mirror of
https://github.com/torvalds/linux.git
synced 2024-12-05 02:23:16 +00:00
3677d0a131
For the problem of increasing fragmentation of the bpf loader programs, instead of using bpf_loader.o, which is used in samples/bpf, this commit refactors the existing kprobe tracing programs with libbbpf bpf loader. - For kprobe events pointing to system calls, the SYSCALL() macro in trace_common.h was used. - Adding a kprobe event and attaching a bpf program to it was done through bpf_program_attach(). - Instead of using the existing BPF MAP definition, MAP definition has been refactored with the new BTF-defined MAP format. Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200823085334.9413-3-danieltimlee@gmail.com
45 lines
1.1 KiB
C
45 lines
1.1 KiB
C
/* Copyright (c) 2016 Sargun Dhillon <sargun@sargun.me>
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of version 2 of the GNU General Public
|
|
* License as published by the Free Software Foundation.
|
|
*/
|
|
|
|
#include <linux/ptrace.h>
|
|
#include <uapi/linux/bpf.h>
|
|
#include <linux/version.h>
|
|
#include <bpf/bpf_helpers.h>
|
|
#include <uapi/linux/utsname.h>
|
|
#include "trace_common.h"
|
|
|
|
struct {
|
|
__uint(type, BPF_MAP_TYPE_CGROUP_ARRAY);
|
|
__uint(key_size, sizeof(u32));
|
|
__uint(value_size, sizeof(u32));
|
|
__uint(max_entries, 1);
|
|
} cgroup_map SEC(".maps");
|
|
|
|
struct {
|
|
__uint(type, BPF_MAP_TYPE_ARRAY);
|
|
__type(key, u32);
|
|
__type(value, u64);
|
|
__uint(max_entries, 1);
|
|
} perf_map SEC(".maps");
|
|
|
|
/* Writes the last PID that called sync to a map at index 0 */
|
|
SEC("kprobe/" SYSCALL(sys_sync))
|
|
int bpf_prog1(struct pt_regs *ctx)
|
|
{
|
|
u64 pid = bpf_get_current_pid_tgid();
|
|
int idx = 0;
|
|
|
|
if (!bpf_current_task_under_cgroup(&cgroup_map, 0))
|
|
return 0;
|
|
|
|
bpf_map_update_elem(&perf_map, &idx, &pid, BPF_ANY);
|
|
return 0;
|
|
}
|
|
|
|
char _license[] SEC("license") = "GPL";
|
|
u32 _version SEC("version") = LINUX_VERSION_CODE;
|