU or the
> @@ -303,15 +825,32 @@ static int hisi_ptt_probe(struct pci_dev *pdev,
>
> pci_set_master(pdev);
>
> + ret = hisi_ptt_register_irq(hisi_ptt);
> + if (ret)
> + return ret;
> +
> ret = hisi_ptt_init_ctrls(hisi_ptt);
> if (ret) {
> pci_err(pdev, "failed to init controls, ret = %d.\n", ret);
> return ret;
> }
>
> + ret = hisi_ptt_register_pmu(hisi_ptt);
> + if (ret) {
> + pci_err(pdev, "failed to register pmu device, ret = %d", ret);
> + return ret;
> + }
> +
> return 0;
> }
>
> +void hisi_ptt_remove(struct pci_dev *pdev)
> +{
> + struct hisi_ptt *hisi_ptt = pci_get_drvdata(pdev);
> +
> + perf_pmu_unregister(&hisi_ptt->hisi_ptt_pmu);
Now you have the filter cleanup occurring using a devm_add_action_or_reset()
there is no need to have a manual cleanup of this - you can
use the approach of a devm_add_action_or_reset like you had in v4.
As it is the last call in the probe() order it will be the first one
called in the device managed cleanup.
> +}
> +