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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
commit | 76cb841cb886eef6b3bee341a2266c76578724ad (patch) | |
tree | f5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /tools/testing/selftests/bpf/test_stacktrace_build_id.c | |
parent | Initial commit. (diff) | |
download | linux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip |
Adding upstream version 4.19.249.upstream/4.19.249
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'tools/testing/selftests/bpf/test_stacktrace_build_id.c')
-rw-r--r-- | tools/testing/selftests/bpf/test_stacktrace_build_id.c | 76 |
1 files changed, 76 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/test_stacktrace_build_id.c b/tools/testing/selftests/bpf/test_stacktrace_build_id.c new file mode 100644 index 000000000..d86c281e9 --- /dev/null +++ b/tools/testing/selftests/bpf/test_stacktrace_build_id.c @@ -0,0 +1,76 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (c) 2018 Facebook + +#include <linux/bpf.h> +#include "bpf_helpers.h" + +#ifndef PERF_MAX_STACK_DEPTH +#define PERF_MAX_STACK_DEPTH 127 +#endif + +struct bpf_map_def SEC("maps") control_map = { + .type = BPF_MAP_TYPE_ARRAY, + .key_size = sizeof(__u32), + .value_size = sizeof(__u32), + .max_entries = 1, +}; + +struct bpf_map_def SEC("maps") stackid_hmap = { + .type = BPF_MAP_TYPE_HASH, + .key_size = sizeof(__u32), + .value_size = sizeof(__u32), + .max_entries = 16384, +}; + +struct bpf_map_def SEC("maps") stackmap = { + .type = BPF_MAP_TYPE_STACK_TRACE, + .key_size = sizeof(__u32), + .value_size = sizeof(struct bpf_stack_build_id) + * PERF_MAX_STACK_DEPTH, + .max_entries = 128, + .map_flags = BPF_F_STACK_BUILD_ID, +}; + +struct bpf_map_def SEC("maps") stack_amap = { + .type = BPF_MAP_TYPE_ARRAY, + .key_size = sizeof(__u32), + .value_size = sizeof(struct bpf_stack_build_id) + * PERF_MAX_STACK_DEPTH, + .max_entries = 128, +}; + +/* taken from /sys/kernel/debug/tracing/events/random/urandom_read/format */ +struct random_urandom_args { + unsigned long long pad; + int got_bits; + int pool_left; + int input_left; +}; + +SEC("tracepoint/random/urandom_read") +int oncpu(struct random_urandom_args *args) +{ + __u32 max_len = sizeof(struct bpf_stack_build_id) + * PERF_MAX_STACK_DEPTH; + __u32 key = 0, val = 0, *value_p; + void *stack_p; + + value_p = bpf_map_lookup_elem(&control_map, &key); + if (value_p && *value_p) + return 0; /* skip if non-zero *value_p */ + + /* The size of stackmap and stackid_hmap should be the same */ + key = bpf_get_stackid(args, &stackmap, BPF_F_USER_STACK); + if ((int)key >= 0) { + bpf_map_update_elem(&stackid_hmap, &key, &val, 0); + stack_p = bpf_map_lookup_elem(&stack_amap, &key); + if (stack_p) + bpf_get_stack(args, stack_p, max_len, + BPF_F_USER_STACK | BPF_F_USER_BUILD_ID); + } + + return 0; +} + +char _license[] SEC("license") = "GPL"; +__u32 _version SEC("version") = 1; /* ignored by tracepoints, required by libbpf.a */ |