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: Pu Lehui <pulehui@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220530092815.1112406-3-pulehui@huawei.com
This commit is contained in:
Pu Lehui 2022-05-30 17:28:11 +08:00 committed by Andrii Nakryiko
parent 2cd0085227
commit 3cb7041304
2 changed files with 8 additions and 1 deletions

View File

@ -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;

View File

@ -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);