Commit Graph
2 Commits
Author SHA1 Message Date
Menglong Dong cc7177624f libbpf: Add support to set kprobe/uprobe attach mode
By default, libbpf will attach the kprobe/uprobe BPF program in the
latest mode that supported by kernel. In this patch, we add the support
to let users manually attach kprobe/uprobe in legacy or perf mode.

There are 3 mode that supported by the kernel to attach kprobe/uprobe:

  LEGACY: create perf event in legacy way and don't use bpf_link
  PERF: create perf event with perf_event_open() and don't use bpf_link

Signed-off-by: Menglong Dong <imagedong@tencent.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Biao Jiang <benbjiang@tencent.com>
Link: create perf event with perf_event_open() and use bpf_link
Link: https://lore.kernel.org/bpf/20230113093427.1666466-1-imagedong@tencent.com/
Link: https://lore.kernel.org/bpf/20230306064833.7932-2-imagedong@tencent.com

Users now can manually choose the mode with
bpf_program__attach_uprobe_opts()/bpf_program__attach_kprobe_opts().
2023-03-15 13:18:34 -07:00
Menglong Dong 49e950dcfa libbpf: Replace '.' with '_' in legacy kprobe event name
'.' is not allowed in the event name of kprobe. Therefore, we will get a
EINVAL if the kernel function name has a '.' in legacy kprobe attach
case, such as 'icmp_reply.constprop.0'.

In order to adapt this case, we need to replace the '.' with other char
in gen_kprobe_legacy_event_name(). And I use '_' for this propose.

Signed-off-by: Menglong Dong <imagedong@tencent.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Alan Maguire <alan.maguire@oracle.com>
Link: https://lore.kernel.org/bpf/20230113093427.1666466-1-imagedong@tencent.com
2023-01-25 20:44:09 -08:00