1 /* SPDX-License-Identifier: BSD-3-Clause
2 *
3 * Copyright(c) 2019-2021 Xilinx, Inc.
4 * Copyright(c) 2019 Solarflare Communications Inc.
5 *
6 * This software was jointly developed between OKTET Labs (under contract
7 * for Solarflare) and Solarflare Communications, Inc.
8 */
9
10 #ifndef _SFC_STATS_H
11 #define _SFC_STATS_H
12
13 #include <stdint.h>
14
15 #include <rte_atomic.h>
16
17 #include "sfc_tweak.h"
18
19 #ifdef __cplusplus
20 extern "C" {
21 #endif
22
23 /**
24 * 64-bit packets and bytes counters covered by 128-bit integer
25 * in order to do atomic updates to guarantee consistency if
26 * required.
27 */
28 union sfc_pkts_bytes {
29 RTE_STD_C11
30 struct {
31 uint64_t pkts;
32 uint64_t bytes;
33 };
34 rte_int128_t pkts_bytes;
35 };
36
37 /**
38 * Update packets and bytes counters atomically in assumption that
39 * the counter is written on one core only.
40 */
41 static inline void
sfc_pkts_bytes_add(union sfc_pkts_bytes * st,uint64_t pkts,uint64_t bytes)42 sfc_pkts_bytes_add(union sfc_pkts_bytes *st, uint64_t pkts, uint64_t bytes)
43 {
44 #if SFC_SW_STATS_ATOMIC
45 union sfc_pkts_bytes result;
46
47 /* Stats are written on single core only, so just load values */
48 result.pkts = st->pkts + pkts;
49 result.bytes = st->bytes + bytes;
50
51 /*
52 * Store the result atomically to guarantee that the reader
53 * core sees both counter updates together.
54 */
55 __atomic_store_n(&st->pkts_bytes.int128, result.pkts_bytes.int128,
56 __ATOMIC_RELAXED);
57 #else
58 st->pkts += pkts;
59 st->bytes += bytes;
60 #endif
61 }
62
63 /**
64 * Get an atomic copy of a packets and bytes counters.
65 */
66 static inline void
sfc_pkts_bytes_get(const union sfc_pkts_bytes * st,union sfc_pkts_bytes * result)67 sfc_pkts_bytes_get(const union sfc_pkts_bytes *st, union sfc_pkts_bytes *result)
68 {
69 #if SFC_SW_STATS_ATOMIC
70 result->pkts_bytes.int128 = __atomic_load_n(&st->pkts_bytes.int128,
71 __ATOMIC_RELAXED);
72 #else
73 *result = *st;
74 #endif
75 }
76
77 #ifdef __cplusplus
78 }
79 #endif
80 #endif /* _SFC_STATS_H */
81