Willy Tarreau | c7e4238 | 2012-08-24 19:22:53 +0200 | [diff] [blame] | 1 | /* |
| 2 | * include/common/buffer.h |
| 3 | * Buffer management definitions, macros and inline functions. |
| 4 | * |
| 5 | * Copyright (C) 2000-2012 Willy Tarreau - w@1wt.eu |
| 6 | * |
| 7 | * This library is free software; you can redistribute it and/or |
| 8 | * modify it under the terms of the GNU Lesser General Public |
| 9 | * License as published by the Free Software Foundation, version 2.1 |
| 10 | * exclusively. |
| 11 | * |
| 12 | * This library is distributed in the hope that it will be useful, |
| 13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 15 | * Lesser General Public License for more details. |
| 16 | * |
| 17 | * You should have received a copy of the GNU Lesser General Public |
| 18 | * License along with this library; if not, write to the Free Software |
| 19 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 20 | */ |
| 21 | |
| 22 | #ifndef _COMMON_BUFFER_H |
| 23 | #define _COMMON_BUFFER_H |
| 24 | |
| 25 | #include <stdio.h> |
| 26 | #include <stdlib.h> |
| 27 | #include <string.h> |
| 28 | |
Willy Tarreau | 41806d1 | 2018-07-11 09:39:05 +0200 | [diff] [blame] | 29 | #include <common/buf.h> |
Willy Tarreau | 8c89c20 | 2012-09-28 16:02:48 +0200 | [diff] [blame] | 30 | #include <common/chunk.h> |
Willy Tarreau | c7e4238 | 2012-08-24 19:22:53 +0200 | [diff] [blame] | 31 | #include <common/config.h> |
Willy Tarreau | 6634b63 | 2017-09-22 15:02:54 +0200 | [diff] [blame] | 32 | #include <common/ist.h> |
Willy Tarreau | ea1b06d | 2018-07-12 09:02:47 +0200 | [diff] [blame] | 33 | #include <common/istbuf.h> |
Willy Tarreau | 9b28e03 | 2012-10-12 23:49:43 +0200 | [diff] [blame] | 34 | #include <common/memory.h> |
Willy Tarreau | c7e4238 | 2012-08-24 19:22:53 +0200 | [diff] [blame] | 35 | |
| 36 | |
Christopher Faulet | a73e59b | 2016-12-09 17:30:18 +0100 | [diff] [blame] | 37 | /* an element of the <buffer_wq> list. It represents an object that need to |
| 38 | * acquire a buffer to continue its process. */ |
| 39 | struct buffer_wait { |
| 40 | void *target; /* The waiting object that should be woken up */ |
| 41 | int (*wakeup_cb)(void *); /* The function used to wake up the <target>, passed as argument */ |
| 42 | struct list list; /* Next element in the <buffer_wq> list */ |
| 43 | }; |
| 44 | |
Willy Tarreau | bafbe01 | 2017-11-24 17:34:44 +0100 | [diff] [blame] | 45 | extern struct pool_head *pool_head_buffer; |
Willy Tarreau | 2a4b543 | 2014-11-24 11:39:34 +0100 | [diff] [blame] | 46 | extern struct buffer buf_empty; |
Willy Tarreau | f2f7d6b | 2014-11-24 11:55:08 +0100 | [diff] [blame] | 47 | extern struct buffer buf_wanted; |
Christopher Faulet | a73e59b | 2016-12-09 17:30:18 +0100 | [diff] [blame] | 48 | extern struct list buffer_wq; |
Willy Tarreau | 53bae85 | 2017-11-26 11:00:37 +0100 | [diff] [blame] | 49 | __decl_hathreads(extern HA_SPINLOCK_T buffer_wq_lock); |
Willy Tarreau | c7e4238 | 2012-08-24 19:22:53 +0200 | [diff] [blame] | 50 | |
Willy Tarreau | 9b28e03 | 2012-10-12 23:49:43 +0200 | [diff] [blame] | 51 | int init_buffer(); |
Christopher Faulet | ad405f1 | 2017-08-29 15:30:11 +0200 | [diff] [blame] | 52 | void deinit_buffer(); |
Willy Tarreau | af81935 | 2012-08-27 22:08:00 +0200 | [diff] [blame] | 53 | int buffer_replace2(struct buffer *b, char *pos, char *end, const char *str, int len); |
| 54 | int buffer_insert_line2(struct buffer *b, char *pos, const char *str, int len); |
Willy Tarreau | c7e4238 | 2012-08-24 19:22:53 +0200 | [diff] [blame] | 55 | void buffer_dump(FILE *o, struct buffer *b, int from, int to); |
Willy Tarreau | c7e4238 | 2012-08-24 19:22:53 +0200 | [diff] [blame] | 56 | |
| 57 | /*****************************************************************/ |
| 58 | /* These functions are used to compute various buffer area sizes */ |
| 59 | /*****************************************************************/ |
| 60 | |
Willy Tarreau | c7e4238 | 2012-08-24 19:22:53 +0200 | [diff] [blame] | 61 | |
Willy Tarreau | eac5259 | 2018-06-15 13:59:36 +0200 | [diff] [blame] | 62 | |
| 63 | /***** FIXME: OLD API BELOW *****/ |
Willy Tarreau | c7e4238 | 2012-08-24 19:22:53 +0200 | [diff] [blame] | 64 | |
Willy Tarreau | c7e4238 | 2012-08-24 19:22:53 +0200 | [diff] [blame] | 65 | /* Normalizes a pointer after an addition */ |
| 66 | static inline char *buffer_wrap_add(const struct buffer *buf, char *ptr) |
| 67 | { |
Willy Tarreau | 591d445 | 2018-06-15 17:21:00 +0200 | [diff] [blame] | 68 | if (ptr - buf->size >= b_orig(buf)) |
Willy Tarreau | c7e4238 | 2012-08-24 19:22:53 +0200 | [diff] [blame] | 69 | ptr -= buf->size; |
| 70 | return ptr; |
| 71 | } |
| 72 | |
Willy Tarreau | c7e4238 | 2012-08-24 19:22:53 +0200 | [diff] [blame] | 73 | /* Normalizes a pointer which is supposed to be relative to the beginning of a |
| 74 | * buffer, so that wrapping is correctly handled. The intent is to use this |
| 75 | * when increasing a pointer. Note that the wrapping test is only performed |
| 76 | * once, so the original pointer must be between ->data-size and ->data+2*size-1, |
| 77 | * otherwise an invalid pointer might be returned. |
| 78 | */ |
| 79 | static inline const char *buffer_pointer(const struct buffer *buf, const char *ptr) |
| 80 | { |
Willy Tarreau | 591d445 | 2018-06-15 17:21:00 +0200 | [diff] [blame] | 81 | if (ptr < b_orig(buf)) |
Willy Tarreau | c7e4238 | 2012-08-24 19:22:53 +0200 | [diff] [blame] | 82 | ptr += buf->size; |
Willy Tarreau | 591d445 | 2018-06-15 17:21:00 +0200 | [diff] [blame] | 83 | else if (ptr - buf->size >= b_orig(buf)) |
Willy Tarreau | c7e4238 | 2012-08-24 19:22:53 +0200 | [diff] [blame] | 84 | ptr -= buf->size; |
| 85 | return ptr; |
| 86 | } |
| 87 | |
| 88 | /* Returns the distance between two pointers, taking into account the ability |
| 89 | * to wrap around the buffer's end. |
| 90 | */ |
| 91 | static inline int buffer_count(const struct buffer *buf, const char *from, const char *to) |
| 92 | { |
| 93 | int count = to - from; |
Willy Tarreau | bf43927 | 2013-04-02 01:25:57 +0200 | [diff] [blame] | 94 | |
| 95 | count += count < 0 ? buf->size : 0; |
Willy Tarreau | c7e4238 | 2012-08-24 19:22:53 +0200 | [diff] [blame] | 96 | return count; |
| 97 | } |
| 98 | |
Willy Tarreau | c7e4238 | 2012-08-24 19:22:53 +0200 | [diff] [blame] | 99 | /* Return 1 if the buffer has less than 1/4 of its capacity free, otherwise 0 */ |
| 100 | static inline int buffer_almost_full(const struct buffer *buf) |
| 101 | { |
Willy Tarreau | 4428a29 | 2014-11-28 20:54:13 +0100 | [diff] [blame] | 102 | if (buf == &buf_empty) |
| 103 | return 0; |
| 104 | |
Willy Tarreau | bbc68df | 2018-06-06 14:30:50 +0200 | [diff] [blame] | 105 | return b_almost_full(buf); |
Willy Tarreau | c7e4238 | 2012-08-24 19:22:53 +0200 | [diff] [blame] | 106 | } |
| 107 | |
Willy Tarreau | af81935 | 2012-08-27 22:08:00 +0200 | [diff] [blame] | 108 | /* This function writes the string <str> at position <pos> which must be in |
| 109 | * buffer <b>, and moves <end> just after the end of <str>. <b>'s parameters |
| 110 | * (l, r, lr) are updated to be valid after the shift. the shift value |
| 111 | * (positive or negative) is returned. If there's no space left, the move is |
| 112 | * not done. The function does not adjust ->o because it does not make sense |
| 113 | * to use it on data scheduled to be sent. |
| 114 | */ |
| 115 | static inline int buffer_replace(struct buffer *b, char *pos, char *end, const char *str) |
| 116 | { |
| 117 | return buffer_replace2(b, pos, end, str, strlen(str)); |
| 118 | } |
| 119 | |
Willy Tarreau | f2f7d6b | 2014-11-24 11:55:08 +0100 | [diff] [blame] | 120 | /* Allocates a buffer and replaces *buf with this buffer. If no memory is |
| 121 | * available, &buf_wanted is used instead. No control is made to check if *buf |
| 122 | * already pointed to another buffer. The allocated buffer is returned, or |
| 123 | * NULL in case no memory is available. |
Willy Tarreau | e583ea5 | 2014-11-24 11:30:16 +0100 | [diff] [blame] | 124 | */ |
| 125 | static inline struct buffer *b_alloc(struct buffer **buf) |
| 126 | { |
Willy Tarreau | f2f7d6b | 2014-11-24 11:55:08 +0100 | [diff] [blame] | 127 | struct buffer *b; |
| 128 | |
| 129 | *buf = &buf_wanted; |
Willy Tarreau | bafbe01 | 2017-11-24 17:34:44 +0100 | [diff] [blame] | 130 | b = pool_alloc_dirty(pool_head_buffer); |
Willy Tarreau | f2f7d6b | 2014-11-24 11:55:08 +0100 | [diff] [blame] | 131 | if (likely(b)) { |
Willy Tarreau | bafbe01 | 2017-11-24 17:34:44 +0100 | [diff] [blame] | 132 | b->size = pool_head_buffer->size - sizeof(struct buffer); |
Willy Tarreau | f2f7d6b | 2014-11-24 11:55:08 +0100 | [diff] [blame] | 133 | b_reset(b); |
| 134 | *buf = b; |
Willy Tarreau | e583ea5 | 2014-11-24 11:30:16 +0100 | [diff] [blame] | 135 | } |
Willy Tarreau | f2f7d6b | 2014-11-24 11:55:08 +0100 | [diff] [blame] | 136 | return b; |
Willy Tarreau | e583ea5 | 2014-11-24 11:30:16 +0100 | [diff] [blame] | 137 | } |
| 138 | |
Willy Tarreau | 620bd6c | 2014-12-08 16:37:26 +0100 | [diff] [blame] | 139 | /* Allocates a buffer and replaces *buf with this buffer. If no memory is |
| 140 | * available, &buf_wanted is used instead. No control is made to check if *buf |
| 141 | * already pointed to another buffer. The allocated buffer is returned, or |
| 142 | * NULL in case no memory is available. The difference with b_alloc() is that |
| 143 | * this function only picks from the pool and never calls malloc(), so it can |
| 144 | * fail even if some memory is available. |
| 145 | */ |
| 146 | static inline struct buffer *b_alloc_fast(struct buffer **buf) |
| 147 | { |
| 148 | struct buffer *b; |
| 149 | |
| 150 | *buf = &buf_wanted; |
Willy Tarreau | bafbe01 | 2017-11-24 17:34:44 +0100 | [diff] [blame] | 151 | b = pool_get_first(pool_head_buffer); |
Willy Tarreau | 620bd6c | 2014-12-08 16:37:26 +0100 | [diff] [blame] | 152 | if (likely(b)) { |
Willy Tarreau | bafbe01 | 2017-11-24 17:34:44 +0100 | [diff] [blame] | 153 | b->size = pool_head_buffer->size - sizeof(struct buffer); |
Willy Tarreau | 620bd6c | 2014-12-08 16:37:26 +0100 | [diff] [blame] | 154 | b_reset(b); |
| 155 | *buf = b; |
| 156 | } |
| 157 | return b; |
| 158 | } |
| 159 | |
Willy Tarreau | 2a4b543 | 2014-11-24 11:39:34 +0100 | [diff] [blame] | 160 | /* Releases buffer *buf (no check of emptiness) */ |
| 161 | static inline void __b_drop(struct buffer **buf) |
Willy Tarreau | 7dfca9d | 2014-11-25 19:45:11 +0100 | [diff] [blame] | 162 | { |
Willy Tarreau | bafbe01 | 2017-11-24 17:34:44 +0100 | [diff] [blame] | 163 | pool_free(pool_head_buffer, *buf); |
Willy Tarreau | 7dfca9d | 2014-11-25 19:45:11 +0100 | [diff] [blame] | 164 | } |
| 165 | |
Willy Tarreau | 2a4b543 | 2014-11-24 11:39:34 +0100 | [diff] [blame] | 166 | /* Releases buffer *buf if allocated. */ |
| 167 | static inline void b_drop(struct buffer **buf) |
| 168 | { |
| 169 | if (!(*buf)->size) |
| 170 | return; |
| 171 | __b_drop(buf); |
| 172 | } |
| 173 | |
| 174 | /* Releases buffer *buf if allocated, and replaces it with &buf_empty. */ |
| 175 | static inline void b_free(struct buffer **buf) |
| 176 | { |
| 177 | b_drop(buf); |
| 178 | *buf = &buf_empty; |
| 179 | } |
| 180 | |
Willy Tarreau | f4718e8 | 2014-12-02 13:54:01 +0100 | [diff] [blame] | 181 | /* Ensures that <buf> is allocated. If an allocation is needed, it ensures that |
| 182 | * there are still at least <margin> buffers available in the pool after this |
| 183 | * allocation so that we don't leave the pool in a condition where a session or |
| 184 | * a response buffer could not be allocated anymore, resulting in a deadlock. |
| 185 | * This means that we sometimes need to try to allocate extra entries even if |
| 186 | * only one buffer is needed. |
Christopher Faulet | fa5c812 | 2017-11-10 10:39:16 +0100 | [diff] [blame] | 187 | * |
| 188 | * We need to lock the pool here to be sure to have <margin> buffers available |
| 189 | * after the allocation, regardless how many threads that doing it in the same |
| 190 | * time. So, we use internal and lockless memory functions (prefixed with '__'). |
Willy Tarreau | f4718e8 | 2014-12-02 13:54:01 +0100 | [diff] [blame] | 191 | */ |
| 192 | static inline struct buffer *b_alloc_margin(struct buffer **buf, int margin) |
| 193 | { |
Christopher Faulet | fa5c812 | 2017-11-10 10:39:16 +0100 | [diff] [blame] | 194 | struct buffer *b; |
Willy Tarreau | f4718e8 | 2014-12-02 13:54:01 +0100 | [diff] [blame] | 195 | |
| 196 | if ((*buf)->size) |
| 197 | return *buf; |
| 198 | |
Christopher Faulet | fa5c812 | 2017-11-10 10:39:16 +0100 | [diff] [blame] | 199 | *buf = &buf_wanted; |
Willy Tarreau | f161d0f | 2018-02-22 14:05:55 +0100 | [diff] [blame] | 200 | #ifndef CONFIG_HAP_LOCKLESS_POOLS |
Willy Tarreau | bafbe01 | 2017-11-24 17:34:44 +0100 | [diff] [blame] | 201 | HA_SPIN_LOCK(POOL_LOCK, &pool_head_buffer->lock); |
Olivier Houchard | cf975d4 | 2018-01-24 18:38:31 +0100 | [diff] [blame] | 202 | #endif |
Christopher Faulet | fa5c812 | 2017-11-10 10:39:16 +0100 | [diff] [blame] | 203 | |
Willy Tarreau | f4718e8 | 2014-12-02 13:54:01 +0100 | [diff] [blame] | 204 | /* fast path */ |
Willy Tarreau | bafbe01 | 2017-11-24 17:34:44 +0100 | [diff] [blame] | 205 | if ((pool_head_buffer->allocated - pool_head_buffer->used) > margin) { |
| 206 | b = __pool_get_first(pool_head_buffer); |
Christopher Faulet | fa5c812 | 2017-11-10 10:39:16 +0100 | [diff] [blame] | 207 | if (likely(b)) { |
Willy Tarreau | f161d0f | 2018-02-22 14:05:55 +0100 | [diff] [blame] | 208 | #ifndef CONFIG_HAP_LOCKLESS_POOLS |
Willy Tarreau | bafbe01 | 2017-11-24 17:34:44 +0100 | [diff] [blame] | 209 | HA_SPIN_UNLOCK(POOL_LOCK, &pool_head_buffer->lock); |
Olivier Houchard | cf975d4 | 2018-01-24 18:38:31 +0100 | [diff] [blame] | 210 | #endif |
Willy Tarreau | bafbe01 | 2017-11-24 17:34:44 +0100 | [diff] [blame] | 211 | b->size = pool_head_buffer->size - sizeof(struct buffer); |
Christopher Faulet | fa5c812 | 2017-11-10 10:39:16 +0100 | [diff] [blame] | 212 | b_reset(b); |
| 213 | *buf = b; |
| 214 | return b; |
| 215 | } |
| 216 | } |
Willy Tarreau | f4718e8 | 2014-12-02 13:54:01 +0100 | [diff] [blame] | 217 | |
Christopher Faulet | fa5c812 | 2017-11-10 10:39:16 +0100 | [diff] [blame] | 218 | /* slow path, uses malloc() */ |
Willy Tarreau | bafbe01 | 2017-11-24 17:34:44 +0100 | [diff] [blame] | 219 | b = __pool_refill_alloc(pool_head_buffer, margin); |
Christopher Faulet | fa5c812 | 2017-11-10 10:39:16 +0100 | [diff] [blame] | 220 | |
Willy Tarreau | f161d0f | 2018-02-22 14:05:55 +0100 | [diff] [blame] | 221 | #ifndef CONFIG_HAP_LOCKLESS_POOLS |
Willy Tarreau | bafbe01 | 2017-11-24 17:34:44 +0100 | [diff] [blame] | 222 | HA_SPIN_UNLOCK(POOL_LOCK, &pool_head_buffer->lock); |
Olivier Houchard | cf975d4 | 2018-01-24 18:38:31 +0100 | [diff] [blame] | 223 | #endif |
Willy Tarreau | f4718e8 | 2014-12-02 13:54:01 +0100 | [diff] [blame] | 224 | |
Christopher Faulet | fa5c812 | 2017-11-10 10:39:16 +0100 | [diff] [blame] | 225 | if (b) { |
Willy Tarreau | bafbe01 | 2017-11-24 17:34:44 +0100 | [diff] [blame] | 226 | b->size = pool_head_buffer->size - sizeof(struct buffer); |
Christopher Faulet | fa5c812 | 2017-11-10 10:39:16 +0100 | [diff] [blame] | 227 | b_reset(b); |
| 228 | *buf = b; |
| 229 | } |
| 230 | return b; |
Willy Tarreau | f4718e8 | 2014-12-02 13:54:01 +0100 | [diff] [blame] | 231 | } |
| 232 | |
Christopher Faulet | a73e59b | 2016-12-09 17:30:18 +0100 | [diff] [blame] | 233 | |
Willy Tarreau | c41b3e8 | 2018-03-02 10:27:12 +0100 | [diff] [blame] | 234 | /* Offer a buffer currently belonging to target <from> to whoever needs one. |
| 235 | * Any pointer is valid for <from>, including NULL. Its purpose is to avoid |
| 236 | * passing a buffer to oneself in case of failed allocations (e.g. need two |
| 237 | * buffers, get one, fail, release it and wake up self again). In case of |
| 238 | * normal buffer release where it is expected that the caller is not waiting |
| 239 | * for a buffer, NULL is fine. |
| 240 | */ |
Christopher Faulet | a73e59b | 2016-12-09 17:30:18 +0100 | [diff] [blame] | 241 | void __offer_buffer(void *from, unsigned int threshold); |
| 242 | |
| 243 | static inline void offer_buffers(void *from, unsigned int threshold) |
| 244 | { |
Christopher Faulet | 2a944ee | 2017-11-07 10:42:54 +0100 | [diff] [blame] | 245 | HA_SPIN_LOCK(BUF_WQ_LOCK, &buffer_wq_lock); |
Emeric Brun | a1dd243 | 2017-06-21 15:42:52 +0200 | [diff] [blame] | 246 | if (LIST_ISEMPTY(&buffer_wq)) { |
Christopher Faulet | 2a944ee | 2017-11-07 10:42:54 +0100 | [diff] [blame] | 247 | HA_SPIN_UNLOCK(BUF_WQ_LOCK, &buffer_wq_lock); |
Christopher Faulet | a73e59b | 2016-12-09 17:30:18 +0100 | [diff] [blame] | 248 | return; |
Emeric Brun | a1dd243 | 2017-06-21 15:42:52 +0200 | [diff] [blame] | 249 | } |
Christopher Faulet | a73e59b | 2016-12-09 17:30:18 +0100 | [diff] [blame] | 250 | __offer_buffer(from, threshold); |
Christopher Faulet | 2a944ee | 2017-11-07 10:42:54 +0100 | [diff] [blame] | 251 | HA_SPIN_UNLOCK(BUF_WQ_LOCK, &buffer_wq_lock); |
Christopher Faulet | a73e59b | 2016-12-09 17:30:18 +0100 | [diff] [blame] | 252 | } |
| 253 | |
Willy Tarreau | e5676e7 | 2017-09-22 15:47:51 +0200 | [diff] [blame] | 254 | |
Willy Tarreau | c7e4238 | 2012-08-24 19:22:53 +0200 | [diff] [blame] | 255 | #endif /* _COMMON_BUFFER_H */ |
| 256 | |
| 257 | /* |
| 258 | * Local variables: |
| 259 | * c-indent-level: 8 |
| 260 | * c-basic-offset: 8 |
| 261 | * End: |
| 262 | */ |