1/*-
2 * Copyright (c) 2001 Wind River Systems, Inc.
3 * All rights reserved.
4 * Written by: John Baldwin <jhb@FreeBSD.org>
5 *
6 * Copyright (c) 2009 Jeffrey Roberson <jeff@freebsd.org>
7 * All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 * 4. Neither the name of the author nor the names of any co-contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34/*
35 * This module provides MI support for per-cpu data.
36 *
37 * Each architecture determines the mapping of logical CPU IDs to physical
38 * CPUs.  The requirements of this mapping are as follows:
39 *  - Logical CPU IDs must reside in the range 0 ... MAXCPU - 1.
40 *  - The mapping is not required to be dense.  That is, there may be
41 *    gaps in the mappings.
42 *  - The platform sets the value of MAXCPU in <machine/param.h>.
43 *  - It is suggested, but not required, that in the non-SMP case, the
44 *    platform define MAXCPU to be 1 and define the logical ID of the
45 *    sole CPU as 0.
46 */
47
48#include <sys/cdefs.h>
49__FBSDID("$FreeBSD$");
50
51#include "opt_ddb.h"
52
53#include <sys/param.h>
54#include <sys/systm.h>
55#include <sys/sysctl.h>
56#include <sys/lock.h>
57#include <sys/malloc.h>
58#include <sys/pcpu.h>
59#include <sys/proc.h>
60#include <sys/smp.h>
61#include <sys/sx.h>
62#include <ddb/ddb.h>
63
64static MALLOC_DEFINE(M_PCPU, "Per-cpu", "Per-cpu resource accouting.");
65
66struct dpcpu_free {
67	uintptr_t	df_start;
68	int		df_len;
69	TAILQ_ENTRY(dpcpu_free) df_link;
70};
71
72static DPCPU_DEFINE(char, modspace[DPCPU_MODMIN]);
73static TAILQ_HEAD(, dpcpu_free) dpcpu_head = TAILQ_HEAD_INITIALIZER(dpcpu_head);
74static struct sx dpcpu_lock;
75uintptr_t dpcpu_off[MAXCPU];
76struct pcpu *cpuid_to_pcpu[MAXCPU];
77struct cpuhead cpuhead = STAILQ_HEAD_INITIALIZER(cpuhead);
78
79/*
80 * Initialize the MI portions of a struct pcpu.
81 */
82void
83pcpu_init(struct pcpu *pcpu, int cpuid, size_t size)
84{
85
86	bzero(pcpu, size);
87	KASSERT(cpuid >= 0 && cpuid < MAXCPU,
88	    ("pcpu_init: invalid cpuid %d", cpuid));
89	pcpu->pc_cpuid = cpuid;
90	cpuid_to_pcpu[cpuid] = pcpu;
91	STAILQ_INSERT_TAIL(&cpuhead, pcpu, pc_allcpu);
92	cpu_pcpu_init(pcpu, cpuid, size);
93	pcpu->pc_rm_queue.rmq_next = &pcpu->pc_rm_queue;
94	pcpu->pc_rm_queue.rmq_prev = &pcpu->pc_rm_queue;
95}
96
97void
98dpcpu_init(void *dpcpu, int cpuid)
99{
100	struct pcpu *pcpu;
101
102	pcpu = pcpu_find(cpuid);
103	pcpu->pc_dynamic = (uintptr_t)dpcpu - DPCPU_START;
104
105	/*
106	 * Initialize defaults from our linker section.
107	 */
108	memcpy(dpcpu, (void *)DPCPU_START, DPCPU_BYTES);
109
110	/*
111	 * Place it in the global pcpu offset array.
112	 */
113	dpcpu_off[cpuid] = pcpu->pc_dynamic;
114}
115
116static void
117dpcpu_startup(void *dummy __unused)
118{
119	struct dpcpu_free *df;
120
121	df = malloc(sizeof(*df), M_PCPU, M_WAITOK | M_ZERO);
122	df->df_start = (uintptr_t)&DPCPU_NAME(modspace);
123	df->df_len = DPCPU_MODMIN;
124	TAILQ_INSERT_HEAD(&dpcpu_head, df, df_link);
125	sx_init(&dpcpu_lock, "dpcpu alloc lock");
126}
127SYSINIT(dpcpu, SI_SUB_KLD, SI_ORDER_FIRST, dpcpu_startup, 0);
128
129/*
130 * First-fit extent based allocator for allocating space in the per-cpu
131 * region reserved for modules.  This is only intended for use by the
132 * kernel linkers to place module linker sets.
133 */
134void *
135dpcpu_alloc(int size)
136{
137	struct dpcpu_free *df;
138	void *s;
139
140	s = NULL;
141	size = roundup2(size, sizeof(void *));
142	sx_xlock(&dpcpu_lock);
143	TAILQ_FOREACH(df, &dpcpu_head, df_link) {
144		if (df->df_len < size)
145			continue;
146		if (df->df_len == size) {
147			s = (void *)df->df_start;
148			TAILQ_REMOVE(&dpcpu_head, df, df_link);
149			free(df, M_PCPU);
150			break;
151		}
152		s = (void *)df->df_start;
153		df->df_len -= size;
154		df->df_start = df->df_start + size;
155		break;
156	}
157	sx_xunlock(&dpcpu_lock);
158
159	return (s);
160}
161
162/*
163 * Free dynamic per-cpu space at module unload time.
164 */
165void
166dpcpu_free(void *s, int size)
167{
168	struct dpcpu_free *df;
169	struct dpcpu_free *dn;
170	uintptr_t start;
171	uintptr_t end;
172
173	size = roundup2(size, sizeof(void *));
174	start = (uintptr_t)s;
175	end = start + size;
176	/*
177	 * Free a region of space and merge it with as many neighbors as
178	 * possible.  Keeping the list sorted simplifies this operation.
179	 */
180	sx_xlock(&dpcpu_lock);
181	TAILQ_FOREACH(df, &dpcpu_head, df_link) {
182		if (df->df_start > end)
183			break;
184		/*
185		 * If we expand at the end of an entry we may have to
186		 * merge it with the one following it as well.
187		 */
188		if (df->df_start + df->df_len == start) {
189			df->df_len += size;
190			dn = TAILQ_NEXT(df, df_link);
191			if (df->df_start + df->df_len == dn->df_start) {
192				df->df_len += dn->df_len;
193				TAILQ_REMOVE(&dpcpu_head, dn, df_link);
194				free(dn, M_PCPU);
195			}
196			sx_xunlock(&dpcpu_lock);
197			return;
198		}
199		if (df->df_start == end) {
200			df->df_start = start;
201			df->df_len += size;
202			sx_xunlock(&dpcpu_lock);
203			return;
204		}
205	}
206	dn = malloc(sizeof(*df), M_PCPU, M_WAITOK | M_ZERO);
207	dn->df_start = start;
208	dn->df_len = size;
209	if (df)
210		TAILQ_INSERT_BEFORE(df, dn, df_link);
211	else
212		TAILQ_INSERT_TAIL(&dpcpu_head, dn, df_link);
213	sx_xunlock(&dpcpu_lock);
214}
215
216/*
217 * Initialize the per-cpu storage from an updated linker-set region.
218 */
219void
220dpcpu_copy(void *s, int size)
221{
222#ifdef SMP
223	uintptr_t dpcpu;
224	int i;
225
226	for (i = 0; i < mp_ncpus; ++i) {
227		dpcpu = dpcpu_off[i];
228		if (dpcpu == 0)
229			continue;
230		memcpy((void *)(dpcpu + (uintptr_t)s), s, size);
231	}
232#else
233	memcpy((void *)(dpcpu_off[0] + (uintptr_t)s), s, size);
234#endif
235}
236
237/*
238 * Destroy a struct pcpu.
239 */
240void
241pcpu_destroy(struct pcpu *pcpu)
242{
243
244	STAILQ_REMOVE(&cpuhead, pcpu, pcpu, pc_allcpu);
245	cpuid_to_pcpu[pcpu->pc_cpuid] = NULL;
246	dpcpu_off[pcpu->pc_cpuid] = 0;
247}
248
249/*
250 * Locate a struct pcpu by cpu id.
251 */
252struct pcpu *
253pcpu_find(u_int cpuid)
254{
255
256	return (cpuid_to_pcpu[cpuid]);
257}
258
259int
260sysctl_dpcpu_quad(SYSCTL_HANDLER_ARGS)
261{
262	uintptr_t dpcpu;
263	int64_t count;
264	int i;
265
266	count = 0;
267	for (i = 0; i < mp_ncpus; ++i) {
268		dpcpu = dpcpu_off[i];
269		if (dpcpu == 0)
270			continue;
271		count += *(int64_t *)(dpcpu + (uintptr_t)arg1);
272	}
273	return (SYSCTL_OUT(req, &count, sizeof(count)));
274}
275
276int
277sysctl_dpcpu_long(SYSCTL_HANDLER_ARGS)
278{
279	uintptr_t dpcpu;
280	long count;
281	int i;
282
283	count = 0;
284	for (i = 0; i < mp_ncpus; ++i) {
285		dpcpu = dpcpu_off[i];
286		if (dpcpu == 0)
287			continue;
288		count += *(long *)(dpcpu + (uintptr_t)arg1);
289	}
290	return (SYSCTL_OUT(req, &count, sizeof(count)));
291}
292
293int
294sysctl_dpcpu_int(SYSCTL_HANDLER_ARGS)
295{
296	uintptr_t dpcpu;
297	int count;
298	int i;
299
300	count = 0;
301	for (i = 0; i < mp_ncpus; ++i) {
302		dpcpu = dpcpu_off[i];
303		if (dpcpu == 0)
304			continue;
305		count += *(int *)(dpcpu + (uintptr_t)arg1);
306	}
307	return (SYSCTL_OUT(req, &count, sizeof(count)));
308}
309
310#ifdef DDB
311DB_SHOW_COMMAND(dpcpu_off, db_show_dpcpu_off)
312{
313	int id;
314
315	CPU_FOREACH(id) {
316		db_printf("dpcpu_off[%2d] = 0x%jx (+ DPCPU_START = %p)\n",
317		    id, (uintmax_t)dpcpu_off[id],
318		    (void *)(uintptr_t)(dpcpu_off[id] + DPCPU_START));
319	}
320}
321
322static void
323show_pcpu(struct pcpu *pc)
324{
325	struct thread *td;
326
327	db_printf("cpuid        = %d\n", pc->pc_cpuid);
328	db_printf("dynamic pcpu = %p\n", (void *)pc->pc_dynamic);
329	db_printf("curthread    = ");
330	td = pc->pc_curthread;
331	if (td != NULL)
332		db_printf("%p: pid %d \"%s\"\n", td, td->td_proc->p_pid,
333		    td->td_name);
334	else
335		db_printf("none\n");
336	db_printf("curpcb       = %p\n", pc->pc_curpcb);
337	db_printf("fpcurthread  = ");
338	td = pc->pc_fpcurthread;
339	if (td != NULL)
340		db_printf("%p: pid %d \"%s\"\n", td, td->td_proc->p_pid,
341		    td->td_name);
342	else
343		db_printf("none\n");
344	db_printf("idlethread   = ");
345	td = pc->pc_idlethread;
346	if (td != NULL)
347		db_printf("%p: tid %d \"%s\"\n", td, td->td_tid, td->td_name);
348	else
349		db_printf("none\n");
350	db_show_mdpcpu(pc);
351
352#ifdef VIMAGE
353	db_printf("curvnet      = %p\n", pc->pc_curthread->td_vnet);
354#endif
355
356#ifdef WITNESS
357	db_printf("spin locks held:\n");
358	witness_list_locks(&pc->pc_spinlocks, db_printf);
359#endif
360}
361
362DB_SHOW_COMMAND(pcpu, db_show_pcpu)
363{
364	struct pcpu *pc;
365	int id;
366
367	if (have_addr)
368		id = ((addr >> 4) % 16) * 10 + (addr % 16);
369	else
370		id = PCPU_GET(cpuid);
371	pc = pcpu_find(id);
372	if (pc == NULL) {
373		db_printf("CPU %d not found\n", id);
374		return;
375	}
376	show_pcpu(pc);
377}
378
379DB_SHOW_ALL_COMMAND(pcpu, db_show_cpu_all)
380{
381	struct pcpu *pc;
382	int id;
383
384	db_printf("Current CPU: %d\n\n", PCPU_GET(cpuid));
385	for (id = 0; id <= mp_maxid; id++) {
386		pc = pcpu_find(id);
387		if (pc != NULL) {
388			show_pcpu(pc);
389			db_printf("\n");
390		}
391	}
392}
393DB_SHOW_ALIAS(allpcpu, db_show_cpu_all);
394#endif
395