d6b4206841
Add tests for perf event array with and without BPF_F_PRESERVE_ELEMS. Add a perf event to array via fd mfd. Without BPF_F_PRESERVE_ELEMS, the perf event is removed when mfd is closed. With BPF_F_PRESERVE_ELEMS, the perf event is removed when the map is freed. Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200930224927.1936644-3-songliubraving@fb.com
39 lines
893 B
C
39 lines
893 B
C
// SPDX-License-Identifier: GPL-2.0
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// Copyright (c) 2020 Facebook
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#include <linux/bpf.h>
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#include <bpf/bpf_helpers.h>
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#include <bpf/bpf_tracing.h>
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struct {
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__uint(type, BPF_MAP_TYPE_PERF_EVENT_ARRAY);
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__uint(max_entries, 1);
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__uint(key_size, sizeof(int));
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__uint(value_size, sizeof(int));
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} array_1 SEC(".maps");
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struct {
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__uint(type, BPF_MAP_TYPE_PERF_EVENT_ARRAY);
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__uint(max_entries, 1);
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__uint(key_size, sizeof(int));
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__uint(value_size, sizeof(int));
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__uint(map_flags, BPF_F_PRESERVE_ELEMS);
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} array_2 SEC(".maps");
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SEC("raw_tp/sched_switch")
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int BPF_PROG(read_array_1)
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{
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struct bpf_perf_event_value val;
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return bpf_perf_event_read_value(&array_1, 0, &val, sizeof(val));
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}
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SEC("raw_tp/task_rename")
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int BPF_PROG(read_array_2)
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{
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struct bpf_perf_event_value val;
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return bpf_perf_event_read_value(&array_2, 0, &val, sizeof(val));
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}
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char LICENSE[] SEC("license") = "GPL";
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