1 /* 2 * Copyright (c) 2013-2019, Intel Corporation 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions are met: 6 * 7 * * Redistributions of source code must retain the above copyright notice, 8 * this list of conditions and the following disclaimer. 9 * * Redistributions in binary form must reproduce the above copyright notice, 10 * this list of conditions and the following disclaimer in the documentation 11 * and/or other materials provided with the distribution. 12 * * Neither the name of Intel Corporation nor the names of its contributors 13 * may be used to endorse or promote products derived from this software 14 * without specific prior written permission. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 17 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 20 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 26 * POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29 #ifndef PT_TNT_CACHE_H 30 #define PT_TNT_CACHE_H 31 32 #include <stdint.h> 33 34 struct pt_packet_tnt; 35 struct pt_config; 36 37 38 /* Keeping track of tnt indicators. */ 39 struct pt_tnt_cache { 40 /* The last tnt. */ 41 uint64_t tnt; 42 43 /* The index into the above tnt. 44 * 45 * (tnt & index) gives the current tnt entry. 46 * (index >>= 1) moves the index to the next tnt entry. 47 * (index == 0) means that the current tnt is empty. 48 */ 49 uint64_t index; 50 }; 51 52 53 /* Initialize (or reset) the tnt cache. */ 54 extern void pt_tnt_cache_init(struct pt_tnt_cache *cache); 55 56 /* Check if the tnt cache is empty. 57 * 58 * Returns 0 if the tnt cache is not empty. 59 * Returns > 0 if the tnt cache is empty. 60 * Returns -pte_invalid if @cache is NULL. 61 */ 62 extern int pt_tnt_cache_is_empty(const struct pt_tnt_cache *cache); 63 64 /* Query the next tnt indicator. 65 * 66 * This consumes the returned tnt indicator in the cache. 67 * 68 * Returns 0 if the next branch is not taken. 69 * Returns > 0 if the next branch is taken. 70 * Returns -pte_invalid if @cache is NULL. 71 * Returns -pte_bad_query if there is no tnt cached. 72 */ 73 extern int pt_tnt_cache_query(struct pt_tnt_cache *cache); 74 75 /* Update the tnt cache based on Intel PT packets. 76 * 77 * Updates @cache based on @packet and, if non-null, @config. 78 * 79 * Returns zero on success. 80 * Returns -pte_invalid if @cache or @packet is NULL. 81 * Returns -pte_bad_packet if @packet appears to be corrupted. 82 * Returns -pte_bad_context if the tnt cache is not empty. 83 */ 84 extern int pt_tnt_cache_update_tnt(struct pt_tnt_cache *cache, 85 const struct pt_packet_tnt *packet, 86 const struct pt_config *config); 87 88 #endif /* PT_TNT_CACHE_H */ 89