linux/kernel/bpf
Andrey Ignatov 1020c1f24a bpf: Simplify __cgroup_bpf_attach
__cgroup_bpf_attach has a lot of identical code to handle two scenarios:
BPF_F_ALLOW_MULTI is set and unset.

Simplify it by splitting the two main steps:

* First, the decision is made whether a new bpf_prog_list entry should
  be allocated or existing entry should be reused for the new program.
  This decision is saved in replace_pl pointer;

* Next, replace_pl pointer is used to handle both possible states of
  BPF_F_ALLOW_MULTI flag (set / unset) instead of doing similar work for
  them separately.

This splitting, in turn, allows to make further simplifications:

* The check for attaching same program twice in BPF_F_ALLOW_MULTI mode
  can be done before allocating cgroup storage, so that if user tries to
  attach same program twice no alloc/free happens as it was before;

* pl_was_allocated becomes redundant so it's removed.

Signed-off-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/c6193db6fe630797110b0d3ff06c125d093b834c.1576741281.git.rdna@fb.com
2019-12-19 21:22:25 -08:00
..
arraymap.c bpf: Simplify __bpf_arch_text_poke poke type handling 2019-11-24 17:12:11 -08:00
bpf_lru_list.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 206 2019-05-30 11:29:53 -07:00
bpf_lru_list.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 206 2019-05-30 11:29:53 -07:00
btf.c bpf: Fix build in minimal configurations 2019-11-29 01:03:42 +01:00
cgroup.c bpf: Simplify __cgroup_bpf_attach 2019-12-19 21:22:25 -08:00
core.c bpf: Remove unnecessary assertion on fp_old 2019-12-19 22:24:15 +01:00
cpumap.c xdp: Make cpumap flush_list common for all map instances 2019-12-19 21:09:43 -08:00
devmap.c xdp: Make devmap flush_list common for all map instances 2019-12-19 21:09:43 -08:00
disasm.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 295 2019-06-05 17:36:38 +02:00
disasm.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 295 2019-06-05 17:36:38 +02:00
dispatcher.c bpf: Introduce BPF dispatcher 2019-12-13 13:09:32 -08:00
hashtab.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-06-17 20:20:36 -07:00
helpers.c cgroup: use cgrp->kn->id as the cgroup ID 2019-11-12 08:18:04 -08:00
inode.c bpf: Convert bpf_prog refcnt to atomic64_t 2019-11-18 11:41:59 +01:00
local_storage.c cgroup: use cgrp->kn->id as the cgroup ID 2019-11-12 08:18:04 -08:00
lpm_trie.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-06-22 08:59:24 -04:00
Makefile bpf: Introduce BPF dispatcher 2019-12-13 13:09:32 -08:00
map_in_map.c bpf: Move owner type, jited info into array auxiliary data 2019-11-24 17:04:11 -08:00
map_in_map.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 206 2019-05-30 11:29:53 -07:00
offload.c bpf, offload: Unlock on error in bpf_offload_dev_create() 2019-11-07 00:20:27 +01:00
percpu_freelist.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 206 2019-05-30 11:29:53 -07:00
percpu_freelist.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 206 2019-05-30 11:29:53 -07:00
queue_stack_maps.c bpf: move memory size checks to bpf_map_charge_init() 2019-05-31 16:52:56 -07:00
reuseport_array.c bpf: move memory size checks to bpf_map_charge_init() 2019-05-31 16:52:56 -07:00
stackmap.c Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-12-03 09:29:50 -08:00
syscall.c bpf, xdp: Start using the BPF dispatcher for XDP 2019-12-13 13:09:32 -08:00
sysfs_btf.c btf: fix return value check in btf_vmlinux_init() 2019-08-15 22:18:17 -07:00
tnum.c treewide: Add SPDX license identifier for missed files 2019-05-21 10:50:45 +02:00
trampoline.c bpf: Move trampoline JIT image allocation to a function 2019-12-13 13:09:32 -08:00
verifier.c bpf: Fix a bug when getting subprog 0 jited image in check_attach_btf_id 2019-12-04 21:20:07 -08:00
xskmap.c xsk: Make xskmap flush_list common for all map instances 2019-12-19 21:09:43 -08:00