kernel/linux.git/include/linux/indirect_call_wrapper.h, branch v6.6.132

indirect_call_wrapper: do not reevaluate function pointer

2026-03-25T10:05:40+00:00

[ Upstream commit 710f5c76580306cdb9ec51fac8fcf6a8faff7821 ] We have an increasing number of READ_ONCE(xxx->function) combined with INDIRECT_CALL_[1234]() helpers. Unfortunately this forces INDIRECT_CALL_[1234]() to read xxx->function many times, which is not what we wanted. Fix these macros so that xxx->function value is not reloaded. $ scripts/bloat-o-meter -t vmlinux.0 vmlinux add/remove: 0/0 grow/shrink: 1/65 up/down: 122/-1084 (-962) Function old new delta ip_push_pending_frames 59 181 +122 ip6_finish_output 687 681 -6 __udp_enqueue_schedule_skb 1078 1072 -6 ioam6_output 2319 2312 -7 xfrm4_rcv_encap_finish2 64 56 -8 xfrm4_output 297 289 -8 vrf_ip_local_out 278 270 -8 vrf_ip6_local_out 278 270 -8 seg6_input_finish 64 56 -8 rpl_output 700 692 -8 ipmr_forward_finish 124 116 -8 ip_forward_finish 143 135 -8 ip6mr_forward2_finish 100 92 -8 ip6_forward_finish 73 65 -8 input_action_end_bpf 1091 1083 -8 dst_input 52 44 -8 __xfrm6_output 801 793 -8 __xfrm4_output 83 75 -8 bpf_input 500 491 -9 __tcp_check_space 530 521 -9 input_action_end_dt6 291 280 -11 vti6_tnl_xmit 1634 1622 -12 bpf_xmit 1203 1191 -12 rpl_input 497 483 -14 rawv6_send_hdrinc 1355 1341 -14 ndisc_send_skb 1030 1016 -14 ipv6_srh_rcv 1377 1363 -14 ip_send_unicast_reply 1253 1239 -14 ip_rcv_finish 226 212 -14 ip6_rcv_finish 300 286 -14 input_action_end_x_core 205 191 -14 input_action_end_x 355 341 -14 input_action_end_t 205 191 -14 input_action_end_dx6_finish 127 113 -14 input_action_end_dx4_finish 373 359 -14 input_action_end_dt4 426 412 -14 input_action_end_core 186 172 -14 input_action_end_b6_encap 292 278 -14 input_action_end_b6 198 184 -14 igmp6_send 1332 1318 -14 ip_sublist_rcv 864 848 -16 ip6_sublist_rcv 1091 1075 -16 ipv6_rpl_srh_rcv 1937 1920 -17 xfrm_policy_queue_process 1246 1228 -18 seg6_output_core 903 885 -18 mld_sendpack 856 836 -20 NF_HOOK 756 736 -20 vti_tunnel_xmit 1447 1426 -21 input_action_end_dx6 664 642 -22 input_action_end 1502 1480 -22 sock_sendmsg_nosec 134 111 -23 ip6mr_forward2 388 364 -24 sock_recvmsg_nosec 134 109 -25 seg6_input_core 836 810 -26 ip_send_skb 172 146 -26 ip_local_out 140 114 -26 ip6_local_out 140 114 -26 __sock_sendmsg 162 136 -26 __ip_queue_xmit 1196 1170 -26 __ip_finish_output 405 379 -26 ipmr_queue_fwd_xmit 373 346 -27 sock_recvmsg 173 145 -28 ip6_xmit 1635 1607 -28 xfrm_output_resume 1418 1389 -29 ip_build_and_send_pkt 625 591 -34 dst_output 504 432 -72 Total: Before=25217686, After=25216724, chg -0.00% Fixes: 283c16a2dfd3 ("indirect call wrappers: helpers to speed-up indirect calls of builtin") Signed-off-by: Eric Dumazet Reviewed-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20260227172603.1700433-1-edumazet@google.com Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin

Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

2021-02-16T21:14:06+00:00

Daniel Borkmann says: ==================== pull-request: bpf-next 2021-02-16 The following pull-request contains BPF updates for your *net-next* tree. There's a small merge conflict between 7eeba1706eba ("tcp: Add receive timestamp support for receive zerocopy.") from net-next tree and 9cacf81f8161 ("bpf: Remove extra lock_sock for TCP_ZEROCOPY_RECEIVE") from bpf-next tree. Resolve as follows: [...] lock_sock(sk); err = tcp_zerocopy_receive(sk, &zc, &tss); err = BPF_CGROUP_RUN_PROG_GETSOCKOPT_KERN(sk, level, optname, &zc, &len, err); release_sock(sk); [...] We've added 116 non-merge commits during the last 27 day(s) which contain a total of 156 files changed, 5662 insertions(+), 1489 deletions(-). The main changes are: 1) Adds support of pointers to types with known size among global function args to overcome the limit on max # of allowed args, from Dmitrii Banshchikov. 2) Add bpf_iter for task_vma which can be used to generate information similar to /proc/pid/maps, from Song Liu. 3) Enable bpf_{g,s}etsockopt() from all sock_addr related program hooks. Allow rewriting bind user ports from BPF side below the ip_unprivileged_port_start range, both from Stanislav Fomichev. 4) Prevent recursion on fentry/fexit & sleepable programs and allow map-in-map as well as per-cpu maps for the latter, from Alexei Starovoitov. 5) Add selftest script to run BPF CI locally. Also enable BPF ringbuffer for sleepable programs, both from KP Singh. 6) Extend verifier to enable variable offset read/write access to the BPF program stack, from Andrei Matei. 7) Improve tc & XDP MTU handling and add a new bpf_check_mtu() helper to query device MTU from programs, from Jesper Dangaard Brouer. 8) Allow bpf_get_socket_cookie() helper also be called from [sleepable] BPF tracing programs, from Florent Revest. 9) Extend x86 JIT to pad JMPs with NOPs for helping image to converge when otherwise too many passes are required, from Gary Lin. 10) Verifier fixes on atomics with BPF_FETCH as well as function-by-function verification both related to zero-extension handling, from Ilya Leoshkevich. 11) Better kernel build integration of resolve_btfids tool, from Jiri Olsa. 12) Batch of AF_XDP selftest cleanups and small performance improvement for libbpf's xsk map redirect for newer kernels, from Björn Töpel. 13) Follow-up BPF doc and verifier improvements around atomics with BPF_FETCH, from Brendan Jackman. 14) Permit zero-sized data sections e.g. if ELF .rodata section contains read-only data from local variables, from Yonghong Song. 15) veth driver skb bulk-allocation for ndo_xdp_xmit, from Lorenzo Bianconi. ==================== Signed-off-by: David S. Miller

net: add EXPORT_INDIRECT_CALLABLE wrapper

2021-02-05T02:06:26+00:00

When a static function is annotated with INDIRECT_CALLABLE_SCOPE and CONFIG_RETPOLINE is set, the static keyword is removed. Sometimes the function needs to be exported but EXPORT_SYMBOL can't be used because if CONFIG_RETPOLINE is not set, we will attempt to export a static symbol. This patch introduces a new indirect call wrapper: EXPORT_INDIRECT_CALLABLE. This basically does EXPORT_SYMBOL when CONFIG_RETPOLINE is set, but does nothing when it's not. Reported-by: Stephen Rothwell Signed-off-by: Brian Vazquez Link: https://lore.kernel.org/r/20210204181839.558951-1-brianvv@google.com Signed-off-by: Jakub Kicinski

bpf: Remove extra lock_sock for TCP_ZEROCOPY_RECEIVE

2021-01-20T22:23:00+00:00

Add custom implementation of getsockopt hook for TCP_ZEROCOPY_RECEIVE. We skip generic hooks for TCP_ZEROCOPY_RECEIVE and have a custom call in do_tcp_getsockopt using the on-stack data. This removes 3% overhead for locking/unlocking the socket. Without this patch: 3.38% 0.07% tcp_mmap [kernel.kallsyms] [k] __cgroup_bpf_run_filter_getsockopt | --3.30%--__cgroup_bpf_run_filter_getsockopt | --0.81%--__kmalloc With the patch applied: 0.52% 0.12% tcp_mmap [kernel.kallsyms] [k] __cgroup_bpf_run_filter_getsockopt_kern Note, exporting uapi/tcp.h requires removing netinet/tcp.h from test_progs.h because those headers have confliciting definitions. Signed-off-by: Stanislav Fomichev Signed-off-by: Alexei Starovoitov Acked-by: Martin KaFai Lau Link: https://lore.kernel.org/bpf/20210115163501.805133-2-sdf@google.com

indirect_call_wrapper: extend indirect wrapper to support up to 4 calls

2020-06-23T22:11:19+00:00

There are many places where 2 annotations are not enough. This patch adds INDIRECT_CALL_3 and INDIRECT_CALL_4 to cover such cases. Signed-off-by: Brian Vazquez Acked-by: Paolo Abeni Signed-off-by: David S. Miller

net: unbreak CONFIG_RETPOLINE=n builds

2018-12-17T17:19:49+00:00

The kbuild bot reported a build breakage with CONFIG_RETPOLINE=n due to commit aaa5d90b395a ("net: use indirect call wrappers at GRO network layer"). I screwed the wrapper implementation for such config. Fix the issue properly ignoring the builtin symbols arguments, when retpoline is not enabled. Reported-by: kbuild test robot Fixes: aaa5d90b395a ("net: use indirect call wrappers at GRO network layer") Signed-off-by: Paolo Abeni Signed-off-by: David S. Miller

indirect call wrappers: helpers to speed-up indirect calls of builtin

2018-12-15T21:23:02+00:00

This header define a bunch of helpers that allow avoiding the retpoline overhead when calling builtin functions via function pointers. It boils down to explicitly comparing the function pointers to known builtin functions and eventually invoke directly the latter. The macros defined here implement the boilerplate for the above schema and will be used by the next patches. rfc -> v1: - use branch prediction hint, as suggested by Eric v1 -> v2: - list explicitly the builtin function names in INDIRECT_CALL_*(), as suggested by Ed Cree Suggested-by: Eric Dumazet Signed-off-by: Paolo Abeni Signed-off-by: David S. Miller