2020-05-06 14:09:28

by Jason Yan

Subject: [PATCH v2] bpf, i386: remove unneeded conversion to bool

The '==' expression itself is bool, no need to convert it to bool again.
This fixes the following coccicheck warning:

arch/x86/net/bpf_jit_comp32.c:1478:50-55: WARNING: conversion to bool
not needed here
arch/x86/net/bpf_jit_comp32.c:1479:50-55: WARNING: conversion to bool
not needed here

Signed-off-by: Jason Yan <[email protected]>
---
v2: change the name 'x32' to 'i386'.

arch/x86/net/bpf_jit_comp32.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/net/bpf_jit_comp32.c b/arch/x86/net/bpf_jit_comp32.c
index 66cd150b7e54..96fde03aa987 100644
--- a/arch/x86/net/bpf_jit_comp32.c
+++ b/arch/x86/net/bpf_jit_comp32.c
@@ -1475,8 +1475,8 @@ static int do_jit(struct bpf_prog *bpf_prog, int *addrs, u8 *image,
for (i = 0; i < insn_cnt; i++, insn++) {
const s32 imm32 = insn->imm;
const bool is64 = BPF_CLASS(insn->code) == BPF_ALU64;
- const bool dstk = insn->dst_reg == BPF_REG_AX ? false : true;
- const bool sstk = insn->src_reg == BPF_REG_AX ? false : true;
+ const bool dstk = insn->dst_reg != BPF_REG_AX;
+ const bool sstk = insn->src_reg != BPF_REG_AX;
const u8 code = insn->code;
const u8 *dst = bpf2ia32[insn->dst_reg];
const u8 *src = bpf2ia32[insn->src_reg];
--
2.21.1

2020-05-06 14:19:32

by H. Peter Anvin

Subject: Re: [PATCH v2] bpf, i386: remove unneeded conversion to bool

On May 6, 2020 7:03:52 AM PDT, Jason Yan <[email protected]> wrote:
>The '==' expression itself is bool, no need to convert it to bool
>again.
>This fixes the following coccicheck warning:
>
>arch/x86/net/bpf_jit_comp32.c:1478:50-55: WARNING: conversion to bool
>not needed here
>arch/x86/net/bpf_jit_comp32.c:1479:50-55: WARNING: conversion to bool
>not needed here
>
>Signed-off-by: Jason Yan <[email protected]>
>---
> v2: change the name 'x32' to 'i386'.
>
> arch/x86/net/bpf_jit_comp32.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
>diff --git a/arch/x86/net/bpf_jit_comp32.c
>b/arch/x86/net/bpf_jit_comp32.c
>index 66cd150b7e54..96fde03aa987 100644
>--- a/arch/x86/net/bpf_jit_comp32.c
>+++ b/arch/x86/net/bpf_jit_comp32.c
>@@ -1475,8 +1475,8 @@ static int do_jit(struct bpf_prog *bpf_prog, int
>*addrs, u8 *image,
> for (i = 0; i < insn_cnt; i++, insn++) {
> const s32 imm32 = insn->imm;
> const bool is64 = BPF_CLASS(insn->code) == BPF_ALU64;
>- const bool dstk = insn->dst_reg == BPF_REG_AX ? false : true;
>- const bool sstk = insn->src_reg == BPF_REG_AX ? false : true;
>+ const bool dstk = insn->dst_reg != BPF_REG_AX;
>+ const bool sstk = insn->src_reg != BPF_REG_AX;
> const u8 code = insn->code;
> const u8 *dst = bpf2ia32[insn->dst_reg];
> const u8 *src = bpf2ia32[insn->src_reg];

"foo ? true : false" is also far better written !!foo when it isn't totally redundant.
--
Sent from my Android device with K-9 Mail. Please excuse my brevity.

2020-05-06 22:10:40

by Martin KaFai Lau

Subject: Re: [PATCH v2] bpf, i386: remove unneeded conversion to bool

On Wed, May 06, 2020 at 10:03:52PM +0800, Jason Yan wrote:
> The '==' expression itself is bool, no need to convert it to bool again.
> This fixes the following coccicheck warning:
Make sense.

It may belong to bpf-next instead.

Acked-by: Martin KaFai Lau <[email protected]>

2020-05-07 16:02:59

by Daniel Borkmann

Subject: Re: [PATCH v2] bpf, i386: remove unneeded conversion to bool

On 5/7/20 12:04 AM, Martin KaFai Lau wrote:
> On Wed, May 06, 2020 at 10:03:52PM +0800, Jason Yan wrote:
>> The '==' expression itself is bool, no need to convert it to bool again.
>> This fixes the following coccicheck warning:
> Make sense.
>
> It may belong to bpf-next instead.
>
> Acked-by: Martin KaFai Lau <[email protected]>

Applied, thanks!