1 #ifndef __sack_filter_h__
2 #define __sack_filter_h__
4 * Copyright (c) 2017-9 Netflix, Inc.
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
15 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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27 * __FBSDID("$FreeBSD$");
31 * Seven entry's is carefully choosen to
32 * fit in one cache line. We can easily
33 * change this to 15 (but it gets very
34 * little extra filtering). To change it
35 * to be larger than 15 would require either
36 * sf_bits becoming a uint32_t and then you
37 * could go to 31.. or change it to a full
38 * bitstring.. It is really doubtful you
39 * will get much benefit beyond 7, in testing
40 * there was a small amount but very very small.
42 #define SACK_FILTER_BLOCKS 7
49 struct sackblk sf_blks[SACK_FILTER_BLOCKS];
52 void sack_filter_clear(struct sack_filter *sf, tcp_seq seq);
53 int sack_filter_blks(struct sack_filter *sf, struct sackblk *in, int numblks,
55 void sack_filter_reject(struct sack_filter *sf, struct sackblk *in);