~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

TOMOYO Linux Cross Reference
Linux/kernel/irq/proc.c

Version: ~ [ linux-5.13-rc1 ] ~ [ linux-5.12.2 ] ~ [ linux-5.11.19 ] ~ [ linux-5.10.35 ] ~ [ linux-5.9.16 ] ~ [ linux-5.8.18 ] ~ [ linux-5.7.19 ] ~ [ linux-5.6.19 ] ~ [ linux-5.5.19 ] ~ [ linux-5.4.117 ] ~ [ linux-5.3.18 ] ~ [ linux-5.2.21 ] ~ [ linux-5.1.21 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.190 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.232 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.268 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.268 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.52 ] ~ [ linux-4.0.9 ] ~ [ linux-3.18.140 ] ~ [ linux-3.16.85 ] ~ [ linux-3.14.79 ] ~ [ linux-3.12.74 ] ~ [ linux-3.10.108 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.5 ] ~ [ policy-sample ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

  1 // SPDX-License-Identifier: GPL-2.0
  2 /*
  3  * linux/kernel/irq/proc.c
  4  *
  5  * Copyright (C) 1992, 1998-2004 Linus Torvalds, Ingo Molnar
  6  *
  7  * This file contains the /proc/irq/ handling code.
  8  */
  9 
 10 #include <linux/irq.h>
 11 #include <linux/gfp.h>
 12 #include <linux/proc_fs.h>
 13 #include <linux/seq_file.h>
 14 #include <linux/interrupt.h>
 15 #include <linux/kernel_stat.h>
 16 #include <linux/mutex.h>
 17 
 18 #include "internals.h"
 19 
 20 /*
 21  * Access rules:
 22  *
 23  * procfs protects read/write of /proc/irq/N/ files against a
 24  * concurrent free of the interrupt descriptor. remove_proc_entry()
 25  * immediately prevents new read/writes to happen and waits for
 26  * already running read/write functions to complete.
 27  *
 28  * We remove the proc entries first and then delete the interrupt
 29  * descriptor from the radix tree and free it. So it is guaranteed
 30  * that irq_to_desc(N) is valid as long as the read/writes are
 31  * permitted by procfs.
 32  *
 33  * The read from /proc/interrupts is a different problem because there
 34  * is no protection. So the lookup and the access to irqdesc
 35  * information must be protected by sparse_irq_lock.
 36  */
 37 static struct proc_dir_entry *root_irq_dir;
 38 
 39 #ifdef CONFIG_SMP
 40 
 41 enum {
 42         AFFINITY,
 43         AFFINITY_LIST,
 44         EFFECTIVE,
 45         EFFECTIVE_LIST,
 46 };
 47 
 48 static int show_irq_affinity(int type, struct seq_file *m)
 49 {
 50         struct irq_desc *desc = irq_to_desc((long)m->private);
 51         const struct cpumask *mask;
 52 
 53         switch (type) {
 54         case AFFINITY:
 55         case AFFINITY_LIST:
 56                 mask = desc->irq_common_data.affinity;
 57 #ifdef CONFIG_GENERIC_PENDING_IRQ
 58                 if (irqd_is_setaffinity_pending(&desc->irq_data))
 59                         mask = desc->pending_mask;
 60 #endif
 61                 break;
 62         case EFFECTIVE:
 63         case EFFECTIVE_LIST:
 64 #ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
 65                 mask = irq_data_get_effective_affinity_mask(&desc->irq_data);
 66                 break;
 67 #endif
 68         default:
 69                 return -EINVAL;
 70         }
 71 
 72         switch (type) {
 73         case AFFINITY_LIST:
 74         case EFFECTIVE_LIST:
 75                 seq_printf(m, "%*pbl\n", cpumask_pr_args(mask));
 76                 break;
 77         case AFFINITY:
 78         case EFFECTIVE:
 79                 seq_printf(m, "%*pb\n", cpumask_pr_args(mask));
 80                 break;
 81         }
 82         return 0;
 83 }
 84 
 85 static int irq_affinity_hint_proc_show(struct seq_file *m, void *v)
 86 {
 87         struct irq_desc *desc = irq_to_desc((long)m->private);
 88         unsigned long flags;
 89         cpumask_var_t mask;
 90 
 91         if (!zalloc_cpumask_var(&mask, GFP_KERNEL))
 92                 return -ENOMEM;
 93 
 94         raw_spin_lock_irqsave(&desc->lock, flags);
 95         if (desc->affinity_hint)
 96                 cpumask_copy(mask, desc->affinity_hint);
 97         raw_spin_unlock_irqrestore(&desc->lock, flags);
 98 
 99         seq_printf(m, "%*pb\n", cpumask_pr_args(mask));
100         free_cpumask_var(mask);
101 
102         return 0;
103 }
104 
105 #ifndef is_affinity_mask_valid
106 #define is_affinity_mask_valid(val) 1
107 #endif
108 
109 int no_irq_affinity;
110 static int irq_affinity_proc_show(struct seq_file *m, void *v)
111 {
112         return show_irq_affinity(AFFINITY, m);
113 }
114 
115 static int irq_affinity_list_proc_show(struct seq_file *m, void *v)
116 {
117         return show_irq_affinity(AFFINITY_LIST, m);
118 }
119 
120 
121 static ssize_t write_irq_affinity(int type, struct file *file,
122                 const char __user *buffer, size_t count, loff_t *pos)
123 {
124         unsigned int irq = (int)(long)PDE_DATA(file_inode(file));
125         cpumask_var_t new_value;
126         int err;
127 
128         if (!irq_can_set_affinity_usr(irq) || no_irq_affinity)
129                 return -EIO;
130 
131         if (!alloc_cpumask_var(&new_value, GFP_KERNEL))
132                 return -ENOMEM;
133 
134         if (type)
135                 err = cpumask_parselist_user(buffer, count, new_value);
136         else
137                 err = cpumask_parse_user(buffer, count, new_value);
138         if (err)
139                 goto free_cpumask;
140 
141         if (!is_affinity_mask_valid(new_value)) {
142                 err = -EINVAL;
143                 goto free_cpumask;
144         }
145 
146         /*
147          * Do not allow disabling IRQs completely - it's a too easy
148          * way to make the system unusable accidentally :-) At least
149          * one online CPU still has to be targeted.
150          */
151         if (!cpumask_intersects(new_value, cpu_online_mask)) {
152                 /*
153                  * Special case for empty set - allow the architecture code
154                  * to set default SMP affinity.
155                  */
156                 err = irq_select_affinity_usr(irq) ? -EINVAL : count;
157         } else {
158                 err = irq_set_affinity(irq, new_value);
159                 if (!err)
160                         err = count;
161         }
162 
163 free_cpumask:
164         free_cpumask_var(new_value);
165         return err;
166 }
167 
168 static ssize_t irq_affinity_proc_write(struct file *file,
169                 const char __user *buffer, size_t count, loff_t *pos)
170 {
171         return write_irq_affinity(0, file, buffer, count, pos);
172 }
173 
174 static ssize_t irq_affinity_list_proc_write(struct file *file,
175                 const char __user *buffer, size_t count, loff_t *pos)
176 {
177         return write_irq_affinity(1, file, buffer, count, pos);
178 }
179 
180 static int irq_affinity_proc_open(struct inode *inode, struct file *file)
181 {
182         return single_open(file, irq_affinity_proc_show, PDE_DATA(inode));
183 }
184 
185 static int irq_affinity_list_proc_open(struct inode *inode, struct file *file)
186 {
187         return single_open(file, irq_affinity_list_proc_show, PDE_DATA(inode));
188 }
189 
190 static int irq_affinity_hint_proc_open(struct inode *inode, struct file *file)
191 {
192         return single_open(file, irq_affinity_hint_proc_show, PDE_DATA(inode));
193 }
194 
195 static const struct file_operations irq_affinity_proc_fops = {
196         .open           = irq_affinity_proc_open,
197         .read           = seq_read,
198         .llseek         = seq_lseek,
199         .release        = single_release,
200         .write          = irq_affinity_proc_write,
201 };
202 
203 static const struct file_operations irq_affinity_hint_proc_fops = {
204         .open           = irq_affinity_hint_proc_open,
205         .read           = seq_read,
206         .llseek         = seq_lseek,
207         .release        = single_release,
208 };
209 
210 static const struct file_operations irq_affinity_list_proc_fops = {
211         .open           = irq_affinity_list_proc_open,
212         .read           = seq_read,
213         .llseek         = seq_lseek,
214         .release        = single_release,
215         .write          = irq_affinity_list_proc_write,
216 };
217 
218 #ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
219 static int irq_effective_aff_proc_show(struct seq_file *m, void *v)
220 {
221         return show_irq_affinity(EFFECTIVE, m);
222 }
223 
224 static int irq_effective_aff_list_proc_show(struct seq_file *m, void *v)
225 {
226         return show_irq_affinity(EFFECTIVE_LIST, m);
227 }
228 
229 static int irq_effective_aff_proc_open(struct inode *inode, struct file *file)
230 {
231         return single_open(file, irq_effective_aff_proc_show, PDE_DATA(inode));
232 }
233 
234 static int irq_effective_aff_list_proc_open(struct inode *inode,
235                                             struct file *file)
236 {
237         return single_open(file, irq_effective_aff_list_proc_show,
238                            PDE_DATA(inode));
239 }
240 
241 static const struct file_operations irq_effective_aff_proc_fops = {
242         .open           = irq_effective_aff_proc_open,
243         .read           = seq_read,
244         .llseek         = seq_lseek,
245         .release        = single_release,
246 };
247 
248 static const struct file_operations irq_effective_aff_list_proc_fops = {
249         .open           = irq_effective_aff_list_proc_open,
250         .read           = seq_read,
251         .llseek         = seq_lseek,
252         .release        = single_release,
253 };
254 #endif
255 
256 static int default_affinity_show(struct seq_file *m, void *v)
257 {
258         seq_printf(m, "%*pb\n", cpumask_pr_args(irq_default_affinity));
259         return 0;
260 }
261 
262 static ssize_t default_affinity_write(struct file *file,
263                 const char __user *buffer, size_t count, loff_t *ppos)
264 {
265         cpumask_var_t new_value;
266         int err;
267 
268         if (!alloc_cpumask_var(&new_value, GFP_KERNEL))
269                 return -ENOMEM;
270 
271         err = cpumask_parse_user(buffer, count, new_value);
272         if (err)
273                 goto out;
274 
275         if (!is_affinity_mask_valid(new_value)) {
276                 err = -EINVAL;
277                 goto out;
278         }
279 
280         /*
281          * Do not allow disabling IRQs completely - it's a too easy
282          * way to make the system unusable accidentally :-) At least
283          * one online CPU still has to be targeted.
284          */
285         if (!cpumask_intersects(new_value, cpu_online_mask)) {
286                 err = -EINVAL;
287                 goto out;
288         }
289 
290         cpumask_copy(irq_default_affinity, new_value);
291         err = count;
292 
293 out:
294         free_cpumask_var(new_value);
295         return err;
296 }
297 
298 static int default_affinity_open(struct inode *inode, struct file *file)
299 {
300         return single_open(file, default_affinity_show, PDE_DATA(inode));
301 }
302 
303 static const struct file_operations default_affinity_proc_fops = {
304         .open           = default_affinity_open,
305         .read           = seq_read,
306         .llseek         = seq_lseek,
307         .release        = single_release,
308         .write          = default_affinity_write,
309 };
310 
311 static int irq_node_proc_show(struct seq_file *m, void *v)
312 {
313         struct irq_desc *desc = irq_to_desc((long) m->private);
314 
315         seq_printf(m, "%d\n", irq_desc_get_node(desc));
316         return 0;
317 }
318 
319 static int irq_node_proc_open(struct inode *inode, struct file *file)
320 {
321         return single_open(file, irq_node_proc_show, PDE_DATA(inode));
322 }
323 
324 static const struct file_operations irq_node_proc_fops = {
325         .open           = irq_node_proc_open,
326         .read           = seq_read,
327         .llseek         = seq_lseek,
328         .release        = single_release,
329 };
330 #endif
331 
332 static int irq_spurious_proc_show(struct seq_file *m, void *v)
333 {
334         struct irq_desc *desc = irq_to_desc((long) m->private);
335 
336         seq_printf(m, "count %u\n" "unhandled %u\n" "last_unhandled %u ms\n",
337                    desc->irq_count, desc->irqs_unhandled,
338                    jiffies_to_msecs(desc->last_unhandled));
339         return 0;
340 }
341 
342 static int irq_spurious_proc_open(struct inode *inode, struct file *file)
343 {
344         return single_open(file, irq_spurious_proc_show, PDE_DATA(inode));
345 }
346 
347 static const struct file_operations irq_spurious_proc_fops = {
348         .open           = irq_spurious_proc_open,
349         .read           = seq_read,
350         .llseek         = seq_lseek,
351         .release        = single_release,
352 };
353 
354 #define MAX_NAMELEN 128
355 
356 static int name_unique(unsigned int irq, struct irqaction *new_action)
357 {
358         struct irq_desc *desc = irq_to_desc(irq);
359         struct irqaction *action;
360         unsigned long flags;
361         int ret = 1;
362 
363         raw_spin_lock_irqsave(&desc->lock, flags);
364         for_each_action_of_desc(desc, action) {
365                 if ((action != new_action) && action->name &&
366                                 !strcmp(new_action->name, action->name)) {
367                         ret = 0;
368                         break;
369                 }
370         }
371         raw_spin_unlock_irqrestore(&desc->lock, flags);
372         return ret;
373 }
374 
375 void register_handler_proc(unsigned int irq, struct irqaction *action)
376 {
377         char name [MAX_NAMELEN];
378         struct irq_desc *desc = irq_to_desc(irq);
379 
380         if (!desc->dir || action->dir || !action->name ||
381                                         !name_unique(irq, action))
382                 return;
383 
384         snprintf(name, MAX_NAMELEN, "%s", action->name);
385 
386         /* create /proc/irq/1234/handler/ */
387         action->dir = proc_mkdir(name, desc->dir);
388 }
389 
390 #undef MAX_NAMELEN
391 
392 #define MAX_NAMELEN 10
393 
394 void register_irq_proc(unsigned int irq, struct irq_desc *desc)
395 {
396         static DEFINE_MUTEX(register_lock);
397         void __maybe_unused *irqp = (void *)(unsigned long) irq;
398         char name [MAX_NAMELEN];
399 
400         if (!root_irq_dir || (desc->irq_data.chip == &no_irq_chip))
401                 return;
402 
403         /*
404          * irq directories are registered only when a handler is
405          * added, not when the descriptor is created, so multiple
406          * tasks might try to register at the same time.
407          */
408         mutex_lock(&register_lock);
409 
410         if (desc->dir)
411                 goto out_unlock;
412 
413         sprintf(name, "%d", irq);
414 
415         /* create /proc/irq/1234 */
416         desc->dir = proc_mkdir(name, root_irq_dir);
417         if (!desc->dir)
418                 goto out_unlock;
419 
420 #ifdef CONFIG_SMP
421         /* create /proc/irq/<irq>/smp_affinity */
422         proc_create_data("smp_affinity", 0644, desc->dir,
423                          &irq_affinity_proc_fops, irqp);
424 
425         /* create /proc/irq/<irq>/affinity_hint */
426         proc_create_data("affinity_hint", 0444, desc->dir,
427                          &irq_affinity_hint_proc_fops, irqp);
428 
429         /* create /proc/irq/<irq>/smp_affinity_list */
430         proc_create_data("smp_affinity_list", 0644, desc->dir,
431                          &irq_affinity_list_proc_fops, irqp);
432 
433         proc_create_data("node", 0444, desc->dir,
434                          &irq_node_proc_fops, irqp);
435 # ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
436         proc_create_data("effective_affinity", 0444, desc->dir,
437                          &irq_effective_aff_proc_fops, irqp);
438         proc_create_data("effective_affinity_list", 0444, desc->dir,
439                          &irq_effective_aff_list_proc_fops, irqp);
440 # endif
441 #endif
442         proc_create_data("spurious", 0444, desc->dir,
443                          &irq_spurious_proc_fops, (void *)(long)irq);
444 
445 out_unlock:
446         mutex_unlock(&register_lock);
447 }
448 
449 void unregister_irq_proc(unsigned int irq, struct irq_desc *desc)
450 {
451         char name [MAX_NAMELEN];
452 
453         if (!root_irq_dir || !desc->dir)
454                 return;
455 #ifdef CONFIG_SMP
456         remove_proc_entry("smp_affinity", desc->dir);
457         remove_proc_entry("affinity_hint", desc->dir);
458         remove_proc_entry("smp_affinity_list", desc->dir);
459         remove_proc_entry("node", desc->dir);
460 # ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
461         remove_proc_entry("effective_affinity", desc->dir);
462         remove_proc_entry("effective_affinity_list", desc->dir);
463 # endif
464 #endif
465         remove_proc_entry("spurious", desc->dir);
466 
467         sprintf(name, "%u", irq);
468         remove_proc_entry(name, root_irq_dir);
469 }
470 
471 #undef MAX_NAMELEN
472 
473 void unregister_handler_proc(unsigned int irq, struct irqaction *action)
474 {
475         proc_remove(action->dir);
476 }
477 
478 static void register_default_affinity_proc(void)
479 {
480 #ifdef CONFIG_SMP
481         proc_create("irq/default_smp_affinity", 0644, NULL,
482                     &default_affinity_proc_fops);
483 #endif
484 }
485 
486 void init_irq_proc(void)
487 {
488         unsigned int irq;
489         struct irq_desc *desc;
490 
491         /* create /proc/irq */
492         root_irq_dir = proc_mkdir("irq", NULL);
493         if (!root_irq_dir)
494                 return;
495 
496         register_default_affinity_proc();
497 
498         /*
499          * Create entries for all existing IRQs.
500          */
501         for_each_irq_desc(irq, desc)
502                 register_irq_proc(irq, desc);
503 }
504 
505 #ifdef CONFIG_GENERIC_IRQ_SHOW
506 
507 int __weak arch_show_interrupts(struct seq_file *p, int prec)
508 {
509         return 0;
510 }
511 
512 #ifndef ACTUAL_NR_IRQS
513 # define ACTUAL_NR_IRQS nr_irqs
514 #endif
515 
516 int show_interrupts(struct seq_file *p, void *v)
517 {
518         static int prec;
519 
520         unsigned long flags, any_count = 0;
521         int i = *(loff_t *) v, j;
522         struct irqaction *action;
523         struct irq_desc *desc;
524 
525         if (i > ACTUAL_NR_IRQS)
526                 return 0;
527 
528         if (i == ACTUAL_NR_IRQS)
529                 return arch_show_interrupts(p, prec);
530 
531         /* print header and calculate the width of the first column */
532         if (i == 0) {
533                 for (prec = 3, j = 1000; prec < 10 && j <= nr_irqs; ++prec)
534                         j *= 10;
535 
536                 seq_printf(p, "%*s", prec + 8, "");
537                 for_each_online_cpu(j)
538                         seq_printf(p, "CPU%-8d", j);
539                 seq_putc(p, '\n');
540         }
541 
542         irq_lock_sparse();
543         desc = irq_to_desc(i);
544         if (!desc)
545                 goto outsparse;
546 
547         raw_spin_lock_irqsave(&desc->lock, flags);
548         for_each_online_cpu(j)
549                 any_count |= kstat_irqs_cpu(i, j);
550         action = desc->action;
551         if ((!action || irq_desc_is_chained(desc)) && !any_count)
552                 goto out;
553 
554         seq_printf(p, "%*d: ", prec, i);
555         for_each_online_cpu(j)
556                 seq_printf(p, "%10u ", kstat_irqs_cpu(i, j));
557 
558         if (desc->irq_data.chip) {
559                 if (desc->irq_data.chip->irq_print_chip)
560                         desc->irq_data.chip->irq_print_chip(&desc->irq_data, p);
561                 else if (desc->irq_data.chip->name)
562                         seq_printf(p, " %8s", desc->irq_data.chip->name);
563                 else
564                         seq_printf(p, " %8s", "-");
565         } else {
566                 seq_printf(p, " %8s", "None");
567         }
568         if (desc->irq_data.domain)
569                 seq_printf(p, " %*d", prec, (int) desc->irq_data.hwirq);
570         else
571                 seq_printf(p, " %*s", prec, "");
572 #ifdef CONFIG_GENERIC_IRQ_SHOW_LEVEL
573         seq_printf(p, " %-8s", irqd_is_level_type(&desc->irq_data) ? "Level" : "Edge");
574 #endif
575         if (desc->name)
576                 seq_printf(p, "-%-8s", desc->name);
577 
578         if (action) {
579                 seq_printf(p, "  %s", action->name);
580                 while ((action = action->next) != NULL)
581                         seq_printf(p, ", %s", action->name);
582         }
583 
584         seq_putc(p, '\n');
585 out:
586         raw_spin_unlock_irqrestore(&desc->lock, flags);
587 outsparse:
588         irq_unlock_sparse();
589         return 0;
590 }
591 #endif
592 

~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

kernel.org | git.kernel.org | LWN.net | Project Home | Wiki (Japanese) | Wiki (English) | SVN repository | Mail admin

Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.

osdn.jp