[U-Boot] [PATCH 03/33] log: Allow #define LOG_DEBUG to enable logging in a file

[Bin Meng]

Hi Simon,

On Tue, Jan 22, 2019 at 9:14 AM Simon Glass <sjg at chromium.org> wrote:
>
> At present it is possible to '#define DEBUG' at the top of a file which
> causes all debug() statements in that file to become active. There is
> currently no equivalent with logging, but this is a useful function.
>
> Add a LOG_DEBUG define along with documentation.
>
> Signed-off-by: Simon Glass <sjg at chromium.org>
> ---
>
>  doc/README.log | 14 ++++++++++++++
>  include/log.h  |  7 ++++++-
>  2 files changed, 20 insertions(+), 1 deletion(-)
>
> diff --git a/doc/README.log b/doc/README.log
> index 96bc9523ef..f8922af764 100644
> --- a/doc/README.log
> +++ b/doc/README.log
> @@ -69,6 +69,20 @@ If CONFIG_LOG is not set, then no logging will be available.
>  The above have SPL versions also, e.g. CONFIG_SPL_MAX_LOG_LEVEL.
>
>
> +Temporary logging within a single file
> +--------------------------------------
> +
> +Sometimes it is useful to turn on logging just in one file. You can use this:
> +
> +   #define LOG_DEBUG
> +
> +to enable building in of all logging statements in a single file. Put it at
> +the top of the file, before any #includes.
> +
> +To actually get U-Boot to output this you need to also set the default logging
> +level - e.g. set CONFIG_LOG_DEFAULT_LEVEL to 7 or more.

Why should CONFIG_LOG_DEFAULT_LEVEL be 7 or more?

> +
> +
>  Convenience functions
>  ---------------------
>
> diff --git a/include/log.h b/include/log.h
> index d7f6471006..acf2a14b91 100644
> --- a/include/log.h
> +++ b/include/log.h
> @@ -111,11 +111,16 @@ int _log(enum log_category_t cat, enum log_level_t level, const char *file,
>  #endif
>
>  #if CONFIG_IS_ENABLED(LOG)
> +#ifdef LOG_DEBUG
> +#define _LOG_DEBUG     1
> +#else
> +#define _LOG_DEBUG     0
> +#endif
>
>  /* Emit a log record if the level is less that the maximum */
>  #define log(_cat, _level, _fmt, _args...) ({ \
>         int _l = _level; \
> -       if (CONFIG_IS_ENABLED(LOG) && _l <= _LOG_MAX_LEVEL) \
> +       if (CONFIG_IS_ENABLED(LOG) && (_l <= _LOG_MAX_LEVEL || _LOG_DEBUG)) \
>                 _log((enum log_category_t)(_cat), _l, __FILE__, __LINE__, \
>                       __func__, \
>                       pr_fmt(_fmt), ##_args); \
> --

Regards,
Bin