Re: [PATCH v7 bpf-next 06/10] tracepoint: compute num_args at build time
From: Steven Rostedt <rostedt@goodmis.org>
Date: 2018-03-28 17:38:34
Also in:
linux-api
From: Steven Rostedt <rostedt@goodmis.org>
Date: 2018-03-28 17:38:34
Also in:
linux-api
On Wed, 28 Mar 2018 10:10:34 -0700 Alexei Starovoitov [off-list ref] wrote:
quoted
and have: u64 tp_offset = (u64)tp - (u64)_sdata; if (WARN_ON(tp_offset > UINT_MAX) return -EINVAL; btp->tp_offset = (u32)tp_offset;above math has to be build time constant, so warn_on likely won't work.
Right, it would require a BUILD_BUG_ON.
imo the whole thing is too fragile and obscure. I suggest to compress this 8 bytes * num_of_tracepoints later. Especially would be good to do it in one way for bpf_raw_event_map, ftrace and other places.
Fair enough. We can defer this shrinkage to another time. I only suggested it here over your concern for the added bloat. -- Steve