8df839ae23
bpf_arena_htab.h - hash table implemented as bpf program Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20240308010812.89848-15-alexei.starovoitov@gmail.com
49 lines
1.0 KiB
C
49 lines
1.0 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/* Copyright (c) 2024 Meta Platforms, Inc. and affiliates. */
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#include <vmlinux.h>
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#include <bpf/bpf_helpers.h>
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#include <bpf/bpf_tracing.h>
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#include <bpf/bpf_core_read.h>
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#include "bpf_experimental.h"
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struct {
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__uint(type, BPF_MAP_TYPE_ARENA);
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__uint(map_flags, BPF_F_MMAPABLE);
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__uint(max_entries, 100); /* number of pages */
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} arena SEC(".maps");
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#include "bpf_arena_htab.h"
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void __arena *htab_for_user;
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bool skip = false;
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int zero = 0;
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SEC("syscall")
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int arena_htab_llvm(void *ctx)
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{
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#if defined(__BPF_FEATURE_ARENA_CAST) || defined(BPF_ARENA_FORCE_ASM)
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struct htab __arena *htab;
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__u64 i;
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htab = bpf_alloc(sizeof(*htab));
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cast_kern(htab);
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htab_init(htab);
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/* first run. No old elems in the table */
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for (i = zero; i < 1000; i++)
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htab_update_elem(htab, i, i);
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/* should replace all elems with new ones */
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for (i = zero; i < 1000; i++)
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htab_update_elem(htab, i, i);
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cast_user(htab);
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htab_for_user = htab;
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#else
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skip = true;
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#endif
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return 0;
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}
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char _license[] SEC("license") = "GPL";
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