1 // SPDX-License-Identifier: GPL-2.0
5  * Pseudo-locking support built on top of Cache Allocation Technology (CAT)
26 #include <asm/intel-family.h>
44  * pseudo-locked regions.
51  * get_prefetch_disable_bits - prefetch disable bits of supported platforms
54  * pseudo-locking. This includes testing to ensure pseudo-locked regions
56  * as well as that these pseudo-locked regions can maintain their low cache
59  * After a platform has been validated to support pseudo-locking its
105  * pseudo_lock_minor_get - Obtain available minor number
120 		return -ENOSPC;  in pseudo_lock_minor_get()
129  * pseudo_lock_minor_release - Return minor number to available
138  * region_find_by_minor - Locate a pseudo-lock region by inode minor number
139  * @minor: The minor number of the device representing pseudo-locked region
142  * pseudo-locked region it belongs to. This is done by matching the minor
143  * number of the device to the pseudo-locked region it belongs.
145  * Minor numbers are assigned at the time a pseudo-locked region is associated
148  * Return: On success return pointer to resource group owning the pseudo-locked
156 		if (rdtgrp->plr && rdtgrp->plr->minor == minor) {  in region_find_by_minor()
165  * pseudo_lock_pm_req - A power management QoS request list entry
166  * @list:	Entry within the @pm_reqs list for a pseudo-locked region
178 	list_for_each_entry_safe(pm_req, next, &plr->pm_reqs, list) {  in pseudo_lock_cstates_relax()
179 		dev_pm_qos_remove_request(&pm_req->req);  in pseudo_lock_cstates_relax()
180 		list_del(&pm_req->list);  in pseudo_lock_cstates_relax()
186  * pseudo_lock_cstates_constrain - Restrict cores from entering C6
206 	for_each_cpu(cpu, &plr->d->cpu_mask) {  in pseudo_lock_cstates_constrain()
210 			ret = -ENOMEM;  in pseudo_lock_cstates_constrain()
214 					     &pm_req->req,  in pseudo_lock_cstates_constrain()
221 			ret = -1;  in pseudo_lock_cstates_constrain()
224 		list_add(&pm_req->list, &plr->pm_reqs);  in pseudo_lock_cstates_constrain()
235  * pseudo_lock_region_clear - Reset pseudo-lock region data
236  * @plr: pseudo-lock region
238  * All content of the pseudo-locked region is reset - any memory allocated
245 	plr->size = 0;  in pseudo_lock_region_clear()
246 	plr->line_size = 0;  in pseudo_lock_region_clear()
247 	kfree(plr->kmem);  in pseudo_lock_region_clear()
248 	plr->kmem = NULL;  in pseudo_lock_region_clear()
249 	plr->r = NULL;  in pseudo_lock_region_clear()
250 	if (plr->d)  in pseudo_lock_region_clear()
251 		plr->d->plr = NULL;  in pseudo_lock_region_clear()
252 	plr->d = NULL;  in pseudo_lock_region_clear()
253 	plr->cbm = 0;  in pseudo_lock_region_clear()
254 	plr->debugfs_dir = NULL;  in pseudo_lock_region_clear()
258  * pseudo_lock_region_init - Initialize pseudo-lock region information
259  * @plr: pseudo-lock region
261  * Called after user provided a schemata to be pseudo-locked. From the
264  * required for pseudo-locking is deduced from this data and &struct
266  * - size in bytes of the region to be pseudo-locked
267  * - cache line size to know the stride with which data needs to be accessed
268  *   to be pseudo-locked
269  * - a cpu associated with the cache instance on which the pseudo-locking
272  * Return: 0 on success, <0 on failure. Descriptive error will be written
282 	plr->cpu = cpumask_first(&plr->d->cpu_mask);  in pseudo_lock_region_init()
284 	if (!cpu_online(plr->cpu)) {  in pseudo_lock_region_init()
286 				    plr->cpu);  in pseudo_lock_region_init()
287 		ret = -ENODEV;  in pseudo_lock_region_init()
291 	ci = get_cpu_cacheinfo(plr->cpu);  in pseudo_lock_region_init()
293 	plr->size = rdtgroup_cbm_to_size(plr->r, plr->d, plr->cbm);  in pseudo_lock_region_init()
295 	for (i = 0; i < ci->num_leaves; i++) {  in pseudo_lock_region_init()
296 		if (ci->info_list[i].level == plr->r->cache_level) {  in pseudo_lock_region_init()
297 			plr->line_size = ci->info_list[i].coherency_line_size;  in pseudo_lock_region_init()
302 	ret = -1;  in pseudo_lock_region_init()
310  * pseudo_lock_init - Initialize a pseudo-lock region
311  * @rdtgrp: resource group to which new pseudo-locked region will belong
313  * A pseudo-locked region is associated with a resource group. When this
314  * association is created the pseudo-locked region is initialized. The
315  * details of the pseudo-locked region are not known at this time so only
326 		return -ENOMEM;  in pseudo_lock_init()
328 	init_waitqueue_head(&plr->lock_thread_wq);  in pseudo_lock_init()
329 	INIT_LIST_HEAD(&plr->pm_reqs);  in pseudo_lock_init()
330 	rdtgrp->plr = plr;  in pseudo_lock_init()
335  * pseudo_lock_region_alloc - Allocate kernel memory that will be pseudo-locked
336  * @plr: pseudo-lock region
338  * Initialize the details required to set up the pseudo-locked region and
339  * allocate the contiguous memory that will be pseudo-locked to the cache.
341  * Return: 0 on success, <0 on failure.  Descriptive error will be written
356 	if (plr->size > KMALLOC_MAX_SIZE) {  in pseudo_lock_region_alloc()
358 		ret = -E2BIG;  in pseudo_lock_region_alloc()
362 	plr->kmem = kzalloc(plr->size, GFP_KERNEL);  in pseudo_lock_region_alloc()
363 	if (!plr->kmem) {  in pseudo_lock_region_alloc()
365 		ret = -ENOMEM;  in pseudo_lock_region_alloc()
378  * pseudo_lock_free - Free a pseudo-locked region
379  * @rdtgrp: resource group to which pseudo-locked region belonged
381  * The pseudo-locked region's resources have already been released, or not
389 	pseudo_lock_region_clear(rdtgrp->plr);  in pseudo_lock_free()
390 	kfree(rdtgrp->plr);  in pseudo_lock_free()
391 	rdtgrp->plr = NULL;  in pseudo_lock_free()
395  * pseudo_lock_fn - Load kernel memory into cache
396  * @_rdtgrp: resource group to which pseudo-lock region belongs
398  * This is the core pseudo-locking flow.
403  * with class of service set to the bitmask of the pseudo-locked region.
416 	struct pseudo_lock_region *plr = rdtgrp->plr;  in pseudo_lock_fn()
426 	 * pseudo-locking success rate when KASAN is active.  in pseudo_lock_fn()
439 	 * will get a cache hit in below loop from outside of pseudo-locked  in pseudo_lock_fn()
458 	 * being pseudo-locked is reached the hardware will not read beyond  in pseudo_lock_fn()
459 	 * the buffer and evict pseudo-locked memory read earlier from the  in pseudo_lock_fn()
465 	mem_r = plr->kmem;  in pseudo_lock_fn()
466 	size = plr->size;  in pseudo_lock_fn()
467 	line_size = plr->line_size;  in pseudo_lock_fn()
471 	 * pseudo-locked followed by reading of kernel memory to load it  in pseudo_lock_fn()
474 	__wrmsr(IA32_PQR_ASSOC, rmid_p, rdtgrp->closid);  in pseudo_lock_fn()
477 	 * into cache region associated with just activated plr->closid.  in pseudo_lock_fn()
479 	 * - In first loop the cache region is shared with the page walker  in pseudo_lock_fn()
481 	 * - In the second loop the paging structure caches are used and  in pseudo_lock_fn()
508 	 * does not overlap with pseudo-locked region.  in pseudo_lock_fn()
512 	/* Re-enable the hardware prefetcher(s) */  in pseudo_lock_fn()
516 	plr->thread_done = 1;  in pseudo_lock_fn()
517 	wake_up_interruptible(&plr->lock_thread_wq);  in pseudo_lock_fn()
522  * rdtgroup_monitor_in_progress - Test if monitoring in progress
530 	return !list_empty(&rdtgrp->mon.crdtgrp_list);  in rdtgroup_monitor_in_progress()
534  * rdtgroup_locksetup_user_restrict - Restrict user access to group
537  * A resource group used for cache pseudo-locking cannot have cpus or tasks
584  * rdtgroup_locksetup_user_restore - Restore user access to group
631  * rdtgroup_locksetup_enter - Resource group enters locksetup mode
635  * to represent a pseudo-locked region and is in the process of being set
636  * up to do so. A resource group used for a pseudo-locked region would
639  * future. Monitoring of a pseudo-locked region is not allowed either.
641  * The above and more restrictions on a pseudo-locked region are checked
657 		rdt_last_cmd_puts("Cannot pseudo-lock default group\n");  in rdtgroup_locksetup_enter()
658 		return -EINVAL;  in rdtgroup_locksetup_enter()
662 	 * Cache Pseudo-locking not supported when CDP is enabled.  in rdtgroup_locksetup_enter()
666 	 * - When CDP is enabled two separate resources are exposed,  in rdtgroup_locksetup_enter()
668 	 *   The implication for pseudo-locking is that if a  in rdtgroup_locksetup_enter()
669 	 *   pseudo-locked region is created on a domain of one  in rdtgroup_locksetup_enter()
670 	 *   resource (eg. L3CODE), then a pseudo-locked region cannot  in rdtgroup_locksetup_enter()
673 	 *   pseudo-locked region involves a call to wbinvd that will  in rdtgroup_locksetup_enter()
675 	 * - Considering the previous, it may be possible to only  in rdtgroup_locksetup_enter()
676 	 *   expose one of the CDP resources to pseudo-locking and  in rdtgroup_locksetup_enter()
680 	 * - If only one region is exposed to pseudo-locking we should  in rdtgroup_locksetup_enter()
682 	 *   for pseudo-locking should take into account both resources.  in rdtgroup_locksetup_enter()
683 	 *   Similarly, if a pseudo-locked region is created in one  in rdtgroup_locksetup_enter()
690 		return -EINVAL;  in rdtgroup_locksetup_enter()
695 	 * platform does not support Cache Pseudo-Locking.  in rdtgroup_locksetup_enter()
699 		rdt_last_cmd_puts("Pseudo-locking not supported\n");  in rdtgroup_locksetup_enter()
700 		return -EINVAL;  in rdtgroup_locksetup_enter()
705 		return -EINVAL;  in rdtgroup_locksetup_enter()
710 		return -EINVAL;  in rdtgroup_locksetup_enter()
713 	if (!cpumask_empty(&rdtgrp->cpu_mask)) {  in rdtgroup_locksetup_enter()
715 		return -EINVAL;  in rdtgroup_locksetup_enter()
720 		return -EIO;  in rdtgroup_locksetup_enter()
725 		rdt_last_cmd_puts("Unable to init pseudo-lock region\n");  in rdtgroup_locksetup_enter()
732 	 * anymore when this group would be used for pseudo-locking. This  in rdtgroup_locksetup_enter()
735 	free_rmid(rdtgrp->mon.rmid);  in rdtgroup_locksetup_enter()
747  * rdtgroup_locksetup_exit - resource group exist locksetup mode
765 		rdtgrp->mon.rmid = ret;  in rdtgroup_locksetup_exit()
770 		free_rmid(rdtgrp->mon.rmid);  in rdtgroup_locksetup_exit()
779  * rdtgroup_cbm_overlaps_pseudo_locked - Test if CBM or portion is pseudo-locked
785  * pseudo-locked region on @d.
790  * Return: true if @cbm overlaps with pseudo-locked region on @d, false
798 	if (d->plr) {  in rdtgroup_cbm_overlaps_pseudo_locked()
799 		cbm_len = d->plr->r->cache.cbm_len;  in rdtgroup_cbm_overlaps_pseudo_locked()
800 		cbm_b = d->plr->cbm;  in rdtgroup_cbm_overlaps_pseudo_locked()
808  * rdtgroup_pseudo_locked_in_hierarchy - Pseudo-locked region in cache hierarchy
811  * The setup of a pseudo-locked region affects all cache instances within
813  * pseudo-locked regions exist within a cache hierarchy to prevent any
814  * attempts to create new pseudo-locked regions in the same hierarchy.
816  * Return: true if a pseudo-locked region exists in the hierarchy of @d or
831 	 * First determine which cpus have pseudo-locked regions  in rdtgroup_pseudo_locked_in_hierarchy()
835 		list_for_each_entry(d_i, &r->domains, list) {  in rdtgroup_pseudo_locked_in_hierarchy()
836 			if (d_i->plr)  in rdtgroup_pseudo_locked_in_hierarchy()
838 					   &d_i->cpu_mask);  in rdtgroup_pseudo_locked_in_hierarchy()
843 	 * Next test if new pseudo-locked region would intersect with  in rdtgroup_pseudo_locked_in_hierarchy()
846 	if (cpumask_intersects(&d->cpu_mask, cpu_with_psl))  in rdtgroup_pseudo_locked_in_hierarchy()
854  * measure_cycles_lat_fn - Measure cycle latency to read pseudo-locked memory
855  * @_plr: pseudo-lock region to measure
879 	mem_r = READ_ONCE(plr->kmem);  in measure_cycles_lat_fn()
885 	for (i = 0; i < plr->size; i += 32) {  in measure_cycles_lat_fn()
892 		trace_pseudo_lock_mem_latency((u32)(end - start));  in measure_cycles_lat_fn()
896 	plr->thread_done = 1;  in measure_cycles_lat_fn()
897 	wake_up_interruptible(&plr->lock_thread_wq);  in measure_cycles_lat_fn()
945 	miss_event = perf_event_create_kernel_counter(miss_attr, plr->cpu,  in measure_residency_fn()
950 	hit_event = perf_event_create_kernel_counter(hit_attr, plr->cpu,  in measure_residency_fn()
977 	 * interrupts disabled - it is thus safe to read the counter index.  in measure_residency_fn()
981 	line_size = READ_ONCE(plr->line_size);  in measure_residency_fn()
982 	mem_r = READ_ONCE(plr->kmem);  in measure_residency_fn()
983 	size = READ_ONCE(plr->size);  in measure_residency_fn()
986 	 * Read counter variables twice - first to load the instructions  in measure_residency_fn()
993 	 * From SDM: Performing back-to-back fast reads are not guaranteed  in measure_residency_fn()
1029 	/* Re-enable hardware prefetchers */  in measure_residency_fn()
1040 	counts->miss_before = miss_before;  in measure_residency_fn()
1041 	counts->hits_before = hits_before;  in measure_residency_fn()
1042 	counts->miss_after  = miss_after;  in measure_residency_fn()
1043 	counts->hits_after  = hits_after;  in measure_residency_fn()
1053 	 * Non-architectural event for the Goldmont Microarchitecture  in measure_l2_residency()
1077 	trace_pseudo_lock_l2(counts.hits_after - counts.hits_before,  in measure_l2_residency()
1078 			     counts.miss_after - counts.miss_before);  in measure_l2_residency()
1080 	plr->thread_done = 1;  in measure_l2_residency()
1081 	wake_up_interruptible(&plr->lock_thread_wq);  in measure_l2_residency()
1117 	counts.miss_after -= counts.miss_before;  in measure_l3_residency()
1127 		counts.hits_after -= counts.hits_before;  in measure_l3_residency()
1129 		counts.hits_after -= min(counts.miss_after, counts.hits_after);  in measure_l3_residency()
1131 		counts.hits_after -= counts.hits_before;  in measure_l3_residency()
1136 	plr->thread_done = 1;  in measure_l3_residency()
1137 	wake_up_interruptible(&plr->lock_thread_wq);  in measure_l3_residency()
1142  * pseudo_lock_measure_cycles - Trigger latency measure to pseudo-locked region
1144  * The measurement of latency to access a pseudo-locked region should be
1145  * done from a cpu that is associated with that pseudo-locked region.
1153 	struct pseudo_lock_region *plr = rdtgrp->plr;  in pseudo_lock_measure_cycles()
1156 	int ret = -1;  in pseudo_lock_measure_cycles()
1161 	if (rdtgrp->flags & RDT_DELETED) {  in pseudo_lock_measure_cycles()
1162 		ret = -ENODEV;  in pseudo_lock_measure_cycles()
1166 	if (!plr->d) {  in pseudo_lock_measure_cycles()
1167 		ret = -ENODEV;  in pseudo_lock_measure_cycles()
1171 	plr->thread_done = 0;  in pseudo_lock_measure_cycles()
1172 	cpu = cpumask_first(&plr->d->cpu_mask);  in pseudo_lock_measure_cycles()
1174 		ret = -ENODEV;  in pseudo_lock_measure_cycles()
1178 	plr->cpu = cpu;  in pseudo_lock_measure_cycles()
1205 	ret = wait_event_interruptible(plr->lock_thread_wq,  in pseudo_lock_measure_cycles()
1206 				       plr->thread_done == 1);  in pseudo_lock_measure_cycles()
1222 	struct rdtgroup *rdtgrp = file->private_data;  in pseudo_lock_measure_trigger()
1228 	buf_size = min(count, (sizeof(buf) - 1));  in pseudo_lock_measure_trigger()
1230 		return -EFAULT;  in pseudo_lock_measure_trigger()
1236 			return -EINVAL;  in pseudo_lock_measure_trigger()
1237 		ret = debugfs_file_get(file->f_path.dentry);  in pseudo_lock_measure_trigger()
1243 		debugfs_file_put(file->f_path.dentry);  in pseudo_lock_measure_trigger()
1256  * rdtgroup_pseudo_lock_create - Create a pseudo-locked region
1257  * @rdtgrp: resource group to which pseudo-lock region belongs
1259  * Called when a resource group in the pseudo-locksetup mode receives a
1260  * valid schemata that should be pseudo-locked. Since the resource group is
1261  * in pseudo-locksetup mode the &struct pseudo_lock_region has already been
1263  * occurs the resource group remains in the pseudo-locksetup mode with the
1265  * information and ready for the user to re-attempt pseudo-locking by
1268  * Return: 0 if the pseudo-locked region was successfully pseudo-locked, <0
1269  * on failure. Descriptive error will be written to last_cmd_status buffer.
1273 	struct pseudo_lock_region *plr = rdtgrp->plr;  in rdtgroup_pseudo_lock_create()
1285 		ret = -EINVAL;  in rdtgroup_pseudo_lock_create()
1289 	plr->thread_done = 0;  in rdtgroup_pseudo_lock_create()
1292 					cpu_to_node(plr->cpu),  in rdtgroup_pseudo_lock_create()
1293 					"pseudo_lock/%u", plr->cpu);  in rdtgroup_pseudo_lock_create()
1300 	kthread_bind(thread, plr->cpu);  in rdtgroup_pseudo_lock_create()
1303 	ret = wait_event_interruptible(plr->lock_thread_wq,  in rdtgroup_pseudo_lock_create()
1304 				       plr->thread_done == 1);  in rdtgroup_pseudo_lock_create()
1312 		 * empty pseudo-locking loop.  in rdtgroup_pseudo_lock_create()
1326 	 * pseudo-locked region will still be here on return.  in rdtgroup_pseudo_lock_create()
1329 	 * deadlock with the mm->mmap_lock which is obtained in the  in rdtgroup_pseudo_lock_create()
1336 		plr->debugfs_dir = debugfs_create_dir(rdtgrp->kn->name,  in rdtgroup_pseudo_lock_create()
1338 		if (!IS_ERR_OR_NULL(plr->debugfs_dir))  in rdtgroup_pseudo_lock_create()
1340 					    plr->debugfs_dir, rdtgrp,  in rdtgroup_pseudo_lock_create()
1346 			    rdtgrp, "%s", rdtgrp->kn->name);  in rdtgroup_pseudo_lock_create()
1357 	/* We released the mutex - check if group was removed while we did so */  in rdtgroup_pseudo_lock_create()
1358 	if (rdtgrp->flags & RDT_DELETED) {  in rdtgroup_pseudo_lock_create()
1359 		ret = -ENODEV;  in rdtgroup_pseudo_lock_create()
1363 	plr->minor = new_minor;  in rdtgroup_pseudo_lock_create()
1365 	rdtgrp->mode = RDT_MODE_PSEUDO_LOCKED;  in rdtgroup_pseudo_lock_create()
1366 	closid_free(rdtgrp->closid);  in rdtgroup_pseudo_lock_create()
1376 	debugfs_remove_recursive(plr->debugfs_dir);  in rdtgroup_pseudo_lock_create()
1387  * rdtgroup_pseudo_lock_remove - Remove a pseudo-locked region
1388  * @rdtgrp: resource group to which the pseudo-locked region belongs
1390  * The removal of a pseudo-locked region can be initiated when the resource
1393  * not go back to pseudo-locksetup mode before it is removed, instead it is
1402 	struct pseudo_lock_region *plr = rdtgrp->plr;  in rdtgroup_pseudo_lock_remove()
1404 	if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP) {  in rdtgroup_pseudo_lock_remove()
1406 		 * Default group cannot be a pseudo-locked region so we can  in rdtgroup_pseudo_lock_remove()
1409 		closid_free(rdtgrp->closid);  in rdtgroup_pseudo_lock_remove()
1414 	debugfs_remove_recursive(rdtgrp->plr->debugfs_dir);  in rdtgroup_pseudo_lock_remove()
1415 	device_destroy(pseudo_lock_class, MKDEV(pseudo_lock_major, plr->minor));  in rdtgroup_pseudo_lock_remove()
1416 	pseudo_lock_minor_release(plr->minor);  in rdtgroup_pseudo_lock_remove()
1431 		return -ENODEV;  in pseudo_lock_dev_open()
1434 	filp->private_data = rdtgrp;  in pseudo_lock_dev_open()
1435 	atomic_inc(&rdtgrp->waitcount);  in pseudo_lock_dev_open()
1436 	/* Perform a non-seekable open - llseek is not supported */  in pseudo_lock_dev_open()
1437 	filp->f_mode &= ~(FMODE_LSEEK | FMODE_PREAD | FMODE_PWRITE);  in pseudo_lock_dev_open()
1449 	rdtgrp = filp->private_data;  in pseudo_lock_dev_release()
1453 		return -ENODEV;  in pseudo_lock_dev_release()
1455 	filp->private_data = NULL;  in pseudo_lock_dev_release()
1456 	atomic_dec(&rdtgrp->waitcount);  in pseudo_lock_dev_release()
1464 	return -EINVAL;  in pseudo_lock_dev_mremap()
1473 	unsigned long vsize = vma->vm_end - vma->vm_start;  in pseudo_lock_dev_mmap()
1474 	unsigned long off = vma->vm_pgoff << PAGE_SHIFT;  in pseudo_lock_dev_mmap()
1482 	rdtgrp = filp->private_data;  in pseudo_lock_dev_mmap()
1486 		return -ENODEV;  in pseudo_lock_dev_mmap()
1489 	plr = rdtgrp->plr;  in pseudo_lock_dev_mmap()
1491 	if (!plr->d) {  in pseudo_lock_dev_mmap()
1493 		return -ENODEV;  in pseudo_lock_dev_mmap()
1498 	 * with the pseudo-locked region. If this is not the case the task  in pseudo_lock_dev_mmap()
1500 	 * pseudo-locked region.  in pseudo_lock_dev_mmap()
1502 	if (!cpumask_subset(current->cpus_ptr, &plr->d->cpu_mask)) {  in pseudo_lock_dev_mmap()
1504 		return -EINVAL;  in pseudo_lock_dev_mmap()
1507 	physical = __pa(plr->kmem) >> PAGE_SHIFT;  in pseudo_lock_dev_mmap()
1508 	psize = plr->size - off;  in pseudo_lock_dev_mmap()
1510 	if (off > plr->size) {  in pseudo_lock_dev_mmap()
1512 		return -ENOSPC;  in pseudo_lock_dev_mmap()
1517 	 * do not allow copy-on-write mapping.  in pseudo_lock_dev_mmap()
1519 	if (!(vma->vm_flags & VM_SHARED)) {  in pseudo_lock_dev_mmap()
1521 		return -EINVAL;  in pseudo_lock_dev_mmap()
1526 		return -ENOSPC;  in pseudo_lock_dev_mmap()
1529 	memset(plr->kmem + off, 0, vsize);  in pseudo_lock_dev_mmap()
1531 	if (remap_pfn_range(vma, vma->vm_start, physical + vma->vm_pgoff,  in pseudo_lock_dev_mmap()
1532 			    vsize, vma->vm_page_prot)) {  in pseudo_lock_dev_mmap()
1534 		return -EAGAIN;  in pseudo_lock_dev_mmap()
1536 	vma->vm_ops = &pseudo_mmap_ops;  in pseudo_lock_dev_mmap()
1558 	return kasprintf(GFP_KERNEL, "pseudo_lock/%s", rdtgrp->kn->name);  in pseudo_lock_devnode()
1578 	pseudo_lock_class->devnode = pseudo_lock_devnode;  in rdt_pseudo_lock_init()