Re: [PATCH 3/3] perf annotate: Try chroot filename for objdump

[Jiri Olsa <jolsa@redhat.com>]

On Fri, Jan 28, 2022 at 12:39:50PM -0800, Namhyung Kim wrote:
> Likewise, it should use a proper name in case the task runs under
> chroot.  The child_process.err was needed to set to -1 to show error
> messages properly in TUI.
> 
> Signed-off-by: Namhyung Kim <namhyung@kernel.org>
> ---
>  tools/perf/util/annotate.c | 11 +++++++++++
>  1 file changed, 11 insertions(+)
> 
> diff --git a/tools/perf/util/annotate.c b/tools/perf/util/annotate.c
> index 01900689dc00..e4c641b240df 100644
> --- a/tools/perf/util/annotate.c
> +++ b/tools/perf/util/annotate.c
> @@ -33,6 +33,7 @@
>  #include "string2.h"
>  #include "util/event.h"
>  #include "arch/common.h"
> +#include "namespaces.h"
>  #include <regex.h>
>  #include <pthread.h>
>  #include <linux/bitops.h>
> @@ -1696,6 +1697,15 @@ static int dso__disassemble_filename(struct dso *dso, char *filename, size_t fil
>  		 * DSO is the same as when 'perf record' ran.
>  		 */
>  		__symbol__join_symfs(filename, filename_size, dso->long_name);
> +
> +		if (access(filename, R_OK) && errno == ENOENT && dso->nsinfo) {
> +			char *new_name = filename_with_chroot(dso->nsinfo->pid,
> +							      filename);
> +			if (new_name) {
> +				strlcpy(filename, new_name, filename_size);
> +				free(new_name);
> +			}
> +		}
>  	}
>  
>  	free(build_id_path);
> @@ -2036,6 +2046,7 @@ static int symbol__disassemble(struct symbol *sym, struct annotate_args *args)
>  	memset(&objdump_process, 0, sizeof(objdump_process));
>  	objdump_process.argv = objdump_argv;
>  	objdump_process.out = -1;
> +	objdump_process.err = -1;

is this unrelated fix?

otherwise the whole patchset looks good to me

I guess we'd need to add something like PERF_RECORD_CHROOT to
handle and instrument sys_chroot to handle this completely?

Acked-by: Jiri Olsa <jolsa@kernel.org>

thanks,
jirka

>  	if (start_command(&objdump_process)) {
>  		pr_err("Failure starting to run %s\n", command);
>  		err = -1;
> -- 
> 2.35.0.rc2.247.g8bbb082509-goog
>