xref: /dpdk/lib/reorder/rte_reorder.h (revision b4f0a9bb5807a4f0a4904595bb85a9a386696311)
1 /* SPDX-License-Identifier: BSD-3-Clause
2  * Copyright(c) 2010-2014 Intel Corporation
3  */
4 
5 #ifndef _RTE_REORDER_H_
6 #define _RTE_REORDER_H_
7 
8 /**
9  * @file
10  * RTE reorder
11  *
12  * Reorder library is a component which is designed to
13  * provide ordering of out of ordered packets based on
14  * sequence number present in mbuf.
15  */
16 
17 #include <rte_compat.h>
18 #include <rte_mbuf.h>
19 #include <rte_mbuf_dyn.h>
20 
21 #ifdef __cplusplus
22 extern "C" {
23 #endif
24 
25 struct rte_reorder_buffer;
26 
27 typedef uint32_t rte_reorder_seqn_t;
28 extern int rte_reorder_seqn_dynfield_offset;
29 
30 /**
31  * @warning
32  * @b EXPERIMENTAL: this API may change without prior notice
33  *
34  * Read reorder sequence number from mbuf.
35  *
36  * @param mbuf Structure to read from.
37  * @return pointer to reorder sequence number.
38  */
39 __rte_experimental
40 static inline rte_reorder_seqn_t *
rte_reorder_seqn(struct rte_mbuf * mbuf)41 rte_reorder_seqn(struct rte_mbuf *mbuf)
42 {
43 	return RTE_MBUF_DYNFIELD(mbuf, rte_reorder_seqn_dynfield_offset,
44 		rte_reorder_seqn_t *);
45 }
46 
47 /**
48  * Create a new reorder buffer instance
49  *
50  * Allocate memory and initialize a new reorder buffer in that
51  * memory, returning the reorder buffer pointer to the user
52  *
53  * @param name
54  *   The name to be given to the reorder buffer instance.
55  * @param socket_id
56  *   The NUMA node on which the memory for the reorder buffer
57  *   instance is to be reserved.
58  * @param size
59  *   Max number of elements that can be stored in the reorder buffer
60  * @return
61  *   The initialized reorder buffer instance, or NULL on error
62  *   On error case, rte_errno will be set appropriately:
63  *    - ENOMEM - no appropriate memory area found in which to create memzone
64  *    - EINVAL - invalid parameters
65  */
66 struct rte_reorder_buffer *
67 rte_reorder_create(const char *name, unsigned socket_id, unsigned int size);
68 
69 /**
70  * Initializes given reorder buffer instance
71  *
72  * @param b
73  *   Reorder buffer instance to initialize
74  * @param bufsize
75  *   Size of the reorder buffer
76  * @param name
77  *   The name to be given to the reorder buffer
78  * @param size
79  *   Number of elements that can be stored in reorder buffer
80  * @return
81  *   The initialized reorder buffer instance, or NULL on error
82  *   On error case, rte_errno will be set appropriately:
83  *    - EINVAL - invalid parameters
84  *    - ENOMEM - not enough memory to register dynamic field
85  */
86 struct rte_reorder_buffer *
87 rte_reorder_init(struct rte_reorder_buffer *b, unsigned int bufsize,
88 		const char *name, unsigned int size);
89 
90 /**
91  * Find an existing reorder buffer instance
92  * and return a pointer to it.
93  *
94  * @param name
95  *   Name of the reorder buffer instance as passed to rte_reorder_create()
96  * @return
97  *   Pointer to reorder buffer instance or NULL if object not found with rte_errno
98  *   set appropriately. Possible rte_errno values include:
99  *    - ENOENT - required entry not available to return.
100  *    reorder instance list
101  */
102 struct rte_reorder_buffer *
103 rte_reorder_find_existing(const char *name);
104 
105 /**
106  * Reset the given reorder buffer instance with initial values.
107  *
108  * @param b
109  *   Reorder buffer instance which has to be reset
110  */
111 void
112 rte_reorder_reset(struct rte_reorder_buffer *b);
113 
114 /**
115  * Free reorder buffer instance.
116  *
117  * @param b
118  *   Pointer to reorder buffer instance.
119  *   If b is NULL, no operation is performed.
120  */
121 void
122 rte_reorder_free(struct rte_reorder_buffer *b);
123 
124 /**
125  * Insert given mbuf in reorder buffer in its correct position
126  *
127  * The given mbuf is to be reordered relative to other mbufs in the system.
128  * The mbuf must contain a sequence number which is then used to place
129  * the buffer in the correct position in the reorder buffer. Reordered
130  * packets can later be taken from the buffer using the rte_reorder_drain()
131  * API.
132  *
133  * @param b
134  *   Reorder buffer where the mbuf has to be inserted.
135  * @param mbuf
136  *   mbuf of packet that needs to be inserted in reorder buffer.
137  * @return
138  *   0 on success
139  *   -1 on error
140  *   On error case, rte_errno will be set appropriately:
141  *    - ENOSPC - Cannot move existing mbufs from reorder buffer to accommodate
142  *      early mbuf, but it can be accommodated by performing drain and then insert.
143  *    - ERANGE - Too early or late mbuf which is vastly out of range of expected
144  *      window should be ignored without any handling.
145  */
146 int
147 rte_reorder_insert(struct rte_reorder_buffer *b, struct rte_mbuf *mbuf);
148 
149 /**
150  * Fetch reordered buffers
151  *
152  * Returns a set of in-order buffers from the reorder buffer structure. Gaps
153  * may be present in the sequence numbers of the mbuf if packets have been
154  * delayed too long before reaching the reorder window, or have been previously
155  * dropped by the system.
156  *
157  * @param b
158  *   Reorder buffer instance from which packets are to be drained
159  * @param mbufs
160  *   array of mbufs where reordered packets will be inserted from reorder buffer
161  * @param max_mbufs
162  *   the number of elements in the mbufs array.
163  * @return
164  *   number of mbuf pointers written to mbufs. 0 <= N < max_mbufs.
165  */
166 unsigned int
167 rte_reorder_drain(struct rte_reorder_buffer *b, struct rte_mbuf **mbufs,
168 		unsigned max_mbufs);
169 
170 /**
171  * @warning
172  * @b EXPERIMENTAL: this API may change without prior notice
173  *
174  * Fetch set of reordered packets up to specified sequence number (exclusive).
175  *
176  * Returns a set of in-order packets from the reorder buffer structure.
177  * Gaps may be present since reorder buffer will try to fetch
178  * all possible packets up to given sequence number.
179  *
180  * @param b
181  *   Reorder buffer instance from which packets are to be drained.
182  * @param mbufs
183  *   Array of mbufs where reordered packets will be inserted from reorder buffer.
184  * @param max_mbufs
185  *   The number of elements in the mbuf array.
186  * @param seqn
187  *   Sequence number up to which buffer will be drained.
188  * @return
189  *   Number of mbuf pointers written to mbufs. 0 <= N < max_mbufs.
190  */
191 __rte_experimental
192 unsigned int
193 rte_reorder_drain_up_to_seqn(struct rte_reorder_buffer *b, struct rte_mbuf **mbufs,
194 		unsigned int max_mbufs, rte_reorder_seqn_t seqn);
195 
196 /**
197  * @warning
198  * @b EXPERIMENTAL: this API may change without prior notice
199  *
200  * Set minimum sequence number of packet allowed to be buffered.
201  * To successfully set new value,
202  * reorder buffer has to be empty (after create, reset or drain_all).
203  *
204  * @param b
205  *   Empty reorder buffer instance to modify.
206  * @param min_seqn
207  *   New sequence number to set.
208  * @return
209  *   0 on success, a negative value otherwise.
210  */
211 __rte_experimental
212 unsigned int
213 rte_reorder_min_seqn_set(struct rte_reorder_buffer *b, rte_reorder_seqn_t min_seqn);
214 
215 /**
216  * @warning
217  * @b EXPERIMENTAL: this API may change without prior notice
218  *
219  * Determine the amount of memory needed by the reorder buffer
220  * to accommodate a given number of elements.
221  * @see rte_reorder_init()
222  *
223  * @param size
224  *   Number of elements that can be stored in reorder buffer.
225  * @return
226  *   Reorder buffer footprint measured in bytes.
227  */
228 __rte_experimental
229 unsigned int
230 rte_reorder_memory_footprint_get(unsigned int size);
231 
232 #ifdef __cplusplus
233 }
234 #endif
235 
236 #endif /* _RTE_REORDER_H_ */
237