madt: Ignore interrupt override entry if no overriding will happen
[dragonfly.git] / sys / kern / kern_slaballoc.c
CommitLineData
a108bf71 1/*
ed2013d8
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2 * (MPSAFE)
3 *
5b287bba 4 * KERN_SLABALLOC.C - Kernel SLAB memory allocator
8c10bfcf 5 *
ed2013d8 6 * Copyright (c) 2003,2004,2010 The DragonFly Project. All rights reserved.
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7 *
8 * This code is derived from software contributed to The DragonFly Project
9 * by Matthew Dillon <dillon@backplane.com>
10 *
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11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
8c10bfcf 14 *
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15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
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18 * notice, this list of conditions and the following disclaimer in
19 * the documentation and/or other materials provided with the
20 * distribution.
21 * 3. Neither the name of The DragonFly Project nor the names of its
22 * contributors may be used to endorse or promote products derived
23 * from this software without specific, prior written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
26 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
27 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
28 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
29 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
30 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
31 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
32 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
33 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
34 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
35 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
a108bf71 36 * SUCH DAMAGE.
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37 *
38 * This module implements a slab allocator drop-in replacement for the
39 * kernel malloc().
40 *
41 * A slab allocator reserves a ZONE for each chunk size, then lays the
42 * chunks out in an array within the zone. Allocation and deallocation
43 * is nearly instantanious, and fragmentation/overhead losses are limited
44 * to a fixed worst-case amount.
45 *
46 * The downside of this slab implementation is in the chunk size
47 * multiplied by the number of zones. ~80 zones * 128K = 10MB of VM per cpu.
48 * In a kernel implementation all this memory will be physical so
49 * the zone size is adjusted downward on machines with less physical
50 * memory. The upside is that overhead is bounded... this is the *worst*
51 * case overhead.
52 *
53 * Slab management is done on a per-cpu basis and no locking or mutexes
54 * are required, only a critical section. When one cpu frees memory
55 * belonging to another cpu's slab manager an asynchronous IPI message
56 * will be queued to execute the operation. In addition, both the
57 * high level slab allocator and the low level zone allocator optimize
58 * M_ZERO requests, and the slab allocator does not have to pre initialize
59 * the linked list of chunks.
60 *
61 * XXX Balancing is needed between cpus. Balance will be handled through
62 * asynchronous IPIs primarily by reassigning the z_Cpu ownership of chunks.
63 *
64 * XXX If we have to allocate a new zone and M_USE_RESERVE is set, use of
65 * the new zone should be restricted to M_USE_RESERVE requests only.
66 *
67 * Alloc Size Chunking Number of zones
68 * 0-127 8 16
69 * 128-255 16 8
70 * 256-511 32 8
71 * 512-1023 64 8
72 * 1024-2047 128 8
73 * 2048-4095 256 8
74 * 4096-8191 512 8
75 * 8192-16383 1024 8
76 * 16384-32767 2048 8
77 * (if PAGE_SIZE is 4K the maximum zone allocation is 16383)
78 *
46a3f46d 79 * Allocations >= ZoneLimit go directly to kmem.
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80 *
81 * API REQUIREMENTS AND SIDE EFFECTS
82 *
83 * To operate as a drop-in replacement to the FreeBSD-4.x malloc() we
84 * have remained compatible with the following API requirements:
85 *
86 * + small power-of-2 sized allocations are power-of-2 aligned (kern_tty)
3d177b31 87 * + all power-of-2 sized allocations are power-of-2 aligned (twe)
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88 * + malloc(0) is allowed and returns non-NULL (ahc driver)
89 * + ability to allocate arbitrarily large chunks of memory
90 */
91
92#include "opt_vm.h"
93
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94#include <sys/param.h>
95#include <sys/systm.h>
96#include <sys/kernel.h>
97#include <sys/slaballoc.h>
98#include <sys/mbuf.h>
99#include <sys/vmmeter.h>
100#include <sys/lock.h>
101#include <sys/thread.h>
102#include <sys/globaldata.h>
d2182dc1 103#include <sys/sysctl.h>
f2b5daf9 104#include <sys/ktr.h>
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105
106#include <vm/vm.h>
107#include <vm/vm_param.h>
108#include <vm/vm_kern.h>
109#include <vm/vm_extern.h>
110#include <vm/vm_object.h>
111#include <vm/pmap.h>
112#include <vm/vm_map.h>
113#include <vm/vm_page.h>
114#include <vm/vm_pageout.h>
115
116#include <machine/cpu.h>
117
118#include <sys/thread2.h>
119
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120#define btokup(z) (&pmap_kvtom((vm_offset_t)(z))->ku_pagecnt)
121
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122#define MEMORY_STRING "ptr=%p type=%p size=%d flags=%04x"
123#define MEMORY_ARG_SIZE (sizeof(void *) * 2 + sizeof(unsigned long) + \
124 sizeof(int))
125
126#if !defined(KTR_MEMORY)
127#define KTR_MEMORY KTR_ALL
128#endif
129KTR_INFO_MASTER(memory);
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130KTR_INFO(KTR_MEMORY, memory, malloc_beg, 0, "malloc begin", 0);
131KTR_INFO(KTR_MEMORY, memory, malloc_end, 1, MEMORY_STRING, MEMORY_ARG_SIZE);
132KTR_INFO(KTR_MEMORY, memory, free_zero, 2, MEMORY_STRING, MEMORY_ARG_SIZE);
133KTR_INFO(KTR_MEMORY, memory, free_ovsz, 3, MEMORY_STRING, MEMORY_ARG_SIZE);
134KTR_INFO(KTR_MEMORY, memory, free_ovsz_delayed, 4, MEMORY_STRING, MEMORY_ARG_SIZE);
135KTR_INFO(KTR_MEMORY, memory, free_chunk, 5, MEMORY_STRING, MEMORY_ARG_SIZE);
f2b5daf9 136#ifdef SMP
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137KTR_INFO(KTR_MEMORY, memory, free_request, 6, MEMORY_STRING, MEMORY_ARG_SIZE);
138KTR_INFO(KTR_MEMORY, memory, free_rem_beg, 7, MEMORY_STRING, MEMORY_ARG_SIZE);
139KTR_INFO(KTR_MEMORY, memory, free_rem_end, 8, MEMORY_STRING, MEMORY_ARG_SIZE);
f2b5daf9 140#endif
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141KTR_INFO(KTR_MEMORY, memory, free_beg, 9, "free begin", 0);
142KTR_INFO(KTR_MEMORY, memory, free_end, 10, "free end", 0);
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143
144#define logmemory(name, ptr, type, size, flags) \
145 KTR_LOG(memory_ ## name, ptr, type, size, flags)
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146#define logmemory_quick(name) \
147 KTR_LOG(memory_ ## name)
f2b5daf9 148
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149/*
150 * Fixed globals (not per-cpu)
151 */
152static int ZoneSize;
46a3f46d 153static int ZoneLimit;
a108bf71 154static int ZonePageCount;
5fee07e6 155static uintptr_t ZoneMask;
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156static int ZoneBigAlloc; /* in KB */
157static int ZoneGenAlloc; /* in KB */
460426e6 158struct malloc_type *kmemstatistics; /* exported to vmstat */
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159static int32_t weirdary[16];
160
161static void *kmem_slab_alloc(vm_size_t bytes, vm_offset_t align, int flags);
162static void kmem_slab_free(void *ptr, vm_size_t bytes);
5fee07e6 163
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164#if defined(INVARIANTS)
165static void chunk_mark_allocated(SLZone *z, void *chunk);
166static void chunk_mark_free(SLZone *z, void *chunk);
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167#else
168#define chunk_mark_allocated(z, chunk)
169#define chunk_mark_free(z, chunk)
10cc6608 170#endif
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171
172/*
173 * Misc constants. Note that allocations that are exact multiples of
174 * PAGE_SIZE, or exceed the zone limit, fall through to the kmem module.
175 * IN_SAME_PAGE_MASK is used to sanity-check the per-page free lists.
176 */
177#define MIN_CHUNK_SIZE 8 /* in bytes */
178#define MIN_CHUNK_MASK (MIN_CHUNK_SIZE - 1)
179#define ZONE_RELS_THRESH 2 /* threshold number of zones */
180#define IN_SAME_PAGE_MASK (~(intptr_t)PAGE_MASK | MIN_CHUNK_MASK)
181
182/*
183 * The WEIRD_ADDR is used as known text to copy into free objects to
184 * try to create deterministic failure cases if the data is accessed after
185 * free.
186 */
187#define WEIRD_ADDR 0xdeadc0de
188#define MAX_COPY sizeof(weirdary)
189#define ZERO_LENGTH_PTR ((void *)-8)
190
191/*
192 * Misc global malloc buckets
193 */
194
195MALLOC_DEFINE(M_CACHE, "cache", "Various Dynamically allocated caches");
196MALLOC_DEFINE(M_DEVBUF, "devbuf", "device driver memory");
197MALLOC_DEFINE(M_TEMP, "temp", "misc temporary data buffers");
198
199MALLOC_DEFINE(M_IP6OPT, "ip6opt", "IPv6 options");
200MALLOC_DEFINE(M_IP6NDP, "ip6ndp", "IPv6 Neighbor Discovery");
201
202/*
203 * Initialize the slab memory allocator. We have to choose a zone size based
204 * on available physical memory. We choose a zone side which is approximately
205 * 1/1024th of our memory, so if we have 128MB of ram we have a zone size of
206 * 128K. The zone size is limited to the bounds set in slaballoc.h
207 * (typically 32K min, 128K max).
208 */
209static void kmeminit(void *dummy);
210
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211char *ZeroPage;
212
ba39e2e0 213SYSINIT(kmem, SI_BOOT1_ALLOCATOR, SI_ORDER_FIRST, kmeminit, NULL)
a108bf71 214
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215#ifdef INVARIANTS
216/*
217 * If enabled any memory allocated without M_ZERO is initialized to -1.
218 */
219static int use_malloc_pattern;
220SYSCTL_INT(_debug, OID_AUTO, use_malloc_pattern, CTLFLAG_RW,
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221 &use_malloc_pattern, 0,
222 "Initialize memory to -1 if M_ZERO not specified");
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223#endif
224
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225SYSCTL_INT(_kern, OID_AUTO, zone_big_alloc, CTLFLAG_RD, &ZoneBigAlloc, 0, "");
226SYSCTL_INT(_kern, OID_AUTO, zone_gen_alloc, CTLFLAG_RD, &ZoneGenAlloc, 0, "");
227
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228static void
229kmeminit(void *dummy)
230{
7c457ac8 231 size_t limsize;
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232 int usesize;
233 int i;
a108bf71 234
7c457ac8 235 limsize = (size_t)vmstats.v_page_count * PAGE_SIZE;
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236 if (limsize > KvaSize)
237 limsize = KvaSize;
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238
239 usesize = (int)(limsize / 1024); /* convert to KB */
240
241 ZoneSize = ZALLOC_MIN_ZONE_SIZE;
242 while (ZoneSize < ZALLOC_MAX_ZONE_SIZE && (ZoneSize << 1) < usesize)
243 ZoneSize <<= 1;
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244 ZoneLimit = ZoneSize / 4;
245 if (ZoneLimit > ZALLOC_ZONE_LIMIT)
246 ZoneLimit = ZALLOC_ZONE_LIMIT;
5fee07e6 247 ZoneMask = ~(uintptr_t)(ZoneSize - 1);
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248 ZonePageCount = ZoneSize / PAGE_SIZE;
249
a3034532 250 for (i = 0; i < NELEM(weirdary); ++i)
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251 weirdary[i] = WEIRD_ADDR;
252
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253 ZeroPage = kmem_slab_alloc(PAGE_SIZE, PAGE_SIZE, M_WAITOK|M_ZERO);
254
a108bf71 255 if (bootverbose)
6ea70f76 256 kprintf("Slab ZoneSize set to %dKB\n", ZoneSize / 1024);
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257}
258
259/*
bba6a44d 260 * Initialize a malloc type tracking structure.
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261 */
262void
263malloc_init(void *data)
264{
265 struct malloc_type *type = data;
7c457ac8 266 size_t limsize;
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267
268 if (type->ks_magic != M_MAGIC)
269 panic("malloc type lacks magic");
270
271 if (type->ks_limit != 0)
272 return;
273
274 if (vmstats.v_page_count == 0)
275 panic("malloc_init not allowed before vm init");
276
7c457ac8 277 limsize = (size_t)vmstats.v_page_count * PAGE_SIZE;
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278 if (limsize > KvaSize)
279 limsize = KvaSize;
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280 type->ks_limit = limsize / 10;
281
282 type->ks_next = kmemstatistics;
283 kmemstatistics = type;
284}
285
286void
287malloc_uninit(void *data)
288{
289 struct malloc_type *type = data;
290 struct malloc_type *t;
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291#ifdef INVARIANTS
292 int i;
1d712609 293 long ttl;
bba6a44d 294#endif
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295
296 if (type->ks_magic != M_MAGIC)
297 panic("malloc type lacks magic");
298
299 if (vmstats.v_page_count == 0)
300 panic("malloc_uninit not allowed before vm init");
301
302 if (type->ks_limit == 0)
303 panic("malloc_uninit on uninitialized type");
304
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305#ifdef SMP
306 /* Make sure that all pending kfree()s are finished. */
307 lwkt_synchronize_ipiqs("muninit");
308#endif
309
a108bf71 310#ifdef INVARIANTS
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311 /*
312 * memuse is only correct in aggregation. Due to memory being allocated
313 * on one cpu and freed on another individual array entries may be
314 * negative or positive (canceling each other out).
315 */
316 for (i = ttl = 0; i < ncpus; ++i)
317 ttl += type->ks_memuse[i];
318 if (ttl) {
6ea70f76 319 kprintf("malloc_uninit: %ld bytes of '%s' still allocated on cpu %d\n",
1d712609 320 ttl, type->ks_shortdesc, i);
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321 }
322#endif
323 if (type == kmemstatistics) {
324 kmemstatistics = type->ks_next;
325 } else {
326 for (t = kmemstatistics; t->ks_next != NULL; t = t->ks_next) {
327 if (t->ks_next == type) {
328 t->ks_next = type->ks_next;
329 break;
330 }
331 }
332 }
333 type->ks_next = NULL;
334 type->ks_limit = 0;
335}
336
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337/*
338 * Increase the kmalloc pool limit for the specified pool. No changes
339 * are the made if the pool would shrink.
340 */
341void
342kmalloc_raise_limit(struct malloc_type *type, size_t bytes)
343{
344 if (type->ks_limit == 0)
345 malloc_init(type);
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346 if (bytes == 0)
347 bytes = KvaSize;
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348 if (type->ks_limit < bytes)
349 type->ks_limit = bytes;
350}
351
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352/*
353 * Dynamically create a malloc pool. This function is a NOP if *typep is
354 * already non-NULL.
355 */
356void
357kmalloc_create(struct malloc_type **typep, const char *descr)
358{
359 struct malloc_type *type;
360
361 if (*typep == NULL) {
362 type = kmalloc(sizeof(*type), M_TEMP, M_WAITOK | M_ZERO);
363 type->ks_magic = M_MAGIC;
364 type->ks_shortdesc = descr;
365 malloc_init(type);
366 *typep = type;
367 }
368}
369
370/*
371 * Destroy a dynamically created malloc pool. This function is a NOP if
372 * the pool has already been destroyed.
373 */
374void
375kmalloc_destroy(struct malloc_type **typep)
376{
377 if (*typep != NULL) {
378 malloc_uninit(*typep);
379 kfree(*typep, M_TEMP);
380 *typep = NULL;
381 }
382}
383
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384/*
385 * Calculate the zone index for the allocation request size and set the
386 * allocation request size to that particular zone's chunk size.
387 */
388static __inline int
389zoneindex(unsigned long *bytes)
390{
391 unsigned int n = (unsigned int)*bytes; /* unsigned for shift opt */
392 if (n < 128) {
393 *bytes = n = (n + 7) & ~7;
394 return(n / 8 - 1); /* 8 byte chunks, 16 zones */
395 }
396 if (n < 256) {
397 *bytes = n = (n + 15) & ~15;
398 return(n / 16 + 7);
399 }
400 if (n < 8192) {
401 if (n < 512) {
402 *bytes = n = (n + 31) & ~31;
403 return(n / 32 + 15);
404 }
405 if (n < 1024) {
406 *bytes = n = (n + 63) & ~63;
407 return(n / 64 + 23);
408 }
409 if (n < 2048) {
410 *bytes = n = (n + 127) & ~127;
411 return(n / 128 + 31);
412 }
413 if (n < 4096) {
414 *bytes = n = (n + 255) & ~255;
415 return(n / 256 + 39);
416 }
417 *bytes = n = (n + 511) & ~511;
418 return(n / 512 + 47);
419 }
420#if ZALLOC_ZONE_LIMIT > 8192
421 if (n < 16384) {
422 *bytes = n = (n + 1023) & ~1023;
423 return(n / 1024 + 55);
424 }
425#endif
426#if ZALLOC_ZONE_LIMIT > 16384
427 if (n < 32768) {
428 *bytes = n = (n + 2047) & ~2047;
429 return(n / 2048 + 63);
430 }
431#endif
432 panic("Unexpected byte count %d", n);
433 return(0);
434}
435
436/*
5fee07e6 437 * kmalloc() (SLAB ALLOCATOR)
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438 *
439 * Allocate memory via the slab allocator. If the request is too large,
440 * or if it page-aligned beyond a certain size, we fall back to the
441 * KMEM subsystem. A SLAB tracking descriptor must be specified, use
442 * &SlabMisc if you don't care.
443 *
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444 * M_RNOWAIT - don't block.
445 * M_NULLOK - return NULL instead of blocking.
a108bf71 446 * M_ZERO - zero the returned memory.
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447 * M_USE_RESERVE - allow greater drawdown of the free list
448 * M_USE_INTERRUPT_RESERVE - allow the freelist to be exhausted
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449 *
450 * MPSAFE
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451 */
452void *
8aca2bd4 453kmalloc(unsigned long size, struct malloc_type *type, int flags)
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454{
455 SLZone *z;
456 SLChunk *chunk;
d8100bdc 457#ifdef SMP
5fee07e6 458 SLChunk *bchunk;
d8100bdc 459#endif
a108bf71 460 SLGlobalData *slgd;
bba6a44d 461 struct globaldata *gd;
a108bf71 462 int zi;
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463#ifdef INVARIANTS
464 int i;
465#endif
a108bf71 466
b68ad50c 467 logmemory_quick(malloc_beg);
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468 gd = mycpu;
469 slgd = &gd->gd_slab;
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470
471 /*
472 * XXX silly to have this in the critical path.
473 */
474 if (type->ks_limit == 0) {
475 crit_enter();
476 if (type->ks_limit == 0)
477 malloc_init(type);
478 crit_exit();
479 }
480 ++type->ks_calls;
481
482 /*
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483 * Handle the case where the limit is reached. Panic if we can't return
484 * NULL. The original malloc code looped, but this tended to
a108bf71 485 * simply deadlock the computer.
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486 *
487 * ks_loosememuse is an up-only limit that is NOT MP-synchronized, used
488 * to determine if a more complete limit check should be done. The
489 * actual memory use is tracked via ks_memuse[cpu].
a108bf71 490 */
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491 while (type->ks_loosememuse >= type->ks_limit) {
492 int i;
493 long ttl;
494
495 for (i = ttl = 0; i < ncpus; ++i)
496 ttl += type->ks_memuse[i];
38e34349 497 type->ks_loosememuse = ttl; /* not MP synchronized */
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498 if ((ssize_t)ttl < 0) /* deal with occassional race */
499 ttl = 0;
bba6a44d 500 if (ttl >= type->ks_limit) {
f2b5daf9 501 if (flags & M_NULLOK) {
5fee07e6 502 logmemory(malloc_end, NULL, type, size, flags);
bba6a44d 503 return(NULL);
f2b5daf9 504 }
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505 panic("%s: malloc limit exceeded", type->ks_shortdesc);
506 }
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507 }
508
509 /*
510 * Handle the degenerate size == 0 case. Yes, this does happen.
511 * Return a special pointer. This is to maintain compatibility with
512 * the original malloc implementation. Certain devices, such as the
513 * adaptec driver, not only allocate 0 bytes, they check for NULL and
514 * also realloc() later on. Joy.
515 */
f2b5daf9 516 if (size == 0) {
5fee07e6 517 logmemory(malloc_end, ZERO_LENGTH_PTR, type, size, flags);
a108bf71 518 return(ZERO_LENGTH_PTR);
f2b5daf9 519 }
a108bf71 520
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521 /*
522 * Handle hysteresis from prior frees here in malloc(). We cannot
523 * safely manipulate the kernel_map in free() due to free() possibly
524 * being called via an IPI message or from sensitive interrupt code.
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525 *
526 * NOTE: ku_pagecnt must be cleared before we free the slab or we
527 * might race another cpu allocating the kva and setting
528 * ku_pagecnt.
a7cf0021 529 */
dc1fd4b3 530 while (slgd->NFreeZones > ZONE_RELS_THRESH && (flags & M_RNOWAIT) == 0) {
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531 crit_enter();
532 if (slgd->NFreeZones > ZONE_RELS_THRESH) { /* crit sect race */
722871d3 533 int *kup;
5fee07e6 534
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535 z = slgd->FreeZones;
536 slgd->FreeZones = z->z_Next;
537 --slgd->NFreeZones;
5fee07e6 538 kup = btokup(z);
722871d3 539 *kup = 0;
46a3f46d 540 kmem_slab_free(z, ZoneSize); /* may block */
665206ee 541 atomic_add_int(&ZoneGenAlloc, -(int)ZoneSize / 1024);
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MD
542 }
543 crit_exit();
544 }
5fee07e6 545
46a3f46d 546 /*
5fee07e6 547 * XXX handle oversized frees that were queued from kfree().
46a3f46d 548 */
dc1fd4b3 549 while (slgd->FreeOvZones && (flags & M_RNOWAIT) == 0) {
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550 crit_enter();
551 if ((z = slgd->FreeOvZones) != NULL) {
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552 vm_size_t tsize;
553
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554 KKASSERT(z->z_Magic == ZALLOC_OVSZ_MAGIC);
555 slgd->FreeOvZones = z->z_Next;
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556 tsize = z->z_ChunkSize;
557 kmem_slab_free(z, tsize); /* may block */
558 atomic_add_int(&ZoneBigAlloc, -(int)tsize / 1024);
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559 }
560 crit_exit();
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561 }
562
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563 /*
564 * Handle large allocations directly. There should not be very many of
565 * these so performance is not a big issue.
566 *
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567 * The backend allocator is pretty nasty on a SMP system. Use the
568 * slab allocator for one and two page-sized chunks even though we lose
569 * some efficiency. XXX maybe fix mmio and the elf loader instead.
a108bf71 570 */
b543eeed 571 if (size >= ZoneLimit || ((size & PAGE_MASK) == 0 && size > PAGE_SIZE*2)) {
722871d3 572 int *kup;
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573
574 size = round_page(size);
575 chunk = kmem_slab_alloc(size, PAGE_SIZE, flags);
f2b5daf9 576 if (chunk == NULL) {
5fee07e6 577 logmemory(malloc_end, NULL, type, size, flags);
a108bf71 578 return(NULL);
f2b5daf9 579 }
665206ee 580 atomic_add_int(&ZoneBigAlloc, (int)size / 1024);
a108bf71 581 flags &= ~M_ZERO; /* result already zero'd if M_ZERO was set */
8f1d5415 582 flags |= M_PASSIVE_ZERO;
a108bf71 583 kup = btokup(chunk);
722871d3 584 *kup = size / PAGE_SIZE;
a108bf71
MD
585 crit_enter();
586 goto done;
587 }
588
589 /*
590 * Attempt to allocate out of an existing zone. First try the free list,
591 * then allocate out of unallocated space. If we find a good zone move
592 * it to the head of the list so later allocations find it quickly
593 * (we might have thousands of zones in the list).
594 *
595 * Note: zoneindex() will panic of size is too large.
596 */
597 zi = zoneindex(&size);
598 KKASSERT(zi < NZONES);
599 crit_enter();
a108bf71 600
5fee07e6 601 if ((z = slgd->ZoneAry[zi]) != NULL) {
a108bf71 602 /*
5fee07e6
MD
603 * Locate a chunk - we have to have at least one. If this is the
604 * last chunk go ahead and do the work to retrieve chunks freed
605 * from remote cpus, and if the zone is still empty move it off
606 * the ZoneAry.
a108bf71 607 */
5fee07e6
MD
608 if (--z->z_NFree <= 0) {
609 KKASSERT(z->z_NFree == 0);
610
611#ifdef SMP
612 /*
613 * WARNING! This code competes with other cpus. It is ok
614 * for us to not drain RChunks here but we might as well, and
615 * it is ok if more accumulate after we're done.
616 *
617 * Set RSignal before pulling rchunks off, indicating that we
618 * will be moving ourselves off of the ZoneAry. Remote ends will
619 * read RSignal before putting rchunks on thus interlocking
620 * their IPI signaling.
621 */
622 if (z->z_RChunks == NULL)
623 atomic_swap_int(&z->z_RSignal, 1);
624
625 while ((bchunk = z->z_RChunks) != NULL) {
626 cpu_ccfence();
627 if (atomic_cmpset_ptr(&z->z_RChunks, bchunk, NULL)) {
628 *z->z_LChunksp = bchunk;
629 while (bchunk) {
630 chunk_mark_free(z, bchunk);
631 z->z_LChunksp = &bchunk->c_Next;
632 bchunk = bchunk->c_Next;
633 ++z->z_NFree;
634 }
635 break;
636 }
637 }
638#endif
639 /*
640 * Remove from the zone list if no free chunks remain.
641 * Clear RSignal
642 */
643 if (z->z_NFree == 0) {
644 slgd->ZoneAry[zi] = z->z_Next;
645 z->z_Next = NULL;
646 } else {
647 z->z_RSignal = 0;
648 }
a108bf71
MD
649 }
650
651 /*
5fee07e6 652 * Fast path, we have chunks available in z_LChunks.
a108bf71 653 */
5fee07e6
MD
654 chunk = z->z_LChunks;
655 if (chunk) {
10cc6608 656 chunk_mark_allocated(z, chunk);
5fee07e6
MD
657 z->z_LChunks = chunk->c_Next;
658 if (z->z_LChunks == NULL)
659 z->z_LChunksp = &z->z_LChunks;
a108bf71 660 goto done;
a108bf71
MD
661 }
662
663 /*
5fee07e6
MD
664 * No chunks are available in LChunks, the free chunk MUST be
665 * in the never-before-used memory area, controlled by UIndex.
666 *
667 * The consequences are very serious if our zone got corrupted so
668 * we use an explicit panic rather than a KASSERT.
a108bf71 669 */
1c5ca4f3 670 if (z->z_UIndex + 1 != z->z_NMax)
5fee07e6 671 ++z->z_UIndex;
1c5ca4f3
MD
672 else
673 z->z_UIndex = 0;
5fee07e6 674
1c5ca4f3
MD
675 if (z->z_UIndex == z->z_UEndIndex)
676 panic("slaballoc: corrupted zone");
5fee07e6 677
1c5ca4f3 678 chunk = (SLChunk *)(z->z_BasePtr + z->z_UIndex * size);
8f1d5415 679 if ((z->z_Flags & SLZF_UNOTZEROD) == 0) {
6ab8e1da 680 flags &= ~M_ZERO;
8f1d5415
MD
681 flags |= M_PASSIVE_ZERO;
682 }
10cc6608 683 chunk_mark_allocated(z, chunk);
a108bf71
MD
684 goto done;
685 }
686
687 /*
688 * If all zones are exhausted we need to allocate a new zone for this
689 * index. Use M_ZERO to take advantage of pre-zerod pages. Also see
6ab8e1da
MD
690 * UAlloc use above in regards to M_ZERO. Note that when we are reusing
691 * a zone from the FreeZones list UAlloc'd data will not be zero'd, and
692 * we do not pre-zero it because we do not want to mess up the L1 cache.
a108bf71
MD
693 *
694 * At least one subsystem, the tty code (see CROUND) expects power-of-2
695 * allocations to be power-of-2 aligned. We maintain compatibility by
696 * adjusting the base offset below.
697 */
698 {
699 int off;
722871d3 700 int *kup;
a108bf71
MD
701
702 if ((z = slgd->FreeZones) != NULL) {
703 slgd->FreeZones = z->z_Next;
704 --slgd->NFreeZones;
705 bzero(z, sizeof(SLZone));
6ab8e1da 706 z->z_Flags |= SLZF_UNOTZEROD;
a108bf71
MD
707 } else {
708 z = kmem_slab_alloc(ZoneSize, ZoneSize, flags|M_ZERO);
709 if (z == NULL)
710 goto fail;
665206ee 711 atomic_add_int(&ZoneGenAlloc, (int)ZoneSize / 1024);
a108bf71
MD
712 }
713
10cc6608
MD
714 /*
715 * How big is the base structure?
716 */
717#if defined(INVARIANTS)
718 /*
719 * Make room for z_Bitmap. An exact calculation is somewhat more
720 * complicated so don't make an exact calculation.
721 */
722 off = offsetof(SLZone, z_Bitmap[(ZoneSize / size + 31) / 32]);
723 bzero(z->z_Bitmap, (ZoneSize / size + 31) / 8);
724#else
725 off = sizeof(SLZone);
726#endif
727
a108bf71
MD
728 /*
729 * Guarentee power-of-2 alignment for power-of-2-sized chunks.
730 * Otherwise just 8-byte align the data.
731 */
732 if ((size | (size - 1)) + 1 == (size << 1))
10cc6608 733 off = (off + size - 1) & ~(size - 1);
a108bf71 734 else
10cc6608 735 off = (off + MIN_CHUNK_MASK) & ~MIN_CHUNK_MASK;
a108bf71
MD
736 z->z_Magic = ZALLOC_SLAB_MAGIC;
737 z->z_ZoneIndex = zi;
738 z->z_NMax = (ZoneSize - off) / size;
739 z->z_NFree = z->z_NMax - 1;
1c5ca4f3
MD
740 z->z_BasePtr = (char *)z + off;
741 z->z_UIndex = z->z_UEndIndex = slgd->JunkIndex % z->z_NMax;
a108bf71 742 z->z_ChunkSize = size;
2db3b277 743 z->z_CpuGd = gd;
bba6a44d 744 z->z_Cpu = gd->gd_cpuid;
5fee07e6 745 z->z_LChunksp = &z->z_LChunks;
1c5ca4f3 746 chunk = (SLChunk *)(z->z_BasePtr + z->z_UIndex * size);
a108bf71
MD
747 z->z_Next = slgd->ZoneAry[zi];
748 slgd->ZoneAry[zi] = z;
8f1d5415 749 if ((z->z_Flags & SLZF_UNOTZEROD) == 0) {
6ab8e1da 750 flags &= ~M_ZERO; /* already zero'd */
8f1d5415
MD
751 flags |= M_PASSIVE_ZERO;
752 }
5fee07e6 753 kup = btokup(z);
722871d3 754 *kup = -(z->z_Cpu + 1); /* -1 to -(N+1) */
10cc6608 755 chunk_mark_allocated(z, chunk);
1c5ca4f3
MD
756
757 /*
758 * Slide the base index for initial allocations out of the next
759 * zone we create so we do not over-weight the lower part of the
760 * cpu memory caches.
761 */
762 slgd->JunkIndex = (slgd->JunkIndex + ZALLOC_SLAB_SLIDE)
763 & (ZALLOC_MAX_ZONE_SIZE - 1);
a108bf71 764 }
5fee07e6 765
a108bf71 766done:
bba6a44d
MD
767 ++type->ks_inuse[gd->gd_cpuid];
768 type->ks_memuse[gd->gd_cpuid] += size;
38e34349 769 type->ks_loosememuse += size; /* not MP synchronized */
a108bf71 770 crit_exit();
5fee07e6 771
a108bf71
MD
772 if (flags & M_ZERO)
773 bzero(chunk, size);
bba6a44d 774#ifdef INVARIANTS
d2182dc1
MD
775 else if ((flags & (M_ZERO|M_PASSIVE_ZERO)) == 0) {
776 if (use_malloc_pattern) {
777 for (i = 0; i < size; i += sizeof(int)) {
778 *(int *)((char *)chunk + i) = -1;
779 }
780 }
bba6a44d 781 chunk->c_Next = (void *)-1; /* avoid accidental double-free check */
d2182dc1 782 }
bba6a44d 783#endif
5fee07e6 784 logmemory(malloc_end, chunk, type, size, flags);
a108bf71
MD
785 return(chunk);
786fail:
787 crit_exit();
5fee07e6 788 logmemory(malloc_end, NULL, type, size, flags);
a108bf71
MD
789 return(NULL);
790}
791
38e34349
MD
792/*
793 * kernel realloc. (SLAB ALLOCATOR) (MP SAFE)
794 *
795 * Generally speaking this routine is not called very often and we do
796 * not attempt to optimize it beyond reusing the same pointer if the
797 * new size fits within the chunking of the old pointer's zone.
798 */
a108bf71 799void *
8aca2bd4 800krealloc(void *ptr, unsigned long size, struct malloc_type *type, int flags)
a108bf71 801{
722871d3 802 unsigned long osize;
a108bf71
MD
803 SLZone *z;
804 void *nptr;
722871d3 805 int *kup;
a108bf71 806
eb7f3e3c
MD
807 KKASSERT((flags & M_ZERO) == 0); /* not supported */
808
a108bf71 809 if (ptr == NULL || ptr == ZERO_LENGTH_PTR)
efda3bd0 810 return(kmalloc(size, type, flags));
a108bf71 811 if (size == 0) {
efda3bd0 812 kfree(ptr, type);
a108bf71
MD
813 return(NULL);
814 }
815
816 /*
817 * Handle oversized allocations. XXX we really should require that a
818 * size be passed to free() instead of this nonsense.
819 */
5fee07e6 820 kup = btokup(ptr);
722871d3
MD
821 if (*kup > 0) {
822 osize = *kup << PAGE_SHIFT;
5fee07e6
MD
823 if (osize == round_page(size))
824 return(ptr);
825 if ((nptr = kmalloc(size, type, flags)) == NULL)
826 return(NULL);
827 bcopy(ptr, nptr, min(size, osize));
828 kfree(ptr, type);
829 return(nptr);
a108bf71
MD
830 }
831
832 /*
833 * Get the original allocation's zone. If the new request winds up
834 * using the same chunk size we do not have to do anything.
835 */
5fee07e6
MD
836 z = (SLZone *)((uintptr_t)ptr & ZoneMask);
837 kup = btokup(z);
722871d3 838 KKASSERT(*kup < 0);
a108bf71
MD
839 KKASSERT(z->z_Magic == ZALLOC_SLAB_MAGIC);
840
a108bf71
MD
841 /*
842 * Allocate memory for the new request size. Note that zoneindex has
843 * already adjusted the request size to the appropriate chunk size, which
844 * should optimize our bcopy(). Then copy and return the new pointer.
1ea6580d
MD
845 *
846 * Resizing a non-power-of-2 allocation to a power-of-2 size does not
847 * necessary align the result.
848 *
849 * We can only zoneindex (to align size to the chunk size) if the new
850 * size is not too large.
a108bf71 851 */
1ea6580d
MD
852 if (size < ZoneLimit) {
853 zoneindex(&size);
854 if (z->z_ChunkSize == size)
855 return(ptr);
856 }
efda3bd0 857 if ((nptr = kmalloc(size, type, flags)) == NULL)
a108bf71
MD
858 return(NULL);
859 bcopy(ptr, nptr, min(size, z->z_ChunkSize));
efda3bd0 860 kfree(ptr, type);
a108bf71
MD
861 return(nptr);
862}
863
45d2b1d8
MD
864/*
865 * Return the kmalloc limit for this type, in bytes.
866 */
867long
868kmalloc_limit(struct malloc_type *type)
869{
870 if (type->ks_limit == 0) {
871 crit_enter();
872 if (type->ks_limit == 0)
873 malloc_init(type);
874 crit_exit();
875 }
876 return(type->ks_limit);
877}
878
38e34349
MD
879/*
880 * Allocate a copy of the specified string.
881 *
882 * (MP SAFE) (MAY BLOCK)
883 */
1ac06773 884char *
59302080 885kstrdup(const char *str, struct malloc_type *type)
1ac06773
MD
886{
887 int zlen; /* length inclusive of terminating NUL */
888 char *nstr;
889
890 if (str == NULL)
891 return(NULL);
892 zlen = strlen(str) + 1;
efda3bd0 893 nstr = kmalloc(zlen, type, M_WAITOK);
1ac06773
MD
894 bcopy(str, nstr, zlen);
895 return(nstr);
896}
897
1d712609 898#ifdef SMP
a108bf71 899/*
5fee07e6 900 * Notify our cpu that a remote cpu has freed some chunks in a zone that
df9daea8
MD
901 * we own. RCount will be bumped so the memory should be good, but validate
902 * that it really is.
a108bf71
MD
903 */
904static
905void
5fee07e6 906kfree_remote(void *ptr)
a108bf71 907{
5fee07e6
MD
908 SLGlobalData *slgd;
909 SLChunk *bchunk;
910 SLZone *z;
911 int nfree;
722871d3 912 int *kup;
5fee07e6 913
5fee07e6
MD
914 slgd = &mycpu->gd_slab;
915 z = ptr;
916 kup = btokup(z);
df9daea8
MD
917 KKASSERT(*kup == -((int)mycpuid + 1));
918 KKASSERT(z->z_RCount > 0);
919 atomic_subtract_int(&z->z_RCount, 1);
5fee07e6 920
df9daea8
MD
921 logmemory(free_rem_beg, z, NULL, 0, 0);
922 KKASSERT(z->z_Magic == ZALLOC_SLAB_MAGIC);
923 KKASSERT(z->z_Cpu == mycpu->gd_cpuid);
924 nfree = z->z_NFree;
5fee07e6 925
df9daea8
MD
926 /*
927 * Indicate that we will no longer be off of the ZoneAry by
928 * clearing RSignal.
929 */
930 if (z->z_RChunks)
931 z->z_RSignal = 0;
5fee07e6 932
df9daea8
MD
933 /*
934 * Atomically extract the bchunks list and then process it back
935 * into the lchunks list. We want to append our bchunks to the
936 * lchunks list and not prepend since we likely do not have
937 * cache mastership of the related data (not that it helps since
938 * we are using c_Next).
939 */
940 while ((bchunk = z->z_RChunks) != NULL) {
941 cpu_ccfence();
942 if (atomic_cmpset_ptr(&z->z_RChunks, bchunk, NULL)) {
943 *z->z_LChunksp = bchunk;
944 while (bchunk) {
945 chunk_mark_free(z, bchunk);
946 z->z_LChunksp = &bchunk->c_Next;
947 bchunk = bchunk->c_Next;
948 ++z->z_NFree;
5fee07e6 949 }
df9daea8 950 break;
5fee07e6 951 }
df9daea8
MD
952 }
953 if (z->z_NFree && nfree == 0) {
954 z->z_Next = slgd->ZoneAry[z->z_ZoneIndex];
955 slgd->ZoneAry[z->z_ZoneIndex] = z;
956 }
5fee07e6 957
df9daea8
MD
958 /*
959 * If the zone becomes totally free, and there are other zones we
960 * can allocate from, move this zone to the FreeZones list. Since
961 * this code can be called from an IPI callback, do *NOT* try to mess
962 * with kernel_map here. Hysteresis will be performed at malloc() time.
963 *
964 * Do not move the zone if there is an IPI inflight, otherwise MP
965 * races can result in our free_remote code accessing a destroyed
966 * zone.
967 */
968 if (z->z_NFree == z->z_NMax &&
969 (z->z_Next || slgd->ZoneAry[z->z_ZoneIndex] != z) &&
970 z->z_RCount == 0
971 ) {
972 SLZone **pz;
973 int *kup;
5fee07e6 974
df9daea8
MD
975 for (pz = &slgd->ZoneAry[z->z_ZoneIndex];
976 z != *pz;
977 pz = &(*pz)->z_Next) {
978 ;
5fee07e6 979 }
df9daea8
MD
980 *pz = z->z_Next;
981 z->z_Magic = -1;
982 z->z_Next = slgd->FreeZones;
983 slgd->FreeZones = z;
984 ++slgd->NFreeZones;
985 kup = btokup(z);
986 *kup = 0;
5fee07e6 987 }
df9daea8 988 logmemory(free_rem_end, z, bchunk, 0, 0);
a108bf71
MD
989}
990
1d712609
MD
991#endif
992
38e34349 993/*
5b287bba 994 * free (SLAB ALLOCATOR)
38e34349
MD
995 *
996 * Free a memory block previously allocated by malloc. Note that we do not
5fee07e6 997 * attempt to update ks_loosememuse as MP races could prevent us from
38e34349 998 * checking memory limits in malloc.
5b287bba
MD
999 *
1000 * MPSAFE
38e34349 1001 */
a108bf71 1002void
8aca2bd4 1003kfree(void *ptr, struct malloc_type *type)
a108bf71
MD
1004{
1005 SLZone *z;
1006 SLChunk *chunk;
1007 SLGlobalData *slgd;
bba6a44d 1008 struct globaldata *gd;
722871d3 1009 int *kup;
5fee07e6 1010 unsigned long size;
d8100bdc
SW
1011#ifdef SMP
1012 SLChunk *bchunk;
5fee07e6 1013 int rsignal;
d8100bdc 1014#endif
a108bf71 1015
b68ad50c 1016 logmemory_quick(free_beg);
bba6a44d
MD
1017 gd = mycpu;
1018 slgd = &gd->gd_slab;
a108bf71 1019
d39911d9
JS
1020 if (ptr == NULL)
1021 panic("trying to free NULL pointer");
1022
a108bf71
MD
1023 /*
1024 * Handle special 0-byte allocations
1025 */
f2b5daf9
MD
1026 if (ptr == ZERO_LENGTH_PTR) {
1027 logmemory(free_zero, ptr, type, -1, 0);
b68ad50c 1028 logmemory_quick(free_end);
a108bf71 1029 return;
f2b5daf9 1030 }
a108bf71 1031
5fee07e6
MD
1032 /*
1033 * Panic on bad malloc type
1034 */
1035 if (type->ks_magic != M_MAGIC)
1036 panic("free: malloc type lacks magic");
1037
a108bf71
MD
1038 /*
1039 * Handle oversized allocations. XXX we really should require that a
1040 * size be passed to free() instead of this nonsense.
bba6a44d
MD
1041 *
1042 * This code is never called via an ipi.
a108bf71 1043 */
5fee07e6 1044 kup = btokup(ptr);
722871d3
MD
1045 if (*kup > 0) {
1046 size = *kup << PAGE_SHIFT;
1047 *kup = 0;
a108bf71 1048#ifdef INVARIANTS
5fee07e6
MD
1049 KKASSERT(sizeof(weirdary) <= size);
1050 bcopy(weirdary, ptr, sizeof(weirdary));
a108bf71 1051#endif
5fee07e6
MD
1052 /*
1053 * NOTE: For oversized allocations we do not record the
1054 * originating cpu. It gets freed on the cpu calling
1055 * kfree(). The statistics are in aggregate.
1056 *
1057 * note: XXX we have still inherited the interrupts-can't-block
1058 * assumption. An interrupt thread does not bump
1059 * gd_intr_nesting_level so check TDF_INTTHREAD. This is
1060 * primarily until we can fix softupdate's assumptions about free().
1061 */
1062 crit_enter();
1063 --type->ks_inuse[gd->gd_cpuid];
1064 type->ks_memuse[gd->gd_cpuid] -= size;
1065 if (mycpu->gd_intr_nesting_level ||
1066 (gd->gd_curthread->td_flags & TDF_INTTHREAD))
1067 {
1068 logmemory(free_ovsz_delayed, ptr, type, size, 0);
1069 z = (SLZone *)ptr;
1070 z->z_Magic = ZALLOC_OVSZ_MAGIC;
1071 z->z_Next = slgd->FreeOvZones;
1072 z->z_ChunkSize = size;
1073 slgd->FreeOvZones = z;
1074 crit_exit();
1075 } else {
1076 crit_exit();
1077 logmemory(free_ovsz, ptr, type, size, 0);
1078 kmem_slab_free(ptr, size); /* may block */
1079 atomic_add_int(&ZoneBigAlloc, -(int)size / 1024);
a108bf71 1080 }
5fee07e6
MD
1081 logmemory_quick(free_end);
1082 return;
a108bf71
MD
1083 }
1084
1085 /*
1086 * Zone case. Figure out the zone based on the fact that it is
1087 * ZoneSize aligned.
1088 */
5fee07e6
MD
1089 z = (SLZone *)((uintptr_t)ptr & ZoneMask);
1090 kup = btokup(z);
722871d3 1091 KKASSERT(*kup < 0);
a108bf71
MD
1092 KKASSERT(z->z_Magic == ZALLOC_SLAB_MAGIC);
1093
1094 /*
5fee07e6
MD
1095 * If we do not own the zone then use atomic ops to free to the
1096 * remote cpu linked list and notify the target zone using a
1097 * passive message.
1098 *
1099 * The target zone cannot be deallocated while we own a chunk of it,
1100 * so the zone header's storage is stable until the very moment
1101 * we adjust z_RChunks. After that we cannot safely dereference (z).
1102 *
1103 * (no critical section needed)
a108bf71 1104 */
2db3b277 1105 if (z->z_CpuGd != gd) {
75c7ffea 1106#ifdef SMP
5fee07e6
MD
1107 /*
1108 * Making these adjustments now allow us to avoid passing (type)
1109 * to the remote cpu. Note that ks_inuse/ks_memuse is being
28135cc2
MD
1110 * adjusted on OUR cpu, not the zone cpu, but it should all still
1111 * sum up properly and cancel out.
5fee07e6 1112 */
28135cc2
MD
1113 crit_enter();
1114 --type->ks_inuse[gd->gd_cpuid];
1115 type->ks_memuse[gd->gd_cpuid] -= z->z_ChunkSize;
1116 crit_exit();
5fee07e6
MD
1117
1118 /*
1119 * WARNING! This code competes with other cpus. Once we
1120 * successfully link the chunk to RChunks the remote
1121 * cpu can rip z's storage out from under us.
df9daea8
MD
1122 *
1123 * Bumping RCount prevents z's storage from getting
1124 * ripped out.
5fee07e6
MD
1125 */
1126 rsignal = z->z_RSignal;
1127 cpu_lfence();
df9daea8
MD
1128 if (rsignal)
1129 atomic_add_int(&z->z_RCount, 1);
5fee07e6
MD
1130
1131 chunk = ptr;
1132 for (;;) {
1133 bchunk = z->z_RChunks;
1134 cpu_ccfence();
1135 chunk->c_Next = bchunk;
1136 cpu_sfence();
1137
1138 if (atomic_cmpset_ptr(&z->z_RChunks, bchunk, chunk))
1139 break;
1140 }
5fee07e6
MD
1141
1142 /*
1143 * We have to signal the remote cpu if our actions will cause
1144 * the remote zone to be placed back on ZoneAry so it can
1145 * move the zone back on.
1146 *
1147 * We only need to deal with NULL->non-NULL RChunk transitions
1148 * and only if z_RSignal is set. We interlock by reading rsignal
1149 * before adding our chunk to RChunks. This should result in
1150 * virtually no IPI traffic.
1151 *
1152 * We can use a passive IPI to reduce overhead even further.
1153 */
1154 if (bchunk == NULL && rsignal) {
1155 logmemory(free_request, ptr, type, z->z_ChunkSize, 0);
1156 lwkt_send_ipiq_passive(z->z_CpuGd, kfree_remote, z);
df9daea8
MD
1157 /* z can get ripped out from under us from this point on */
1158 } else if (rsignal) {
1159 atomic_subtract_int(&z->z_RCount, 1);
1160 /* z can get ripped out from under us from this point on */
5fee07e6 1161 }
75c7ffea
MD
1162#else
1163 panic("Corrupt SLZone");
1164#endif
b68ad50c 1165 logmemory_quick(free_end);
a108bf71
MD
1166 return;
1167 }
1168
5fee07e6
MD
1169 /*
1170 * kfree locally
1171 */
f2b5daf9
MD
1172 logmemory(free_chunk, ptr, type, z->z_ChunkSize, 0);
1173
a108bf71 1174 crit_enter();
a108bf71 1175 chunk = ptr;
10cc6608 1176 chunk_mark_free(z, chunk);
a108bf71
MD
1177
1178 /*
1179 * Put weird data into the memory to detect modifications after freeing,
1180 * illegal pointer use after freeing (we should fault on the odd address),
1181 * and so forth. XXX needs more work, see the old malloc code.
1182 */
1183#ifdef INVARIANTS
1184 if (z->z_ChunkSize < sizeof(weirdary))
1185 bcopy(weirdary, chunk, z->z_ChunkSize);
1186 else
1187 bcopy(weirdary, chunk, sizeof(weirdary));
1188#endif
1189
1190 /*
5fee07e6
MD
1191 * Add this free non-zero'd chunk to a linked list for reuse. Add
1192 * to the front of the linked list so it is more likely to be
1193 * reallocated, since it is already in our L1 cache.
a108bf71 1194 */
6ab8e1da 1195#ifdef INVARIANTS
c439ad8f 1196 if ((vm_offset_t)chunk < KvaStart || (vm_offset_t)chunk >= KvaEnd)
fc92d4aa 1197 panic("BADFREE %p", chunk);
a108bf71 1198#endif
5fee07e6
MD
1199 chunk->c_Next = z->z_LChunks;
1200 z->z_LChunks = chunk;
1201 if (chunk->c_Next == NULL)
1202 z->z_LChunksp = &chunk->c_Next;
1203
6ab8e1da 1204#ifdef INVARIANTS
c439ad8f 1205 if (chunk->c_Next && (vm_offset_t)chunk->c_Next < KvaStart)
a108bf71 1206 panic("BADFREE2");
6ab8e1da 1207#endif
a108bf71
MD
1208
1209 /*
1210 * Bump the number of free chunks. If it becomes non-zero the zone
1211 * must be added back onto the appropriate list.
1212 */
1213 if (z->z_NFree++ == 0) {
1214 z->z_Next = slgd->ZoneAry[z->z_ZoneIndex];
1215 slgd->ZoneAry[z->z_ZoneIndex] = z;
1216 }
1217
bba6a44d
MD
1218 --type->ks_inuse[z->z_Cpu];
1219 type->ks_memuse[z->z_Cpu] -= z->z_ChunkSize;
a108bf71
MD
1220
1221 /*
1222 * If the zone becomes totally free, and there are other zones we
a7cf0021
MD
1223 * can allocate from, move this zone to the FreeZones list. Since
1224 * this code can be called from an IPI callback, do *NOT* try to mess
1225 * with kernel_map here. Hysteresis will be performed at malloc() time.
a108bf71
MD
1226 */
1227 if (z->z_NFree == z->z_NMax &&
df9daea8
MD
1228 (z->z_Next || slgd->ZoneAry[z->z_ZoneIndex] != z) &&
1229 z->z_RCount == 0
a108bf71
MD
1230 ) {
1231 SLZone **pz;
722871d3 1232 int *kup;
a108bf71
MD
1233
1234 for (pz = &slgd->ZoneAry[z->z_ZoneIndex]; z != *pz; pz = &(*pz)->z_Next)
1235 ;
1236 *pz = z->z_Next;
1237 z->z_Magic = -1;
a7cf0021
MD
1238 z->z_Next = slgd->FreeZones;
1239 slgd->FreeZones = z;
1240 ++slgd->NFreeZones;
5fee07e6 1241 kup = btokup(z);
722871d3 1242 *kup = 0;
a108bf71 1243 }
b68ad50c 1244 logmemory_quick(free_end);
a108bf71
MD
1245 crit_exit();
1246}
1247
10cc6608 1248#if defined(INVARIANTS)
5fee07e6 1249
10cc6608
MD
1250/*
1251 * Helper routines for sanity checks
1252 */
1253static
1254void
1255chunk_mark_allocated(SLZone *z, void *chunk)
1256{
1257 int bitdex = ((char *)chunk - (char *)z->z_BasePtr) / z->z_ChunkSize;
1258 __uint32_t *bitptr;
1259
5fee07e6
MD
1260 KKASSERT((((intptr_t)chunk ^ (intptr_t)z) & ZoneMask) == 0);
1261 KASSERT(bitdex >= 0 && bitdex < z->z_NMax,
1262 ("memory chunk %p bit index %d is illegal", chunk, bitdex));
10cc6608
MD
1263 bitptr = &z->z_Bitmap[bitdex >> 5];
1264 bitdex &= 31;
5fee07e6
MD
1265 KASSERT((*bitptr & (1 << bitdex)) == 0,
1266 ("memory chunk %p is already allocated!", chunk));
10cc6608
MD
1267 *bitptr |= 1 << bitdex;
1268}
1269
1270static
1271void
1272chunk_mark_free(SLZone *z, void *chunk)
1273{
1274 int bitdex = ((char *)chunk - (char *)z->z_BasePtr) / z->z_ChunkSize;
1275 __uint32_t *bitptr;
1276
5fee07e6
MD
1277 KKASSERT((((intptr_t)chunk ^ (intptr_t)z) & ZoneMask) == 0);
1278 KASSERT(bitdex >= 0 && bitdex < z->z_NMax,
1279 ("memory chunk %p bit index %d is illegal!", chunk, bitdex));
10cc6608
MD
1280 bitptr = &z->z_Bitmap[bitdex >> 5];
1281 bitdex &= 31;
5fee07e6
MD
1282 KASSERT((*bitptr & (1 << bitdex)) != 0,
1283 ("memory chunk %p is already free!", chunk));
10cc6608
MD
1284 *bitptr &= ~(1 << bitdex);
1285}
1286
1287#endif
1288
a108bf71 1289/*
5b287bba 1290 * kmem_slab_alloc()
a108bf71
MD
1291 *
1292 * Directly allocate and wire kernel memory in PAGE_SIZE chunks with the
1293 * specified alignment. M_* flags are expected in the flags field.
1294 *
1295 * Alignment must be a multiple of PAGE_SIZE.
1296 *
1297 * NOTE! XXX For the moment we use vm_map_entry_reserve/release(),
1298 * but when we move zalloc() over to use this function as its backend
1299 * we will have to switch to kreserve/krelease and call reserve(0)
1300 * after the new space is made available.
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MD
1301 *
1302 * Interrupt code which has preempted other code is not allowed to
c397c465
MD
1303 * use PQ_CACHE pages. However, if an interrupt thread is run
1304 * non-preemptively or blocks and then runs non-preemptively, then
1305 * it is free to use PQ_CACHE pages.
a108bf71
MD
1306 */
1307static void *
1308kmem_slab_alloc(vm_size_t size, vm_offset_t align, int flags)
1309{
1310 vm_size_t i;
1311 vm_offset_t addr;
1de1e800 1312 int count, vmflags, base_vmflags;
bf1a4675 1313 vm_page_t mp[ZALLOC_MAX_ZONE_SIZE / PAGE_SIZE];
dc1fd4b3 1314 thread_t td;
a108bf71
MD
1315
1316 size = round_page(size);
e4846942 1317 addr = vm_map_min(&kernel_map);
a108bf71
MD
1318
1319 /*
5c39c498
MD
1320 * Reserve properly aligned space from kernel_map. RNOWAIT allocations
1321 * cannot block.
a108bf71 1322 */
5c39c498 1323 if (flags & M_RNOWAIT) {
ed2013d8 1324 if (lwkt_trytoken(&vm_token) == 0)
5c39c498
MD
1325 return(NULL);
1326 } else {
ed2013d8 1327 lwkt_gettoken(&vm_token);
5c39c498 1328 }
a108bf71
MD
1329 count = vm_map_entry_reserve(MAP_RESERVE_COUNT);
1330 crit_enter();
e4846942 1331 vm_map_lock(&kernel_map);
c809941b 1332 if (vm_map_findspace(&kernel_map, addr, size, align, 0, &addr)) {
e4846942 1333 vm_map_unlock(&kernel_map);
8cb2bf45 1334 if ((flags & M_NULLOK) == 0)
a108bf71 1335 panic("kmem_slab_alloc(): kernel_map ran out of space!");
a108bf71 1336 vm_map_entry_release(count);
2de4f77e 1337 crit_exit();
ed2013d8 1338 lwkt_reltoken(&vm_token);
a108bf71
MD
1339 return(NULL);
1340 }
e4846942
MD
1341
1342 /*
1343 * kernel_object maps 1:1 to kernel_map.
1344 */
c439ad8f 1345 vm_object_reference(&kernel_object);
e4846942
MD
1346 vm_map_insert(&kernel_map, &count,
1347 &kernel_object, addr, addr, addr + size,
1b874851
MD
1348 VM_MAPTYPE_NORMAL,
1349 VM_PROT_ALL, VM_PROT_ALL,
1350 0);
a108bf71 1351
dc1fd4b3 1352 td = curthread;
dc1fd4b3 1353
1de1e800
JS
1354 base_vmflags = 0;
1355 if (flags & M_ZERO)
1356 base_vmflags |= VM_ALLOC_ZERO;
1357 if (flags & M_USE_RESERVE)
1358 base_vmflags |= VM_ALLOC_SYSTEM;
1359 if (flags & M_USE_INTERRUPT_RESERVE)
1360 base_vmflags |= VM_ALLOC_INTERRUPT;
77912481
MD
1361 if ((flags & (M_RNOWAIT|M_WAITOK)) == 0) {
1362 panic("kmem_slab_alloc: bad flags %08x (%p)",
1363 flags, ((int **)&size)[-1]);
1364 }
1de1e800
JS
1365
1366
a108bf71
MD
1367 /*
1368 * Allocate the pages. Do not mess with the PG_ZERO flag yet.
1369 */
1370 for (i = 0; i < size; i += PAGE_SIZE) {
1371 vm_page_t m;
fe1e98d0
MD
1372
1373 /*
c397c465
MD
1374 * VM_ALLOC_NORMAL can only be set if we are not preempting.
1375 *
1376 * VM_ALLOC_SYSTEM is automatically set if we are preempting and
1377 * M_WAITOK was specified as an alternative (i.e. M_USE_RESERVE is
4ecf7cc9
MD
1378 * implied in this case), though I'm not sure if we really need to
1379 * do that.
fe1e98d0 1380 */
1de1e800 1381 vmflags = base_vmflags;
c397c465 1382 if (flags & M_WAITOK) {
1de1e800 1383 if (td->td_preempted)
fe1e98d0 1384 vmflags |= VM_ALLOC_SYSTEM;
1de1e800 1385 else
dc1fd4b3 1386 vmflags |= VM_ALLOC_NORMAL;
dc1fd4b3 1387 }
a108bf71 1388
e4846942 1389 m = vm_page_alloc(&kernel_object, OFF_TO_IDX(addr + i), vmflags);
c157ff7a 1390 if (i / PAGE_SIZE < NELEM(mp))
bf1a4675 1391 mp[i / PAGE_SIZE] = m;
dc1fd4b3
MD
1392
1393 /*
1394 * If the allocation failed we either return NULL or we retry.
1395 *
c397c465
MD
1396 * If M_WAITOK is specified we wait for more memory and retry.
1397 * If M_WAITOK is specified from a preemption we yield instead of
1398 * wait. Livelock will not occur because the interrupt thread
1399 * will not be preempting anyone the second time around after the
1400 * yield.
dc1fd4b3 1401 */
a108bf71 1402 if (m == NULL) {
c397c465 1403 if (flags & M_WAITOK) {
fe1e98d0 1404 if (td->td_preempted) {
e4846942 1405 vm_map_unlock(&kernel_map);
77912481 1406 lwkt_switch();
e4846942 1407 vm_map_lock(&kernel_map);
dc1fd4b3 1408 } else {
e4846942 1409 vm_map_unlock(&kernel_map);
4ecf7cc9 1410 vm_wait(0);
e4846942 1411 vm_map_lock(&kernel_map);
dc1fd4b3 1412 }
a108bf71
MD
1413 i -= PAGE_SIZE; /* retry */
1414 continue;
1415 }
dc1fd4b3
MD
1416
1417 /*
1418 * We were unable to recover, cleanup and return NULL
2de4f77e
MD
1419 *
1420 * (vm_token already held)
dc1fd4b3 1421 */
a108bf71
MD
1422 while (i != 0) {
1423 i -= PAGE_SIZE;
e4846942 1424 m = vm_page_lookup(&kernel_object, OFF_TO_IDX(addr + i));
17cde63e 1425 /* page should already be busy */
a108bf71
MD
1426 vm_page_free(m);
1427 }
e4846942
MD
1428 vm_map_delete(&kernel_map, addr, addr + size, &count);
1429 vm_map_unlock(&kernel_map);
a108bf71 1430 vm_map_entry_release(count);
2de4f77e 1431 crit_exit();
ed2013d8 1432 lwkt_reltoken(&vm_token);
a108bf71
MD
1433 return(NULL);
1434 }
1435 }
1436
1437 /*
dc1fd4b3
MD
1438 * Success!
1439 *
a108bf71
MD
1440 * Mark the map entry as non-pageable using a routine that allows us to
1441 * populate the underlying pages.
17cde63e
MD
1442 *
1443 * The pages were busied by the allocations above.
a108bf71 1444 */
e4846942 1445 vm_map_set_wired_quick(&kernel_map, addr, size, &count);
a108bf71
MD
1446 crit_exit();
1447
1448 /*
1449 * Enter the pages into the pmap and deal with PG_ZERO and M_ZERO.
1450 */
1451 for (i = 0; i < size; i += PAGE_SIZE) {
1452 vm_page_t m;
1453
c157ff7a 1454 if (i / PAGE_SIZE < NELEM(mp))
bf1a4675
VS
1455 m = mp[i / PAGE_SIZE];
1456 else
1457 m = vm_page_lookup(&kernel_object, OFF_TO_IDX(addr + i));
a108bf71 1458 m->valid = VM_PAGE_BITS_ALL;
17cde63e 1459 /* page should already be busy */
a108bf71 1460 vm_page_wire(m);
fbbaeba3 1461 pmap_enter(&kernel_pmap, addr + i, m, VM_PROT_ALL, 1);
a108bf71
MD
1462 if ((m->flags & PG_ZERO) == 0 && (flags & M_ZERO))
1463 bzero((char *)addr + i, PAGE_SIZE);
1464 vm_page_flag_clear(m, PG_ZERO);
17cde63e
MD
1465 KKASSERT(m->flags & (PG_WRITEABLE | PG_MAPPED));
1466 vm_page_flag_set(m, PG_REFERENCED);
a491077e 1467 vm_page_wakeup(m);
a108bf71 1468 }
e4846942 1469 vm_map_unlock(&kernel_map);
a108bf71 1470 vm_map_entry_release(count);
ed2013d8 1471 lwkt_reltoken(&vm_token);
a108bf71
MD
1472 return((void *)addr);
1473}
1474
38e34349 1475/*
5b287bba 1476 * kmem_slab_free()
38e34349 1477 */
a108bf71
MD
1478static void
1479kmem_slab_free(void *ptr, vm_size_t size)
1480{
1481 crit_enter();
ed2013d8 1482 lwkt_gettoken(&vm_token);
e4846942 1483 vm_map_remove(&kernel_map, (vm_offset_t)ptr, (vm_offset_t)ptr + size);
ed2013d8 1484 lwkt_reltoken(&vm_token);
a108bf71
MD
1485 crit_exit();
1486}
1487