Re: [PATCH tip/perf/core] perf probe: Fix 'function unused' warning

[Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>]

On 2015/05/28 11:25, Wang Nan wrote:
> By 'make build-test' a warning is found in probe-event.c that, after
> commit 419e873828 (perf probe: Show the error reason comes from
> invalid DSO) the only user of kernel_get_module_dso() is
> open_debuginfo(). Which is not compiled if HAVE_DWARF_SUPPORT not set.
> 'make build-test' found this problem when make_minimal.

Ah, right!

> 
> This patch moves kernel_get_module_dso() to HAVE_DWARF_SUPPORT ifdef
> section.
> 
> Signed-off-by: Wang Nan <wangnan0@huawei.com>

Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>

Thanks!

> ---
>  tools/perf/util/probe-event.c | 65 ++++++++++++++++++++++---------------------
>  1 file changed, 33 insertions(+), 32 deletions(-)
> 
> diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
> index 97da984..9052e7b 100644
> --- a/tools/perf/util/probe-event.c
> +++ b/tools/perf/util/probe-event.c
> @@ -200,38 +200,6 @@ static void put_target_map(struct map *map, bool user)
>  }
>  
>  
> -static int kernel_get_module_dso(const char *module, struct dso **pdso)
> -{
> -	struct dso *dso;
> -	struct map *map;
> -	const char *vmlinux_name;
> -	int ret = 0;
> -
> -	if (module) {
> -		list_for_each_entry(dso, &host_machine->kernel_dsos.head,
> -				    node) {
> -			if (strncmp(dso->short_name + 1, module,
> -				    dso->short_name_len - 2) == 0)
> -				goto found;
> -		}
> -		pr_debug("Failed to find module %s.\n", module);
> -		return -ENOENT;
> -	}
> -
> -	map = host_machine->vmlinux_maps[MAP__FUNCTION];
> -	dso = map->dso;
> -
> -	vmlinux_name = symbol_conf.vmlinux_name;
> -	dso->load_errno = 0;
> -	if (vmlinux_name)
> -		ret = dso__load_vmlinux(dso, map, vmlinux_name, false, NULL);
> -	else
> -		ret = dso__load_vmlinux_path(dso, map, NULL);
> -found:
> -	*pdso = dso;
> -	return ret;
> -}
> -
>  static int convert_exec_to_group(const char *exec, char **result)
>  {
>  	char *ptr1, *ptr2, *exec_copy;
> @@ -279,6 +247,39 @@ static void clear_probe_trace_events(struct probe_trace_event *tevs, int ntevs)
>  }
>  
>  #ifdef HAVE_DWARF_SUPPORT
> +
> +static int kernel_get_module_dso(const char *module, struct dso **pdso)
> +{
> +	struct dso *dso;
> +	struct map *map;
> +	const char *vmlinux_name;
> +	int ret = 0;
> +
> +	if (module) {
> +		list_for_each_entry(dso, &host_machine->kernel_dsos.head,
> +				    node) {
> +			if (strncmp(dso->short_name + 1, module,
> +				    dso->short_name_len - 2) == 0)
> +				goto found;
> +		}
> +		pr_debug("Failed to find module %s.\n", module);
> +		return -ENOENT;
> +	}
> +
> +	map = host_machine->vmlinux_maps[MAP__FUNCTION];
> +	dso = map->dso;
> +
> +	vmlinux_name = symbol_conf.vmlinux_name;
> +	dso->load_errno = 0;
> +	if (vmlinux_name)
> +		ret = dso__load_vmlinux(dso, map, vmlinux_name, false, NULL);
> +	else
> +		ret = dso__load_vmlinux_path(dso, map, NULL);
> +found:
> +	*pdso = dso;
> +	return ret;
> +}
> +
>  /*
>   * Some binaries like glibc have special symbols which are on the symbol
>   * table, but not in the debuginfo. If we can find the address of the
> 


-- 
Masami HIRAMATSU
Linux Technology Research Center, System Productivity Research Dept.
Center for Technology Innovation - Systems Engineering
Hitachi, Ltd., Research & Development Group
E-mail: masami.hiramatsu.pt@hitachi.com