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// SPDX-License-Identifier: GPL-2.0
/* Copyright (c) 2020 Tessares SA <http://www.tessares.net> */
#include "vmlinux.h"
#include <bpf/bpf_helpers.h>
__u64 inKey = 0;
__u64 inValue = 0;
__u32 inPid = 0;
struct {
__uint(type, BPF_MAP_TYPE_PERCPU_HASH);
__uint(max_entries, 2);
__type(key, __u64);
__type(value, __u64);
} hashmap1 SEC(".maps");
SEC("tp/syscalls/sys_enter_getpgid")
int sysenter_getpgid(const void *ctx)
{
/* Just do it for once, when called from our own test prog. This
* ensures the map value is only updated for a single CPU.
*/
int cur_pid = bpf_get_current_pid_tgid() >> 32;
if (cur_pid == inPid)
bpf_map_update_elem(&hashmap1, &inKey, &inValue, BPF_NOEXIST);
return 0;
}
char _license[] SEC("license") = "GPL";
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