On Thu, May 1, 2025, at 7:28 AM, Lorenz Bauer wrote:
I'd like to cut down the memory usage of parsing vmlinux BTF in ebpf-go. With some upcoming changes the library is sitting at 5MiB for a parse. Most of that memory is simply copying the BTF blob into user space. By allowing vmlinux BTF to be mmapped read-only into user space I can cut memory usage by about 75%.
Cool! Maybe teach libbpf to use this as well? So everyone else can pick up the win transparently.
Signed-off-by: Lorenz Bauer lmb@isovalent.com
Lorenz Bauer (2): btf: allow mmap of vmlinux btf selftests: bpf: add a test for mmapable vmlinux BTF
include/asm-generic/vmlinux.lds.h | 3 +- kernel/bpf/sysfs_btf.c | 25 ++++++- tools/testing/selftests/bpf/prog_tests/btf_sysfs.c | 79 ++++++++++++++++++++++ 3 files changed, 104 insertions(+), 3 deletions(-)
base-commit: 38d976c32d85ef12dcd2b8a231196f7049548477 change-id: 20250501-vmlinux-mmap-2ec5563c3ef1
Best regards,
Lorenz Bauer lmb@isovalent.com