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v5.9
 
  1/*
  2 * Copyright 2020 Advanced Micro Devices, Inc.
  3 *
  4 * Permission is hereby granted, free of charge, to any person obtaining a
  5 * copy of this software and associated documentation files (the "Software"),
  6 * to deal in the Software without restriction, including without limitation
  7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  8 * and/or sell copies of the Software, and to permit persons to whom the
  9 * Software is furnished to do so, subject to the following conditions:
 10 *
 11 * The above copyright notice and this permission notice shall be included in
 12 * all copies or substantial portions of the Software.
 13 *
 14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 17 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
 18 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 19 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 20 * OTHER DEALINGS IN THE SOFTWARE.
 21 */
 22
 23#include <linux/poll.h>
 24#include <linux/wait.h>
 25#include <linux/anon_inodes.h>
 26#include <uapi/linux/kfd_ioctl.h>
 
 27#include "amdgpu_vm.h"
 28#include "kfd_priv.h"
 29#include "kfd_smi_events.h"
 
 30
 31struct kfd_smi_client {
 32	struct list_head list;
 33	struct kfifo fifo;
 34	wait_queue_head_t wait_queue;
 35	/* events enabled */
 36	uint64_t events;
 37	struct kfd_dev *dev;
 38	spinlock_t lock;
 
 
 
 39};
 40
 41#define MAX_KFIFO_SIZE	1024
 42
 43static __poll_t kfd_smi_ev_poll(struct file *, struct poll_table_struct *);
 44static ssize_t kfd_smi_ev_read(struct file *, char __user *, size_t, loff_t *);
 45static ssize_t kfd_smi_ev_write(struct file *, const char __user *, size_t,
 46				loff_t *);
 47static int kfd_smi_ev_release(struct inode *, struct file *);
 48
 49static const char kfd_smi_name[] = "kfd_smi_ev";
 50
 51static const struct file_operations kfd_smi_ev_fops = {
 52	.owner = THIS_MODULE,
 53	.poll = kfd_smi_ev_poll,
 54	.read = kfd_smi_ev_read,
 55	.write = kfd_smi_ev_write,
 56	.release = kfd_smi_ev_release
 57};
 58
 59static __poll_t kfd_smi_ev_poll(struct file *filep,
 60				struct poll_table_struct *wait)
 61{
 62	struct kfd_smi_client *client = filep->private_data;
 63	__poll_t mask = 0;
 64
 65	poll_wait(filep, &client->wait_queue, wait);
 66
 67	spin_lock(&client->lock);
 68	if (!kfifo_is_empty(&client->fifo))
 69		mask = EPOLLIN | EPOLLRDNORM;
 70	spin_unlock(&client->lock);
 71
 72	return mask;
 73}
 74
 75static ssize_t kfd_smi_ev_read(struct file *filep, char __user *user,
 76			       size_t size, loff_t *offset)
 77{
 78	int ret;
 79	size_t to_copy;
 80	struct kfd_smi_client *client = filep->private_data;
 81	unsigned char *buf;
 82
 83	buf = kmalloc(MAX_KFIFO_SIZE * sizeof(*buf), GFP_KERNEL);
 
 84	if (!buf)
 85		return -ENOMEM;
 86
 87	/* kfifo_to_user can sleep so we can't use spinlock protection around
 88	 * it. Instead, we kfifo out as spinlocked then copy them to the user.
 89	 */
 90	spin_lock(&client->lock);
 91	to_copy = kfifo_len(&client->fifo);
 92	if (!to_copy) {
 93		spin_unlock(&client->lock);
 94		ret = -EAGAIN;
 95		goto ret_err;
 96	}
 97	to_copy = min3(size, sizeof(buf), to_copy);
 98	ret = kfifo_out(&client->fifo, buf, to_copy);
 99	spin_unlock(&client->lock);
100	if (ret <= 0) {
101		ret = -EAGAIN;
102		goto ret_err;
103	}
104
105	ret = copy_to_user(user, buf, to_copy);
106	if (ret) {
107		ret = -EFAULT;
108		goto ret_err;
109	}
110
111	kfree(buf);
112	return to_copy;
113
114ret_err:
115	kfree(buf);
116	return ret;
117}
118
119static ssize_t kfd_smi_ev_write(struct file *filep, const char __user *user,
120				size_t size, loff_t *offset)
121{
122	struct kfd_smi_client *client = filep->private_data;
123	uint64_t events;
124
125	if (!access_ok(user, size) || size < sizeof(events))
126		return -EFAULT;
127	if (copy_from_user(&events, user, sizeof(events)))
128		return -EFAULT;
129
130	WRITE_ONCE(client->events, events);
131
132	return sizeof(events);
133}
134
 
 
 
 
 
 
 
 
135static int kfd_smi_ev_release(struct inode *inode, struct file *filep)
136{
137	struct kfd_smi_client *client = filep->private_data;
138	struct kfd_dev *dev = client->dev;
139
140	spin_lock(&dev->smi_lock);
141	list_del_rcu(&client->list);
142	spin_unlock(&dev->smi_lock);
143
144	synchronize_rcu();
145	kfifo_free(&client->fifo);
146	kfree(client);
147
148	return 0;
149}
150
151void kfd_smi_event_update_vmfault(struct kfd_dev *dev, uint16_t pasid)
 
152{
153	struct amdgpu_device *adev = (struct amdgpu_device *)dev->kgd;
154	struct amdgpu_task_info task_info;
155	/* VmFault msg = (hex)uint32_pid(8) + :(1) + task name(16) = 25 */
156	/* 16 bytes event + 1 byte space + 25 bytes msg + 1 byte \n = 43
157	 */
158	char fifo_in[43];
159	struct kfd_smi_client *client;
160	int len;
161
162	if (list_empty(&dev->smi_clients))
163		return;
164
165	memset(&task_info, 0, sizeof(struct amdgpu_task_info));
166	amdgpu_vm_get_task_info(adev, pasid, &task_info);
167	/* Report VM faults from user applications, not retry from kernel */
168	if (!task_info.pid)
169		return;
170
171	len = snprintf(fifo_in, 43, "%x %x:%s\n", KFD_SMI_EVENT_VMFAULT,
172		task_info.pid, task_info.task_name);
 
 
173
174	rcu_read_lock();
175
176	list_for_each_entry_rcu(client, &dev->smi_clients, list) {
177		if (!(READ_ONCE(client->events) & KFD_SMI_EVENT_VMFAULT))
178			continue;
179		spin_lock(&client->lock);
180		if (kfifo_avail(&client->fifo) >= len) {
181			kfifo_in(&client->fifo, fifo_in, len);
182			wake_up_all(&client->wait_queue);
 
 
 
183		}
184		else
185			pr_debug("smi_event(vmfault): no space left\n");
186		spin_unlock(&client->lock);
187	}
188
189	rcu_read_unlock();
190}
191
192int kfd_smi_event_open(struct kfd_dev *dev, uint32_t *fd)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
193{
194	struct kfd_smi_client *client;
195	int ret;
196
197	client = kzalloc(sizeof(struct kfd_smi_client), GFP_KERNEL);
198	if (!client)
199		return -ENOMEM;
200	INIT_LIST_HEAD(&client->list);
201
202	ret = kfifo_alloc(&client->fifo, MAX_KFIFO_SIZE, GFP_KERNEL);
203	if (ret) {
204		kfree(client);
205		return ret;
206	}
207
208	ret = anon_inode_getfd(kfd_smi_name, &kfd_smi_ev_fops, (void *)client,
209			       O_RDWR);
210	if (ret < 0) {
211		kfifo_free(&client->fifo);
212		kfree(client);
213		return ret;
214	}
215	*fd = ret;
216
217	init_waitqueue_head(&client->wait_queue);
218	spin_lock_init(&client->lock);
219	client->events = 0;
220	client->dev = dev;
 
 
221
222	spin_lock(&dev->smi_lock);
223	list_add_rcu(&client->list, &dev->smi_clients);
224	spin_unlock(&dev->smi_lock);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
225
226	return 0;
227}
v6.13.7
  1// SPDX-License-Identifier: GPL-2.0 OR MIT
  2/*
  3 * Copyright 2020-2022 Advanced Micro Devices, Inc.
  4 *
  5 * Permission is hereby granted, free of charge, to any person obtaining a
  6 * copy of this software and associated documentation files (the "Software"),
  7 * to deal in the Software without restriction, including without limitation
  8 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  9 * and/or sell copies of the Software, and to permit persons to whom the
 10 * Software is furnished to do so, subject to the following conditions:
 11 *
 12 * The above copyright notice and this permission notice shall be included in
 13 * all copies or substantial portions of the Software.
 14 *
 15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 18 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
 19 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 20 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 21 * OTHER DEALINGS IN THE SOFTWARE.
 22 */
 23
 24#include <linux/poll.h>
 25#include <linux/wait.h>
 26#include <linux/anon_inodes.h>
 27#include <uapi/linux/kfd_ioctl.h>
 28#include "amdgpu.h"
 29#include "amdgpu_vm.h"
 30#include "kfd_priv.h"
 31#include "kfd_smi_events.h"
 32#include "amdgpu_reset.h"
 33
 34struct kfd_smi_client {
 35	struct list_head list;
 36	struct kfifo fifo;
 37	wait_queue_head_t wait_queue;
 38	/* events enabled */
 39	uint64_t events;
 40	struct kfd_node *dev;
 41	spinlock_t lock;
 42	struct rcu_head rcu;
 43	pid_t pid;
 44	bool suser;
 45};
 46
 47#define KFD_MAX_KFIFO_SIZE	8192
 48
 49static __poll_t kfd_smi_ev_poll(struct file *, struct poll_table_struct *);
 50static ssize_t kfd_smi_ev_read(struct file *, char __user *, size_t, loff_t *);
 51static ssize_t kfd_smi_ev_write(struct file *, const char __user *, size_t,
 52				loff_t *);
 53static int kfd_smi_ev_release(struct inode *, struct file *);
 54
 55static const char kfd_smi_name[] = "kfd_smi_ev";
 56
 57static const struct file_operations kfd_smi_ev_fops = {
 58	.owner = THIS_MODULE,
 59	.poll = kfd_smi_ev_poll,
 60	.read = kfd_smi_ev_read,
 61	.write = kfd_smi_ev_write,
 62	.release = kfd_smi_ev_release
 63};
 64
 65static __poll_t kfd_smi_ev_poll(struct file *filep,
 66				struct poll_table_struct *wait)
 67{
 68	struct kfd_smi_client *client = filep->private_data;
 69	__poll_t mask = 0;
 70
 71	poll_wait(filep, &client->wait_queue, wait);
 72
 73	spin_lock(&client->lock);
 74	if (!kfifo_is_empty(&client->fifo))
 75		mask = EPOLLIN | EPOLLRDNORM;
 76	spin_unlock(&client->lock);
 77
 78	return mask;
 79}
 80
 81static ssize_t kfd_smi_ev_read(struct file *filep, char __user *user,
 82			       size_t size, loff_t *offset)
 83{
 84	int ret;
 85	size_t to_copy;
 86	struct kfd_smi_client *client = filep->private_data;
 87	unsigned char *buf;
 88
 89	size = min_t(size_t, size, KFD_MAX_KFIFO_SIZE);
 90	buf = kmalloc(size, GFP_KERNEL);
 91	if (!buf)
 92		return -ENOMEM;
 93
 94	/* kfifo_to_user can sleep so we can't use spinlock protection around
 95	 * it. Instead, we kfifo out as spinlocked then copy them to the user.
 96	 */
 97	spin_lock(&client->lock);
 98	to_copy = kfifo_len(&client->fifo);
 99	if (!to_copy) {
100		spin_unlock(&client->lock);
101		ret = -EAGAIN;
102		goto ret_err;
103	}
104	to_copy = min(size, to_copy);
105	ret = kfifo_out(&client->fifo, buf, to_copy);
106	spin_unlock(&client->lock);
107	if (ret <= 0) {
108		ret = -EAGAIN;
109		goto ret_err;
110	}
111
112	ret = copy_to_user(user, buf, to_copy);
113	if (ret) {
114		ret = -EFAULT;
115		goto ret_err;
116	}
117
118	kfree(buf);
119	return to_copy;
120
121ret_err:
122	kfree(buf);
123	return ret;
124}
125
126static ssize_t kfd_smi_ev_write(struct file *filep, const char __user *user,
127				size_t size, loff_t *offset)
128{
129	struct kfd_smi_client *client = filep->private_data;
130	uint64_t events;
131
132	if (!access_ok(user, size) || size < sizeof(events))
133		return -EFAULT;
134	if (copy_from_user(&events, user, sizeof(events)))
135		return -EFAULT;
136
137	WRITE_ONCE(client->events, events);
138
139	return sizeof(events);
140}
141
142static void kfd_smi_ev_client_free(struct rcu_head *p)
143{
144	struct kfd_smi_client *ev = container_of(p, struct kfd_smi_client, rcu);
145
146	kfifo_free(&ev->fifo);
147	kfree(ev);
148}
149
150static int kfd_smi_ev_release(struct inode *inode, struct file *filep)
151{
152	struct kfd_smi_client *client = filep->private_data;
153	struct kfd_node *dev = client->dev;
154
155	spin_lock(&dev->smi_lock);
156	list_del_rcu(&client->list);
157	spin_unlock(&dev->smi_lock);
158
159	call_rcu(&client->rcu, kfd_smi_ev_client_free);
 
 
 
160	return 0;
161}
162
163static bool kfd_smi_ev_enabled(pid_t pid, struct kfd_smi_client *client,
164			       unsigned int event)
165{
166	uint64_t all = KFD_SMI_EVENT_MASK_FROM_INDEX(KFD_SMI_EVENT_ALL_PROCESS);
167	uint64_t events = READ_ONCE(client->events);
 
 
 
 
 
 
168
169	if (pid && client->pid != pid && !(client->suser && (events & all)))
170		return false;
171
172	return events & KFD_SMI_EVENT_MASK_FROM_INDEX(event);
173}
 
 
 
174
175static void add_event_to_kfifo(pid_t pid, struct kfd_node *dev,
176			       unsigned int smi_event, char *event_msg, int len)
177{
178	struct kfd_smi_client *client;
179
180	rcu_read_lock();
181
182	list_for_each_entry_rcu(client, &dev->smi_clients, list) {
183		if (!kfd_smi_ev_enabled(pid, client, smi_event))
184			continue;
185		spin_lock(&client->lock);
186		if (kfifo_avail(&client->fifo) >= len) {
187			kfifo_in(&client->fifo, event_msg, len);
188			wake_up_all(&client->wait_queue);
189		} else {
190			pr_debug("smi_event(EventID: %u): no space left\n",
191					smi_event);
192		}
 
 
193		spin_unlock(&client->lock);
194	}
195
196	rcu_read_unlock();
197}
198
199__printf(4, 5)
200static void kfd_smi_event_add(pid_t pid, struct kfd_node *dev,
201			      unsigned int event, char *fmt, ...)
202{
203	char fifo_in[KFD_SMI_EVENT_MSG_SIZE];
204	int len;
205	va_list args;
206
207	if (list_empty(&dev->smi_clients))
208		return;
209
210	len = snprintf(fifo_in, sizeof(fifo_in), "%x ", event);
211
212	va_start(args, fmt);
213	len += vsnprintf(fifo_in + len, sizeof(fifo_in) - len, fmt, args);
214	va_end(args);
215
216	add_event_to_kfifo(pid, dev, event, fifo_in, len);
217}
218
219void kfd_smi_event_update_gpu_reset(struct kfd_node *dev, bool post_reset,
220				    struct amdgpu_reset_context *reset_context)
221{
222	unsigned int event;
223	char reset_cause[64];
224
225	if (post_reset) {
226		event = KFD_SMI_EVENT_GPU_POST_RESET;
227	} else {
228		event = KFD_SMI_EVENT_GPU_PRE_RESET;
229		++(dev->reset_seq_num);
230	}
231
232	memset(reset_cause, 0, sizeof(reset_cause));
233
234	if (reset_context)
235		amdgpu_reset_get_desc(reset_context, reset_cause,
236				      sizeof(reset_cause));
237
238	kfd_smi_event_add(0, dev, event, KFD_EVENT_FMT_UPDATE_GPU_RESET(
239			  dev->reset_seq_num, reset_cause));
240}
241
242void kfd_smi_event_update_thermal_throttling(struct kfd_node *dev,
243					     uint64_t throttle_bitmask)
244{
245	kfd_smi_event_add(0, dev, KFD_SMI_EVENT_THERMAL_THROTTLE, KFD_EVENT_FMT_THERMAL_THROTTLING(
246			  throttle_bitmask,
247			  amdgpu_dpm_get_thermal_throttling_counter(dev->adev)));
248}
249
250void kfd_smi_event_update_vmfault(struct kfd_node *dev, uint16_t pasid)
251{
252	struct amdgpu_task_info *task_info;
253
254	task_info = amdgpu_vm_get_task_info_pasid(dev->adev, pasid);
255	if (task_info) {
256		/* Report VM faults from user applications, not retry from kernel */
257		if (task_info->pid)
258			kfd_smi_event_add(0, dev, KFD_SMI_EVENT_VMFAULT, KFD_EVENT_FMT_VMFAULT(
259					  task_info->pid, task_info->task_name));
260		amdgpu_vm_put_task_info(task_info);
261	}
262}
263
264void kfd_smi_event_page_fault_start(struct kfd_node *node, pid_t pid,
265				    unsigned long address, bool write_fault,
266				    ktime_t ts)
267{
268	kfd_smi_event_add(pid, node, KFD_SMI_EVENT_PAGE_FAULT_START,
269			  KFD_EVENT_FMT_PAGEFAULT_START(ktime_to_ns(ts), pid,
270			  address, node->id, write_fault ? 'W' : 'R'));
271}
272
273void kfd_smi_event_page_fault_end(struct kfd_node *node, pid_t pid,
274				  unsigned long address, bool migration)
275{
276	kfd_smi_event_add(pid, node, KFD_SMI_EVENT_PAGE_FAULT_END,
277			  KFD_EVENT_FMT_PAGEFAULT_END(ktime_get_boottime_ns(),
278			  pid, address, node->id, migration ? 'M' : 'U'));
279}
280
281void kfd_smi_event_migration_start(struct kfd_node *node, pid_t pid,
282				   unsigned long start, unsigned long end,
283				   uint32_t from, uint32_t to,
284				   uint32_t prefetch_loc, uint32_t preferred_loc,
285				   uint32_t trigger)
286{
287	kfd_smi_event_add(pid, node, KFD_SMI_EVENT_MIGRATE_START,
288			  KFD_EVENT_FMT_MIGRATE_START(
289			  ktime_get_boottime_ns(), pid, start, end - start,
290			  from, to, prefetch_loc, preferred_loc, trigger));
291}
292
293void kfd_smi_event_migration_end(struct kfd_node *node, pid_t pid,
294				 unsigned long start, unsigned long end,
295				 uint32_t from, uint32_t to, uint32_t trigger,
296				 int error_code)
297{
298	kfd_smi_event_add(pid, node, KFD_SMI_EVENT_MIGRATE_END,
299			  KFD_EVENT_FMT_MIGRATE_END(
300			  ktime_get_boottime_ns(), pid, start, end - start,
301			  from, to, trigger, error_code));
302}
303
304void kfd_smi_event_queue_eviction(struct kfd_node *node, pid_t pid,
305				  uint32_t trigger)
306{
307	kfd_smi_event_add(pid, node, KFD_SMI_EVENT_QUEUE_EVICTION,
308			  KFD_EVENT_FMT_QUEUE_EVICTION(ktime_get_boottime_ns(), pid,
309			  node->id, trigger));
310}
311
312void kfd_smi_event_queue_restore(struct kfd_node *node, pid_t pid)
313{
314	kfd_smi_event_add(pid, node, KFD_SMI_EVENT_QUEUE_RESTORE,
315			  KFD_EVENT_FMT_QUEUE_RESTORE(ktime_get_boottime_ns(), pid,
316			  node->id, 0));
317}
318
319void kfd_smi_event_queue_restore_rescheduled(struct mm_struct *mm)
320{
321	struct kfd_process *p;
322	int i;
323
324	p = kfd_lookup_process_by_mm(mm);
325	if (!p)
326		return;
327
328	for (i = 0; i < p->n_pdds; i++) {
329		struct kfd_process_device *pdd = p->pdds[i];
330
331		kfd_smi_event_add(p->lead_thread->pid, pdd->dev,
332				  KFD_SMI_EVENT_QUEUE_RESTORE,
333				  KFD_EVENT_FMT_QUEUE_RESTORE(ktime_get_boottime_ns(),
334				  p->lead_thread->pid, pdd->dev->id, 'R'));
335	}
336	kfd_unref_process(p);
337}
338
339void kfd_smi_event_unmap_from_gpu(struct kfd_node *node, pid_t pid,
340				  unsigned long address, unsigned long last,
341				  uint32_t trigger)
342{
343	kfd_smi_event_add(pid, node, KFD_SMI_EVENT_UNMAP_FROM_GPU,
344			  KFD_EVENT_FMT_UNMAP_FROM_GPU(ktime_get_boottime_ns(),
345			  pid, address, last - address + 1, node->id, trigger));
346}
347
348int kfd_smi_event_open(struct kfd_node *dev, uint32_t *fd)
349{
350	struct kfd_smi_client *client;
351	int ret;
352
353	client = kzalloc(sizeof(struct kfd_smi_client), GFP_KERNEL);
354	if (!client)
355		return -ENOMEM;
356	INIT_LIST_HEAD(&client->list);
357
358	ret = kfifo_alloc(&client->fifo, KFD_MAX_KFIFO_SIZE, GFP_KERNEL);
359	if (ret) {
360		kfree(client);
361		return ret;
362	}
363
 
 
 
 
 
 
 
 
 
364	init_waitqueue_head(&client->wait_queue);
365	spin_lock_init(&client->lock);
366	client->events = 0;
367	client->dev = dev;
368	client->pid = current->tgid;
369	client->suser = capable(CAP_SYS_ADMIN);
370
371	spin_lock(&dev->smi_lock);
372	list_add_rcu(&client->list, &dev->smi_clients);
373	spin_unlock(&dev->smi_lock);
374
375	ret = anon_inode_getfd(kfd_smi_name, &kfd_smi_ev_fops, (void *)client,
376			       O_RDWR);
377	if (ret < 0) {
378		spin_lock(&dev->smi_lock);
379		list_del_rcu(&client->list);
380		spin_unlock(&dev->smi_lock);
381
382		synchronize_rcu();
383
384		kfifo_free(&client->fifo);
385		kfree(client);
386		return ret;
387	}
388	*fd = ret;
389
390	return 0;
391}