2021-01-25 05:07:33

by Tiezhu Yang

[permalink] [raw]
Subject: [PATCH bpf-next v2] samples/bpf: Set flag __SANE_USERSPACE_TYPES__ for MIPS to fix build warnings

There exists many build warnings when make M=samples/bpf on the Loongson
platform, this issue is MIPS related, x86 compiles just fine.

Here are some warnings:

CC samples/bpf/ibumad_user.o
samples/bpf/ibumad_user.c: In function ‘dump_counts’:
samples/bpf/ibumad_user.c:46:24: warning: format ‘%llu’ expects argument of type ‘long long unsigned int’, but argument 3 has type ‘__u64’ {aka ‘long unsigned int’} [-Wformat=]
printf("0x%02x : %llu\n", key, value);
~~~^ ~~~~~
%lu
CC samples/bpf/offwaketime_user.o
samples/bpf/offwaketime_user.c: In function ‘print_ksym’:
samples/bpf/offwaketime_user.c:34:17: warning: format ‘%llx’ expects argument of type ‘long long unsigned int’, but argument 3 has type ‘__u64’ {aka ‘long unsigned int’} [-Wformat=]
printf("%s/%llx;", sym->name, addr);
~~~^ ~~~~
%lx
samples/bpf/offwaketime_user.c: In function ‘print_stack’:
samples/bpf/offwaketime_user.c:68:17: warning: format ‘%lld’ expects argument of type ‘long long int’, but argument 3 has type ‘__u64’ {aka ‘long unsigned int’} [-Wformat=]
printf(";%s %lld\n", key->waker, count);
~~~^ ~~~~~
%ld

MIPS needs __SANE_USERSPACE_TYPES__ before <linux/types.h> to select
'int-ll64.h' in arch/mips/include/uapi/asm/types.h, then it can avoid
build warnings when printing __u64 with %llu, %llx or %lld.

The header tools/include/linux/types.h defines __SANE_USERSPACE_TYPES__,
it seems that we can include <linux/types.h> in the source files which
have build warnings, but it has no effect due to actually it includes
usr/include/linux/types.h instead of tools/include/linux/types.h, the
problem is that "usr/include" is preferred first than "tools/include"
in samples/bpf/Makefile, that sounds like a ugly hack to -Itools/include
before -Iusr/include.

So define __SANE_USERSPACE_TYPES__ for MIPS in samples/bpf/Makefile
is proper, if add "TPROGS_CFLAGS += -D__SANE_USERSPACE_TYPES__" in
samples/bpf/Makefile, it appears the following error:

Auto-detecting system features:
... libelf: [ on ]
... zlib: [ on ]
... bpf: [ OFF ]

BPF API too old
make[3]: *** [Makefile:293: bpfdep] Error 1
make[2]: *** [Makefile:156: all] Error 2

With #ifndef __SANE_USERSPACE_TYPES__ in tools/include/linux/types.h,
the above error has gone and this ifndef change does not hurt other
compilations.

Signed-off-by: Tiezhu Yang <[email protected]>
---

v2: Update the commit message

samples/bpf/Makefile | 4 ++++
tools/include/linux/types.h | 3 +++
2 files changed, 7 insertions(+)

diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile
index 26fc96c..27de306 100644
--- a/samples/bpf/Makefile
+++ b/samples/bpf/Makefile
@@ -183,6 +183,10 @@ BPF_EXTRA_CFLAGS := $(ARM_ARCH_SELECTOR)
TPROGS_CFLAGS += $(ARM_ARCH_SELECTOR)
endif

+ifeq ($(ARCH), mips)
+TPROGS_CFLAGS += -D__SANE_USERSPACE_TYPES__
+endif
+
TPROGS_CFLAGS += -Wall -O2
TPROGS_CFLAGS += -Wmissing-prototypes
TPROGS_CFLAGS += -Wstrict-prototypes
diff --git a/tools/include/linux/types.h b/tools/include/linux/types.h
index 154eb4e..e9c5a21 100644
--- a/tools/include/linux/types.h
+++ b/tools/include/linux/types.h
@@ -6,7 +6,10 @@
#include <stddef.h>
#include <stdint.h>

+#ifndef __SANE_USERSPACE_TYPES__
#define __SANE_USERSPACE_TYPES__ /* For PPC64, to get LL64 types */
+#endif
+
#include <asm/types.h>
#include <asm/posix_types.h>

--
2.1.0


2021-01-25 23:33:06

by patchwork-bot+netdevbpf

[permalink] [raw]
Subject: Re: [PATCH bpf-next v2] samples/bpf: Set flag __SANE_USERSPACE_TYPES__ for MIPS to fix build warnings

Hello:

This patch was applied to bpf/bpf-next.git (refs/heads/master):

On Mon, 25 Jan 2021 13:05:46 +0800 you wrote:
> There exists many build warnings when make M=samples/bpf on the Loongson
> platform, this issue is MIPS related, x86 compiles just fine.
>
> Here are some warnings:
>
> CC samples/bpf/ibumad_user.o
> samples/bpf/ibumad_user.c: In function ‘dump_counts’:
> samples/bpf/ibumad_user.c:46:24: warning: format ‘%llu’ expects argument of type ‘long long unsigned int’, but argument 3 has type ‘__u64’ {aka ‘long unsigned int’} [-Wformat=]
> printf("0x%02x : %llu\n", key, value);
> ~~~^ ~~~~~
> %lu
> CC samples/bpf/offwaketime_user.o
> samples/bpf/offwaketime_user.c: In function ‘print_ksym’:
> samples/bpf/offwaketime_user.c:34:17: warning: format ‘%llx’ expects argument of type ‘long long unsigned int’, but argument 3 has type ‘__u64’ {aka ‘long unsigned int’} [-Wformat=]
> printf("%s/%llx;", sym->name, addr);
> ~~~^ ~~~~
> %lx
> samples/bpf/offwaketime_user.c: In function ‘print_stack’:
> samples/bpf/offwaketime_user.c:68:17: warning: format ‘%lld’ expects argument of type ‘long long int’, but argument 3 has type ‘__u64’ {aka ‘long unsigned int’} [-Wformat=]
> printf(";%s %lld\n", key->waker, count);
> ~~~^ ~~~~~
> %ld
>
> [...]

Here is the summary with links:
- [bpf-next,v2] samples/bpf: Set flag __SANE_USERSPACE_TYPES__ for MIPS to fix build warnings
https://git.kernel.org/bpf/bpf-next/c/190d1c921ad0

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


2021-01-26 01:28:30

by Yonghong Song

[permalink] [raw]
Subject: Re: [PATCH bpf-next v2] samples/bpf: Set flag __SANE_USERSPACE_TYPES__ for MIPS to fix build warnings



On 1/24/21 9:05 PM, Tiezhu Yang wrote:
> There exists many build warnings when make M=samples/bpf on the Loongson
> platform, this issue is MIPS related, x86 compiles just fine.
>
> Here are some warnings:
>
> CC samples/bpf/ibumad_user.o
> samples/bpf/ibumad_user.c: In function ‘dump_counts’:
> samples/bpf/ibumad_user.c:46:24: warning: format ‘%llu’ expects argument of type ‘long long unsigned int’, but argument 3 has type ‘__u64’ {aka ‘long unsigned int’} [-Wformat=]
> printf("0x%02x : %llu\n", key, value);
> ~~~^ ~~~~~
> %lu
> CC samples/bpf/offwaketime_user.o
> samples/bpf/offwaketime_user.c: In function ‘print_ksym’:
> samples/bpf/offwaketime_user.c:34:17: warning: format ‘%llx’ expects argument of type ‘long long unsigned int’, but argument 3 has type ‘__u64’ {aka ‘long unsigned int’} [-Wformat=]
> printf("%s/%llx;", sym->name, addr);
> ~~~^ ~~~~
> %lx
> samples/bpf/offwaketime_user.c: In function ‘print_stack’:
> samples/bpf/offwaketime_user.c:68:17: warning: format ‘%lld’ expects argument of type ‘long long int’, but argument 3 has type ‘__u64’ {aka ‘long unsigned int’} [-Wformat=]
> printf(";%s %lld\n", key->waker, count);
> ~~~^ ~~~~~
> %ld
>
> MIPS needs __SANE_USERSPACE_TYPES__ before <linux/types.h> to select
> 'int-ll64.h' in arch/mips/include/uapi/asm/types.h, then it can avoid
> build warnings when printing __u64 with %llu, %llx or %lld.
>
> The header tools/include/linux/types.h defines __SANE_USERSPACE_TYPES__,
> it seems that we can include <linux/types.h> in the source files which
> have build warnings, but it has no effect due to actually it includes
> usr/include/linux/types.h instead of tools/include/linux/types.h, the
> problem is that "usr/include" is preferred first than "tools/include"
> in samples/bpf/Makefile, that sounds like a ugly hack to -Itools/include
> before -Iusr/include.
>
> So define __SANE_USERSPACE_TYPES__ for MIPS in samples/bpf/Makefile
> is proper, if add "TPROGS_CFLAGS += -D__SANE_USERSPACE_TYPES__" in
> samples/bpf/Makefile, it appears the following error:
>
> Auto-detecting system features:
> ... libelf: [ on ]
> ... zlib: [ on ]
> ... bpf: [ OFF ]
>
> BPF API too old
> make[3]: *** [Makefile:293: bpfdep] Error 1
> make[2]: *** [Makefile:156: all] Error 2
>
> With #ifndef __SANE_USERSPACE_TYPES__ in tools/include/linux/types.h,
> the above error has gone and this ifndef change does not hurt other
> compilations.
>
> Signed-off-by: Tiezhu Yang <[email protected]>

Acked-by: Yonghong Song <[email protected]>