[PATCH powerpc/next 04/17] powerpc64/bpf: Do not save/restore LR on each call to bpf_stf_barrier()
From: Naveen N. Rao <hidden>
Date: 2022-02-14 11:13:31
Also in:
bpf
Subsystem:
bpf jit for powerpc (32-bit and 64-bit), bpf [general] (safe dynamic programs and tools), linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Hari Bathini, Christophe Leroy, Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, Madhavan Srinivasan, Linus Torvalds
Instead of saving and restoring LR before each invocation to bpf_stf_barrier(), set SEEN_FUNC flag so that we save/restore LR in prologue/epilogue. Signed-off-by: Naveen N. Rao <redacted> --- arch/powerpc/net/bpf_jit_comp64.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/arch/powerpc/net/bpf_jit_comp64.c b/arch/powerpc/net/bpf_jit_comp64.c
index 371bd5a16859c7..27ac2fc7670298 100644
--- a/arch/powerpc/net/bpf_jit_comp64.c
+++ b/arch/powerpc/net/bpf_jit_comp64.c@@ -690,11 +690,10 @@ int bpf_jit_build_body(struct bpf_prog *fp, u32 *image, struct codegen_context * EMIT(PPC_RAW_ORI(_R31, _R31, 0)); break; case STF_BARRIER_FALLBACK: - EMIT(PPC_RAW_MFLR(b2p[TMP_REG_1])); + ctx->seen |= SEEN_FUNC; PPC_LI64(12, dereference_kernel_function_descriptor(bpf_stf_barrier)); EMIT(PPC_RAW_MTCTR(12)); EMIT(PPC_RAW_BCTRL()); - EMIT(PPC_RAW_MTLR(b2p[TMP_REG_1])); break; case STF_BARRIER_NONE: break;
--
2.35.1