minutes: IO Visor TSC/Dev Meeting

Brenden Blanco

Hi All,

Thanks for dialing in to the meeting today. Here are my notes from the


=== Discussion ===
- Discussion with some kernel devs regarding BPF memory model
- some documentation to be done
- (currently avoiding uapi enforcement on content of bpf program itself)
- introduce standard header file for bpf programs to include
- add read_once, write_once primitive
- llvm will understand this
- 64 bit jit must implement these instructions

LSFMM will have a BPF track
- CFP closes this Friday, send your proposals if you have them
- Or send an email if you simply wish to attend

- LPC discussion followup - metadata parsing in hardware
- way to notify/raise events userspace of new flow marks detected and trigger
injection of tc rule?
- use perf ring buffer, available in kernel samples/

- bpftrace function tracing use case in java
- needs couple fixes
- uprobe to be able to attach heap locations instead of inode-only
- tell c2 compiler to pause moving functions around
- looking for ways to get past libc/libpthread backtrace walking (usually
compiled without frame pointer)
- hoping for Intel LBR support, but not available in many cloud VMs yet

=== Attendees ===
Brenden Blanco
Andrii Nakryiko
Dan Siemon
Marco Leogrande
Jesper Brouer
Jerome Marchand
Tom Stellard
Jakub Kicinski
Bjorn Topel
Martin Lau
Andy Gospodarek
Paul Chaignon
Jiong Wang
Alexei Starovoitov
Daniel Borkmann
Quentin Monnet
Mauricio Vasquez
Matheus Marchini
Joe Stringer
Brendan Gregg