summaryrefslogtreecommitdiff
path: root/kernel/bpf/Makefile
diff options
context:
space:
mode:
authorBjörn Töpel <bjorn.topel@intel.com>2019-12-13 18:51:08 +0100
committerAlexei Starovoitov <ast@kernel.org>2019-12-13 13:09:32 -0800
commit75ccbef6369e94ecac696a152a998a978d41376b (patch)
treec1d92822ed470de368dfe5a102af694ffb1ee7e3 /kernel/bpf/Makefile
parent98e8627efcada18ac043a77b9101b4b4c768090b (diff)
bpf: Introduce BPF dispatcher
The BPF dispatcher is a multi-way branch code generator, mainly targeted for XDP programs. When an XDP program is executed via the bpf_prog_run_xdp(), it is invoked via an indirect call. The indirect call has a substantial performance impact, when retpolines are enabled. The dispatcher transform indirect calls to direct calls, and therefore avoids the retpoline. The dispatcher is generated using the BPF JIT, and relies on text poking provided by bpf_arch_text_poke(). The dispatcher hijacks a trampoline function it via the __fentry__ nop of the trampoline. One dispatcher instance currently supports up to 64 dispatch points. A user creates a dispatcher with its corresponding trampoline with the DEFINE_BPF_DISPATCHER macro. Signed-off-by: Björn Töpel <bjorn.topel@intel.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20191213175112.30208-3-bjorn.topel@gmail.com
Diffstat (limited to 'kernel/bpf/Makefile')
-rw-r--r--kernel/bpf/Makefile1
1 files changed, 1 insertions, 0 deletions
diff --git a/kernel/bpf/Makefile b/kernel/bpf/Makefile
index 3f671bf617e8..d4f330351f87 100644
--- a/kernel/bpf/Makefile
+++ b/kernel/bpf/Makefile
@@ -8,6 +8,7 @@ obj-$(CONFIG_BPF_SYSCALL) += local_storage.o queue_stack_maps.o
obj-$(CONFIG_BPF_SYSCALL) += disasm.o
obj-$(CONFIG_BPF_JIT) += trampoline.o
obj-$(CONFIG_BPF_SYSCALL) += btf.o
+obj-$(CONFIG_BPF_JIT) += dispatcher.o
ifeq ($(CONFIG_NET),y)
obj-$(CONFIG_BPF_SYSCALL) += devmap.o
obj-$(CONFIG_BPF_SYSCALL) += cpumap.o