On Sat, Jan 9, 2021 at 12:35 AM Song Liu <songliubrav...@fb.com> wrote: > > To access per-task data, BPF program typically creates a hash table with > pid as the key. This is not ideal because: > 1. The use need to estimate requires size of the hash table, with may be > inaccurate; > 2. Big hash tables are slow; > 3. To clean up the data properly during task terminations, the user need > to write code. > > Task local storage overcomes these issues and becomes a better option for > these per-task data. Task local storage is only available to BPF_LSM. Now > enable it for tracing programs.
Also mention here that you change the pointer from being a security blob to a dedicated member in the task struct. I assume this is because you want to use it without CONFIG_BPF_LSM? > Can you also mention the reasons for changing the raw_spin_lock_bh to raw_spin_lock_irqsave in the commit log? > Reported-by: kernel test robot <l...@intel.com> > Signed-off-by: Song Liu <songliubrav...@fb.com> > --- > include/linux/bpf.h | 7 +++++++ > include/linux/bpf_lsm.h | 22 ---------------------- > include/linux/bpf_types.h | 2 +- > include/linux/sched.h | 5 +++++ > kernel/bpf/Makefile | 3 +-- > kernel/bpf/bpf_local_storage.c | 28 +++++++++++++++++----------- > kernel/bpf/bpf_lsm.c | 4 ---- > kernel/bpf/bpf_task_storage.c | 26 ++++++-------------------- > kernel/fork.c | 5 +++++ > kernel/trace/bpf_trace.c | 4 ++++ > 10 files changed, 46 insertions(+), 60 deletions(-) > [...]
