Commit 3cb70413 authored by Pu Lehui's avatar Pu Lehui Committed by Andrii Nakryiko
Browse files

bpf, riscv: Support riscv jit to provide bpf_line_info 



Add support for riscv jit to provide bpf_line_info. We need to
consider the prologue offset in ctx->offset, but unlike x86 and
arm64, ctx->offset of riscv does not provide an extra slot for
the prologue, so here we just calculate the len of prologue and
add it to ctx->offset at the end. Both RV64 and RV32 have been
tested.

Signed-off-by: default avatarPu Lehui <pulehui@huawei.com>
Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: default avatarAndrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220530092815.1112406-3-pulehui@huawei.com
parent 2cd00852

arch/riscv/net/bpf_jit.h

+1 −0
Original line number Diff line number Diff line
@@ -69,6 +69,7 @@ struct rv_jit_context { 
	struct bpf_prog *prog;

	u16 *insns;		/* RV insns */

	int ninsns;

	int body_len;

	int epilogue_offset;

	int *offset;		/* BPF to RV */

	int nexentries;

arch/riscv/net/bpf_jit_core.c

+7 −1
Original line number Diff line number Diff line
@@ -44,7 +44,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog) 
	unsigned int prog_size = 0, extable_size = 0;

	bool tmp_blinded = false, extra_pass = false;

	struct bpf_prog *tmp, *orig_prog = prog;

	int pass = 0, prev_ninsns = 0, i;

	int pass = 0, prev_ninsns = 0, prologue_len, i;

	struct rv_jit_data *jit_data;

	struct rv_jit_context *ctx;
@@ -95,6 +95,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog) 
			prog = orig_prog;

			goto out_offset;

		}

		ctx->body_len = ctx->ninsns;

		bpf_jit_build_prologue(ctx);

		ctx->epilogue_offset = ctx->ninsns;

		bpf_jit_build_epilogue(ctx);
@@ -161,6 +162,11 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog) 


	if (!prog->is_func || extra_pass) {

		bpf_jit_binary_lock_ro(jit_data->header);

		prologue_len = ctx->epilogue_offset - ctx->body_len;

		for (i = 0; i < prog->len; i++)

			ctx->offset[i] = ninsns_rvoff(prologue_len +

						      ctx->offset[i]);

		bpf_prog_fill_jited_linfo(prog, ctx->offset);

out_offset:

		kfree(ctx->offset);

		kfree(jit_data);