18–20 Sept 2024
Europe/Vienna timezone

Kernel func tracing in the face of compiler optimization

19 Sept 2024, 16:00
30m
"Hall N1" (Austria Center)

"Hall N1"

Austria Center

180
eBPF Track eBPF Track

Speakers

Yonghong Song (Meta) Alan Maguire (Oracle)

Description

Bpf provides ability to trace kernel functions (kprobe, kretprobe, fentry and fexit) and users often use such features to do kernel function tracing in order to gather information for their particular needs. But compiler optimization may make kernel func tracing difficulty. For example, complete inlining may make function going away in symbol table. Partial inlining may leave functions in certain original call site but not others. Compiler may also make changes to function parameters or introduce suffix to original function name in order to signal scope/functionality change for those functions. In this talk, we will discuss different cases how compiler optimization impacts kernel function tracing and if possible how to cope with them.

Primary authors

Presentation materials