bpf: Remove the unnecessary insn buffer comparison

[PATCH bpf-next v1] bpf: Remove the unnecessary insn buffer comparison

Posted by Haiyue Wang 3 years ago

The variable 'insn' is initialized to 'insn_buf' without being changed,
only some helper macros are defined, so the insn buffer comparison is
unnecessary, just remove it.

Signed-off-by: Haiyue Wang <haiyue.wang@intel.com>
---
 net/core/filter.c | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/net/core/filter.c b/net/core/filter.c
index ab811293ae5d..d9befa6ba04e 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -6847,9 +6847,6 @@ u32 bpf_tcp_sock_convert_ctx_access(enum bpf_access_type type,
 					FIELD));			\
 	} while (0)
 
-	if (insn > insn_buf)
-		return insn - insn_buf;
-
 	switch (si->off) {
 	case offsetof(struct bpf_tcp_sock, rtt_min):
 		BUILD_BUG_ON(sizeof_field(struct tcp_sock, rtt_min) !=
@@ -10147,9 +10144,6 @@ static u32 sock_ops_convert_ctx_access(enum bpf_access_type type,
 			SOCK_OPS_GET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ);	      \
 	} while (0)
 
-	if (insn > insn_buf)
-		return insn - insn_buf;
-
 	switch (si->off) {
 	case offsetof(struct bpf_sock_ops, op):
 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_sock_ops_kern,
-- 
2.39.0

Re: [PATCH bpf-next v1] bpf: Remove the unnecessary insn buffer comparison

Posted by patchwork-bot+netdevbpf@kernel.org 3 years ago

Hello:

This patch was applied to bpf/bpf-next.git (master)
by Daniel Borkmann <daniel@iogearbox.net>:

On Sun,  8 Jan 2023 23:12:57 +0800 you wrote:
> The variable 'insn' is initialized to 'insn_buf' without being changed,
> only some helper macros are defined, so the insn buffer comparison is
> unnecessary, just remove it.
> 
> Signed-off-by: Haiyue Wang <haiyue.wang@intel.com>
> ---
>  net/core/filter.c | 6 ------
>  1 file changed, 6 deletions(-)

Here is the summary with links:
  - [bpf-next,v1] bpf: Remove the unnecessary insn buffer comparison
    https://git.kernel.org/bpf/bpf-next/c/66cf99b55e58

You are awesome, thank you!
-- 
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html

Re: [PATCH bpf-next v1] bpf: Remove the unnecessary insn buffer comparison

Posted by sdf@google.com 3 years ago

On 01/08, Haiyue Wang wrote:
> The variable 'insn' is initialized to 'insn_buf' without being changed,
> only some helper macros are defined, so the insn buffer comparison is
> unnecessary, just remove it.

> Signed-off-by: Haiyue Wang <haiyue.wang@intel.com>

Acked-by: Stanislav Fomichev <sdf@google.com>

Looks like these should have been removed as part of commit 2377b81de527
("bpf: split shared bpf_tcp_sock and bpf_sock_ops implementation").

> ---
>   net/core/filter.c | 6 ------
>   1 file changed, 6 deletions(-)

> diff --git a/net/core/filter.c b/net/core/filter.c
> index ab811293ae5d..d9befa6ba04e 100644
> --- a/net/core/filter.c
> +++ b/net/core/filter.c
> @@ -6847,9 +6847,6 @@ u32 bpf_tcp_sock_convert_ctx_access(enum  
> bpf_access_type type,
>   					FIELD));			\
>   	} while (0)

> -	if (insn > insn_buf)
> -		return insn - insn_buf;
> -
>   	switch (si->off) {
>   	case offsetof(struct bpf_tcp_sock, rtt_min):
>   		BUILD_BUG_ON(sizeof_field(struct tcp_sock, rtt_min) !=
> @@ -10147,9 +10144,6 @@ static u32 sock_ops_convert_ctx_access(enum  
> bpf_access_type type,
>   			SOCK_OPS_GET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ);	      \
>   	} while (0)

> -	if (insn > insn_buf)
> -		return insn - insn_buf;
> -
>   	switch (si->off) {
>   	case offsetof(struct bpf_sock_ops, op):
>   		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_sock_ops_kern,
> --
> 2.39.0

RE: [PATCH bpf-next v1] bpf: Remove the unnecessary insn buffer comparison

Posted by Wang, Haiyue 3 years ago

> -----Original Message-----
> From: sdf@google.com <sdf@google.com>
> Sent: Tuesday, January 10, 2023 01:39
> To: Wang, Haiyue <haiyue.wang@intel.com>
> Cc: bpf@vger.kernel.org; Alexei Starovoitov <ast@kernel.org>; Daniel Borkmann <daniel@iogearbox.net>;
> Andrii Nakryiko <andrii@kernel.org>; Martin KaFai Lau <martin.lau@linux.dev>; Song Liu
> <song@kernel.org>; Yonghong Song <yhs@fb.com>; John Fastabend <john.fastabend@gmail.com>; KP Singh
> <kpsingh@kernel.org>; Hao Luo <haoluo@google.com>; Jiri Olsa <jolsa@kernel.org>; David S. Miller
> <davem@davemloft.net>; Eric Dumazet <edumazet@google.com>; Jakub Kicinski <kuba@kernel.org>; Paolo
> Abeni <pabeni@redhat.com>; netdev@vger.kernel.org; linux-kernel@vger.kernel.org
> Subject: Re: [PATCH bpf-next v1] bpf: Remove the unnecessary insn buffer comparison
> 
> On 01/08, Haiyue Wang wrote:
> > The variable 'insn' is initialized to 'insn_buf' without being changed,
> > only some helper macros are defined, so the insn buffer comparison is
> > unnecessary, just remove it.
> 
> > Signed-off-by: Haiyue Wang <haiyue.wang@intel.com>
> 
> Acked-by: Stanislav Fomichev <sdf@google.com>
> 
> Looks like these should have been removed as part of commit 2377b81de527
> ("bpf: split shared bpf_tcp_sock and bpf_sock_ops implementation").
> 

Thanks for the information, yes, it was missed. ;-)

> > ---
> >   net/core/filter.c | 6 ------
> >   1 file changed, 6 deletions(-)
> 


> > --
> > 2.39.0