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author | Daniel T. Lee <danieltimlee@gmail.com> | 2023-08-18 12:01:13 +0300 |
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committer | Alexei Starovoitov <ast@kernel.org> | 2023-08-22 01:39:09 +0300 |
commit | 4a0ee78890699706f59cc9bdf8283ecaa4e0a141 (patch) | |
tree | b8bde98ddaf00497ce97b2df14735b224bc2d1ef /samples/bpf/tracex1.bpf.c | |
parent | e7e6c774f5d40244444f23b8c49dac2ded158d8c (diff) | |
download | linux-4a0ee78890699706f59cc9bdf8283ecaa4e0a141.tar.xz |
samples/bpf: unify bpf program suffix to .bpf with tracing programs
Currently, BPF programs typically have a suffix of .bpf.c. However,
some programs still utilize a mixture of _kern.c suffix alongside the
naming convention. In order to achieve consistency in the naming of
these programs, this commit unifies the inconsistency in the naming
convention of BPF kernel programs.
Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Link: https://lore.kernel.org/r/20230818090119.477441-4-danieltimlee@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'samples/bpf/tracex1.bpf.c')
-rw-r--r-- | samples/bpf/tracex1.bpf.c | 53 |
1 files changed, 53 insertions, 0 deletions
diff --git a/samples/bpf/tracex1.bpf.c b/samples/bpf/tracex1.bpf.c new file mode 100644 index 000000000000..bb78bdbffa87 --- /dev/null +++ b/samples/bpf/tracex1.bpf.c @@ -0,0 +1,53 @@ +/* Copyright (c) 2013-2015 PLUMgrid, http://plumgrid.com + * + * 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 "vmlinux.h" +#include "net_shared.h" +#include <linux/version.h> +#include <bpf/bpf_helpers.h> +#include <bpf/bpf_tracing.h> + +#define _(P) \ + ({ \ + typeof(P) val = 0; \ + bpf_probe_read_kernel(&val, sizeof(val), &(P)); \ + val; \ + }) + +/* kprobe is NOT a stable ABI + * kernel functions can be removed, renamed or completely change semantics. + * Number of arguments and their positions can change, etc. + * In such case this bpf+kprobe example will no longer be meaningful + */ +SEC("kprobe/__netif_receive_skb_core") +int bpf_prog1(struct pt_regs *ctx) +{ + /* attaches to kprobe __netif_receive_skb_core, + * looks for packets on loobpack device and prints them + */ + char devname[IFNAMSIZ]; + struct net_device *dev; + struct sk_buff *skb; + int len; + + /* non-portable! works for the given kernel only */ + bpf_probe_read_kernel(&skb, sizeof(skb), (void *)PT_REGS_PARM1(ctx)); + dev = _(skb->dev); + len = _(skb->len); + + bpf_probe_read_kernel(devname, sizeof(devname), dev->name); + + if (devname[0] == 'l' && devname[1] == 'o') { + char fmt[] = "skb %p len %d\n"; + /* using bpf_trace_printk() for DEBUG ONLY */ + bpf_trace_printk(fmt, sizeof(fmt), skb, len); + } + + return 0; +} + +char _license[] SEC("license") = "GPL"; +u32 _version SEC("version") = LINUX_VERSION_CODE; |