Re: [PATCH bpf 1/2] samples/bpf: Set flag __SANE_USERSPACE_TYPES__ for MIPS to fix build warnings

From: Yonghong Song
Date: Wed Jan 13 2021 - 12:13:31 EST




On 1/13/21 2:57 AM, Tiezhu Yang wrote:
MIPS needs __SANE_USERSPACE_TYPES__ before <linux/types.h> to select
'int-ll64.h' in arch/mips/include/uapi/asm/types.h and avoid compile
warnings when printing __u64 with %llu, %llx or %lld.

could you mention which command produces the following warning?


printf("0x%02x : %llu\n", key, value);
~~~^ ~~~~~
%lu
printf("%s/%llx;", sym->name, addr);
~~~^ ~~~~
%lx
printf(";%s %lld\n", key->waker, count);
~~~^ ~~~~~
%ld

Signed-off-by: Tiezhu Yang <yangtiezhu@xxxxxxxxxxx>
---
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
+

This change looks okay based on description in
arch/mips/include/uapi/asm/types.h

'''
/*
* We don't use int-l64.h for the kernel anymore but still use it for
* userspace to avoid code changes.
*
* However, some user programs (e.g. perf) may not want this. They can
* flag __SANE_USERSPACE_TYPES__ to get int-ll64.h here.
*/
'''

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

What problem this patch fixed? If this header is used, you can just
change comment from "PPC64" to "PPC64/MIPS", right?

+
#include <asm/types.h>
#include <asm/posix_types.h>