From: "Björn Töpel" <bjorn.topel@gmail.com>
To: daniel@iogearbox.net, ast@kernel.org, netdev@vger.kernel.org
Cc: "Björn Töpel" <bjorn.topel@gmail.com>,
linux-riscv@lists.infradead.org, bpf@vger.kernel.org
Subject: [PATCH bpf-next v2 3/9] riscv, bpf: add support for far branching when emitting tail call
Date: Mon, 16 Dec 2019 10:13:37 +0100
Message-ID: <20191216091343.23260-4-bjorn.topel@gmail.com> (raw)
In-Reply-To: <20191216091343.23260-1-bjorn.topel@gmail.com>
Start use the emit_branch() function in the tail call emitter in order
to support far branching.
Signed-off-by: Björn Töpel <bjorn.topel@gmail.com>
---
arch/riscv/net/bpf_jit_comp.c | 22 +++-------------------
1 file changed, 3 insertions(+), 19 deletions(-)
diff --git a/arch/riscv/net/bpf_jit_comp.c b/arch/riscv/net/bpf_jit_comp.c
index e599458a9bcd..c38c95df3440 100644
--- a/arch/riscv/net/bpf_jit_comp.c
+++ b/arch/riscv/net/bpf_jit_comp.c
@@ -496,16 +496,6 @@ static int is_12b_check(int off, int insn)
return 0;
}
-static int is_13b_check(int off, int insn)
-{
- if (!is_13b_int(off)) {
- pr_err("bpf-jit: insn=%d 13b < offset=%d not supported yet!\n",
- insn, (int)off);
- return -1;
- }
- return 0;
-}
-
static int is_21b_check(int off, int insn)
{
if (!is_21b_int(off)) {
@@ -744,18 +734,14 @@ static int emit_bpf_tail_call(int insn, struct rv_jit_context *ctx)
return -1;
emit(rv_lwu(RV_REG_T1, off, RV_REG_A1), ctx);
off = (tc_ninsn - (ctx->ninsns - start_insn)) << 2;
- if (is_13b_check(off, insn))
- return -1;
- emit(rv_bgeu(RV_REG_A2, RV_REG_T1, off >> 1), ctx);
+ emit_branch(BPF_JGE, RV_REG_A2, RV_REG_T1, off, ctx);
/* if (--TCC < 0)
* goto out;
*/
emit(rv_addi(RV_REG_T1, tcc, -1), ctx);
off = (tc_ninsn - (ctx->ninsns - start_insn)) << 2;
- if (is_13b_check(off, insn))
- return -1;
- emit(rv_blt(RV_REG_T1, RV_REG_ZERO, off >> 1), ctx);
+ emit_branch(BPF_JSLT, RV_REG_T1, RV_REG_ZERO, off, ctx);
/* prog = array->ptrs[index];
* if (!prog)
@@ -768,9 +754,7 @@ static int emit_bpf_tail_call(int insn, struct rv_jit_context *ctx)
return -1;
emit(rv_ld(RV_REG_T2, off, RV_REG_T2), ctx);
off = (tc_ninsn - (ctx->ninsns - start_insn)) << 2;
- if (is_13b_check(off, insn))
- return -1;
- emit(rv_beq(RV_REG_T2, RV_REG_ZERO, off >> 1), ctx);
+ emit_branch(BPF_JEQ, RV_REG_T2, RV_REG_ZERO, off, ctx);
/* goto *(prog->bpf_func + 4); */
off = offsetof(struct bpf_prog, bpf_func);
--
2.20.1
next prev parent reply index
Thread overview: 33+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-12-16 9:13 [PATCH bpf-next v2 0/9] riscv: BPF JIT fix, optimizations and far jumps support Björn Töpel
2019-12-16 9:13 ` [PATCH bpf-next v2 1/9] riscv, bpf: fix broken BPF tail calls Björn Töpel
2019-12-16 9:13 ` [PATCH bpf-next v2 2/9] riscv, bpf: add support for far branching Björn Töpel
2019-12-16 9:13 ` Björn Töpel [this message]
2019-12-16 9:13 ` [PATCH bpf-next v2 4/9] riscv, bpf: add support for far jumps and exits Björn Töpel
2019-12-16 9:13 ` [PATCH bpf-next v2 5/9] riscv, bpf: optimize BPF tail calls Björn Töpel
2019-12-16 9:13 ` [PATCH bpf-next v2 6/9] riscv, bpf: provide RISC-V specific JIT image alloc/free Björn Töpel
2019-12-16 15:09 ` Daniel Borkmann
2019-12-18 6:23 ` Björn Töpel
2020-01-04 1:32 ` Paul Walmsley
2020-01-07 10:24 ` Björn Töpel
2020-01-07 10:47 ` Paul Walmsley
2020-02-02 13:37 ` Alex Ghiti
2020-02-03 12:28 ` Björn Töpel
2020-02-03 20:57 ` Alex Ghiti
2019-12-16 9:13 ` [PATCH bpf-next v2 7/9] riscv, bpf: optimize calls Björn Töpel
2019-12-16 9:13 ` [PATCH bpf-next v2 8/9] riscv, bpf: add missing uapi header for BPF_PROG_TYPE_PERF_EVENT programs Björn Töpel
2019-12-16 9:13 ` [PATCH bpf-next v2 9/9] riscv, perf: add arch specific perf_arch_bpf_user_pt_regs Björn Töpel
2019-12-19 15:07 ` [PATCH bpf-next v2 0/9] riscv: BPF JIT fix, optimizations and far jumps support Daniel Borkmann
2019-12-19 22:02 ` [PATCH bpf-next v2 1/9] riscv, bpf: fix broken BPF tail calls Palmer Dabbelt
2019-12-23 18:03 ` [PATCH bpf-next v2 2/9] riscv, bpf: add support for far branching Palmer Dabbelt
2020-01-07 8:13 ` Björn Töpel
2020-01-23 2:08 ` Palmer Dabbelt
2019-12-23 18:18 ` [PATCH bpf-next v2 3/9] riscv, bpf: add support for far branching when emitting tail call Palmer Dabbelt
2019-12-23 18:18 ` [PATCH bpf-next v2 4/9] riscv, bpf: add support for far jumps and exits Palmer Dabbelt
2019-12-23 18:29 ` [PATCH bpf-next v2 5/9] riscv, bpf: optimize BPF tail calls Palmer Dabbelt
2019-12-23 18:30 ` [PATCH bpf-next v2 6/9] riscv, bpf: provide RISC-V specific JIT image alloc/free Palmer Dabbelt
2019-12-23 18:58 ` [PATCH bpf-next v2 7/9] riscv, bpf: optimize calls Palmer Dabbelt
2020-01-07 10:14 ` Björn Töpel
2020-01-28 2:15 ` Palmer Dabbelt
2020-02-03 12:11 ` Björn Töpel
2019-12-23 18:58 ` [PATCH bpf-next v2 8/9] riscv, bpf: add missing uapi header for BPF_PROG_TYPE_PERF_EVENT programs Palmer Dabbelt
2019-12-23 18:58 ` [PATCH bpf-next v2 9/9] riscv, perf: add arch specific perf_arch_bpf_user_pt_regs Palmer Dabbelt
Reply instructions:
You may reply publically to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20191216091343.23260-4-bjorn.topel@gmail.com \
--to=bjorn.topel@gmail.com \
--cc=ast@kernel.org \
--cc=bpf@vger.kernel.org \
--cc=daniel@iogearbox.net \
--cc=linux-riscv@lists.infradead.org \
--cc=netdev@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Linux-RISC-V Archive on lore.kernel.org
Archives are clonable:
git clone --mirror https://lore.kernel.org/linux-riscv/0 linux-riscv/git/0.git
# If you have public-inbox 1.1+ installed, you may
# initialize and index your mirror using the following commands:
public-inbox-init -V2 linux-riscv linux-riscv/ https://lore.kernel.org/linux-riscv \
linux-riscv@lists.infradead.org
public-inbox-index linux-riscv
Example config snippet for mirrors
Newsgroup available over NNTP:
nntp://nntp.lore.kernel.org/org.infradead.lists.linux-riscv
AGPL code for this site: git clone https://public-inbox.org/public-inbox.git