[PATCH bpf-next 0/3] writable contexts for bpf raw tracepoints

From: Matt Mullins
Date: Thu Mar 28 2019 - 20:08:38 EST


This adds an opt-in interface for tracepoints to expose a writable context to
BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE programs that are attached, while
supporting read-only access from existing BPF_PROG_TYPE_RAW_TRACEPOINT
programs, as well as from non-BPF-based tracepoints.

The initial motivation is to support tracing that can be observed from the
remote end of an NBD socket, e.g. by adding flags to the struct nbd_request
header. Earlier attempts included adding an NBD-specific tracepoint fd, but in
code review, I was recommended to implement it more generically -- as a result,
this patchset is far simpler than my initial try.

Andrew Hall (1):
nbd: add tracepoints for send/receive timing

Matt Mullins (2):
bpf: add writable context for raw tracepoints
nbd: trace sending nbd requests

MAINTAINERS | 1 +
drivers/block/nbd.c | 13 +++
include/linux/bpf.h | 2 +
include/linux/bpf_types.h | 1 +
include/linux/tracepoint-defs.h | 1 +
include/trace/bpf_probe.h | 27 +++++-
include/trace/events/nbd.h | 148 ++++++++++++++++++++++++++++++++
include/uapi/linux/bpf.h | 1 +
kernel/bpf/syscall.c | 8 +-
kernel/bpf/verifier.c | 11 +++
kernel/trace/bpf_trace.c | 21 +++++
11 files changed, 230 insertions(+), 4 deletions(-)
create mode 100644 include/trace/events/nbd.h

--
2.17.1