linux/kernel/bpf
Andrii Nakryiko 618945fbed bpf: remove unnecessary prune and jump points
Don't mark some instructions as jump points when there are actually no
jumps and instructions are just processed sequentially. Such case is
handled naturally by precision backtracking logic without the need to
update jump history. See get_prev_insn_idx(). It goes back linearly by
one instruction, unless current top of jmp_history is pointing to
current instruction. In such case we use `st->jmp_history[cnt - 1].prev_idx`
to find instruction from which we jumped to the current instruction
non-linearly.

Also remove both jump and prune point marking for instruction right
after unconditional jumps, as program flow can get to the instruction
right after unconditional jump instruction only if there is a jump to
that instruction from somewhere else in the program. In such case we'll
mark such instruction as prune/jump point because it's a destination of
a jump.

This change has no changes in terms of number of instructions or states
processes across Cilium and selftests programs.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/r/20221206233345.438540-4-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-06 19:14:38 -08:00
..
preload bpf: iterators: Build and use lightweight bootstrap version of bpftool 2022-07-15 12:01:30 -07:00
arraymap.c bpf: Do btf_record_free outside map_free callback 2022-11-17 19:11:31 -08:00
bloom_filter.c treewide: use get_random_u32() when possible 2022-10-11 17:42:58 -06:00
bpf_cgrp_storage.c bpf: Fix a compilation failure with clang lto build 2022-11-30 17:13:25 -08:00
bpf_inode_storage.c bpf: Fix a compilation failure with clang lto build 2022-11-30 17:13:25 -08:00
bpf_iter.c bpf: Initialize the bpf_run_ctx in bpf_iter_run_prog() 2022-08-18 17:06:13 -07:00
bpf_local_storage.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2022-11-29 13:04:52 -08:00
bpf_lru_list.c
bpf_lru_list.h printk: stop including cache.h from printk.h 2022-05-13 07:20:07 -07:00
bpf_lsm.c bpf: Do not mark certain LSM hook arguments as trusted 2022-12-04 12:59:58 -08:00
bpf_struct_ops_types.h bpf: Add dummy BPF STRUCT_OPS for test purpose 2021-11-01 14:10:00 -07:00
bpf_struct_ops.c bpf: Remove is_valid_bpf_tramp_flags() 2022-07-11 21:04:58 +02:00
bpf_task_storage.c bpf: Fix a compilation failure with clang lto build 2022-11-30 17:13:25 -08:00
btf.c bpf: Do not mark certain LSM hook arguments as trusted 2022-12-04 12:59:58 -08:00
cgroup_iter.c bpf: Pin the start cgroup in cgroup_iter_seq_init() 2022-11-21 17:40:42 +01:00
cgroup.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2022-10-03 17:44:18 -07:00
core.c bpf: Introduce bpf_obj_new 2022-11-17 19:22:14 -08:00
cpumap.c bpf: Expand map key argument of bpf_redirect_map to u64 2022-11-15 09:00:27 -08:00
devmap.c bpf: Expand map key argument of bpf_redirect_map to u64 2022-11-15 09:00:27 -08:00
disasm.c
disasm.h
dispatcher.c bpf: Add explicit cast to 'void *' for __BPF_DISPATCHER_UPDATE() 2022-11-07 16:07:35 -08:00
hashtab.c bpf: Do btf_record_free outside map_free callback 2022-11-17 19:11:31 -08:00
helpers.c bpf: Don't use rcu_users to refcount in task kfuncs 2022-12-06 16:40:16 -08:00
inode.c bpf: Convert bpf_preload.ko to use light skeleton. 2022-02-10 23:31:51 +01:00
Kconfig rcu: Make the TASKS_RCU Kconfig option be selected 2022-04-20 16:52:58 -07:00
link_iter.c bpf: Add bpf_link iterator 2022-05-10 11:20:45 -07:00
local_storage.c bpf: Consolidate spin_lock, timer management into btf_record 2022-11-03 22:19:40 -07:00
lpm_trie.c bpf: Use bpf_map_area_alloc consistently on bpf map creation 2022-08-10 11:50:43 -07:00
Makefile bpf: Implement cgroup storage available to non-cgroup-attached bpf progs 2022-10-25 23:19:19 -07:00
map_in_map.c bpf: Add comments for map BTF matching requirement for bpf_list_head 2022-11-17 19:22:14 -08:00
map_in_map.h
map_iter.c bpf: Introduce MEM_RDONLY flag 2021-12-18 13:27:41 -08:00
memalloc.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2022-10-24 13:44:11 -07:00
mmap_unlock_work.h bpf: Introduce helper bpf_find_vma 2021-11-07 11:54:51 -08:00
net_namespace.c net: Add includes masked by netdevice.h including uapi/bpf.h 2021-12-29 20:03:05 -08:00
offload.c bpf: Use bpf_map_area_alloc consistently on bpf map creation 2022-08-10 11:50:43 -07:00
percpu_freelist.c bpf: Initialize same number of free nodes for each pcpu_freelist 2022-11-11 12:05:14 -08:00
percpu_freelist.h
prog_iter.c
queue_stack_maps.c bpf: Remove unneeded memset in queue_stack_map creation 2022-08-10 11:48:22 -07:00
reuseport_array.c net: Fix suspicious RCU usage in bpf_sk_reuseport_detach() 2022-08-17 16:42:59 -07:00
ringbuf.c bpf: Rename MEM_ALLOC to MEM_RINGBUF 2022-11-14 21:52:45 -08:00
stackmap.c perf/bpf: Always use perf callchains if exist 2022-09-13 15:03:22 +02:00
syscall.c bpf: Add comments for map BTF matching requirement for bpf_list_head 2022-11-17 19:22:14 -08:00
sysfs_btf.c
task_iter.c - Yu Zhao's Multi-Gen LRU patches are here. They've been under test in 2022-10-10 17:53:04 -07:00
tnum.c
trampoline.c bpf: Remove prog->active check for bpf_lsm and bpf_iter 2022-10-25 23:11:46 -07:00
verifier.c bpf: remove unnecessary prune and jump points 2022-12-06 19:14:38 -08:00