1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
|
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2022, 2025, Oracle and/or its affiliates.
*/
#include <linux/bpf.h>
#include <stdint.h>
#include <bpf/bpf_helpers.h>
#include <bpf-lib.h>
#include <dt_bpf_maps.h>
#include <dt_dctx.h>
#ifndef noinline
# define noinline __attribute__((noinline))
#endif
extern struct bpf_map_def agggen;
extern struct bpf_map_def cpuinfo;
/*
* Register an aggregation drop.
*/
noinline uint64_t *dt_no_agg(void)
{
uint32_t key = bpf_get_smp_processor_id();
dt_bpf_cpuinfo_t *ci;
ci = bpf_map_lookup_elem(&cpuinfo, &key);
if (ci == 0)
return 0;
atomic_add(&ci->agg_drops, 1);
return 0;
}
/*
* Get a pointer to the data storage for an aggregation. Regular aggregations
* are stored as an indexed aggregation with an empty key. The 'id' parameter
* is the aggregation id; 'ival' is the initial value for min/max aggregations
* (and otherwise 0). The 'dflt' parameter is a pointer to a zero-filled area
* of memory that is at least the size of the largest aggregation.
*/
noinline uint64_t *dt_get_agg(const dt_dctx_t *dctx, uint32_t id,
const char *key, uint64_t ival, const char *dflt)
{
uint64_t *genp;
uint64_t *valp;
/* get the gen value */
genp = bpf_map_lookup_elem(&agggen, &id);
if (genp == 0)
return dt_no_agg();
/* place the variable ID at the beginning of the key */
*(uint32_t *)key = id;
/* try to look up the key */
valp = bpf_map_lookup_elem(dctx->agg, key);
/* if not found, or older gen, set initial values */
if (valp == 0 || valp[0] < *genp) {
/* start with all zeroes */
if (bpf_map_update_elem(dctx->agg, key, dflt, BPF_ANY) < 0)
return dt_no_agg();
valp = bpf_map_lookup_elem(dctx->agg, key);
if (valp == 0)
return dt_no_agg();
/* ival is nonzero only for min() and max() */
if (ival)
valp[1] = ival;
/* set the gen value */
valp[0] = *genp;
}
/* advance past the data counter */
valp += 1;
return valp;
}
|
