Re: [PATCH] tools/perf: Fix perf tool build error in util/pfm.c

[Arnaldo Carvalho de Melo <acme@kernel.org>]

Em Tue, Feb 07, 2023 at 03:04:47PM +0100, Thomas Richter escreveu:
> I have downloaded linux-next and build the perf tool using
> 
>  # make LIBPFM4=1
> 
> to have libpfm4 support built into perf. The build fails:
> 
>  # make LIBPFM4=1

Ian,

	Can you please take a look? Should we go this way or have some
feature test to check how that function signature should look?

- Arnaldo

> ....
> INSTALL libbpf_headers
>   CC      util/pfm.o
> util/pfm.c: In function ‘print_libpfm_event’:
> util/pfm.c:189:9: error: too many arguments to function ‘print_cb->print_event’
>   189 |         print_cb->print_event(print_state,
>       |         ^~~~~~~~
> util/pfm.c:220:25: error: too many arguments to function ‘print_cb->print_event’
>   220 |                         print_cb->print_event(print_state,
> 
> The build error is caused by
> commit d9dc8874d6ce ("perf pmu-events: Remove now unused event and metric variables")
> which changes the function prototype of
>   struct print_callbacks {
>       ...
>       void (*print_event)(...);  --> last two parameters removed.
>   };
> 
> but does not adjust the usage of this function prototype in util/pfm.c.
> In file util/pfm.c function print_event() is still invoked with 13 parameters
> instead of 11. The compile fails.
> 
> When I adjust the file util/pfm.c as in this patch, the build works file.
> Please check this patch for correctness, I have just fixed the compile
> issue.
> 
> Fixes d9dc8874d6ce ("perf pmu-events: Remove now unused event and metric variables")
> Cc: irogers@google.com
> Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
> ---
>  tools/perf/util/pfm.c | 6 ++----
>  1 file changed, 2 insertions(+), 4 deletions(-)
> 
> diff --git a/tools/perf/util/pfm.c b/tools/perf/util/pfm.c
> index ac3227ba769c..b59ba825ddc9 100644
> --- a/tools/perf/util/pfm.c
> +++ b/tools/perf/util/pfm.c
> @@ -193,8 +193,7 @@ print_libpfm_event(const struct print_callbacks *print_cb, void *print_state,
>  			/*scale_unit=*/NULL,
>  			/*deprecated=*/NULL, "PFM event",
>  			info->desc, /*long_desc=*/NULL,
> -			/*encoding_desc=*/buf->buf,
> -			/*metric_name=*/NULL, /*metric_expr=*/NULL);
> +			/*encoding_desc=*/buf->buf);
>  
>  	pfm_for_each_event_attr(j, info) {
>  		pfm_event_attr_info_t ainfo;
> @@ -224,8 +223,7 @@ print_libpfm_event(const struct print_callbacks *print_cb, void *print_state,
>  					/*scale_unit=*/NULL,
>  					/*deprecated=*/NULL, "PFM event",
>  					ainfo.desc, /*long_desc=*/NULL,
> -					/*encoding_desc=*/buf->buf,
> -					/*metric_name=*/NULL, /*metric_expr=*/NULL);
> +					/*encoding_desc=*/buf->buf);
>  		}
>  	}
>  }
> -- 
> 2.39.1
> 

-- 

- Arnaldo