Re: [PATCH] perf report: Fix some option handling on --stdio

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

Em Thu, May 14, 2015 at 12:03:26AM +0900, Namhyung Kim escreveu:
> There's a bug that perf report sometimes ignore some options on --stdio
> output.  This bug is triggered only if a related config variable is
> set.  For example, let's assume we have a following config file.

Testing, please next time indicate against what branch this is to be
applied, as I thought about perf/core, but it doesn't apply there, so
tried perf/urgent, where it applies.

- Arnaldo
 
>   $ cat ~/.perfconfig
>   [call-graph]
>     print-type = graph
>   [hist]
>     percentage = absolute
> 
> Then, following perf config will not honor some options.
> 
>   $ perf record -ag sleep 1
>   [ perf record: Woken up 1 times to write data ]
>   [ perf record: Captured and wrote 0.199 MB perf.data (77 samples) ]
> 
>   $ perf report -g none --stdio
>   # To display the perf.data header info, please use --header/--header-only options.
>   #
>   # Samples: 77  of event 'cycles'
>   # Event count (approx.): 25425383
>   #
>   # Overhead  Command          Shared Object            Symbol
>   # ........  ...............  .......................  ..............
>   #
>       16.34%  swapper          [kernel.vmlinux]         [k] intel_idle
>                       |
>                       ---intel_idle
>                          cpuidle_enter_state
>                          cpuidle_enter
>                          cpu_startup_entry
>    ...
> 
> With '-g none' option, it should not show callchains, but it still shows
> callchains.  However it works as expected on --tui output.
> 
> Similarly, '--percentage relative' option is not work and still shows a
> absolute percentage values.
> 
> Looking at the source, I found that those setting were overwritten by
> config variables when setup_pager() called.  The setup_pager() is to
> start a pager process so that it can manage long lines of output on the
> stdio mode.  But as it calls the perf_config() after parsing arguments,
> the settings were overwritten regardless of command line options.
> 
> The reason it calls perf_config() is to find the 'pager_program' which
> might be set by a config variable, I guess.  However current perf code
> does not provide the config variable for it, so it's just meaningless
> IMHO.  Eliminating the call makes the option working as expected.
> 
> Cc: Taeung Song <treeze.taeung@gmail.com>
> Signed-off-by: Namhyung Kim <namhyung@kernel.org>
> ---
>  tools/perf/util/cache.h       | 1 -
>  tools/perf/util/environment.c | 1 -
>  tools/perf/util/pager.c       | 5 -----
>  3 files changed, 7 deletions(-)
> 
> diff --git a/tools/perf/util/cache.h b/tools/perf/util/cache.h
> index fbcca21d66ab..c861373aaed3 100644
> --- a/tools/perf/util/cache.h
> +++ b/tools/perf/util/cache.h
> @@ -30,7 +30,6 @@ extern const char *perf_config_dirname(const char *, const char *);
>  
>  /* pager.c */
>  extern void setup_pager(void);
> -extern const char *pager_program;
>  extern int pager_in_use(void);
>  extern int pager_use_color;
>  
> diff --git a/tools/perf/util/environment.c b/tools/perf/util/environment.c
> index 275b0ee345f5..7405123692f1 100644
> --- a/tools/perf/util/environment.c
> +++ b/tools/perf/util/environment.c
> @@ -5,5 +5,4 @@
>   */
>  #include "cache.h"
>  
> -const char *pager_program;
>  int pager_use_color = 1;
> diff --git a/tools/perf/util/pager.c b/tools/perf/util/pager.c
> index 31ee02d4e988..53ef006a951c 100644
> --- a/tools/perf/util/pager.c
> +++ b/tools/perf/util/pager.c
> @@ -50,11 +50,6 @@ void setup_pager(void)
>  
>  	if (!isatty(1))
>  		return;
> -	if (!pager) {
> -		if (!pager_program)
> -			perf_config(perf_default_config, NULL);
> -		pager = pager_program;
> -	}
>  	if (!pager)
>  		pager = getenv("PAGER");
>  	if (!(pager || access("/usr/bin/pager", X_OK)))
> -- 
> 2.4.0