2022-08-02 23:56:49

by James Hilliard

Subject: [PATCH] libbpf: ensure functions with always_inline attribute are inline

GCC expects the always_inline attribute to only be set on inline
functions, as such we should make all functions with this attribute
inline.

Fixes errors like:
/home/buildroot/bpf-next/tools/testing/selftests/bpf/tools/include/bpf/bpf_tracing.h:439:1: error: ‘always_inline’ function might not be inlinable [-Werror=attributes]
439 | ____##name(unsigned long long *ctx, ##args)
| ^~~~

Signed-off-by: James Hilliard <[email protected]>
---
tools/lib/bpf/bpf_tracing.h | 14 +++++++-------
tools/lib/bpf/usdt.bpf.h | 4 ++--
2 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/tools/lib/bpf/bpf_tracing.h b/tools/lib/bpf/bpf_tracing.h
index 43ca3aff2292..ae67fcee912c 100644
--- a/tools/lib/bpf/bpf_tracing.h
+++ b/tools/lib/bpf/bpf_tracing.h
@@ -426,7 +426,7 @@ struct pt_regs;
*/
#define BPF_PROG(name, args...) \
name(unsigned long long *ctx); \
-static __attribute__((always_inline)) typeof(name(0)) \
+static inline __attribute__((always_inline)) typeof(name(0)) \
____##name(unsigned long long *ctx, ##args); \
typeof(name(0)) name(unsigned long long *ctx) \
{ \
@@ -435,7 +435,7 @@ typeof(name(0)) name(unsigned long long *ctx) \
return ____##name(___bpf_ctx_cast(args)); \
_Pragma("GCC diagnostic pop") \
} \
-static __attribute__((always_inline)) typeof(name(0)) \
+static inline __attribute__((always_inline)) typeof(name(0)) \
____##name(unsigned long long *ctx, ##args)

struct pt_regs;
@@ -460,7 +460,7 @@ struct pt_regs;
*/
#define BPF_KPROBE(name, args...) \
name(struct pt_regs *ctx); \
-static __attribute__((always_inline)) typeof(name(0)) \
+static inline __attribute__((always_inline)) typeof(name(0)) \
____##name(struct pt_regs *ctx, ##args); \
typeof(name(0)) name(struct pt_regs *ctx) \
{ \
@@ -469,7 +469,7 @@ typeof(name(0)) name(struct pt_regs *ctx) \
return ____##name(___bpf_kprobe_args(args)); \
_Pragma("GCC diagnostic pop") \
} \
-static __attribute__((always_inline)) typeof(name(0)) \
+static inline __attribute__((always_inline)) typeof(name(0)) \
____##name(struct pt_regs *ctx, ##args)

#define ___bpf_kretprobe_args0() ctx
@@ -484,7 +484,7 @@ ____##name(struct pt_regs *ctx, ##args)
*/
#define BPF_KRETPROBE(name, args...) \
name(struct pt_regs *ctx); \
-static __attribute__((always_inline)) typeof(name(0)) \
+static inline __attribute__((always_inline)) typeof(name(0)) \
____##name(struct pt_regs *ctx, ##args); \
typeof(name(0)) name(struct pt_regs *ctx) \
{ \
@@ -540,7 +540,7 @@ static __always_inline typeof(name(0)) ____##name(struct pt_regs *ctx, ##args)
#define BPF_KSYSCALL(name, args...) \
name(struct pt_regs *ctx); \
extern _Bool LINUX_HAS_SYSCALL_WRAPPER __kconfig; \
-static __attribute__((always_inline)) typeof(name(0)) \
+static inline __attribute__((always_inline)) typeof(name(0)) \
____##name(struct pt_regs *ctx, ##args); \
typeof(name(0)) name(struct pt_regs *ctx) \
{ \
@@ -555,7 +555,7 @@ typeof(name(0)) name(struct pt_regs *ctx) \
return ____##name(___bpf_syscall_args(args)); \
_Pragma("GCC diagnostic pop") \
} \
-static __attribute__((always_inline)) typeof(name(0)) \
+static inline __attribute__((always_inline)) typeof(name(0)) \
____##name(struct pt_regs *ctx, ##args)

#define BPF_KPROBE_SYSCALL BPF_KSYSCALL
diff --git a/tools/lib/bpf/usdt.bpf.h b/tools/lib/bpf/usdt.bpf.h
index 4f2adc0bd6ca..2bd2d80b3751 100644
--- a/tools/lib/bpf/usdt.bpf.h
+++ b/tools/lib/bpf/usdt.bpf.h
@@ -232,7 +232,7 @@ long bpf_usdt_cookie(struct pt_regs *ctx)
*/
#define BPF_USDT(name, args...) \
name(struct pt_regs *ctx); \
-static __attribute__((always_inline)) typeof(name(0)) \
+static inline __attribute__((always_inline)) typeof(name(0)) \
____##name(struct pt_regs *ctx, ##args); \
typeof(name(0)) name(struct pt_regs *ctx) \
{ \
@@ -241,7 +241,7 @@ typeof(name(0)) name(struct pt_regs *ctx) \
return ____##name(___bpf_usdt_args(args)); \
_Pragma("GCC diagnostic pop") \
} \
-static __attribute__((always_inline)) typeof(name(0)) \
+static inline __attribute__((always_inline)) typeof(name(0)) \
____##name(struct pt_regs *ctx, ##args)

#endif /* __USDT_BPF_H__ */
--
2.34.1

2022-08-03 08:20:39

by Jiri Olsa

Subject: Re: [PATCH] libbpf: ensure functions with always_inline attribute are inline

On Tue, Aug 02, 2022 at 05:27:41PM -0600, James Hilliard wrote:
> GCC expects the always_inline attribute to only be set on inline
> functions, as such we should make all functions with this attribute
> inline.
>
> Fixes errors like:
> /home/buildroot/bpf-next/tools/testing/selftests/bpf/tools/include/bpf/bpf_tracing.h:439:1: error: ‘always_inline’ function might not be inlinable [-Werror=attributes]
> 439 | ____##name(unsigned long long *ctx, ##args)
> | ^~~~
>
> Signed-off-by: James Hilliard <[email protected]>
> ---
> tools/lib/bpf/bpf_tracing.h | 14 +++++++-------
> tools/lib/bpf/usdt.bpf.h | 4 ++--
> 2 files changed, 9 insertions(+), 9 deletions(-)
>
> diff --git a/tools/lib/bpf/bpf_tracing.h b/tools/lib/bpf/bpf_tracing.h
> index 43ca3aff2292..ae67fcee912c 100644
> --- a/tools/lib/bpf/bpf_tracing.h
> +++ b/tools/lib/bpf/bpf_tracing.h
> @@ -426,7 +426,7 @@ struct pt_regs;
> */
> #define BPF_PROG(name, args...) \
> name(unsigned long long *ctx); \
> -static __attribute__((always_inline)) typeof(name(0)) \
> +static inline __attribute__((always_inline)) typeof(name(0)) \

could you use __always_inline that does exactly that?

jirka

> ____##name(unsigned long long *ctx, ##args); \
> typeof(name(0)) name(unsigned long long *ctx) \
> { \
> @@ -435,7 +435,7 @@ typeof(name(0)) name(unsigned long long *ctx) \
> return ____##name(___bpf_ctx_cast(args)); \
> _Pragma("GCC diagnostic pop") \
> } \
> -static __attribute__((always_inline)) typeof(name(0)) \
> +static inline __attribute__((always_inline)) typeof(name(0)) \
> ____##name(unsigned long long *ctx, ##args)
>
> struct pt_regs;
> @@ -460,7 +460,7 @@ struct pt_regs;
> */
> #define BPF_KPROBE(name, args...) \
> name(struct pt_regs *ctx); \
> -static __attribute__((always_inline)) typeof(name(0)) \
> +static inline __attribute__((always_inline)) typeof(name(0)) \
> ____##name(struct pt_regs *ctx, ##args); \
> typeof(name(0)) name(struct pt_regs *ctx) \
> { \
> @@ -469,7 +469,7 @@ typeof(name(0)) name(struct pt_regs *ctx) \
> return ____##name(___bpf_kprobe_args(args)); \
> _Pragma("GCC diagnostic pop") \
> } \
> -static __attribute__((always_inline)) typeof(name(0)) \
> +static inline __attribute__((always_inline)) typeof(name(0)) \
> ____##name(struct pt_regs *ctx, ##args)
>
> #define ___bpf_kretprobe_args0() ctx
> @@ -484,7 +484,7 @@ ____##name(struct pt_regs *ctx, ##args)
> */
> #define BPF_KRETPROBE(name, args...) \
> name(struct pt_regs *ctx); \
> -static __attribute__((always_inline)) typeof(name(0)) \
> +static inline __attribute__((always_inline)) typeof(name(0)) \
> ____##name(struct pt_regs *ctx, ##args); \
> typeof(name(0)) name(struct pt_regs *ctx) \
> { \
> @@ -540,7 +540,7 @@ static __always_inline typeof(name(0)) ____##name(struct pt_regs *ctx, ##args)
> #define BPF_KSYSCALL(name, args...) \
> name(struct pt_regs *ctx); \
> extern _Bool LINUX_HAS_SYSCALL_WRAPPER __kconfig; \
> -static __attribute__((always_inline)) typeof(name(0)) \
> +static inline __attribute__((always_inline)) typeof(name(0)) \
> ____##name(struct pt_regs *ctx, ##args); \
> typeof(name(0)) name(struct pt_regs *ctx) \
> { \
> @@ -555,7 +555,7 @@ typeof(name(0)) name(struct pt_regs *ctx) \
> return ____##name(___bpf_syscall_args(args)); \
> _Pragma("GCC diagnostic pop") \
> } \
> -static __attribute__((always_inline)) typeof(name(0)) \
> +static inline __attribute__((always_inline)) typeof(name(0)) \
> ____##name(struct pt_regs *ctx, ##args)
>
> #define BPF_KPROBE_SYSCALL BPF_KSYSCALL
> diff --git a/tools/lib/bpf/usdt.bpf.h b/tools/lib/bpf/usdt.bpf.h
> index 4f2adc0bd6ca..2bd2d80b3751 100644
> --- a/tools/lib/bpf/usdt.bpf.h
> +++ b/tools/lib/bpf/usdt.bpf.h
> @@ -232,7 +232,7 @@ long bpf_usdt_cookie(struct pt_regs *ctx)
> */
> #define BPF_USDT(name, args...) \
> name(struct pt_regs *ctx); \
> -static __attribute__((always_inline)) typeof(name(0)) \
> +static inline __attribute__((always_inline)) typeof(name(0)) \
> ____##name(struct pt_regs *ctx, ##args); \
> typeof(name(0)) name(struct pt_regs *ctx) \
> { \
> @@ -241,7 +241,7 @@ typeof(name(0)) name(struct pt_regs *ctx) \
> return ____##name(___bpf_usdt_args(args)); \
> _Pragma("GCC diagnostic pop") \
> } \
> -static __attribute__((always_inline)) typeof(name(0)) \
> +static inline __attribute__((always_inline)) typeof(name(0)) \
> ____##name(struct pt_regs *ctx, ##args)
>
> #endif /* __USDT_BPF_H__ */
> --
> 2.34.1
>

2022-08-03 15:51:15

by James Hilliard

Subject: Re: [PATCH] libbpf: ensure functions with always_inline attribute are inline

On Wed, Aug 3, 2022 at 2:19 AM Jiri Olsa <[email protected]> wrote:
>
> On Tue, Aug 02, 2022 at 05:27:41PM -0600, James Hilliard wrote:
> > GCC expects the always_inline attribute to only be set on inline
> > functions, as such we should make all functions with this attribute
> > inline.
> >
> > Fixes errors like:
> > /home/buildroot/bpf-next/tools/testing/selftests/bpf/tools/include/bpf/bpf_tracing.h:439:1: error: ‘always_inline’ function might not be inlinable [-Werror=attributes]
> > 439 | ____##name(unsigned long long *ctx, ##args)
> > | ^~~~
> >
> > Signed-off-by: James Hilliard <[email protected]>
> > ---
> > tools/lib/bpf/bpf_tracing.h | 14 +++++++-------
> > tools/lib/bpf/usdt.bpf.h | 4 ++--
> > 2 files changed, 9 insertions(+), 9 deletions(-)
> >
> > diff --git a/tools/lib/bpf/bpf_tracing.h b/tools/lib/bpf/bpf_tracing.h
> > index 43ca3aff2292..ae67fcee912c 100644
> > --- a/tools/lib/bpf/bpf_tracing.h
> > +++ b/tools/lib/bpf/bpf_tracing.h
> > @@ -426,7 +426,7 @@ struct pt_regs;
> > */
> > #define BPF_PROG(name, args...) \
> > name(unsigned long long *ctx); \
> > -static __attribute__((always_inline)) typeof(name(0)) \
> > +static inline __attribute__((always_inline)) typeof(name(0)) \
>
> could you use __always_inline that does exactly that?

Sure, changed to use the __always_inline macro in v2:
https://lore.kernel.org/bpf/[email protected]/

>
> jirka
>
> > ____##name(unsigned long long *ctx, ##args); \
> > typeof(name(0)) name(unsigned long long *ctx) \
> > { \
> > @@ -435,7 +435,7 @@ typeof(name(0)) name(unsigned long long *ctx) \
> > return ____##name(___bpf_ctx_cast(args)); \
> > _Pragma("GCC diagnostic pop") \
> > } \
> > -static __attribute__((always_inline)) typeof(name(0)) \
> > +static inline __attribute__((always_inline)) typeof(name(0)) \
> > ____##name(unsigned long long *ctx, ##args)
> >
> > struct pt_regs;
> > @@ -460,7 +460,7 @@ struct pt_regs;
> > */
> > #define BPF_KPROBE(name, args...) \
> > name(struct pt_regs *ctx); \
> > -static __attribute__((always_inline)) typeof(name(0)) \
> > +static inline __attribute__((always_inline)) typeof(name(0)) \
> > ____##name(struct pt_regs *ctx, ##args); \
> > typeof(name(0)) name(struct pt_regs *ctx) \
> > { \
> > @@ -469,7 +469,7 @@ typeof(name(0)) name(struct pt_regs *ctx) \
> > return ____##name(___bpf_kprobe_args(args)); \
> > _Pragma("GCC diagnostic pop") \
> > } \
> > -static __attribute__((always_inline)) typeof(name(0)) \
> > +static inline __attribute__((always_inline)) typeof(name(0)) \
> > ____##name(struct pt_regs *ctx, ##args)
> >
> > #define ___bpf_kretprobe_args0() ctx
> > @@ -484,7 +484,7 @@ ____##name(struct pt_regs *ctx, ##args)
> > */
> > #define BPF_KRETPROBE(name, args...) \
> > name(struct pt_regs *ctx); \
> > -static __attribute__((always_inline)) typeof(name(0)) \
> > +static inline __attribute__((always_inline)) typeof(name(0)) \
> > ____##name(struct pt_regs *ctx, ##args); \
> > typeof(name(0)) name(struct pt_regs *ctx) \
> > { \
> > @@ -540,7 +540,7 @@ static __always_inline typeof(name(0)) ____##name(struct pt_regs *ctx, ##args)
> > #define BPF_KSYSCALL(name, args...) \
> > name(struct pt_regs *ctx); \
> > extern _Bool LINUX_HAS_SYSCALL_WRAPPER __kconfig; \
> > -static __attribute__((always_inline)) typeof(name(0)) \
> > +static inline __attribute__((always_inline)) typeof(name(0)) \
> > ____##name(struct pt_regs *ctx, ##args); \
> > typeof(name(0)) name(struct pt_regs *ctx) \
> > { \
> > @@ -555,7 +555,7 @@ typeof(name(0)) name(struct pt_regs *ctx) \
> > return ____##name(___bpf_syscall_args(args)); \
> > _Pragma("GCC diagnostic pop") \
> > } \
> > -static __attribute__((always_inline)) typeof(name(0)) \
> > +static inline __attribute__((always_inline)) typeof(name(0)) \
> > ____##name(struct pt_regs *ctx, ##args)
> >
> > #define BPF_KPROBE_SYSCALL BPF_KSYSCALL
> > diff --git a/tools/lib/bpf/usdt.bpf.h b/tools/lib/bpf/usdt.bpf.h
> > index 4f2adc0bd6ca..2bd2d80b3751 100644
> > --- a/tools/lib/bpf/usdt.bpf.h
> > +++ b/tools/lib/bpf/usdt.bpf.h
> > @@ -232,7 +232,7 @@ long bpf_usdt_cookie(struct pt_regs *ctx)
> > */
> > #define BPF_USDT(name, args...) \
> > name(struct pt_regs *ctx); \
> > -static __attribute__((always_inline)) typeof(name(0)) \
> > +static inline __attribute__((always_inline)) typeof(name(0)) \
> > ____##name(struct pt_regs *ctx, ##args); \
> > typeof(name(0)) name(struct pt_regs *ctx) \
> > { \
> > @@ -241,7 +241,7 @@ typeof(name(0)) name(struct pt_regs *ctx) \
> > return ____##name(___bpf_usdt_args(args)); \
> > _Pragma("GCC diagnostic pop") \
> > } \
> > -static __attribute__((always_inline)) typeof(name(0)) \
> > +static inline __attribute__((always_inline)) typeof(name(0)) \
> > ____##name(struct pt_regs *ctx, ##args)
> >
> > #endif /* __USDT_BPF_H__ */
> > --
> > 2.34.1
> >