diff mbox series

[bpf-next,v1,07/19] selftests/bpf: Fix missing ARRAY_SIZE() definition in bench.c

Message ID bc4dde77dfcd17a825d8f28f72f3292341966810.1721713597.git.tony.ambardar@gmail.com (mailing list archive)
State Accepted
Commit d44c93fc2f5a0c47b23fa03d374e45259abd92d2
Headers show
Series selftests/bpf: Improve libc portability / musl support (part 1) | expand

Commit Message

Tony Ambardar July 23, 2024, 5:54 a.m. UTC
Add a "bpf_util.h" include to avoid the following error seen compiling for
mips64el with musl libc:

  bench.c: In function 'find_benchmark':
  bench.c:590:25: error: implicit declaration of function 'ARRAY_SIZE' [-Werror=implicit-function-declaration]
    590 |         for (i = 0; i < ARRAY_SIZE(benchs); i++) {
        |                         ^~~~~~~~~~
  cc1: all warnings being treated as errors

Fixes: 8e7c2a023ac0 ("selftests/bpf: Add benchmark runner infrastructure")
Signed-off-by: Tony Ambardar <tony.ambardar@gmail.com>
---
 tools/testing/selftests/bpf/bench.c | 1 +
 1 file changed, 1 insertion(+)

Comments

Geliang Tang July 24, 2024, 7:08 a.m. UTC | #1
On Mon, 2024-07-22 at 22:54 -0700, Tony Ambardar wrote:
> Add a "bpf_util.h" include to avoid the following error seen
> compiling for
> mips64el with musl libc:
> 
>   bench.c: In function 'find_benchmark':
>   bench.c:590:25: error: implicit declaration of function
> 'ARRAY_SIZE' [-Werror=implicit-function-declaration]
>     590 |         for (i = 0; i < ARRAY_SIZE(benchs); i++) {
>         |                         ^~~~~~~~~~
>   cc1: all warnings being treated as errors

I'm curious why this error doesn't occur on other platforms. ARRAY_SIZE
is actually defined in linux/kernel.h (tools/include/linux/kernel.h). I
think you should find out why this file is not included on your
platform.

> 
> Fixes: 8e7c2a023ac0 ("selftests/bpf: Add benchmark runner
> infrastructure")
> Signed-off-by: Tony Ambardar <tony.ambardar@gmail.com>
> ---
>  tools/testing/selftests/bpf/bench.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/tools/testing/selftests/bpf/bench.c
> b/tools/testing/selftests/bpf/bench.c
> index 627b74ae041b..90dc3aca32bd 100644
> --- a/tools/testing/selftests/bpf/bench.c
> +++ b/tools/testing/selftests/bpf/bench.c
> @@ -10,6 +10,7 @@
>  #include <sys/sysinfo.h>
>  #include <signal.h>
>  #include "bench.h"
> +#include "bpf_util.h"
>  #include "testing_helpers.h"
>  
>  struct env env = {
Tony Ambardar July 25, 2024, 1:28 a.m. UTC | #2
On Wed, Jul 24, 2024 at 03:08:31PM +0800, Geliang Tang wrote:
> On Mon, 2024-07-22 at 22:54 -0700, Tony Ambardar wrote:
> > Add a "bpf_util.h" include to avoid the following error seen
> > compiling for
> > mips64el with musl libc:
> > 
> >   bench.c: In function 'find_benchmark':
> >   bench.c:590:25: error: implicit declaration of function
> > 'ARRAY_SIZE' [-Werror=implicit-function-declaration]
> >     590 |         for (i = 0; i < ARRAY_SIZE(benchs); i++) {
> >         |                         ^~~~~~~~~~
> >   cc1: all warnings being treated as errors
> 
> I'm curious why this error doesn't occur on other platforms. ARRAY_SIZE
> is actually defined in linux/kernel.h (tools/include/linux/kernel.h). I
> think you should find out why this file is not included on your
> platform.

The surprising reason is that it compiles on glibc systems by accident, due
to bench.c using get_nprocs() and needing to include <sys/sysinfo.h>. On
musl systems this header defines 'struct sysinfo', but the glibc header
version pulls in <linux/kernel.h> for this struct, which in turn drags in
ARRAY_SIZE and the rest of the kitchen sink. So not very portable...

> > 
> > Fixes: 8e7c2a023ac0 ("selftests/bpf: Add benchmark runner
> > infrastructure")
> > Signed-off-by: Tony Ambardar <tony.ambardar@gmail.com>
> > ---
> >  tools/testing/selftests/bpf/bench.c | 1 +
> >  1 file changed, 1 insertion(+)
> > 
> > diff --git a/tools/testing/selftests/bpf/bench.c
> > b/tools/testing/selftests/bpf/bench.c
> > index 627b74ae041b..90dc3aca32bd 100644
> > --- a/tools/testing/selftests/bpf/bench.c
> > +++ b/tools/testing/selftests/bpf/bench.c
> > @@ -10,6 +10,7 @@
> >  #include <sys/sysinfo.h>
> >  #include <signal.h>
> >  #include "bench.h"
> > +#include "bpf_util.h"
> >  #include "testing_helpers.h"
> >  
> >  struct env env = {
>
diff mbox series

Patch

diff --git a/tools/testing/selftests/bpf/bench.c b/tools/testing/selftests/bpf/bench.c
index 627b74ae041b..90dc3aca32bd 100644
--- a/tools/testing/selftests/bpf/bench.c
+++ b/tools/testing/selftests/bpf/bench.c
@@ -10,6 +10,7 @@ 
 #include <sys/sysinfo.h>
 #include <signal.h>
 #include "bench.h"
+#include "bpf_util.h"
 #include "testing_helpers.h"
 
 struct env env = {