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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events	SUNRPC: Move the svc_xdr_recvfrom tracepoint again	2021-01-13 09:13:20 -05:00
bpf_probe.h	trace: bpf: Allow bpf to attach to bare tracepoints	2021-01-20 14:13:59 -08:00
define_trace.h	tracepoint: Optimize using static_call()	2020-09-01 09:58:06 +02:00
perf.h
syscall.h	tracepoints: Migrate to use SYSCALL_WORK flag	2020-11-16 21:53:15 +01:00
trace_events.h	treewide: Convert macro and uses of __section(foo) to __section("foo")	2020-10-25 14:51:49 -07:00