Re: [dpdk-dev] [PATCH] eal:Fix log messages always being printed from rte_eal_cpu_init

[Bruce Richardson <bruce.richardson@intel.com>]

On Sat, Jun 06, 2015 at 07:04:05PM -0500, Keith Wiles wrote:
> The RTE_LOG(DEBUG, ...) messages in rte_eal_cpu_init() are printed
> even when the log level on the command line was set to INFO or lower.
> 
> The problem is the rte_eal_cpu_init() routine was called before
> the command line args are scanned. Setting --log-level=7 now
> correctly does not print the messages from the rte_eal_cpu_init() routine.
> 
> Signed-off-by: Keith Wiles <keith.wiles@intel.com>

This seems a good idea - make it easy to reduce the verbosity on startup if
so desired. Some comments below.

> ---
>  lib/librte_eal/bsdapp/eal/eal.c   | 43 ++++++++++++++++++++++++++++++++++-----
>  lib/librte_eal/linuxapp/eal/eal.c | 43 ++++++++++++++++++++++++++++++++++-----
>  2 files changed, 76 insertions(+), 10 deletions(-)
> 
> diff --git a/lib/librte_eal/bsdapp/eal/eal.c b/lib/librte_eal/bsdapp/eal/eal.c
> index 43e8a47..ca10f2c 100644
> --- a/lib/librte_eal/bsdapp/eal/eal.c
> +++ b/lib/librte_eal/bsdapp/eal/eal.c
> @@ -306,6 +306,38 @@ eal_get_hugepage_mem_size(void)
>  	return (size < SIZE_MAX) ? (size_t)(size) : SIZE_MAX;
>  }
>  
> +/* Parse the arguments for --log-level only */
> +static void
> +eal_log_level_parse(int argc, char **argv)
> +{
> +	int opt;
> +	char **argvopt;
> +	int option_index;
> +
> +	argvopt = argv;
> +
> +	eal_reset_internal_config(&internal_config);
> +
> +	while ((opt = getopt_long(argc, argvopt, eal_short_options,
> +				  eal_long_options, &option_index)) != EOF) {
> +
> +		int ret;
> +
> +		/* getopt is not happy, stop right now */
> +		if (opt == '?')
> +			break;
> +
> +		ret = (opt == OPT_LOG_LEVEL_NUM)?
> +			eal_parse_common_option(opt, optarg, &internal_config) : 0;
> +
> +		/* common parser is not happy */
> +		if (ret < 0)
> +			break;
> +	}
> +
> +	optind = 0; /* reset getopt lib */
> +}
> +
>  /* Parse the argument given in the command line of the application */
>  static int
>  eal_parse_args(int argc, char **argv)
> @@ -317,8 +349,6 @@ eal_parse_args(int argc, char **argv)
>  
>  	argvopt = argv;
>  
> -	eal_reset_internal_config(&internal_config);
> -
>  	while ((opt = getopt_long(argc, argvopt, eal_short_options,
>  				  eal_long_options, &option_index)) != EOF) {
>  
> @@ -447,6 +477,12 @@ rte_eal_init(int argc, char **argv)
>  	if (rte_eal_log_early_init() < 0)
>  		rte_panic("Cannot init early logs\n");
>  
> +	eal_log_level_parse(argc, argv);
> +
> +	/* set log level as early as possible */
> +	rte_set_log_level(internal_config.log_level);
> +
> +	RTE_LOG(INFO, EAL,  "DPDK Version %s\n", rte_version());

There is already the -v option to the EAL to print the DPDK version. Just add
that flag to any command, as it has no other effects. I don't think we need to
increase the verbosity of startup by always printing it.

>  	if (rte_eal_cpu_init() < 0)
>  		rte_panic("Cannot detect lcores\n");
>  
> @@ -454,9 +490,6 @@ rte_eal_init(int argc, char **argv)
>  	if (fctret < 0)
>  		exit(1);
>  
> -	/* set log level as early as possible */
> -	rte_set_log_level(internal_config.log_level);
> -
>  	if (internal_config.no_hugetlbfs == 0 &&
>  			internal_config.process_type != RTE_PROC_SECONDARY &&
>  			eal_hugepage_info_init() < 0)
> diff --git a/lib/librte_eal/linuxapp/eal/eal.c b/lib/librte_eal/linuxapp/eal/eal.c
> index bd770cf..090ec99 100644
> --- a/lib/librte_eal/linuxapp/eal/eal.c
> +++ b/lib/librte_eal/linuxapp/eal/eal.c
> @@ -499,6 +499,38 @@ eal_get_hugepage_mem_size(void)
>  	return (size < SIZE_MAX) ? (size_t)(size) : SIZE_MAX;
>  }
>  
> +/* Parse the arguments for --log-level only */
> +static void
> +eal_log_level_parse(int argc, char **argv)
> +{
> +	int opt;
> +	char **argvopt;
> +	int option_index;
> +
> +	argvopt = argv;
> +
> +	eal_reset_internal_config(&internal_config);
> +
> +	while ((opt = getopt_long(argc, argvopt, eal_short_options,
> +				  eal_long_options, &option_index)) != EOF) {
> +
> +		int ret;
> +
> +		/* getopt is not happy, stop right now */
> +		if (opt == '?')
> +			break;
> +
> +		ret = (opt == OPT_LOG_LEVEL_NUM)?
> +			eal_parse_common_option(opt, optarg, &internal_config) : 0;
> +
> +		/* common parser is not happy */
> +		if (ret < 0)
> +			break;
> +	}
> +
> +	optind = 0; /* reset getopt lib */
> +}
> +

This function looks duplicated for linux and bsd. Can we move it to one of the
common files instead?

Regards,
/Bruce