Qais Yousef 6939f4ef16 trace: bpf: Allow bpf to attach to bare tracepoints ... Some subsystems only have bare tracepoints (a tracepoint with no associated trace event) to avoid the problem of trace events being an ABI that can't be changed. >From bpf presepective, bare tracepoints are what it calls RAW_TRACEPOINT(). Since bpf assumed there's 1:1 mapping, it relied on hooking to DEFINE_EVENT() macro to create bpf mapping of the tracepoints. Since bare tracepoints use DECLARE_TRACE() to create the tracepoint, bpf had no knowledge about their existence. By teaching bpf_probe.h to parse DECLARE_TRACE() in a similar fashion to DEFINE_EVENT(), bpf can find and attach to the new raw tracepoints. Enabling that comes with the contract that changes to raw tracepoints don't constitute a regression if they break existing bpf programs. We need the ability to continue to morph and modify these raw tracepoints without worrying about any ABI. Update Documentation/bpf/bpf_design_QA.rst to document this contract. Signed-off-by: Qais Yousef <qais.yousef@arm.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20210119122237.2426878-2-qais.yousef@arm.com		2021-01-20 14:13:59 -08:00
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bpf_design_QA.rst	trace: bpf: Allow bpf to attach to bare tracepoints	2021-01-20 14:13:59 -08:00
bpf_devel_QA.rst	bpf: Migrate from patchwork.ozlabs.org to patchwork.kernel.org.	2020-10-11 22:05:47 +02:00
bpf_lsm.rst	bpf: lsm: Add Documentation	2020-03-30 01:35:12 +02:00
btf.rst	bpf: Update .BTF_ids section in btf.rst with sets info	2020-08-25 15:41:15 -07:00
drgn.rst	bpf: Document bpf_inspect drgn tool	2020-03-26 00:08:36 +01:00
index.rst	bpf: sk_lookup: Add user documentation	2020-08-24 14:46:50 -07:00
map_cgroup_storage.rst	Documentation/bpf: Document CGROUP_STORAGE map type	2020-07-25 20:16:36 -07:00
prog_cgroup_sockopt.rst	bpf: Document optval > PAGE_SIZE behavior for sockopt hooks	2020-06-17 10:54:05 -07:00
prog_cgroup_sysctl.rst	bpf: Document BPF_PROG_TYPE_CGROUP_SYSCTL	2019-04-18 16:05:36 -07:00
prog_flow_dissector.rst	bpf/flow_dissector: add mode to enforce global BPF flow dissector	2019-10-07 20:16:33 -07:00
prog_sk_lookup.rst	bpf: sk_lookup: Add user documentation	2020-08-24 14:46:50 -07:00
ringbuf.rst	docs/bpf: Remove source code links	2020-09-14 18:46:54 -07:00
s390.rst	bpf: Add s390 testing documentation	2019-10-30 16:25:31 +01:00