linux/kernel/bpf
Alexei Starovoitov 324bda9e6c bpf: multi program support for cgroup+bpf
introduce BPF_F_ALLOW_MULTI flag that can be used to attach multiple
bpf programs to a cgroup.

The difference between three possible flags for BPF_PROG_ATTACH command:
- NONE(default): No further bpf programs allowed in the subtree.
- BPF_F_ALLOW_OVERRIDE: If a sub-cgroup installs some bpf program,
  the program in this cgroup yields to sub-cgroup program.
- BPF_F_ALLOW_MULTI: If a sub-cgroup installs some bpf program,
  that cgroup program gets run in addition to the program in this cgroup.

NONE and BPF_F_ALLOW_OVERRIDE existed before. This patch doesn't
change their behavior. It only clarifies the semantics in relation
to new flag.

Only one program is allowed to be attached to a cgroup with
NONE or BPF_F_ALLOW_OVERRIDE flag.
Multiple programs are allowed to be attached to a cgroup with
BPF_F_ALLOW_MULTI flag. They are executed in FIFO order
(those that were attached first, run first)
The programs of sub-cgroup are executed first, then programs of
this cgroup and then programs of parent cgroup.
All eligible programs are executed regardless of return code from
earlier programs.

To allow efficient execution of multiple programs attached to a cgroup
and to avoid penalizing cgroups without any programs attached
introduce 'struct bpf_prog_array' which is RCU protected array
of pointers to bpf programs.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
for cgroup bits
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-04 16:05:05 -07:00
..
arraymap.c bpf: inline map in map lookup functions for array and htab 2017-08-19 21:56:34 -07:00
bpf_lru_list.c bpf: lru: Lower the PERCPU_NR_SCANS from 16 to 4 2017-04-17 13:55:52 -04:00
bpf_lru_list.h bpf: Only set node->ref = 1 if it has not been set 2017-09-01 09:57:39 -07:00
cgroup.c bpf: multi program support for cgroup+bpf 2017-10-04 16:05:05 -07:00
core.c bpf: multi program support for cgroup+bpf 2017-10-04 16:05:05 -07:00
devmap.c bpf: devmap: pass on return value of bpf_map_precharge_memlock 2017-09-18 16:53:30 -07:00
hashtab.c bpf: Only set node->ref = 1 if it has not been set 2017-09-01 09:57:39 -07:00
helpers.c bpf: rename ARG_PTR_TO_STACK 2017-01-09 16:56:27 -05:00
inode.c bpf: Implement show_options 2017-07-06 03:31:46 -04:00
lpm_trie.c bpf: Optimize lpm trie delete 2017-09-25 14:37:54 -07:00
Makefile bpf: sock_map fixes for !CONFIG_BPF_SYSCALL and !STREAM_PARSER 2017-08-16 15:34:13 -07:00
map_in_map.c bpf: Add syscall lookup support for fd array and htab 2017-06-29 13:13:25 -04:00
map_in_map.h bpf: Add syscall lookup support for fd array and htab 2017-06-29 13:13:25 -04:00
percpu_freelist.c bpf: introduce percpu_freelist 2016-03-08 15:28:31 -05:00
percpu_freelist.h bpf: introduce percpu_freelist 2016-03-08 15:28:31 -05:00
sockmap.c bpf: rename bpf_compute_data_end into bpf_compute_data_pointers 2017-09-26 13:36:44 -07:00
stackmap.c bpf: Allow selecting numa node during map creation 2017-08-19 21:35:43 -07:00
syscall.c bpf: multi program support for cgroup+bpf 2017-10-04 16:05:05 -07:00
tnum.c bpf/verifier: track signed and unsigned min/max values 2017-08-08 17:51:34 -07:00
verifier.c bpf/verifier: improve disassembly of BPF_NEG instructions 2017-09-28 10:23:18 -07:00