On 2022/8/27 13:12, Andrii Nakryiko wrote:
On Fri, Aug 26, 2022 at 3:45 AM Quentin Monnet <quentin@xxxxxxxxxxxxx> wrote:
Hi Andrii,
On 25/08/2022 19:37, Andrii Nakryiko wrote:
On Thu, Aug 25, 2022 at 8:28 AM Quentin Monnet <quentin@xxxxxxxxxxxxx> wrote:
Hi Wei,
Apologies for failing to answer to your previous email and for the delay
on this one, I just found out GMail had classified them as spam :(.
So as for your last message, yes: your understanding of my previous
answer was correct. Thanks for the patch below! Some comments inline.
Do we really want to add such a specific command to bpftool that would
attach BPF object files with programs of only RAW_TRACEPOINT and
RAW_TRACEPOINT_WRITABLE type?
I could understand if we added something that would be equivalent of
BPF skeleton's auto-attach method. That would make sense in some
contexts, especially for some quick testing and validation, to avoid
writing (a rather simple) user-space loading code.
Do you mean loading and attaching in a single step, or keeping the
possibility to load first as in the current proposal?
But "perf attach" for raw_tp programs only? Seem way too limited and
specific, just adding bloat to bpftool, IMO.
We already support attaching some kinds of program types through
"prog|cgroup|net attach". Here I thought we could add support for other
types as a follow-up, but thinking again, you're probably right, it
would be best if all the types were supported from the start. Wei, have
you looked into how much work it would be to add support for
tracepoints, k(ret)probes, u(ret)probes as well? The code should be
mostly identical?
Are you thinking to allow to attach individual BPF programs within BPF
object, i.e., effectively bpftool as an interface to libbpf's
bpf_program__attach()?
My use case is attach/detach individual BPF programs.
We used writeable raw tracepoint in mockup bus controller[1], individual
BPF programs action as different mockup device chips, and the unittest
can be running on the top of mockup device. So BPF programs should be
attach/detach by the test framework.
[1] https://www.spinics.net/lists/kernel/msg4490698.html
Or you had more of BPF skeleton's auto-attach that attaches all
auto-attachable BPF programs?
Regards,
Wei Yongjun
