| /* |
| * Loopback bridge driver for the Greybus loopback module. |
| * |
| * Copyright 2014 Google Inc. |
| * Copyright 2014 Linaro Ltd. |
| * |
| * Released under the GPLv2 only. |
| */ |
| |
| #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
| |
| #include <linux/kernel.h> |
| #include <linux/module.h> |
| #include <linux/mutex.h> |
| #include <linux/slab.h> |
| #include <linux/kthread.h> |
| #include <linux/delay.h> |
| #include <linux/random.h> |
| #include <linux/sizes.h> |
| #include <linux/cdev.h> |
| #include <linux/fs.h> |
| #include <linux/kfifo.h> |
| #include <linux/debugfs.h> |
| #include <linux/list_sort.h> |
| #include <linux/spinlock.h> |
| #include <linux/workqueue.h> |
| #include <linux/atomic.h> |
| |
| #include <asm/div64.h> |
| |
| #include "greybus.h" |
| #include "connection.h" |
| |
| #define NSEC_PER_DAY 86400000000000ULL |
| |
| struct gb_loopback_stats { |
| u32 min; |
| u32 max; |
| u64 sum; |
| u32 count; |
| }; |
| |
| struct gb_loopback_device { |
| struct dentry *root; |
| u32 count; |
| size_t size_max; |
| |
| /* We need to take a lock in atomic context */ |
| spinlock_t lock; |
| struct list_head list; |
| struct list_head list_op_async; |
| wait_queue_head_t wq; |
| }; |
| |
| static struct gb_loopback_device gb_dev; |
| |
| struct gb_loopback_async_operation { |
| struct gb_loopback *gb; |
| struct gb_operation *operation; |
| struct timeval ts; |
| struct timer_list timer; |
| struct list_head entry; |
| struct work_struct work; |
| struct kref kref; |
| bool pending; |
| int (*completion)(struct gb_loopback_async_operation *op_async); |
| }; |
| |
| struct gb_loopback { |
| struct gb_connection *connection; |
| |
| struct dentry *file; |
| struct kfifo kfifo_lat; |
| struct kfifo kfifo_ts; |
| struct mutex mutex; |
| struct task_struct *task; |
| struct list_head entry; |
| struct device *dev; |
| wait_queue_head_t wq; |
| wait_queue_head_t wq_completion; |
| atomic_t outstanding_operations; |
| |
| /* Per connection stats */ |
| struct gb_loopback_stats latency; |
| struct gb_loopback_stats throughput; |
| struct gb_loopback_stats requests_per_second; |
| struct gb_loopback_stats apbridge_unipro_latency; |
| struct gb_loopback_stats gpbridge_firmware_latency; |
| |
| int type; |
| int async; |
| int id; |
| u32 size; |
| u32 iteration_max; |
| u32 iteration_count; |
| int us_wait; |
| u32 error; |
| u32 requests_completed; |
| u32 requests_timedout; |
| u32 timeout; |
| u32 jiffy_timeout; |
| u32 timeout_min; |
| u32 timeout_max; |
| u32 outstanding_operations_max; |
| u32 lbid; |
| u64 elapsed_nsecs; |
| u32 apbridge_latency_ts; |
| u32 gpbridge_latency_ts; |
| }; |
| |
| static struct class loopback_class = { |
| .name = "gb_loopback", |
| .owner = THIS_MODULE, |
| }; |
| static DEFINE_IDA(loopback_ida); |
| |
| /* Min/max values in jiffies */ |
| #define GB_LOOPBACK_TIMEOUT_MIN 1 |
| #define GB_LOOPBACK_TIMEOUT_MAX 10000 |
| |
| #define GB_LOOPBACK_FIFO_DEFAULT 8192 |
| |
| static unsigned kfifo_depth = GB_LOOPBACK_FIFO_DEFAULT; |
| module_param(kfifo_depth, uint, 0444); |
| |
| /* Maximum size of any one send data buffer we support */ |
| #define MAX_PACKET_SIZE (PAGE_SIZE * 2) |
| |
| #define GB_LOOPBACK_US_WAIT_MAX 1000000 |
| |
| /* interface sysfs attributes */ |
| #define gb_loopback_ro_attr(field) \ |
| static ssize_t field##_show(struct device *dev, \ |
| struct device_attribute *attr, \ |
| char *buf) \ |
| { \ |
| struct gb_loopback *gb = dev_get_drvdata(dev); \ |
| return sprintf(buf, "%u\n", gb->field); \ |
| } \ |
| static DEVICE_ATTR_RO(field) |
| |
| #define gb_loopback_ro_stats_attr(name, field, type) \ |
| static ssize_t name##_##field##_show(struct device *dev, \ |
| struct device_attribute *attr, \ |
| char *buf) \ |
| { \ |
| struct gb_loopback *gb = dev_get_drvdata(dev); \ |
| return sprintf(buf, "%"#type"\n", gb->name.field); \ |
| } \ |
| static DEVICE_ATTR_RO(name##_##field) |
| |
| #define gb_loopback_ro_avg_attr(name) \ |
| static ssize_t name##_avg_show(struct device *dev, \ |
| struct device_attribute *attr, \ |
| char *buf) \ |
| { \ |
| struct gb_loopback_stats *stats; \ |
| struct gb_loopback *gb; \ |
| u64 avg; \ |
| u32 count, rem; \ |
| gb = dev_get_drvdata(dev); \ |
| stats = &gb->name; \ |
| count = stats->count ? stats->count : 1; \ |
| avg = stats->sum + count / 2; /* round closest */ \ |
| rem = do_div(avg, count); \ |
| return sprintf(buf, "%llu.%06u\n", avg, 1000000 * rem / count); \ |
| } \ |
| static DEVICE_ATTR_RO(name##_avg) |
| |
| #define gb_loopback_stats_attrs(field) \ |
| gb_loopback_ro_stats_attr(field, min, u); \ |
| gb_loopback_ro_stats_attr(field, max, u); \ |
| gb_loopback_ro_avg_attr(field) |
| |
| #define gb_loopback_attr(field, type) \ |
| static ssize_t field##_show(struct device *dev, \ |
| struct device_attribute *attr, \ |
| char *buf) \ |
| { \ |
| struct gb_loopback *gb = dev_get_drvdata(dev); \ |
| return sprintf(buf, "%"#type"\n", gb->field); \ |
| } \ |
| static ssize_t field##_store(struct device *dev, \ |
| struct device_attribute *attr, \ |
| const char *buf, \ |
| size_t len) \ |
| { \ |
| int ret; \ |
| struct gb_loopback *gb = dev_get_drvdata(dev); \ |
| mutex_lock(&gb->mutex); \ |
| ret = sscanf(buf, "%"#type, &gb->field); \ |
| if (ret != 1) \ |
| len = -EINVAL; \ |
| else \ |
| gb_loopback_check_attr(gb, bundle); \ |
| mutex_unlock(&gb->mutex); \ |
| return len; \ |
| } \ |
| static DEVICE_ATTR_RW(field) |
| |
| #define gb_dev_loopback_ro_attr(field, conn) \ |
| static ssize_t field##_show(struct device *dev, \ |
| struct device_attribute *attr, \ |
| char *buf) \ |
| { \ |
| struct gb_loopback *gb = dev_get_drvdata(dev); \ |
| return sprintf(buf, "%u\n", gb->field); \ |
| } \ |
| static DEVICE_ATTR_RO(field) |
| |
| #define gb_dev_loopback_rw_attr(field, type) \ |
| static ssize_t field##_show(struct device *dev, \ |
| struct device_attribute *attr, \ |
| char *buf) \ |
| { \ |
| struct gb_loopback *gb = dev_get_drvdata(dev); \ |
| return sprintf(buf, "%"#type"\n", gb->field); \ |
| } \ |
| static ssize_t field##_store(struct device *dev, \ |
| struct device_attribute *attr, \ |
| const char *buf, \ |
| size_t len) \ |
| { \ |
| int ret; \ |
| struct gb_loopback *gb = dev_get_drvdata(dev); \ |
| mutex_lock(&gb->mutex); \ |
| ret = sscanf(buf, "%"#type, &gb->field); \ |
| if (ret != 1) \ |
| len = -EINVAL; \ |
| else \ |
| gb_loopback_check_attr(gb); \ |
| mutex_unlock(&gb->mutex); \ |
| return len; \ |
| } \ |
| static DEVICE_ATTR_RW(field) |
| |
| static void gb_loopback_reset_stats(struct gb_loopback *gb); |
| static void gb_loopback_check_attr(struct gb_loopback *gb) |
| { |
| if (gb->us_wait > GB_LOOPBACK_US_WAIT_MAX) |
| gb->us_wait = GB_LOOPBACK_US_WAIT_MAX; |
| if (gb->size > gb_dev.size_max) |
| gb->size = gb_dev.size_max; |
| gb->requests_timedout = 0; |
| gb->requests_completed = 0; |
| gb->iteration_count = 0; |
| gb->error = 0; |
| |
| if (kfifo_depth < gb->iteration_max) { |
| dev_warn(gb->dev, |
| "cannot log bytes %u kfifo_depth %u\n", |
| gb->iteration_max, kfifo_depth); |
| } |
| kfifo_reset_out(&gb->kfifo_lat); |
| kfifo_reset_out(&gb->kfifo_ts); |
| |
| switch (gb->type) { |
| case GB_LOOPBACK_TYPE_PING: |
| case GB_LOOPBACK_TYPE_TRANSFER: |
| case GB_LOOPBACK_TYPE_SINK: |
| gb->jiffy_timeout = usecs_to_jiffies(gb->timeout); |
| if (!gb->jiffy_timeout) |
| gb->jiffy_timeout = GB_LOOPBACK_TIMEOUT_MIN; |
| else if (gb->jiffy_timeout > GB_LOOPBACK_TIMEOUT_MAX) |
| gb->jiffy_timeout = GB_LOOPBACK_TIMEOUT_MAX; |
| gb_loopback_reset_stats(gb); |
| wake_up(&gb->wq); |
| break; |
| default: |
| gb->type = 0; |
| break; |
| } |
| } |
| |
| /* Time to send and receive one message */ |
| gb_loopback_stats_attrs(latency); |
| /* Number of requests sent per second on this cport */ |
| gb_loopback_stats_attrs(requests_per_second); |
| /* Quantity of data sent and received on this cport */ |
| gb_loopback_stats_attrs(throughput); |
| /* Latency across the UniPro link from APBridge's perspective */ |
| gb_loopback_stats_attrs(apbridge_unipro_latency); |
| /* Firmware induced overhead in the GPBridge */ |
| gb_loopback_stats_attrs(gpbridge_firmware_latency); |
| |
| /* Number of errors encountered during loop */ |
| gb_loopback_ro_attr(error); |
| /* Number of requests successfully completed async */ |
| gb_loopback_ro_attr(requests_completed); |
| /* Number of requests timed out async */ |
| gb_loopback_ro_attr(requests_timedout); |
| /* Timeout minimum in useconds */ |
| gb_loopback_ro_attr(timeout_min); |
| /* Timeout minimum in useconds */ |
| gb_loopback_ro_attr(timeout_max); |
| |
| /* |
| * Type of loopback message to send based on protocol type definitions |
| * 0 => Don't send message |
| * 2 => Send ping message continuously (message without payload) |
| * 3 => Send transfer message continuously (message with payload, |
| * payload returned in response) |
| * 4 => Send a sink message (message with payload, no payload in response) |
| */ |
| gb_dev_loopback_rw_attr(type, d); |
| /* Size of transfer message payload: 0-4096 bytes */ |
| gb_dev_loopback_rw_attr(size, u); |
| /* Time to wait between two messages: 0-1000 ms */ |
| gb_dev_loopback_rw_attr(us_wait, d); |
| /* Maximum iterations for a given operation: 1-(2^32-1), 0 implies infinite */ |
| gb_dev_loopback_rw_attr(iteration_max, u); |
| /* The current index of the for (i = 0; i < iteration_max; i++) loop */ |
| gb_dev_loopback_ro_attr(iteration_count, false); |
| /* A flag to indicate synchronous or asynchronous operations */ |
| gb_dev_loopback_rw_attr(async, u); |
| /* Timeout of an individual asynchronous request */ |
| gb_dev_loopback_rw_attr(timeout, u); |
| /* Maximum number of in-flight operations before back-off */ |
| gb_dev_loopback_rw_attr(outstanding_operations_max, u); |
| |
| static struct attribute *loopback_attrs[] = { |
| &dev_attr_latency_min.attr, |
| &dev_attr_latency_max.attr, |
| &dev_attr_latency_avg.attr, |
| &dev_attr_requests_per_second_min.attr, |
| &dev_attr_requests_per_second_max.attr, |
| &dev_attr_requests_per_second_avg.attr, |
| &dev_attr_throughput_min.attr, |
| &dev_attr_throughput_max.attr, |
| &dev_attr_throughput_avg.attr, |
| &dev_attr_apbridge_unipro_latency_min.attr, |
| &dev_attr_apbridge_unipro_latency_max.attr, |
| &dev_attr_apbridge_unipro_latency_avg.attr, |
| &dev_attr_gpbridge_firmware_latency_min.attr, |
| &dev_attr_gpbridge_firmware_latency_max.attr, |
| &dev_attr_gpbridge_firmware_latency_avg.attr, |
| &dev_attr_type.attr, |
| &dev_attr_size.attr, |
| &dev_attr_us_wait.attr, |
| &dev_attr_iteration_count.attr, |
| &dev_attr_iteration_max.attr, |
| &dev_attr_async.attr, |
| &dev_attr_error.attr, |
| &dev_attr_requests_completed.attr, |
| &dev_attr_requests_timedout.attr, |
| &dev_attr_timeout.attr, |
| &dev_attr_outstanding_operations_max.attr, |
| &dev_attr_timeout_min.attr, |
| &dev_attr_timeout_max.attr, |
| NULL, |
| }; |
| ATTRIBUTE_GROUPS(loopback); |
| |
| static void gb_loopback_calculate_stats(struct gb_loopback *gb); |
| |
| static u32 gb_loopback_nsec_to_usec_latency(u64 elapsed_nsecs) |
| { |
| u32 lat; |
| |
| do_div(elapsed_nsecs, NSEC_PER_USEC); |
| lat = elapsed_nsecs; |
| return lat; |
| } |
| |
| static u64 __gb_loopback_calc_latency(u64 t1, u64 t2) |
| { |
| if (t2 > t1) |
| return t2 - t1; |
| else |
| return NSEC_PER_DAY - t2 + t1; |
| } |
| |
| static u64 gb_loopback_calc_latency(struct timeval *ts, struct timeval *te) |
| { |
| u64 t1, t2; |
| |
| t1 = timeval_to_ns(ts); |
| t2 = timeval_to_ns(te); |
| |
| return __gb_loopback_calc_latency(t1, t2); |
| } |
| |
| static void gb_loopback_push_latency_ts(struct gb_loopback *gb, |
| struct timeval *ts, struct timeval *te) |
| { |
| kfifo_in(&gb->kfifo_ts, (unsigned char *)ts, sizeof(*ts)); |
| kfifo_in(&gb->kfifo_ts, (unsigned char *)te, sizeof(*te)); |
| } |
| |
| static int gb_loopback_operation_sync(struct gb_loopback *gb, int type, |
| void *request, int request_size, |
| void *response, int response_size) |
| { |
| struct gb_operation *operation; |
| struct timeval ts, te; |
| int ret; |
| |
| do_gettimeofday(&ts); |
| operation = gb_operation_create(gb->connection, type, request_size, |
| response_size, GFP_KERNEL); |
| if (!operation) { |
| ret = -ENOMEM; |
| goto error; |
| } |
| |
| if (request_size) |
| memcpy(operation->request->payload, request, request_size); |
| |
| ret = gb_operation_request_send_sync(operation); |
| if (ret) { |
| dev_err(&gb->connection->bundle->dev, |
| "synchronous operation failed: %d\n", ret); |
| } else { |
| if (response_size == operation->response->payload_size) { |
| memcpy(response, operation->response->payload, |
| response_size); |
| } else { |
| dev_err(&gb->connection->bundle->dev, |
| "response size %zu expected %d\n", |
| operation->response->payload_size, |
| response_size); |
| } |
| } |
| |
| gb_operation_put(operation); |
| |
| error: |
| do_gettimeofday(&te); |
| |
| /* Calculate the total time the message took */ |
| gb_loopback_push_latency_ts(gb, &ts, &te); |
| gb->elapsed_nsecs = gb_loopback_calc_latency(&ts, &te); |
| |
| return ret; |
| } |
| |
| static void __gb_loopback_async_operation_destroy(struct kref *kref) |
| { |
| struct gb_loopback_async_operation *op_async; |
| |
| op_async = container_of(kref, struct gb_loopback_async_operation, kref); |
| |
| list_del(&op_async->entry); |
| if (op_async->operation) |
| gb_operation_put(op_async->operation); |
| atomic_dec(&op_async->gb->outstanding_operations); |
| wake_up(&op_async->gb->wq_completion); |
| kfree(op_async); |
| } |
| |
| static void gb_loopback_async_operation_get(struct gb_loopback_async_operation |
| *op_async) |
| { |
| kref_get(&op_async->kref); |
| } |
| |
| static void gb_loopback_async_operation_put(struct gb_loopback_async_operation |
| *op_async) |
| { |
| unsigned long flags; |
| |
| spin_lock_irqsave(&gb_dev.lock, flags); |
| kref_put(&op_async->kref, __gb_loopback_async_operation_destroy); |
| spin_unlock_irqrestore(&gb_dev.lock, flags); |
| } |
| |
| static struct gb_loopback_async_operation * |
| gb_loopback_operation_find(u16 id) |
| { |
| struct gb_loopback_async_operation *op_async; |
| bool found = false; |
| unsigned long flags; |
| |
| spin_lock_irqsave(&gb_dev.lock, flags); |
| list_for_each_entry(op_async, &gb_dev.list_op_async, entry) { |
| if (op_async->operation->id == id) { |
| gb_loopback_async_operation_get(op_async); |
| found = true; |
| break; |
| } |
| } |
| spin_unlock_irqrestore(&gb_dev.lock, flags); |
| |
| return found ? op_async : NULL; |
| } |
| |
| static void gb_loopback_async_wait_all(struct gb_loopback *gb) |
| { |
| wait_event(gb->wq_completion, |
| !atomic_read(&gb->outstanding_operations)); |
| } |
| |
| static void gb_loopback_async_operation_callback(struct gb_operation *operation) |
| { |
| struct gb_loopback_async_operation *op_async; |
| struct gb_loopback *gb; |
| struct timeval te; |
| bool err = false; |
| |
| do_gettimeofday(&te); |
| op_async = gb_loopback_operation_find(operation->id); |
| if (!op_async) |
| return; |
| |
| gb = op_async->gb; |
| mutex_lock(&gb->mutex); |
| |
| if (!op_async->pending || gb_operation_result(operation)) { |
| err = true; |
| } else { |
| if (op_async->completion) |
| if (op_async->completion(op_async)) |
| err = true; |
| } |
| |
| if (err) { |
| gb->error++; |
| } else { |
| gb->requests_completed++; |
| gb_loopback_push_latency_ts(gb, &op_async->ts, &te); |
| gb->elapsed_nsecs = gb_loopback_calc_latency(&op_async->ts, |
| &te); |
| gb_loopback_calculate_stats(gb); |
| } |
| |
| if (op_async->pending) { |
| gb->iteration_count++; |
| op_async->pending = false; |
| del_timer_sync(&op_async->timer); |
| gb_loopback_async_operation_put(op_async); |
| } |
| mutex_unlock(&gb->mutex); |
| |
| dev_dbg(&gb->connection->bundle->dev, "complete operation %d\n", |
| operation->id); |
| |
| gb_loopback_async_operation_put(op_async); |
| } |
| |
| static void gb_loopback_async_operation_work(struct work_struct *work) |
| { |
| struct gb_loopback *gb; |
| struct gb_operation *operation; |
| struct gb_loopback_async_operation *op_async; |
| |
| op_async = container_of(work, struct gb_loopback_async_operation, work); |
| gb = op_async->gb; |
| operation = op_async->operation; |
| |
| mutex_lock(&gb->mutex); |
| if (op_async->pending) { |
| gb->requests_timedout++; |
| gb->error++; |
| gb->iteration_count++; |
| op_async->pending = false; |
| gb_loopback_async_operation_put(op_async); |
| } |
| mutex_unlock(&gb->mutex); |
| |
| dev_dbg(&gb->connection->bundle->dev, "timeout operation %d\n", |
| operation->id); |
| |
| gb_operation_cancel(operation, -ETIMEDOUT); |
| gb_loopback_async_operation_put(op_async); |
| } |
| |
| static void gb_loopback_async_operation_timeout(unsigned long data) |
| { |
| struct gb_loopback_async_operation *op_async; |
| u16 id = data; |
| |
| op_async = gb_loopback_operation_find(id); |
| if (!op_async) { |
| pr_err("operation %d not found - time out ?\n", id); |
| return; |
| } |
| schedule_work(&op_async->work); |
| } |
| |
| static int gb_loopback_async_operation(struct gb_loopback *gb, int type, |
| void *request, int request_size, |
| int response_size, |
| void *completion) |
| { |
| struct gb_loopback_async_operation *op_async; |
| struct gb_operation *operation; |
| int ret; |
| unsigned long flags; |
| |
| op_async = kzalloc(sizeof(*op_async), GFP_KERNEL); |
| if (!op_async) |
| return -ENOMEM; |
| |
| INIT_WORK(&op_async->work, gb_loopback_async_operation_work); |
| init_timer(&op_async->timer); |
| kref_init(&op_async->kref); |
| |
| operation = gb_operation_create(gb->connection, type, request_size, |
| response_size, GFP_KERNEL); |
| if (!operation) { |
| kfree(op_async); |
| return -ENOMEM; |
| } |
| |
| if (request_size) |
| memcpy(operation->request->payload, request, request_size); |
| |
| op_async->gb = gb; |
| op_async->operation = operation; |
| op_async->completion = completion; |
| |
| spin_lock_irqsave(&gb_dev.lock, flags); |
| list_add_tail(&op_async->entry, &gb_dev.list_op_async); |
| spin_unlock_irqrestore(&gb_dev.lock, flags); |
| |
| do_gettimeofday(&op_async->ts); |
| op_async->pending = true; |
| atomic_inc(&gb->outstanding_operations); |
| ret = gb_operation_request_send(operation, |
| gb_loopback_async_operation_callback, |
| GFP_KERNEL); |
| if (ret) |
| goto error; |
| |
| op_async->timer.function = gb_loopback_async_operation_timeout; |
| op_async->timer.expires = jiffies + gb->jiffy_timeout; |
| op_async->timer.data = (unsigned long)operation->id; |
| add_timer(&op_async->timer); |
| |
| return ret; |
| error: |
| gb_loopback_async_operation_put(op_async); |
| return ret; |
| } |
| |
| static int gb_loopback_sync_sink(struct gb_loopback *gb, u32 len) |
| { |
| struct gb_loopback_transfer_request *request; |
| int retval; |
| |
| request = kmalloc(len + sizeof(*request), GFP_KERNEL); |
| if (!request) |
| return -ENOMEM; |
| |
| request->len = cpu_to_le32(len); |
| retval = gb_loopback_operation_sync(gb, GB_LOOPBACK_TYPE_SINK, |
| request, len + sizeof(*request), |
| NULL, 0); |
| kfree(request); |
| return retval; |
| } |
| |
| static int gb_loopback_sync_transfer(struct gb_loopback *gb, u32 len) |
| { |
| struct gb_loopback_transfer_request *request; |
| struct gb_loopback_transfer_response *response; |
| int retval; |
| |
| gb->apbridge_latency_ts = 0; |
| gb->gpbridge_latency_ts = 0; |
| |
| request = kmalloc(len + sizeof(*request), GFP_KERNEL); |
| if (!request) |
| return -ENOMEM; |
| response = kmalloc(len + sizeof(*response), GFP_KERNEL); |
| if (!response) { |
| kfree(request); |
| return -ENOMEM; |
| } |
| |
| memset(request->data, 0x5A, len); |
| |
| request->len = cpu_to_le32(len); |
| retval = gb_loopback_operation_sync(gb, GB_LOOPBACK_TYPE_TRANSFER, |
| request, len + sizeof(*request), |
| response, len + sizeof(*response)); |
| if (retval) |
| goto gb_error; |
| |
| if (memcmp(request->data, response->data, len)) { |
| dev_err(&gb->connection->bundle->dev, |
| "Loopback Data doesn't match\n"); |
| retval = -EREMOTEIO; |
| } |
| gb->apbridge_latency_ts = (u32)__le32_to_cpu(response->reserved0); |
| gb->gpbridge_latency_ts = (u32)__le32_to_cpu(response->reserved1); |
| |
| gb_error: |
| kfree(request); |
| kfree(response); |
| |
| return retval; |
| } |
| |
| static int gb_loopback_sync_ping(struct gb_loopback *gb) |
| { |
| return gb_loopback_operation_sync(gb, GB_LOOPBACK_TYPE_PING, |
| NULL, 0, NULL, 0); |
| } |
| |
| static int gb_loopback_async_sink(struct gb_loopback *gb, u32 len) |
| { |
| struct gb_loopback_transfer_request *request; |
| int retval; |
| |
| request = kmalloc(len + sizeof(*request), GFP_KERNEL); |
| if (!request) |
| return -ENOMEM; |
| |
| request->len = cpu_to_le32(len); |
| retval = gb_loopback_async_operation(gb, GB_LOOPBACK_TYPE_SINK, |
| request, len + sizeof(*request), |
| 0, NULL); |
| kfree(request); |
| return retval; |
| } |
| |
| static int gb_loopback_async_transfer_complete( |
| struct gb_loopback_async_operation *op_async) |
| { |
| struct gb_loopback *gb; |
| struct gb_operation *operation; |
| struct gb_loopback_transfer_request *request; |
| struct gb_loopback_transfer_response *response; |
| size_t len; |
| int retval = 0; |
| |
| gb = op_async->gb; |
| operation = op_async->operation; |
| request = operation->request->payload; |
| response = operation->response->payload; |
| len = le32_to_cpu(request->len); |
| |
| if (memcmp(request->data, response->data, len)) { |
| dev_err(&gb->connection->bundle->dev, |
| "Loopback Data doesn't match operation id %d\n", |
| operation->id); |
| retval = -EREMOTEIO; |
| } else { |
| gb->apbridge_latency_ts = |
| (u32)__le32_to_cpu(response->reserved0); |
| gb->gpbridge_latency_ts = |
| (u32)__le32_to_cpu(response->reserved1); |
| } |
| |
| return retval; |
| } |
| |
| static int gb_loopback_async_transfer(struct gb_loopback *gb, u32 len) |
| { |
| struct gb_loopback_transfer_request *request; |
| int retval, response_len; |
| |
| request = kmalloc(len + sizeof(*request), GFP_KERNEL); |
| if (!request) |
| return -ENOMEM; |
| |
| memset(request->data, 0x5A, len); |
| |
| request->len = cpu_to_le32(len); |
| response_len = sizeof(struct gb_loopback_transfer_response); |
| retval = gb_loopback_async_operation(gb, GB_LOOPBACK_TYPE_TRANSFER, |
| request, len + sizeof(*request), |
| len + response_len, |
| gb_loopback_async_transfer_complete); |
| if (retval) |
| goto gb_error; |
| |
| gb_error: |
| kfree(request); |
| return retval; |
| } |
| |
| static int gb_loopback_async_ping(struct gb_loopback *gb) |
| { |
| return gb_loopback_async_operation(gb, GB_LOOPBACK_TYPE_PING, |
| NULL, 0, 0, NULL); |
| } |
| |
| static int gb_loopback_request_recv(u8 type, struct gb_operation *operation) |
| { |
| struct gb_connection *connection = operation->connection; |
| struct gb_loopback_transfer_request *request; |
| struct gb_loopback_transfer_response *response; |
| struct device *dev = &connection->bundle->dev; |
| size_t len; |
| |
| /* By convention, the AP initiates the version operation */ |
| switch (type) { |
| case GB_REQUEST_TYPE_PROTOCOL_VERSION: |
| dev_err(dev, "module-initiated version operation\n"); |
| return -EINVAL; |
| case GB_LOOPBACK_TYPE_PING: |
| case GB_LOOPBACK_TYPE_SINK: |
| return 0; |
| case GB_LOOPBACK_TYPE_TRANSFER: |
| if (operation->request->payload_size < sizeof(*request)) { |
| dev_err(dev, "transfer request too small (%zu < %zu)\n", |
| operation->request->payload_size, |
| sizeof(*request)); |
| return -EINVAL; /* -EMSGSIZE */ |
| } |
| request = operation->request->payload; |
| len = le32_to_cpu(request->len); |
| if (len > gb_dev.size_max) { |
| dev_err(dev, "transfer request too large (%zu > %zu)\n", |
| len, gb_dev.size_max); |
| return -EINVAL; |
| } |
| |
| if (!gb_operation_response_alloc(operation, |
| len + sizeof(*response), GFP_KERNEL)) { |
| dev_err(dev, "error allocating response\n"); |
| return -ENOMEM; |
| } |
| response = operation->response->payload; |
| response->len = cpu_to_le32(len); |
| if (len) |
| memcpy(response->data, request->data, len); |
| |
| return 0; |
| default: |
| dev_err(dev, "unsupported request: %u\n", type); |
| return -EINVAL; |
| } |
| } |
| |
| static void gb_loopback_reset_stats(struct gb_loopback *gb) |
| { |
| struct gb_loopback_stats reset = { |
| .min = U32_MAX, |
| }; |
| |
| /* Reset per-connection stats */ |
| memcpy(&gb->latency, &reset, |
| sizeof(struct gb_loopback_stats)); |
| memcpy(&gb->throughput, &reset, |
| sizeof(struct gb_loopback_stats)); |
| memcpy(&gb->requests_per_second, &reset, |
| sizeof(struct gb_loopback_stats)); |
| memcpy(&gb->apbridge_unipro_latency, &reset, |
| sizeof(struct gb_loopback_stats)); |
| memcpy(&gb->gpbridge_firmware_latency, &reset, |
| sizeof(struct gb_loopback_stats)); |
| |
| /* Should be initialized at least once per transaction set */ |
| gb->apbridge_latency_ts = 0; |
| gb->gpbridge_latency_ts = 0; |
| } |
| |
| static void gb_loopback_update_stats(struct gb_loopback_stats *stats, u32 val) |
| { |
| if (stats->min > val) |
| stats->min = val; |
| if (stats->max < val) |
| stats->max = val; |
| stats->sum += val; |
| stats->count++; |
| } |
| |
| static void gb_loopback_requests_update(struct gb_loopback *gb, u32 latency) |
| { |
| u32 req = USEC_PER_SEC; |
| |
| do_div(req, latency); |
| gb_loopback_update_stats(&gb->requests_per_second, req); |
| } |
| |
| static void gb_loopback_throughput_update(struct gb_loopback *gb, u32 latency) |
| { |
| u32 throughput; |
| u32 aggregate_size = sizeof(struct gb_operation_msg_hdr) * 2; |
| |
| switch (gb->type) { |
| case GB_LOOPBACK_TYPE_PING: |
| break; |
| case GB_LOOPBACK_TYPE_SINK: |
| aggregate_size += sizeof(struct gb_loopback_transfer_request) + |
| gb->size; |
| break; |
| case GB_LOOPBACK_TYPE_TRANSFER: |
| aggregate_size += sizeof(struct gb_loopback_transfer_request) + |
| sizeof(struct gb_loopback_transfer_response) + |
| gb->size * 2; |
| break; |
| default: |
| return; |
| } |
| |
| /* Calculate bytes per second */ |
| throughput = USEC_PER_SEC; |
| do_div(throughput, latency); |
| throughput *= aggregate_size; |
| gb_loopback_update_stats(&gb->throughput, throughput); |
| } |
| |
| static void gb_loopback_calculate_stats(struct gb_loopback *gb) |
| { |
| u32 lat; |
| |
| /* Express latency in terms of microseconds */ |
| lat = gb_loopback_nsec_to_usec_latency(gb->elapsed_nsecs); |
| |
| /* Log latency stastic */ |
| gb_loopback_update_stats(&gb->latency, lat); |
| |
| /* Raw latency log on a per thread basis */ |
| kfifo_in(&gb->kfifo_lat, (unsigned char *)&lat, sizeof(lat)); |
| |
| /* Log throughput and requests using latency as benchmark */ |
| gb_loopback_throughput_update(gb, lat); |
| gb_loopback_requests_update(gb, lat); |
| |
| /* Log the firmware supplied latency values */ |
| gb_loopback_update_stats(&gb->apbridge_unipro_latency, |
| gb->apbridge_latency_ts); |
| gb_loopback_update_stats(&gb->gpbridge_firmware_latency, |
| gb->gpbridge_latency_ts); |
| } |
| |
| static void gb_loopback_async_wait_to_send(struct gb_loopback *gb) |
| { |
| if (!(gb->async && gb->outstanding_operations_max)) |
| return; |
| wait_event_interruptible(gb->wq_completion, |
| (atomic_read(&gb->outstanding_operations) < |
| gb->outstanding_operations_max) || |
| kthread_should_stop()); |
| } |
| |
| static int gb_loopback_fn(void *data) |
| { |
| int error = 0; |
| int us_wait = 0; |
| int type; |
| u32 size; |
| u32 send_count = 0; |
| struct gb_loopback *gb = data; |
| |
| while (1) { |
| if (!gb->type) |
| wait_event_interruptible(gb->wq, gb->type || |
| kthread_should_stop()); |
| if (kthread_should_stop()) |
| break; |
| |
| /* Limit the maximum number of in-flight async operations */ |
| gb_loopback_async_wait_to_send(gb); |
| if (kthread_should_stop()) |
| break; |
| |
| mutex_lock(&gb->mutex); |
| sysfs_notify(&gb->connection->bundle->dev.kobj, |
| NULL, "iteration_count"); |
| |
| /* Optionally terminate */ |
| if (send_count == gb->iteration_max) { |
| gb->type = 0; |
| send_count = 0; |
| mutex_unlock(&gb->mutex); |
| continue; |
| } |
| size = gb->size; |
| us_wait = gb->us_wait; |
| type = gb->type; |
| mutex_unlock(&gb->mutex); |
| |
| /* Else operations to perform */ |
| if (gb->async) { |
| if (type == GB_LOOPBACK_TYPE_PING) { |
| error = gb_loopback_async_ping(gb); |
| gb_loopback_calculate_stats(gb); |
| } else if (type == GB_LOOPBACK_TYPE_TRANSFER) { |
| error = gb_loopback_async_transfer(gb, size); |
| } else if (type == GB_LOOPBACK_TYPE_SINK) { |
| error = gb_loopback_async_sink(gb, size); |
| } |
| |
| if (error) |
| gb->error++; |
| } else { |
| /* We are effectively single threaded here */ |
| if (type == GB_LOOPBACK_TYPE_PING) |
| error = gb_loopback_sync_ping(gb); |
| else if (type == GB_LOOPBACK_TYPE_TRANSFER) |
| error = gb_loopback_sync_transfer(gb, size); |
| else if (type == GB_LOOPBACK_TYPE_SINK) |
| error = gb_loopback_sync_sink(gb, size); |
| |
| if (error) |
| gb->error++; |
| gb->iteration_count++; |
| gb_loopback_calculate_stats(gb); |
| } |
| send_count++; |
| if (us_wait) |
| udelay(us_wait); |
| } |
| return 0; |
| } |
| |
| static int gb_loopback_dbgfs_latency_show_common(struct seq_file *s, |
| struct kfifo *kfifo, |
| struct mutex *mutex) |
| { |
| u32 latency; |
| int retval; |
| |
| if (kfifo_len(kfifo) == 0) { |
| retval = -EAGAIN; |
| goto done; |
| } |
| |
| mutex_lock(mutex); |
| retval = kfifo_out(kfifo, &latency, sizeof(latency)); |
| if (retval > 0) { |
| seq_printf(s, "%u", latency); |
| retval = 0; |
| } |
| mutex_unlock(mutex); |
| done: |
| return retval; |
| } |
| |
| static int gb_loopback_dbgfs_latency_show(struct seq_file *s, void *unused) |
| { |
| struct gb_loopback *gb = s->private; |
| |
| return gb_loopback_dbgfs_latency_show_common(s, &gb->kfifo_lat, |
| &gb->mutex); |
| } |
| |
| static int gb_loopback_latency_open(struct inode *inode, struct file *file) |
| { |
| return single_open(file, gb_loopback_dbgfs_latency_show, |
| inode->i_private); |
| } |
| |
| static const struct file_operations gb_loopback_debugfs_latency_ops = { |
| .open = gb_loopback_latency_open, |
| .read = seq_read, |
| .llseek = seq_lseek, |
| .release = single_release, |
| }; |
| |
| static int gb_loopback_bus_id_compare(void *priv, struct list_head *lha, |
| struct list_head *lhb) |
| { |
| struct gb_loopback *a = list_entry(lha, struct gb_loopback, entry); |
| struct gb_loopback *b = list_entry(lhb, struct gb_loopback, entry); |
| struct gb_connection *ca = a->connection; |
| struct gb_connection *cb = b->connection; |
| |
| if (ca->bundle->intf->interface_id < cb->bundle->intf->interface_id) |
| return -1; |
| if (cb->bundle->intf->interface_id < ca->bundle->intf->interface_id) |
| return 1; |
| if (ca->bundle->id < cb->bundle->id) |
| return -1; |
| if (cb->bundle->id < ca->bundle->id) |
| return 1; |
| if (ca->intf_cport_id < cb->intf_cport_id) |
| return -1; |
| else if (cb->intf_cport_id < ca->intf_cport_id) |
| return 1; |
| |
| return 0; |
| } |
| |
| static void gb_loopback_insert_id(struct gb_loopback *gb) |
| { |
| struct gb_loopback *gb_list; |
| u32 new_lbid = 0; |
| |
| /* perform an insertion sort */ |
| list_add_tail(&gb->entry, &gb_dev.list); |
| list_sort(NULL, &gb_dev.list, gb_loopback_bus_id_compare); |
| list_for_each_entry(gb_list, &gb_dev.list, entry) { |
| gb_list->lbid = 1 << new_lbid; |
| new_lbid++; |
| } |
| } |
| |
| #define DEBUGFS_NAMELEN 32 |
| |
| static int gb_loopback_connection_init(struct gb_connection *connection) |
| { |
| struct gb_loopback *gb; |
| struct device *dev; |
| int retval; |
| char name[DEBUGFS_NAMELEN]; |
| unsigned long flags; |
| |
| gb = kzalloc(sizeof(*gb), GFP_KERNEL); |
| if (!gb) |
| return -ENOMEM; |
| |
| init_waitqueue_head(&gb->wq); |
| init_waitqueue_head(&gb->wq_completion); |
| atomic_set(&gb->outstanding_operations, 0); |
| gb_loopback_reset_stats(gb); |
| |
| /* Reported values to user-space for min/max timeouts */ |
| gb->timeout_min = jiffies_to_usecs(GB_LOOPBACK_TIMEOUT_MIN); |
| gb->timeout_max = jiffies_to_usecs(GB_LOOPBACK_TIMEOUT_MAX); |
| |
| if (!gb_dev.count) { |
| /* Calculate maximum payload */ |
| gb_dev.size_max = gb_operation_get_payload_size_max(connection); |
| if (gb_dev.size_max <= |
| sizeof(struct gb_loopback_transfer_request)) { |
| retval = -EINVAL; |
| goto out_kzalloc; |
| } |
| gb_dev.size_max -= sizeof(struct gb_loopback_transfer_request); |
| } |
| |
| /* Create per-connection sysfs and debugfs data-points */ |
| snprintf(name, sizeof(name), "raw_latency_%s", |
| dev_name(&connection->bundle->dev)); |
| gb->file = debugfs_create_file(name, S_IFREG | S_IRUGO, gb_dev.root, gb, |
| &gb_loopback_debugfs_latency_ops); |
| gb->connection = connection; |
| connection->private = gb; |
| |
| gb->id = ida_simple_get(&loopback_ida, 0, 0, GFP_KERNEL); |
| if (gb->id < 0) { |
| retval = gb->id; |
| goto out_ida; |
| } |
| |
| dev = device_create_with_groups(&loopback_class, |
| &connection->bundle->dev, |
| MKDEV(0, 0), gb, loopback_groups, |
| "gb_loopback%d", gb->id); |
| if (IS_ERR(dev)) { |
| retval = PTR_ERR(dev); |
| goto out_dev; |
| } |
| gb->dev = dev; |
| |
| /* Allocate kfifo */ |
| if (kfifo_alloc(&gb->kfifo_lat, kfifo_depth * sizeof(u32), |
| GFP_KERNEL)) { |
| retval = -ENOMEM; |
| goto out_conn; |
| } |
| if (kfifo_alloc(&gb->kfifo_ts, kfifo_depth * sizeof(struct timeval) * 2, |
| GFP_KERNEL)) { |
| retval = -ENOMEM; |
| goto out_kfifo0; |
| } |
| |
| /* Fork worker thread */ |
| mutex_init(&gb->mutex); |
| gb->task = kthread_run(gb_loopback_fn, gb, "gb_loopback"); |
| if (IS_ERR(gb->task)) { |
| retval = PTR_ERR(gb->task); |
| goto out_kfifo1; |
| } |
| |
| spin_lock_irqsave(&gb_dev.lock, flags); |
| gb_loopback_insert_id(gb); |
| gb_dev.count++; |
| spin_unlock_irqrestore(&gb_dev.lock, flags); |
| |
| gb_connection_latency_tag_enable(connection); |
| return 0; |
| |
| out_kfifo1: |
| kfifo_free(&gb->kfifo_ts); |
| out_kfifo0: |
| kfifo_free(&gb->kfifo_lat); |
| out_conn: |
| device_unregister(dev); |
| out_dev: |
| ida_simple_remove(&loopback_ida, gb->id); |
| out_ida: |
| debugfs_remove(gb->file); |
| out_kzalloc: |
| kfree(gb); |
| |
| return retval; |
| } |
| |
| static void gb_loopback_connection_exit(struct gb_connection *connection) |
| { |
| struct gb_loopback *gb = connection->private; |
| unsigned long flags; |
| |
| if (!IS_ERR_OR_NULL(gb->task)) |
| kthread_stop(gb->task); |
| |
| kfifo_free(&gb->kfifo_lat); |
| kfifo_free(&gb->kfifo_ts); |
| gb_connection_latency_tag_disable(connection); |
| debugfs_remove(gb->file); |
| gb_loopback_async_wait_all(gb); |
| |
| spin_lock_irqsave(&gb_dev.lock, flags); |
| gb_dev.count--; |
| list_del(&gb->entry); |
| spin_unlock_irqrestore(&gb_dev.lock, flags); |
| |
| device_unregister(gb->dev); |
| ida_simple_remove(&loopback_ida, gb->id); |
| |
| kfree(gb); |
| } |
| |
| static struct gb_protocol loopback_protocol = { |
| .name = "loopback", |
| .id = GREYBUS_PROTOCOL_LOOPBACK, |
| .major = GB_LOOPBACK_VERSION_MAJOR, |
| .minor = GB_LOOPBACK_VERSION_MINOR, |
| .connection_init = gb_loopback_connection_init, |
| .connection_exit = gb_loopback_connection_exit, |
| .request_recv = gb_loopback_request_recv, |
| }; |
| |
| static int loopback_init(void) |
| { |
| int retval; |
| |
| INIT_LIST_HEAD(&gb_dev.list); |
| INIT_LIST_HEAD(&gb_dev.list_op_async); |
| spin_lock_init(&gb_dev.lock); |
| gb_dev.root = debugfs_create_dir("gb_loopback", NULL); |
| |
| retval = class_register(&loopback_class); |
| if (retval) |
| goto err; |
| |
| retval = gb_protocol_register(&loopback_protocol); |
| if (retval) |
| goto err_unregister; |
| |
| return 0; |
| |
| err_unregister: |
| class_unregister(&loopback_class); |
| err: |
| debugfs_remove_recursive(gb_dev.root); |
| return retval; |
| } |
| module_init(loopback_init); |
| |
| static void __exit loopback_exit(void) |
| { |
| debugfs_remove_recursive(gb_dev.root); |
| gb_protocol_deregister(&loopback_protocol); |
| class_unregister(&loopback_class); |
| ida_destroy(&loopback_ida); |
| } |
| module_exit(loopback_exit); |
| |
| MODULE_LICENSE("GPL v2"); |