1/*
2 * Copyright (c) 2006-2019 Apple Inc. All rights reserved.
3 *
4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5 *
6 * This file contains Original Code and/or Modifications of Original Code
7 * as defined in and that are subject to the Apple Public Source License
8 * Version 2.0 (the 'License'). You may not use this file except in
9 * compliance with the License. The rights granted to you under the License
10 * may not be used to create, or enable the creation or redistribution of,
11 * unlawful or unlicensed copies of an Apple operating system, or to
12 * circumvent, violate, or enable the circumvention or violation of, any
13 * terms of an Apple operating system software license agreement.
14 *
15 * Please obtain a copy of the License at
16 * http://www.opensource.apple.com/apsl/ and read it before using this file.
17 *
18 * The Original Code and all software distributed under the License are
19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23 * Please see the License for the specific language governing rights and
24 * limitations under the License.
25 *
26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27 */
28#ifndef _SYS_MCACHE_H
29#define _SYS_MCACHE_H
30
31#ifdef KERNEL_PRIVATE
32
33#ifdef __cplusplus
34extern "C" {
35#endif
36
37#include <sys/types.h>
38#include <sys/queue.h>
39#include <mach/boolean.h>
40#include <kern/locks.h>
41#include <libkern/OSAtomic.h>
42
43#ifdef ASSERT
44#undef ASSERT
45#endif
46
47#ifdef VERIFY
48#undef VERIFY
49#endif
50
51/*
52 * Unlike VERIFY(), ASSERT() is evaluated only in DEBUG/DEVELOPMENT build.
53 */
54#define VERIFY(EX) \
55 ((void)(__probable((EX)) || assfail(#EX, __FILE__, __LINE__)))
56#if (DEBUG || DEVELOPMENT)
57#define ASSERT(EX) VERIFY(EX)
58#else
59#define ASSERT(EX) ((void)0)
60#endif
61
62/*
63 * Compile time assert; this should be on its own someday.
64 */
65#define _CASSERT(x) _Static_assert(x, "compile-time assertion failed")
66
67/*
68 * Use CPU_CACHE_LINE_SIZE instead of MAX_CPU_CACHE_LINE_SIZE, unless
69 * wasting space is of no concern.
70 */
71#define MAX_CPU_CACHE_LINE_SIZE 128
72#define CPU_CACHE_LINE_SIZE mcache_cache_line_size()
73
74#ifndef IS_P2ALIGNED
75#define IS_P2ALIGNED(v, a) \
76 ((((uintptr_t)(v)) & ((uintptr_t)(a) - 1)) == 0)
77#endif /* IS_P2ALIGNED */
78
79#ifndef P2ROUNDUP
80#define P2ROUNDUP(x, align) \
81 (-(-((uintptr_t)(x)) & -((uintptr_t)align)))
82#endif /* P2ROUNDUP */
83
84#ifndef P2ROUNDDOWN
85#define P2ROUNDDOWN(x, align) \
86 (((uintptr_t)(x)) & ~((uintptr_t)(align) - 1))
87#endif /* P2ROUNDDOWN */
88
89#ifndef P2ALIGN
90#define P2ALIGN(x, align) \
91 ((uintptr_t)(x) & -((uintptr_t)(align)))
92#endif /* P2ALIGN */
93
94#define MCACHE_FREE_PATTERN 0xdeadbeefdeadbeefULL
95#define MCACHE_UNINITIALIZED_PATTERN 0xbaddcafebaddcafeULL
96
97/*
98 * mcache allocation request flags.
99 *
100 * MCR_NOSLEEP and MCR_FAILOK are mutually exclusive. The latter is used
101 * by the mbuf allocator to handle the implementation of several caches that
102 * involve multiple layers of mcache. It implies a best effort blocking
103 * allocation request; if the request cannot be satisfied, the caller will
104 * be blocked until further notice, similar to MCR_SLEEP, except that upon
105 * a wake up it will return immediately to the caller regardless of whether
106 * the request can been fulfilled.
107 *
108 * MCR_TRYHARD implies a non-blocking allocation request, regardless of
109 * whether MCR_NOSLEEP is set. It informs the allocator that the request
110 * should not cause the calling thread to block, and that it must have
111 * exhausted all possible schemes to fulfill the request, including doing
112 * reclaims and/or purges, before returning to the caller.
113 *
114 * Regular mcache clients should only use MCR_SLEEP or MCR_NOSLEEP.
115 */
116#define MCR_SLEEP 0x0000 /* same as M_WAITOK */
117#define MCR_NOSLEEP 0x0001 /* same as M_NOWAIT */
118#define MCR_FAILOK 0x0100 /* private, for internal use only */
119#define MCR_TRYHARD 0x0200 /* private, for internal use only */
120#define MCR_USR1 0x1000 /* private, for internal use only */
121
122#define MCR_NONBLOCKING (MCR_NOSLEEP | MCR_FAILOK | MCR_TRYHARD)
123
124/*
125 * Generic one-way linked list element structure. This is used to handle
126 * mcache_alloc_ext() requests in order to chain the allocated objects
127 * together before returning them to the caller.
128 */
129typedef struct mcache_obj {
130 struct mcache_obj *obj_next;
131} mcache_obj_t;
132
133typedef struct mcache_bkt {
134 void *bkt_next; /* next bucket in list */
135 struct mcache_bkttype *bkt_type; /* bucket type */
136 void *bkt_obj[1]; /* one or more objects */
137} mcache_bkt_t;
138
139typedef struct mcache_bktlist {
140 mcache_bkt_t *bl_list; /* bucket list */
141 u_int32_t bl_total; /* number of buckets */
142 u_int32_t bl_min; /* min since last update */
143 u_int32_t bl_reaplimit; /* max reapable buckets */
144 u_int64_t bl_alloc; /* allocations from this list */
145} mcache_bktlist_t;
146
147typedef struct mcache_bkttype {
148 int bt_bktsize; /* bucket size (number of elements) */
149 size_t bt_minbuf; /* all smaller buffers qualify */
150 size_t bt_maxbuf; /* no larger bfufers qualify */
151 struct mcache *bt_cache; /* bucket cache */
152} mcache_bkttype_t;
153
154typedef struct mcache_cpu {
155 decl_lck_mtx_data(, cc_lock);
156 mcache_bkt_t *cc_filled; /* the currently filled bucket */
157 mcache_bkt_t *cc_pfilled; /* the previously filled bucket */
158 u_int64_t cc_alloc; /* allocations from this cpu */
159 u_int64_t cc_free; /* frees to this cpu */
160 int cc_objs; /* number of objects in filled bkt */
161 int cc_pobjs; /* number of objects in previous bkt */
162 int cc_bktsize; /* number of elements in a full bkt */
163} __attribute__((aligned(MAX_CPU_CACHE_LINE_SIZE))) mcache_cpu_t;
164
165typedef unsigned int (*mcache_allocfn_t)(void *, mcache_obj_t ***,
166 unsigned int, int);
167typedef void (*mcache_freefn_t)(void *, mcache_obj_t *, boolean_t);
168typedef void (*mcache_auditfn_t)(void *, mcache_obj_t *, boolean_t);
169typedef void (*mcache_logfn_t)(u_int32_t, mcache_obj_t *, boolean_t);
170typedef void (*mcache_notifyfn_t)(void *, u_int32_t);
171
172typedef struct mcache {
173 /*
174 * Cache properties
175 */
176 LIST_ENTRY(mcache) mc_list; /* cache linkage */
177 char mc_name[32]; /* cache name */
178 struct zone *mc_slab_zone; /* backend zone allocator */
179 mcache_allocfn_t mc_slab_alloc; /* slab layer allocate callback */
180 mcache_freefn_t mc_slab_free; /* slab layer free callback */
181 mcache_auditfn_t mc_slab_audit; /* slab layer audit callback */
182 mcache_logfn_t mc_slab_log; /* slab layer log callback */
183 mcache_notifyfn_t mc_slab_notify; /* slab layer notify callback */
184 void *mc_private; /* opaque arg to callbacks */
185 size_t mc_bufsize; /* object size */
186 size_t mc_align; /* object alignment */
187 u_int32_t mc_flags; /* cache creation flags */
188 u_int32_t mc_purge_cnt; /* # of purges requested by slab */
189 u_int32_t mc_enable_cnt; /* # of reenables due to purges */
190 u_int32_t mc_waiter_cnt; /* # of slab layer waiters */
191 u_int32_t mc_wretry_cnt; /* # of wait retries */
192 u_int32_t mc_nwretry_cnt; /* # of no-wait retry attempts */
193 u_int32_t mc_nwfail_cnt; /* # of no-wait retries that failed */
194 decl_lck_mtx_data(, mc_sync_lock); /* protects purges and reenables */
195 lck_grp_t *mc_sync_lock_grp;
196 /*
197 * Keep CPU and buckets layers lock statistics separate.
198 */
199 lck_grp_t *mc_cpu_lock_grp;
200
201 /*
202 * Bucket layer common to all CPUs
203 */
204 decl_lck_mtx_data(, mc_bkt_lock);
205 lck_grp_t *mc_bkt_lock_grp;
206 mcache_bkttype_t *cache_bkttype; /* bucket type */
207 mcache_bktlist_t mc_full; /* full buckets */
208 mcache_bktlist_t mc_empty; /* empty buckets */
209 size_t mc_chunksize; /* bufsize + alignment */
210 u_int32_t mc_bkt_contention; /* lock contention count */
211 u_int32_t mc_bkt_contention_prev; /* previous snapshot */
212
213 /*
214 * Per-CPU layer, aligned at cache line boundary
215 */
216 mcache_cpu_t mc_cpu[1]
217 __attribute__((aligned(MAX_CPU_CACHE_LINE_SIZE)));
218} mcache_t;
219
220#define MCACHE_ALIGN 8 /* default guaranteed alignment */
221
222/* Valid values for mc_flags */
223#define MCF_VERIFY 0x00000001 /* enable verification */
224#define MCF_TRACE 0x00000002 /* enable transaction auditing */
225#define MCF_NOCPUCACHE 0x00000010 /* disable CPU layer caching */
226#define MCF_NOLEAKLOG 0x00000100 /* disable leak logging */
227#define MCF_EXPLEAKLOG 0x00000200 /* expose leak info to user space */
228
229#define MCF_DEBUG (MCF_VERIFY | MCF_TRACE)
230#define MCF_FLAGS_MASK \
231 (MCF_DEBUG | MCF_NOCPUCACHE | MCF_NOLEAKLOG | MCF_EXPLEAKLOG)
232
233/* Valid values for notify callback */
234#define MCN_RETRYALLOC 0x00000001 /* Allocation should be retried */
235
236#define MCACHE_STACK_DEPTH 16
237
238#define MCA_TRN_MAX 2 /* Number of transactions to record */
239
240#define DUMP_MCA_BUF_SIZE 512
241
242typedef struct mcache_audit {
243 struct mcache_audit *mca_next; /* next audit struct */
244 void *mca_addr; /* address of buffer */
245 mcache_t *mca_cache; /* parent cache of the buffer */
246 size_t mca_contents_size; /* size of saved contents */
247 void *mca_contents; /* user-specific saved contents */
248 void *mca_uptr; /* user-specific pointer */
249 uint32_t mca_uflags; /* user-specific flags */
250 uint32_t mca_next_trn;
251 struct mca_trn {
252 struct thread *mca_thread; /* thread doing transaction */
253 uint32_t mca_tstamp;
254 uint16_t mca_depth;
255 void *mca_stack[MCACHE_STACK_DEPTH];
256 } mca_trns[MCA_TRN_MAX];
257} mcache_audit_t;
258
259__private_extern__ int assfail(const char *, const char *, int) __abortlike;
260__private_extern__ void mcache_init(void);
261__private_extern__ unsigned int mcache_getflags(void);
262__private_extern__ unsigned int mcache_cache_line_size(void);
263__private_extern__ mcache_t *mcache_create(const char *, size_t,
264 size_t, u_int32_t, int);
265__private_extern__ void *mcache_alloc(mcache_t *, int);
266__private_extern__ void mcache_free(mcache_t *, void *);
267__private_extern__ mcache_t *mcache_create_ext(const char *, size_t,
268 mcache_allocfn_t, mcache_freefn_t, mcache_auditfn_t, mcache_logfn_t,
269 mcache_notifyfn_t, void *__unsafe_indexable, u_int32_t, int);
270__private_extern__ void mcache_destroy(mcache_t *);
271__private_extern__ unsigned int mcache_alloc_ext(mcache_t *, mcache_obj_t **,
272 unsigned int, int);
273__private_extern__ void mcache_free_ext(mcache_t *, mcache_obj_t *);
274__private_extern__ void mcache_reap(void);
275__private_extern__ void mcache_reap_now(mcache_t *, boolean_t);
276__private_extern__ boolean_t mcache_purge_cache(mcache_t *, boolean_t);
277__private_extern__ void mcache_waiter_inc(mcache_t *);
278__private_extern__ void mcache_waiter_dec(mcache_t *);
279__private_extern__ boolean_t mcache_bkt_isempty(mcache_t *);
280
281struct timeval;
282__private_extern__ void mcache_buffer_log(mcache_audit_t *, void *, mcache_t *,
283 struct timeval *);
284__private_extern__ void mcache_set_pattern(u_int64_t, void *, size_t);
285__private_extern__ void *mcache_verify_pattern(u_int64_t, void *, size_t);
286__private_extern__ void mcache_audit_free_verify(mcache_audit_t *,
287 void *, size_t, size_t);
288__private_extern__ void mcache_audit_free_verify_set(mcache_audit_t *,
289 void *, size_t, size_t);
290__private_extern__ char *mcache_dump_mca(char buf[DUMP_MCA_BUF_SIZE], mcache_audit_t *);
291
292extern mcache_t *mcache_audit_cache;
293
294#ifdef __cplusplus
295}
296#endif
297
298#endif /* KERNEL_PRIVATE */
299
300#endif /* _SYS_MCACHE_H */
301