[PATCH net-next 0/3] Misc BPF cleanup

[PATCH net-next 0/3] Misc BPF cleanup

[Alexander Alemayhu]

Hei,

while looking into making the Makefile in samples/bpf better handle O= I saw
several warnings when running `make clean && make samples/bpf/`. This series
reduces those warnings.

Thanks.

Alexander Alemayhu (3):
  samples/bpf: add -Wno-unknown-warning-option to clang
  samples/bpf: add static to function with no prototype
  samples/bpf: check before defining offsetof

 samples/bpf/Makefile                    | 1 +
 samples/bpf/cookie_uid_helper_example.c | 2 +-
 samples/bpf/test_lru_dist.c             | 4 +++-
 3 files changed, 5 insertions(+), 2 deletions(-)

-- 
2.9.3

[PATCH net-next 1/3] samples/bpf: add -Wno-unknown-warning-option to clang

[Alexander Alemayhu]

I was initially going to remove '-Wno-address-of-packed-member' because I
thought it was not supposed to be there but Daniel suggested using
'-Wno-unknown-warning-option'. 

This silences several warnings similiar to the one below

warning: unknown warning option '-Wno-address-of-packed-member' [-Wunknown-warning-option]
1 warning generated.
clang  -nostdinc -isystem /usr/lib/gcc/x86_64-redhat-linux/6.3.1/include -I./arch/x86/include -I./arch/x86/include/generated/uapi -I./arch/x86/include/generated  -I./include
 -I./arch/x86/include/uapi -I./include/uapi -I./include/generated/uapi -include ./include/linux/kconfig.h  \
        -D__KERNEL__ -D__ASM_SYSREG_H -Wno-unused-value -Wno-pointer-sign \
        -Wno-compare-distinct-pointer-types \
        -Wno-gnu-variable-sized-type-not-at-end \
        -Wno-address-of-packed-member -Wno-tautological-compare \
        -O2 -emit-llvm -c samples/bpf/xdp_tx_iptunnel_kern.c -o -| llc -march=bpf -filetype=obj -o samples/bpf/xdp_tx_iptunnel_kern.o

$ clang --version

 clang version 3.9.1 (tags/RELEASE_391/final)
 Target: x86_64-unknown-linux-gnu
 Thread model: posix
 InstalledDir: /usr/bin

Signed-off-by: Alexander Alemayhu <alexander@alemayhu.com>
---
 samples/bpf/Makefile | 1 +
 1 file changed, 1 insertion(+)

diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile
index d42b495b0992..6c7468eb3684 100644
--- a/samples/bpf/Makefile
+++ b/samples/bpf/Makefile
@@ -189,4 +189,5 @@ $(obj)/%.o: $(src)/%.c
 		-Wno-compare-distinct-pointer-types \
 		-Wno-gnu-variable-sized-type-not-at-end \
 		-Wno-address-of-packed-member -Wno-tautological-compare \
+		-Wno-unknown-warning-option \
 		-O2 -emit-llvm -c $< -o -| $(LLC) -march=bpf -filetype=obj -o $@
-- 
2.9.3

[PATCH net-next 2/3] samples/bpf: add static to function with no prototype

[Alexander Alemayhu]

Fixes the following warning

samples/bpf/cookie_uid_helper_example.c: At top level:
samples/bpf/cookie_uid_helper_example.c:276:6: warning: no previous prototype for ‘finish’ [-Wmissing-prototypes]
 void finish(int ret)
      ^~~~~~
  HOSTLD  samples/bpf/per_socket_stats_example

Signed-off-by: Alexander Alemayhu <alexander@alemayhu.com>
---
 samples/bpf/cookie_uid_helper_example.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/samples/bpf/cookie_uid_helper_example.c b/samples/bpf/cookie_uid_helper_example.c
index ad5afedf2e70..9ce55840d61d 100644
--- a/samples/bpf/cookie_uid_helper_example.c
+++ b/samples/bpf/cookie_uid_helper_example.c
@@ -273,7 +273,7 @@ static int usage(void)
 	return 1;
 }
 
-void finish(int ret)
+static void finish(int ret)
 {
 	test_finish = true;
 }
-- 
2.9.3

[PATCH net-next 3/3] samples/bpf: check before defining offsetof

[Alexander Alemayhu]

Fixes the following warning

samples/bpf/test_lru_dist.c:28:0: warning: "offsetof" redefined
 #define offsetof(TYPE, MEMBER) ((size_t)&((TYPE *)0)->MEMBER)

In file included from ./tools/lib/bpf/bpf.h:25:0,
                 from samples/bpf/libbpf.h:5,
                 from samples/bpf/test_lru_dist.c:24:
/usr/lib/gcc/x86_64-redhat-linux/6.3.1/include/stddef.h:417:0: note: this is the location of the previous definition
 #define offsetof(TYPE, MEMBER) __builtin_offsetof (TYPE, MEMBER)

Signed-off-by: Alexander Alemayhu <alexander@alemayhu.com>
---
 samples/bpf/test_lru_dist.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/samples/bpf/test_lru_dist.c b/samples/bpf/test_lru_dist.c
index d96dc88d3b04..73c357142268 100644
--- a/samples/bpf/test_lru_dist.c
+++ b/samples/bpf/test_lru_dist.c
@@ -25,7 +25,9 @@
 #include "bpf_util.h"
 
 #define min(a, b) ((a) < (b) ? (a) : (b))
-#define offsetof(TYPE, MEMBER)	((size_t)&((TYPE *)0)->MEMBER)
+#ifndef offsetof
+# define offsetof(TYPE, MEMBER)	((size_t)&((TYPE *)0)->MEMBER)
+#endif
 #define container_of(ptr, type, member) ({			\
 	const typeof( ((type *)0)->member ) *__mptr = (ptr);	\
 	(type *)( (char *)__mptr - offsetof(type,member) );})
-- 
2.9.3

Re: [PATCH net-next 1/3] samples/bpf: add -Wno-unknown-warning-option to clang

[Daniel Borkmann]

On 04/24/2017 03:31 PM, Alexander Alemayhu wrote:
> I was initially going to remove '-Wno-address-of-packed-member' because I
> thought it was not supposed to be there but Daniel suggested using
> '-Wno-unknown-warning-option'.
>
> This silences several warnings similiar to the one below
>
> warning: unknown warning option '-Wno-address-of-packed-member' [-Wunknown-warning-option]
> 1 warning generated.

Yeah, that feature seems fairly new (Feb 2017 accepted if I
see this correctly): https://reviews.llvm.org/D20561

Given the -Wno-address-of-packed-member was there to silence
warnings in the first place, we should also silence warnings
when -Wno-address-of-packed-member is unknown to clang/llvm.

[...]
>
> Signed-off-by: Alexander Alemayhu <alexander@alemayhu.com>

Acked-by: Daniel Borkmann <daniel@iogearbox.net>

Re: [PATCH net-next 2/3] samples/bpf: add static to function with no prototype

[Daniel Borkmann]

On 04/24/2017 03:31 PM, Alexander Alemayhu wrote:
> Fixes the following warning
>
> samples/bpf/cookie_uid_helper_example.c: At top level:
> samples/bpf/cookie_uid_helper_example.c:276:6: warning: no previous prototype for ‘finish’ [-Wmissing-prototypes]
>   void finish(int ret)
>        ^~~~~~
>    HOSTLD  samples/bpf/per_socket_stats_example
>
> Signed-off-by: Alexander Alemayhu <alexander@alemayhu.com>

Acked-by: Daniel Borkmann <daniel@iogearbox.net>

Re: [PATCH net-next 3/3] samples/bpf: check before defining offsetof

[Daniel Borkmann]

On 04/24/2017 03:31 PM, Alexander Alemayhu wrote:
> Fixes the following warning
>
> samples/bpf/test_lru_dist.c:28:0: warning: "offsetof" redefined
>   #define offsetof(TYPE, MEMBER) ((size_t)&((TYPE *)0)->MEMBER)
>
> In file included from ./tools/lib/bpf/bpf.h:25:0,
>                   from samples/bpf/libbpf.h:5,
>                   from samples/bpf/test_lru_dist.c:24:
> /usr/lib/gcc/x86_64-redhat-linux/6.3.1/include/stddef.h:417:0: note: this is the location of the previous definition
>   #define offsetof(TYPE, MEMBER) __builtin_offsetof (TYPE, MEMBER)
>
> Signed-off-by: Alexander Alemayhu <alexander@alemayhu.com>

Acked-by: Daniel Borkmann <daniel@iogearbox.net>

Re: [PATCH net-next 0/3] Misc BPF cleanup

[Alexei Starovoitov]

On 4/24/17 6:31 AM, Alexander Alemayhu wrote:
> Hei,
>
> while looking into making the Makefile in samples/bpf better handle O= I saw
> several warnings when running `make clean && make samples/bpf/`. This series
> reduces those warnings.

Cleanup looks good to me.
Acked-by: Alexei Starovoitov <ast@kernel.org>

Re: [PATCH net-next 0/3] Misc BPF cleanup

[David Miller]

From: Alexander Alemayhu <alexander@alemayhu.com>
Date: Mon, 24 Apr 2017 15:31:05 +0200

> while looking into making the Makefile in samples/bpf better handle O= I saw
> several warnings when running `make clean && make samples/bpf/`. This series
> reduces those warnings.

Series applied, thanks.

RE: [PATCH net-next 3/3] samples/bpf: check before defining offsetof

[David Laight]

From: Daniel Borkmann
> Sent: 24 April 2017 15:41
> To: Alexander Alemayhu; netdev@vger.kernel.org
> Cc: ast@fb.com
> Subject: Re: [PATCH net-next 3/3] samples/bpf: check before defining offsetof
> 
> On 04/24/2017 03:31 PM, Alexander Alemayhu wrote:
> > Fixes the following warning
> >
> > samples/bpf/test_lru_dist.c:28:0: warning: "offsetof" redefined
> >   #define offsetof(TYPE, MEMBER) ((size_t)&((TYPE *)0)->MEMBER)
> >
> > In file included from ./tools/lib/bpf/bpf.h:25:0,
> >                   from samples/bpf/libbpf.h:5,
> >                   from samples/bpf/test_lru_dist.c:24:
> > /usr/lib/gcc/x86_64-redhat-linux/6.3.1/include/stddef.h:417:0: note: this is the location of the
> previous definition
> >   #define offsetof(TYPE, MEMBER) __builtin_offsetof (TYPE, MEMBER)
> >
> > Signed-off-by: Alexander Alemayhu <alexander@alemayhu.com>
> 
> Acked-by: Daniel Borkmann <daniel@iogearbox.net>

Isn't the correct fix to include stddef.h ?

	David

Re: [PATCH net-next 3/3] samples/bpf: check before defining offsetof

[Alexander Alemayhu]

On Tue, Apr 25, 2017 at 02:27:16PM +0000, David Laight wrote:
> 
> Isn't the correct fix to include stddef.h ?
>
If you think it's the correct fix, please send a patch to netdev.

Thanks.

-- 
Mit freundlichen Grüßen

Alexander Alemayhu