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v4.17
  1// SPDX-License-Identifier: GPL-2.0
  2// Copyright (C) 2017 Thomas Gleixner <tglx@linutronix.de>
  3
  4#include <linux/spinlock.h>
  5#include <linux/seq_file.h>
  6#include <linux/bitmap.h>
  7#include <linux/percpu.h>
  8#include <linux/cpu.h>
  9#include <linux/irq.h>
 10
 11#define IRQ_MATRIX_SIZE	(BITS_TO_LONGS(IRQ_MATRIX_BITS) * sizeof(unsigned long))
 12
 13struct cpumap {
 14	unsigned int		available;
 15	unsigned int		allocated;
 16	unsigned int		managed;
 
 17	bool			initialized;
 18	bool			online;
 19	unsigned long		alloc_map[IRQ_MATRIX_SIZE];
 20	unsigned long		managed_map[IRQ_MATRIX_SIZE];
 21};
 22
 23struct irq_matrix {
 24	unsigned int		matrix_bits;
 25	unsigned int		alloc_start;
 26	unsigned int		alloc_end;
 27	unsigned int		alloc_size;
 28	unsigned int		global_available;
 29	unsigned int		global_reserved;
 30	unsigned int		systembits_inalloc;
 31	unsigned int		total_allocated;
 32	unsigned int		online_maps;
 33	struct cpumap __percpu	*maps;
 34	unsigned long		scratch_map[IRQ_MATRIX_SIZE];
 35	unsigned long		system_map[IRQ_MATRIX_SIZE];
 36};
 37
 38#define CREATE_TRACE_POINTS
 39#include <trace/events/irq_matrix.h>
 40
 41/**
 42 * irq_alloc_matrix - Allocate a irq_matrix structure and initialize it
 43 * @matrix_bits:	Number of matrix bits must be <= IRQ_MATRIX_BITS
 44 * @alloc_start:	From which bit the allocation search starts
 45 * @alloc_end:		At which bit the allocation search ends, i.e first
 46 *			invalid bit
 47 */
 48__init struct irq_matrix *irq_alloc_matrix(unsigned int matrix_bits,
 49					   unsigned int alloc_start,
 50					   unsigned int alloc_end)
 51{
 
 52	struct irq_matrix *m;
 53
 54	if (matrix_bits > IRQ_MATRIX_BITS)
 55		return NULL;
 56
 57	m = kzalloc(sizeof(*m), GFP_KERNEL);
 58	if (!m)
 59		return NULL;
 60
 
 
 61	m->matrix_bits = matrix_bits;
 62	m->alloc_start = alloc_start;
 63	m->alloc_end = alloc_end;
 64	m->alloc_size = alloc_end - alloc_start;
 65	m->maps = alloc_percpu(*m->maps);
 
 66	if (!m->maps) {
 67		kfree(m);
 68		return NULL;
 69	}
 
 
 
 
 
 
 
 70	return m;
 71}
 72
 73/**
 74 * irq_matrix_online - Bring the local CPU matrix online
 75 * @m:		Matrix pointer
 76 */
 77void irq_matrix_online(struct irq_matrix *m)
 78{
 79	struct cpumap *cm = this_cpu_ptr(m->maps);
 80
 81	BUG_ON(cm->online);
 82
 83	if (!cm->initialized) {
 84		cm->available = m->alloc_size;
 85		cm->available -= cm->managed + m->systembits_inalloc;
 86		cm->initialized = true;
 87	}
 88	m->global_available += cm->available;
 89	cm->online = true;
 90	m->online_maps++;
 91	trace_irq_matrix_online(m);
 92}
 93
 94/**
 95 * irq_matrix_offline - Bring the local CPU matrix offline
 96 * @m:		Matrix pointer
 97 */
 98void irq_matrix_offline(struct irq_matrix *m)
 99{
100	struct cpumap *cm = this_cpu_ptr(m->maps);
101
102	/* Update the global available size */
103	m->global_available -= cm->available;
104	cm->online = false;
105	m->online_maps--;
106	trace_irq_matrix_offline(m);
107}
108
109static unsigned int matrix_alloc_area(struct irq_matrix *m, struct cpumap *cm,
110				      unsigned int num, bool managed)
111{
112	unsigned int area, start = m->alloc_start;
113	unsigned int end = m->alloc_end;
114
115	bitmap_or(m->scratch_map, cm->managed_map, m->system_map, end);
116	bitmap_or(m->scratch_map, m->scratch_map, cm->alloc_map, end);
117	area = bitmap_find_next_zero_area(m->scratch_map, end, start, num, 0);
118	if (area >= end)
119		return area;
120	if (managed)
121		bitmap_set(cm->managed_map, area, num);
122	else
123		bitmap_set(cm->alloc_map, area, num);
124	return area;
125}
126
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
127/**
128 * irq_matrix_assign_system - Assign system wide entry in the matrix
129 * @m:		Matrix pointer
130 * @bit:	Which bit to reserve
131 * @replace:	Replace an already allocated vector with a system
132 *		vector at the same bit position.
133 *
134 * The BUG_ON()s below are on purpose. If this goes wrong in the
135 * early boot process, then the chance to survive is about zero.
136 * If this happens when the system is life, it's not much better.
137 */
138void irq_matrix_assign_system(struct irq_matrix *m, unsigned int bit,
139			      bool replace)
140{
141	struct cpumap *cm = this_cpu_ptr(m->maps);
142
143	BUG_ON(bit > m->matrix_bits);
144	BUG_ON(m->online_maps > 1 || (m->online_maps && !replace));
145
146	set_bit(bit, m->system_map);
147	if (replace) {
148		BUG_ON(!test_and_clear_bit(bit, cm->alloc_map));
149		cm->allocated--;
150		m->total_allocated--;
151	}
152	if (bit >= m->alloc_start && bit < m->alloc_end)
153		m->systembits_inalloc++;
154
155	trace_irq_matrix_assign_system(bit, m);
156}
157
158/**
159 * irq_matrix_reserve_managed - Reserve a managed interrupt in a CPU map
160 * @m:		Matrix pointer
161 * @msk:	On which CPUs the bits should be reserved.
162 *
163 * Can be called for offline CPUs. Note, this will only reserve one bit
164 * on all CPUs in @msk, but it's not guaranteed that the bits are at the
165 * same offset on all CPUs
166 */
167int irq_matrix_reserve_managed(struct irq_matrix *m, const struct cpumask *msk)
168{
169	unsigned int cpu, failed_cpu;
170
171	for_each_cpu(cpu, msk) {
172		struct cpumap *cm = per_cpu_ptr(m->maps, cpu);
173		unsigned int bit;
174
175		bit = matrix_alloc_area(m, cm, 1, true);
176		if (bit >= m->alloc_end)
177			goto cleanup;
178		cm->managed++;
179		if (cm->online) {
180			cm->available--;
181			m->global_available--;
182		}
183		trace_irq_matrix_reserve_managed(bit, cpu, m, cm);
184	}
185	return 0;
186cleanup:
187	failed_cpu = cpu;
188	for_each_cpu(cpu, msk) {
189		if (cpu == failed_cpu)
190			break;
191		irq_matrix_remove_managed(m, cpumask_of(cpu));
192	}
193	return -ENOSPC;
194}
195
196/**
197 * irq_matrix_remove_managed - Remove managed interrupts in a CPU map
198 * @m:		Matrix pointer
199 * @msk:	On which CPUs the bits should be removed
200 *
201 * Can be called for offline CPUs
202 *
203 * This removes not allocated managed interrupts from the map. It does
204 * not matter which one because the managed interrupts free their
205 * allocation when they shut down. If not, the accounting is screwed,
206 * but all what can be done at this point is warn about it.
207 */
208void irq_matrix_remove_managed(struct irq_matrix *m, const struct cpumask *msk)
209{
210	unsigned int cpu;
211
212	for_each_cpu(cpu, msk) {
213		struct cpumap *cm = per_cpu_ptr(m->maps, cpu);
214		unsigned int bit, end = m->alloc_end;
215
216		if (WARN_ON_ONCE(!cm->managed))
217			continue;
218
219		/* Get managed bit which are not allocated */
220		bitmap_andnot(m->scratch_map, cm->managed_map, cm->alloc_map, end);
221
222		bit = find_first_bit(m->scratch_map, end);
223		if (WARN_ON_ONCE(bit >= end))
224			continue;
225
226		clear_bit(bit, cm->managed_map);
227
228		cm->managed--;
229		if (cm->online) {
230			cm->available++;
231			m->global_available++;
232		}
233		trace_irq_matrix_remove_managed(bit, cpu, m, cm);
234	}
235}
236
237/**
238 * irq_matrix_alloc_managed - Allocate a managed interrupt in a CPU map
239 * @m:		Matrix pointer
240 * @cpu:	On which CPU the interrupt should be allocated
 
241 */
242int irq_matrix_alloc_managed(struct irq_matrix *m, unsigned int cpu)
 
243{
244	struct cpumap *cm = per_cpu_ptr(m->maps, cpu);
245	unsigned int bit, end = m->alloc_end;
 
 
 
246
 
 
 
 
 
 
247	/* Get managed bit which are not allocated */
248	bitmap_andnot(m->scratch_map, cm->managed_map, cm->alloc_map, end);
249	bit = find_first_bit(m->scratch_map, end);
250	if (bit >= end)
251		return -ENOSPC;
252	set_bit(bit, cm->alloc_map);
253	cm->allocated++;
 
254	m->total_allocated++;
 
255	trace_irq_matrix_alloc_managed(bit, cpu, m, cm);
256	return bit;
257}
258
259/**
260 * irq_matrix_assign - Assign a preallocated interrupt in the local CPU map
261 * @m:		Matrix pointer
262 * @bit:	Which bit to mark
263 *
264 * This should only be used to mark preallocated vectors
265 */
266void irq_matrix_assign(struct irq_matrix *m, unsigned int bit)
267{
268	struct cpumap *cm = this_cpu_ptr(m->maps);
269
270	if (WARN_ON_ONCE(bit < m->alloc_start || bit >= m->alloc_end))
271		return;
272	if (WARN_ON_ONCE(test_and_set_bit(bit, cm->alloc_map)))
273		return;
274	cm->allocated++;
275	m->total_allocated++;
276	cm->available--;
277	m->global_available--;
278	trace_irq_matrix_assign(bit, smp_processor_id(), m, cm);
279}
280
281/**
282 * irq_matrix_reserve - Reserve interrupts
283 * @m:		Matrix pointer
284 *
285 * This is merily a book keeping call. It increments the number of globally
286 * reserved interrupt bits w/o actually allocating them. This allows to
287 * setup interrupt descriptors w/o assigning low level resources to it.
288 * The actual allocation happens when the interrupt gets activated.
289 */
290void irq_matrix_reserve(struct irq_matrix *m)
291{
292	if (m->global_reserved <= m->global_available &&
293	    m->global_reserved + 1 > m->global_available)
294		pr_warn("Interrupt reservation exceeds available resources\n");
295
296	m->global_reserved++;
297	trace_irq_matrix_reserve(m);
298}
299
300/**
301 * irq_matrix_remove_reserved - Remove interrupt reservation
302 * @m:		Matrix pointer
303 *
304 * This is merily a book keeping call. It decrements the number of globally
305 * reserved interrupt bits. This is used to undo irq_matrix_reserve() when the
306 * interrupt was never in use and a real vector allocated, which undid the
307 * reservation.
308 */
309void irq_matrix_remove_reserved(struct irq_matrix *m)
310{
311	m->global_reserved--;
312	trace_irq_matrix_remove_reserved(m);
313}
314
315/**
316 * irq_matrix_alloc - Allocate a regular interrupt in a CPU map
317 * @m:		Matrix pointer
318 * @msk:	Which CPUs to search in
319 * @reserved:	Allocate previously reserved interrupts
320 * @mapped_cpu: Pointer to store the CPU for which the irq was allocated
321 */
322int irq_matrix_alloc(struct irq_matrix *m, const struct cpumask *msk,
323		     bool reserved, unsigned int *mapped_cpu)
324{
325	unsigned int cpu, best_cpu, maxavl = 0;
326	struct cpumap *cm;
327	unsigned int bit;
328
329	best_cpu = UINT_MAX;
330	for_each_cpu(cpu, msk) {
331		cm = per_cpu_ptr(m->maps, cpu);
 
 
 
332
333		if (!cm->online || cm->available <= maxavl)
334			continue;
 
335
336		best_cpu = cpu;
337		maxavl = cm->available;
338	}
 
 
 
 
 
 
 
 
 
 
339
340	if (maxavl) {
341		cm = per_cpu_ptr(m->maps, best_cpu);
342		bit = matrix_alloc_area(m, cm, 1, false);
343		if (bit < m->alloc_end) {
344			cm->allocated++;
345			cm->available--;
346			m->total_allocated++;
347			m->global_available--;
348			if (reserved)
349				m->global_reserved--;
350			*mapped_cpu = best_cpu;
351			trace_irq_matrix_alloc(bit, best_cpu, m, cm);
352			return bit;
353		}
354	}
355	return -ENOSPC;
356}
357
358/**
359 * irq_matrix_free - Free allocated interrupt in the matrix
360 * @m:		Matrix pointer
361 * @cpu:	Which CPU map needs be updated
362 * @bit:	The bit to remove
363 * @managed:	If true, the interrupt is managed and not accounted
364 *		as available.
365 */
366void irq_matrix_free(struct irq_matrix *m, unsigned int cpu,
367		     unsigned int bit, bool managed)
368{
369	struct cpumap *cm = per_cpu_ptr(m->maps, cpu);
370
371	if (WARN_ON_ONCE(bit < m->alloc_start || bit >= m->alloc_end))
372		return;
373
374	clear_bit(bit, cm->alloc_map);
 
 
375	cm->allocated--;
 
 
376
377	if (cm->online)
378		m->total_allocated--;
379
380	if (!managed) {
381		cm->available++;
382		if (cm->online)
383			m->global_available++;
384	}
385	trace_irq_matrix_free(bit, cpu, m, cm);
386}
387
388/**
389 * irq_matrix_available - Get the number of globally available irqs
390 * @m:		Pointer to the matrix to query
391 * @cpudown:	If true, the local CPU is about to go down, adjust
392 *		the number of available irqs accordingly
393 */
394unsigned int irq_matrix_available(struct irq_matrix *m, bool cpudown)
395{
396	struct cpumap *cm = this_cpu_ptr(m->maps);
397
398	if (!cpudown)
399		return m->global_available;
400	return m->global_available - cm->available;
401}
402
403/**
404 * irq_matrix_reserved - Get the number of globally reserved irqs
405 * @m:		Pointer to the matrix to query
406 */
407unsigned int irq_matrix_reserved(struct irq_matrix *m)
408{
409	return m->global_reserved;
410}
411
412/**
413 * irq_matrix_allocated - Get the number of allocated irqs on the local cpu
414 * @m:		Pointer to the matrix to search
415 *
416 * This returns number of allocated irqs
417 */
418unsigned int irq_matrix_allocated(struct irq_matrix *m)
419{
420	struct cpumap *cm = this_cpu_ptr(m->maps);
421
422	return cm->allocated;
423}
424
425#ifdef CONFIG_GENERIC_IRQ_DEBUGFS
426/**
427 * irq_matrix_debug_show - Show detailed allocation information
428 * @sf:		Pointer to the seq_file to print to
429 * @m:		Pointer to the matrix allocator
430 * @ind:	Indentation for the print format
431 *
432 * Note, this is a lockless snapshot.
433 */
434void irq_matrix_debug_show(struct seq_file *sf, struct irq_matrix *m, int ind)
435{
436	unsigned int nsys = bitmap_weight(m->system_map, m->matrix_bits);
437	int cpu;
438
439	seq_printf(sf, "Online bitmaps:   %6u\n", m->online_maps);
440	seq_printf(sf, "Global available: %6u\n", m->global_available);
441	seq_printf(sf, "Global reserved:  %6u\n", m->global_reserved);
442	seq_printf(sf, "Total allocated:  %6u\n", m->total_allocated);
443	seq_printf(sf, "System: %u: %*pbl\n", nsys, m->matrix_bits,
444		   m->system_map);
445	seq_printf(sf, "%*s| CPU | avl | man | act | vectors\n", ind, " ");
446	cpus_read_lock();
447	for_each_online_cpu(cpu) {
448		struct cpumap *cm = per_cpu_ptr(m->maps, cpu);
449
450		seq_printf(sf, "%*s %4d  %4u  %4u  %4u  %*pbl\n", ind, " ",
451			   cpu, cm->available, cm->managed, cm->allocated,
 
452			   m->matrix_bits, cm->alloc_map);
453	}
454	cpus_read_unlock();
455}
456#endif
v6.9.4
  1// SPDX-License-Identifier: GPL-2.0
  2// Copyright (C) 2017 Thomas Gleixner <tglx@linutronix.de>
  3
  4#include <linux/spinlock.h>
  5#include <linux/seq_file.h>
  6#include <linux/bitmap.h>
  7#include <linux/percpu.h>
  8#include <linux/cpu.h>
  9#include <linux/irq.h>
 10
 
 
 11struct cpumap {
 12	unsigned int		available;
 13	unsigned int		allocated;
 14	unsigned int		managed;
 15	unsigned int		managed_allocated;
 16	bool			initialized;
 17	bool			online;
 18	unsigned long		*managed_map;
 19	unsigned long		alloc_map[];
 20};
 21
 22struct irq_matrix {
 23	unsigned int		matrix_bits;
 24	unsigned int		alloc_start;
 25	unsigned int		alloc_end;
 26	unsigned int		alloc_size;
 27	unsigned int		global_available;
 28	unsigned int		global_reserved;
 29	unsigned int		systembits_inalloc;
 30	unsigned int		total_allocated;
 31	unsigned int		online_maps;
 32	struct cpumap __percpu	*maps;
 33	unsigned long		*system_map;
 34	unsigned long		scratch_map[];
 35};
 36
 37#define CREATE_TRACE_POINTS
 38#include <trace/events/irq_matrix.h>
 39
 40/**
 41 * irq_alloc_matrix - Allocate a irq_matrix structure and initialize it
 42 * @matrix_bits:	Number of matrix bits must be <= IRQ_MATRIX_BITS
 43 * @alloc_start:	From which bit the allocation search starts
 44 * @alloc_end:		At which bit the allocation search ends, i.e first
 45 *			invalid bit
 46 */
 47__init struct irq_matrix *irq_alloc_matrix(unsigned int matrix_bits,
 48					   unsigned int alloc_start,
 49					   unsigned int alloc_end)
 50{
 51	unsigned int cpu, matrix_size = BITS_TO_LONGS(matrix_bits);
 52	struct irq_matrix *m;
 53
 54	m = kzalloc(struct_size(m, scratch_map, matrix_size * 2), GFP_KERNEL);
 
 
 
 55	if (!m)
 56		return NULL;
 57
 58	m->system_map = &m->scratch_map[matrix_size];
 59
 60	m->matrix_bits = matrix_bits;
 61	m->alloc_start = alloc_start;
 62	m->alloc_end = alloc_end;
 63	m->alloc_size = alloc_end - alloc_start;
 64	m->maps = __alloc_percpu(struct_size(m->maps, alloc_map, matrix_size * 2),
 65				 __alignof__(*m->maps));
 66	if (!m->maps) {
 67		kfree(m);
 68		return NULL;
 69	}
 70
 71	for_each_possible_cpu(cpu) {
 72		struct cpumap *cm = per_cpu_ptr(m->maps, cpu);
 73
 74		cm->managed_map = &cm->alloc_map[matrix_size];
 75	}
 76
 77	return m;
 78}
 79
 80/**
 81 * irq_matrix_online - Bring the local CPU matrix online
 82 * @m:		Matrix pointer
 83 */
 84void irq_matrix_online(struct irq_matrix *m)
 85{
 86	struct cpumap *cm = this_cpu_ptr(m->maps);
 87
 88	BUG_ON(cm->online);
 89
 90	if (!cm->initialized) {
 91		cm->available = m->alloc_size;
 92		cm->available -= cm->managed + m->systembits_inalloc;
 93		cm->initialized = true;
 94	}
 95	m->global_available += cm->available;
 96	cm->online = true;
 97	m->online_maps++;
 98	trace_irq_matrix_online(m);
 99}
100
101/**
102 * irq_matrix_offline - Bring the local CPU matrix offline
103 * @m:		Matrix pointer
104 */
105void irq_matrix_offline(struct irq_matrix *m)
106{
107	struct cpumap *cm = this_cpu_ptr(m->maps);
108
109	/* Update the global available size */
110	m->global_available -= cm->available;
111	cm->online = false;
112	m->online_maps--;
113	trace_irq_matrix_offline(m);
114}
115
116static unsigned int matrix_alloc_area(struct irq_matrix *m, struct cpumap *cm,
117				      unsigned int num, bool managed)
118{
119	unsigned int area, start = m->alloc_start;
120	unsigned int end = m->alloc_end;
121
122	bitmap_or(m->scratch_map, cm->managed_map, m->system_map, end);
123	bitmap_or(m->scratch_map, m->scratch_map, cm->alloc_map, end);
124	area = bitmap_find_next_zero_area(m->scratch_map, end, start, num, 0);
125	if (area >= end)
126		return area;
127	if (managed)
128		bitmap_set(cm->managed_map, area, num);
129	else
130		bitmap_set(cm->alloc_map, area, num);
131	return area;
132}
133
134/* Find the best CPU which has the lowest vector allocation count */
135static unsigned int matrix_find_best_cpu(struct irq_matrix *m,
136					const struct cpumask *msk)
137{
138	unsigned int cpu, best_cpu, maxavl = 0;
139	struct cpumap *cm;
140
141	best_cpu = UINT_MAX;
142
143	for_each_cpu(cpu, msk) {
144		cm = per_cpu_ptr(m->maps, cpu);
145
146		if (!cm->online || cm->available <= maxavl)
147			continue;
148
149		best_cpu = cpu;
150		maxavl = cm->available;
151	}
152	return best_cpu;
153}
154
155/* Find the best CPU which has the lowest number of managed IRQs allocated */
156static unsigned int matrix_find_best_cpu_managed(struct irq_matrix *m,
157						const struct cpumask *msk)
158{
159	unsigned int cpu, best_cpu, allocated = UINT_MAX;
160	struct cpumap *cm;
161
162	best_cpu = UINT_MAX;
163
164	for_each_cpu(cpu, msk) {
165		cm = per_cpu_ptr(m->maps, cpu);
166
167		if (!cm->online || cm->managed_allocated > allocated)
168			continue;
169
170		best_cpu = cpu;
171		allocated = cm->managed_allocated;
172	}
173	return best_cpu;
174}
175
176/**
177 * irq_matrix_assign_system - Assign system wide entry in the matrix
178 * @m:		Matrix pointer
179 * @bit:	Which bit to reserve
180 * @replace:	Replace an already allocated vector with a system
181 *		vector at the same bit position.
182 *
183 * The BUG_ON()s below are on purpose. If this goes wrong in the
184 * early boot process, then the chance to survive is about zero.
185 * If this happens when the system is life, it's not much better.
186 */
187void irq_matrix_assign_system(struct irq_matrix *m, unsigned int bit,
188			      bool replace)
189{
190	struct cpumap *cm = this_cpu_ptr(m->maps);
191
192	BUG_ON(bit > m->matrix_bits);
193	BUG_ON(m->online_maps > 1 || (m->online_maps && !replace));
194
195	set_bit(bit, m->system_map);
196	if (replace) {
197		BUG_ON(!test_and_clear_bit(bit, cm->alloc_map));
198		cm->allocated--;
199		m->total_allocated--;
200	}
201	if (bit >= m->alloc_start && bit < m->alloc_end)
202		m->systembits_inalloc++;
203
204	trace_irq_matrix_assign_system(bit, m);
205}
206
207/**
208 * irq_matrix_reserve_managed - Reserve a managed interrupt in a CPU map
209 * @m:		Matrix pointer
210 * @msk:	On which CPUs the bits should be reserved.
211 *
212 * Can be called for offline CPUs. Note, this will only reserve one bit
213 * on all CPUs in @msk, but it's not guaranteed that the bits are at the
214 * same offset on all CPUs
215 */
216int irq_matrix_reserve_managed(struct irq_matrix *m, const struct cpumask *msk)
217{
218	unsigned int cpu, failed_cpu;
219
220	for_each_cpu(cpu, msk) {
221		struct cpumap *cm = per_cpu_ptr(m->maps, cpu);
222		unsigned int bit;
223
224		bit = matrix_alloc_area(m, cm, 1, true);
225		if (bit >= m->alloc_end)
226			goto cleanup;
227		cm->managed++;
228		if (cm->online) {
229			cm->available--;
230			m->global_available--;
231		}
232		trace_irq_matrix_reserve_managed(bit, cpu, m, cm);
233	}
234	return 0;
235cleanup:
236	failed_cpu = cpu;
237	for_each_cpu(cpu, msk) {
238		if (cpu == failed_cpu)
239			break;
240		irq_matrix_remove_managed(m, cpumask_of(cpu));
241	}
242	return -ENOSPC;
243}
244
245/**
246 * irq_matrix_remove_managed - Remove managed interrupts in a CPU map
247 * @m:		Matrix pointer
248 * @msk:	On which CPUs the bits should be removed
249 *
250 * Can be called for offline CPUs
251 *
252 * This removes not allocated managed interrupts from the map. It does
253 * not matter which one because the managed interrupts free their
254 * allocation when they shut down. If not, the accounting is screwed,
255 * but all what can be done at this point is warn about it.
256 */
257void irq_matrix_remove_managed(struct irq_matrix *m, const struct cpumask *msk)
258{
259	unsigned int cpu;
260
261	for_each_cpu(cpu, msk) {
262		struct cpumap *cm = per_cpu_ptr(m->maps, cpu);
263		unsigned int bit, end = m->alloc_end;
264
265		if (WARN_ON_ONCE(!cm->managed))
266			continue;
267
268		/* Get managed bit which are not allocated */
269		bitmap_andnot(m->scratch_map, cm->managed_map, cm->alloc_map, end);
270
271		bit = find_first_bit(m->scratch_map, end);
272		if (WARN_ON_ONCE(bit >= end))
273			continue;
274
275		clear_bit(bit, cm->managed_map);
276
277		cm->managed--;
278		if (cm->online) {
279			cm->available++;
280			m->global_available++;
281		}
282		trace_irq_matrix_remove_managed(bit, cpu, m, cm);
283	}
284}
285
286/**
287 * irq_matrix_alloc_managed - Allocate a managed interrupt in a CPU map
288 * @m:		Matrix pointer
289 * @msk:	Which CPUs to search in
290 * @mapped_cpu:	Pointer to store the CPU for which the irq was allocated
291 */
292int irq_matrix_alloc_managed(struct irq_matrix *m, const struct cpumask *msk,
293			     unsigned int *mapped_cpu)
294{
295	unsigned int bit, cpu, end;
296	struct cpumap *cm;
297
298	if (cpumask_empty(msk))
299		return -EINVAL;
300
301	cpu = matrix_find_best_cpu_managed(m, msk);
302	if (cpu == UINT_MAX)
303		return -ENOSPC;
304
305	cm = per_cpu_ptr(m->maps, cpu);
306	end = m->alloc_end;
307	/* Get managed bit which are not allocated */
308	bitmap_andnot(m->scratch_map, cm->managed_map, cm->alloc_map, end);
309	bit = find_first_bit(m->scratch_map, end);
310	if (bit >= end)
311		return -ENOSPC;
312	set_bit(bit, cm->alloc_map);
313	cm->allocated++;
314	cm->managed_allocated++;
315	m->total_allocated++;
316	*mapped_cpu = cpu;
317	trace_irq_matrix_alloc_managed(bit, cpu, m, cm);
318	return bit;
319}
320
321/**
322 * irq_matrix_assign - Assign a preallocated interrupt in the local CPU map
323 * @m:		Matrix pointer
324 * @bit:	Which bit to mark
325 *
326 * This should only be used to mark preallocated vectors
327 */
328void irq_matrix_assign(struct irq_matrix *m, unsigned int bit)
329{
330	struct cpumap *cm = this_cpu_ptr(m->maps);
331
332	if (WARN_ON_ONCE(bit < m->alloc_start || bit >= m->alloc_end))
333		return;
334	if (WARN_ON_ONCE(test_and_set_bit(bit, cm->alloc_map)))
335		return;
336	cm->allocated++;
337	m->total_allocated++;
338	cm->available--;
339	m->global_available--;
340	trace_irq_matrix_assign(bit, smp_processor_id(), m, cm);
341}
342
343/**
344 * irq_matrix_reserve - Reserve interrupts
345 * @m:		Matrix pointer
346 *
347 * This is merely a book keeping call. It increments the number of globally
348 * reserved interrupt bits w/o actually allocating them. This allows to
349 * setup interrupt descriptors w/o assigning low level resources to it.
350 * The actual allocation happens when the interrupt gets activated.
351 */
352void irq_matrix_reserve(struct irq_matrix *m)
353{
354	if (m->global_reserved == m->global_available)
 
355		pr_warn("Interrupt reservation exceeds available resources\n");
356
357	m->global_reserved++;
358	trace_irq_matrix_reserve(m);
359}
360
361/**
362 * irq_matrix_remove_reserved - Remove interrupt reservation
363 * @m:		Matrix pointer
364 *
365 * This is merely a book keeping call. It decrements the number of globally
366 * reserved interrupt bits. This is used to undo irq_matrix_reserve() when the
367 * interrupt was never in use and a real vector allocated, which undid the
368 * reservation.
369 */
370void irq_matrix_remove_reserved(struct irq_matrix *m)
371{
372	m->global_reserved--;
373	trace_irq_matrix_remove_reserved(m);
374}
375
376/**
377 * irq_matrix_alloc - Allocate a regular interrupt in a CPU map
378 * @m:		Matrix pointer
379 * @msk:	Which CPUs to search in
380 * @reserved:	Allocate previously reserved interrupts
381 * @mapped_cpu: Pointer to store the CPU for which the irq was allocated
382 */
383int irq_matrix_alloc(struct irq_matrix *m, const struct cpumask *msk,
384		     bool reserved, unsigned int *mapped_cpu)
385{
386	unsigned int cpu, bit;
387	struct cpumap *cm;
 
388
389	/*
390	 * Not required in theory, but matrix_find_best_cpu() uses
391	 * for_each_cpu() which ignores the cpumask on UP .
392	 */
393	if (cpumask_empty(msk))
394		return -EINVAL;
395
396	cpu = matrix_find_best_cpu(m, msk);
397	if (cpu == UINT_MAX)
398		return -ENOSPC;
399
400	cm = per_cpu_ptr(m->maps, cpu);
401	bit = matrix_alloc_area(m, cm, 1, false);
402	if (bit >= m->alloc_end)
403		return -ENOSPC;
404	cm->allocated++;
405	cm->available--;
406	m->total_allocated++;
407	m->global_available--;
408	if (reserved)
409		m->global_reserved--;
410	*mapped_cpu = cpu;
411	trace_irq_matrix_alloc(bit, cpu, m, cm);
412	return bit;
413
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
414}
415
416/**
417 * irq_matrix_free - Free allocated interrupt in the matrix
418 * @m:		Matrix pointer
419 * @cpu:	Which CPU map needs be updated
420 * @bit:	The bit to remove
421 * @managed:	If true, the interrupt is managed and not accounted
422 *		as available.
423 */
424void irq_matrix_free(struct irq_matrix *m, unsigned int cpu,
425		     unsigned int bit, bool managed)
426{
427	struct cpumap *cm = per_cpu_ptr(m->maps, cpu);
428
429	if (WARN_ON_ONCE(bit < m->alloc_start || bit >= m->alloc_end))
430		return;
431
432	if (WARN_ON_ONCE(!test_and_clear_bit(bit, cm->alloc_map)))
433		return;
434
435	cm->allocated--;
436	if(managed)
437		cm->managed_allocated--;
438
439	if (cm->online)
440		m->total_allocated--;
441
442	if (!managed) {
443		cm->available++;
444		if (cm->online)
445			m->global_available++;
446	}
447	trace_irq_matrix_free(bit, cpu, m, cm);
448}
449
450/**
451 * irq_matrix_available - Get the number of globally available irqs
452 * @m:		Pointer to the matrix to query
453 * @cpudown:	If true, the local CPU is about to go down, adjust
454 *		the number of available irqs accordingly
455 */
456unsigned int irq_matrix_available(struct irq_matrix *m, bool cpudown)
457{
458	struct cpumap *cm = this_cpu_ptr(m->maps);
459
460	if (!cpudown)
461		return m->global_available;
462	return m->global_available - cm->available;
463}
464
465/**
466 * irq_matrix_reserved - Get the number of globally reserved irqs
467 * @m:		Pointer to the matrix to query
468 */
469unsigned int irq_matrix_reserved(struct irq_matrix *m)
470{
471	return m->global_reserved;
472}
473
474/**
475 * irq_matrix_allocated - Get the number of allocated non-managed irqs on the local CPU
476 * @m:		Pointer to the matrix to search
477 *
478 * This returns number of allocated non-managed interrupts.
479 */
480unsigned int irq_matrix_allocated(struct irq_matrix *m)
481{
482	struct cpumap *cm = this_cpu_ptr(m->maps);
483
484	return cm->allocated - cm->managed_allocated;
485}
486
487#ifdef CONFIG_GENERIC_IRQ_DEBUGFS
488/**
489 * irq_matrix_debug_show - Show detailed allocation information
490 * @sf:		Pointer to the seq_file to print to
491 * @m:		Pointer to the matrix allocator
492 * @ind:	Indentation for the print format
493 *
494 * Note, this is a lockless snapshot.
495 */
496void irq_matrix_debug_show(struct seq_file *sf, struct irq_matrix *m, int ind)
497{
498	unsigned int nsys = bitmap_weight(m->system_map, m->matrix_bits);
499	int cpu;
500
501	seq_printf(sf, "Online bitmaps:   %6u\n", m->online_maps);
502	seq_printf(sf, "Global available: %6u\n", m->global_available);
503	seq_printf(sf, "Global reserved:  %6u\n", m->global_reserved);
504	seq_printf(sf, "Total allocated:  %6u\n", m->total_allocated);
505	seq_printf(sf, "System: %u: %*pbl\n", nsys, m->matrix_bits,
506		   m->system_map);
507	seq_printf(sf, "%*s| CPU | avl | man | mac | act | vectors\n", ind, " ");
508	cpus_read_lock();
509	for_each_online_cpu(cpu) {
510		struct cpumap *cm = per_cpu_ptr(m->maps, cpu);
511
512		seq_printf(sf, "%*s %4d  %4u  %4u  %4u %4u  %*pbl\n", ind, " ",
513			   cpu, cm->available, cm->managed,
514			   cm->managed_allocated, cm->allocated,
515			   m->matrix_bits, cm->alloc_map);
516	}
517	cpus_read_unlock();
518}
519#endif