[v3,3/8] tools include: add dis-asm-compat.h to handle version differences

Commit Message

Andres Freund Aug. 1, 2022, 1:38 a.m. UTC

binutils changed the signature of init_disassemble_info(), which now causes
compilation failures for tools/{perf,bpf}, e.g. on debian unstable.
Relevant binutils commit:
https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=60a3da00bd5407f07

This commit introduces a wrapper for init_disassemble_info(), to avoid
spreading #ifdef DISASM_INIT_STYLED to a bunch of places. Subsequent
commits will use it to fix the build failures.

It likely is worth adding a wrapper for disassember(), to avoid the already
existing DISASM_FOUR_ARGS_SIGNATURE ifdefery.

Cc: Alexei Starovoitov <[e-mail]>
Cc: Arnaldo Carvalho de Melo <[e-mail]>
Cc: Sedat Dilek <[e-mail]>
Cc: Quentin Monnet <[e-mail]>
Cc: Ben Hutchings <[e-mail]>
Link: http://lore.kernel.org/lkml/[e-mail]
Signed-off-by: Andres Freund <[e-mail]>
Signed-off-by: Ben Hutchings <[e-mail]>
---
 tools/include/tools/dis-asm-compat.h | 55 ++++++++++++++++++++++++++++
 1 file changed, 55 insertions(+)
 create mode 100644 tools/include/tools/dis-asm-compat.h

Comments

Arnaldo Carvalho de Melo Aug. 1, 2022, 6:05 p.m. UTC | #1

Em Sun, Jul 31, 2022 at 06:38:29PM -0700, Andres Freund escreveu:
> binutils changed the signature of init_disassemble_info(), which now causes
> compilation failures for tools/{perf,bpf}, e.g. on debian unstable.
> Relevant binutils commit:
> https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=60a3da00bd5407f07
> 
> This commit introduces a wrapper for init_disassemble_info(), to avoid
> spreading #ifdef DISASM_INIT_STYLED to a bunch of places. Subsequent
> commits will use it to fix the build failures.
> 
> It likely is worth adding a wrapper for disassember(), to avoid the already
> existing DISASM_FOUR_ARGS_SIGNATURE ifdefery.
> 
> Cc: Alexei Starovoitov <[e-mail]>
> Cc: Arnaldo Carvalho de Melo <[e-mail]>
> Cc: Sedat Dilek <[e-mail]>
> Cc: Quentin Monnet <[e-mail]>
> Cc: Ben Hutchings <[e-mail]>
> Link: http://lore.kernel.org/lkml/[e-mail]
> Signed-off-by: Andres Freund <[e-mail]>
> Signed-off-by: Ben Hutchings <[e-mail]>

So, who is the author of this patch? Ben? b4 complained about it:

NOTE: some trailers ignored due to from/email mismatches:
    ! Trailer: Signed-off-by: Ben Hutchings <[e-mail]>
     Msg From: Andres Freund <[e-mail]>
NOTE: Rerun with -S to apply them anyway

If it is Ben, then we would need a:

From: Ben Hutchings <[e-mail]>

At the beginning of the patch, right?

- Arnaldo

> ---
>  tools/include/tools/dis-asm-compat.h | 55 ++++++++++++++++++++++++++++
>  1 file changed, 55 insertions(+)
>  create mode 100644 tools/include/tools/dis-asm-compat.h
> 
> diff --git a/tools/include/tools/dis-asm-compat.h b/tools/include/tools/dis-asm-compat.h
> new file mode 100644
> index 000000000000..70f331e23ed3
> --- /dev/null
> +++ b/tools/include/tools/dis-asm-compat.h
> @@ -0,0 +1,55 @@
> +/* SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause */
> +#ifndef _TOOLS_DIS_ASM_COMPAT_H
> +#define _TOOLS_DIS_ASM_COMPAT_H
> +
> +#include <stdio.h>
> +#include <dis-asm.h>
> +
> +/* define types for older binutils version, to centralize ifdef'ery a bit */
> +#ifndef DISASM_INIT_STYLED
> +enum disassembler_style {DISASSEMBLER_STYLE_NOT_EMPTY};
> +typedef int (*fprintf_styled_ftype) (void *, enum disassembler_style, const char*, ...);
> +#endif
> +
> +/*
> + * Trivial fprintf wrapper to be used as the fprintf_styled_func argument to
> + * init_disassemble_info_compat() when normal fprintf suffices.
> + */
> +static inline int fprintf_styled(void *out,
> +				 enum disassembler_style style,
> +				 const char *fmt, ...)
> +{
> +	va_list args;
> +	int r;
> +
> +	(void)style;
> +
> +	va_start(args, fmt);
> +	r = vfprintf(out, fmt, args);
> +	va_end(args);
> +
> +	return r;
> +}
> +
> +/*
> + * Wrapper for init_disassemble_info() that hides version
> + * differences. Depending on binutils version and architecture either
> + * fprintf_func or fprintf_styled_func will be called.
> + */
> +static inline void init_disassemble_info_compat(struct disassemble_info *info,
> +						void *stream,
> +						fprintf_ftype unstyled_func,
> +						fprintf_styled_ftype styled_func)
> +{
> +#ifdef DISASM_INIT_STYLED
> +	init_disassemble_info(info, stream,
> +			      unstyled_func,
> +			      styled_func);
> +#else
> +	(void)styled_func;
> +	init_disassemble_info(info, stream,
> +			      unstyled_func);
> +#endif
> +}
> +
> +#endif /* _TOOLS_DIS_ASM_COMPAT_H */
> -- 
> 2.37.0.3.g30cc8d0f14

Andres Freund Aug. 1, 2022, 6:10 p.m. UTC | #2

Hi,

On 2022-08-01 15:05:00 -0300, Arnaldo Carvalho de Melo wrote:
> Em Sun, Jul 31, 2022 at 06:38:29PM -0700, Andres Freund escreveu:
> > binutils changed the signature of init_disassemble_info(), which now causes
> > compilation failures for tools/{perf,bpf}, e.g. on debian unstable.
> > Relevant binutils commit:
> > https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=60a3da00bd5407f07
> > 
> > This commit introduces a wrapper for init_disassemble_info(), to avoid
> > spreading #ifdef DISASM_INIT_STYLED to a bunch of places. Subsequent
> > commits will use it to fix the build failures.
> > 
> > It likely is worth adding a wrapper for disassember(), to avoid the already
> > existing DISASM_FOUR_ARGS_SIGNATURE ifdefery.
> > 
> > Cc: Alexei Starovoitov <[e-mail]>
> > Cc: Arnaldo Carvalho de Melo <[e-mail]>
> > Cc: Sedat Dilek <[e-mail]>
> > Cc: Quentin Monnet <[e-mail]>
> > Cc: Ben Hutchings <[e-mail]>
> > Link: http://lore.kernel.org/lkml/[e-mail]
> > Signed-off-by: Andres Freund <[e-mail]>
> > Signed-off-by: Ben Hutchings <[e-mail]>
> 
> So, who is the author of this patch? Ben? b4 complained about it:

I squashed a fixup of Ben into my patch (moving the include in annotate.c into
the HAVE_LIBBFD_SUPPORT section). I don't know what the proper procedure is
for that - I'd asked in
https://lore.kernel.org/[e-mail]


> NOTE: some trailers ignored due to from/email mismatches:
>     ! Trailer: Signed-off-by: Ben Hutchings <[e-mail]>
>      Msg From: Andres Freund <[e-mail]>
> NOTE: Rerun with -S to apply them anyway
> 
> If it is Ben, then we would need a:
> 
> From: Ben Hutchings <[e-mail]>
> 
> At the beginning of the patch, right?

I don't know, I interact with the kernel processes too rarely...

Greetings,

Andres Freund

Patch

diff --git a/tools/include/tools/dis-asm-compat.h b/tools/include/tools/dis-asm-compat.h
new file mode 100644
index 000000000000..70f331e23ed3
--- /dev/null
+++ b/tools/include/tools/dis-asm-compat.h
@@ -0,0 +1,55 @@ 
+/* SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause */
+#ifndef _TOOLS_DIS_ASM_COMPAT_H
+#define _TOOLS_DIS_ASM_COMPAT_H
+
+#include <stdio.h>
+#include <dis-asm.h>
+
+/* define types for older binutils version, to centralize ifdef'ery a bit */
+#ifndef DISASM_INIT_STYLED
+enum disassembler_style {DISASSEMBLER_STYLE_NOT_EMPTY};
+typedef int (*fprintf_styled_ftype) (void *, enum disassembler_style, const char*, ...);
+#endif
+
+/*
+ * Trivial fprintf wrapper to be used as the fprintf_styled_func argument to
+ * init_disassemble_info_compat() when normal fprintf suffices.
+ */
+static inline int fprintf_styled(void *out,
+				 enum disassembler_style style,
+				 const char *fmt, ...)
+{
+	va_list args;
+	int r;
+
+	(void)style;
+
+	va_start(args, fmt);
+	r = vfprintf(out, fmt, args);
+	va_end(args);
+
+	return r;
+}
+
+/*
+ * Wrapper for init_disassemble_info() that hides version
+ * differences. Depending on binutils version and architecture either
+ * fprintf_func or fprintf_styled_func will be called.
+ */
+static inline void init_disassemble_info_compat(struct disassemble_info *info,
+						void *stream,
+						fprintf_ftype unstyled_func,
+						fprintf_styled_ftype styled_func)
+{
+#ifdef DISASM_INIT_STYLED
+	init_disassemble_info(info, stream,
+			      unstyled_func,
+			      styled_func);
+#else
+	(void)styled_func;
+	init_disassemble_info(info, stream,
+			      unstyled_func);
+#endif
+}
+
+#endif /* _TOOLS_DIS_ASM_COMPAT_H */