Re: [PATCH v3 4/8] eal: change specific log levels at startup

[Olivier MATZ <olivier.matz@6wind.com>]

Hi Jianfeng,

On Fri, 14 Apr 2017 13:33:49 +0800, "Tan, Jianfeng" <jianfeng.tan@intel.com> wrote:
> Hi Olivier,
> 
> If I understand it correctly, this patch is to shift log level setting 
> earlier. But we did not remove the one in eal_parse_common_option(). So 
> we can see this parameter will be analyzed twice. Does it make sense to 
> remove analysis of log level in eal_parse_common_option()?
> 

The patch does not change the way the log level is parsed: it was
already parsed twice, because we want to know the log level as soon
as possible.

But the patch introduces a bug, as seen by Ferruh: the default log
level is not set properly when no --log-level parameter is passed.

Regards,
Olivier


> Thanks,
> Jianfeng
> 
> On 4/5/2017 12:40 AM, Olivier Matz wrote:
> > Example of use:
> >    ./app/test-pmd --log-level='pmd\.i40e.*,8'
> >
> >    This enables debug logs for all dynamic logs whose type starts with
> >    'pmd.i40e'.
> >
> > Signed-off-by: Olivier Matz <olivier.matz@6wind.com>
> > ---
> >   lib/librte_eal/bsdapp/eal/eal.c            |  4 +--
> >   lib/librte_eal/common/eal_common_options.c | 49 +++++++++++++++++++++++-------
> >   lib/librte_eal/linuxapp/eal/eal.c          |  4 +--
> >   3 files changed, 40 insertions(+), 17 deletions(-)
> >
> > diff --git a/lib/librte_eal/bsdapp/eal/eal.c b/lib/librte_eal/bsdapp/eal/eal.c
> > index 4ee9c66fe..fae6c7e0a 100644
> > --- a/lib/librte_eal/bsdapp/eal/eal.c
> > +++ b/lib/librte_eal/bsdapp/eal/eal.c
> > @@ -519,10 +519,8 @@ rte_eal_init(int argc, char **argv)
> >   
> >   	thread_id = pthread_self();
> >   
> > -	eal_log_level_parse(argc, argv);
> > -
> >   	/* set log level as early as possible */
> > -	rte_set_log_level(internal_config.log_level);
> > +	eal_log_level_parse(argc, argv);
> >   
> >   	if (rte_eal_cpu_init() < 0) {
> >   		rte_eal_init_alert("Cannot detect lcores.");
> > diff --git a/lib/librte_eal/common/eal_common_options.c b/lib/librte_eal/common/eal_common_options.c
> > index f36bc5568..606695a7f 100644
> > --- a/lib/librte_eal/common/eal_common_options.c
> > +++ b/lib/librte_eal/common/eal_common_options.c
> > @@ -739,25 +739,53 @@ eal_parse_syslog(const char *facility, struct internal_config *conf)
> >   }
> >   
> >   static int
> > -eal_parse_log_level(const char *level, uint32_t *log_level)
> > +eal_parse_log_level(const char *arg, struct internal_config *conf)
> >   {
> > -	char *end;
> > +	char *end, *str, *type, *level;
> >   	unsigned long tmp;
> >   
> > +	str = strdup(arg);
> > +	if (str == NULL)
> > +		return -1;
> > +
> > +	if (strchr(str, ',') == NULL) {
> > +		type = NULL;
> > +		level = str;
> > +	} else {
> > +		type = strsep(&str, ",");
> > +		level = strsep(&str, ",");
> > +	}
> > +
> >   	errno = 0;
> >   	tmp = strtoul(level, &end, 0);
> >   
> >   	/* check for errors */
> >   	if ((errno != 0) || (level[0] == '\0') ||
> > -	    end == NULL || (*end != '\0'))
> > -		return -1;
> > +		    end == NULL || (*end != '\0'))
> > +		goto fail;
> >   
> >   	/* log_level is a uint32_t */
> >   	if (tmp >= UINT32_MAX)
> > -		return -1;
> > +		goto fail;
> > +
> > +	printf("set log level %s,%lu\n",
> > +		type, tmp);
> > +
> > +	if (type == NULL) {
> > +		conf->log_level = tmp;
> > +		rte_set_log_level(tmp);
> > +	} else if (rte_log_set_level_regexp(type, tmp) < 0) {
> > +		printf("cannot set log level %s,%lu\n",
> > +			type, tmp);
> > +		goto fail;
> > +	}
> >   
> > -	*log_level = tmp;
> > +	free(str);
> >   	return 0;
> > +
> > +fail:
> > +	free(str);
> > +	return -1;
> >   }
> >   
> >   static enum rte_proc_type_t
> > @@ -898,15 +926,12 @@ eal_parse_common_option(int opt, const char *optarg,
> >   		break;
> >   
> >   	case OPT_LOG_LEVEL_NUM: {
> > -		uint32_t log;
> > -
> > -		if (eal_parse_log_level(optarg, &log) < 0) {
> > +		if (eal_parse_log_level(optarg, conf) < 0) {
> >   			RTE_LOG(ERR, EAL,
> >   				"invalid parameters for --"
> >   				OPT_LOG_LEVEL "\n");
> >   			return -1;
> >   		}
> > -		conf->log_level = log;
> >   		break;
> >   	}
> >   	case OPT_LCORES_NUM:
> > @@ -1057,7 +1082,9 @@ eal_common_usage(void)
> >   	       "  --"OPT_VMWARE_TSC_MAP"    Use VMware TSC map instead of native RDTSC\n"
> >   	       "  --"OPT_PROC_TYPE"         Type of this process (primary|secondary|auto)\n"
> >   	       "  --"OPT_SYSLOG"            Set syslog facility\n"
> > -	       "  --"OPT_LOG_LEVEL"         Set default log level\n"
> > +	       "  --"OPT_LOG_LEVEL"=<int>   Set global log level\n"
> > +	       "  --"OPT_LOG_LEVEL"=<type-regexp>,<int>\n"
> > +	       "                      Set specific log level\n"
> >   	       "  -v                  Display version information on startup\n"
> >   	       "  -h, --help          This help\n"
> >   	       "\nEAL options for DEBUG use only:\n"
> > diff --git a/lib/librte_eal/linuxapp/eal/eal.c b/lib/librte_eal/linuxapp/eal/eal.c
> > index f0ded185b..d98d56d2f 100644
> > --- a/lib/librte_eal/linuxapp/eal/eal.c
> > +++ b/lib/librte_eal/linuxapp/eal/eal.c
> > @@ -776,10 +776,8 @@ rte_eal_init(int argc, char **argv)
> >   
> >   	thread_id = pthread_self();
> >   
> > -	eal_log_level_parse(argc, argv);
> > -
> >   	/* set log level as early as possible */
> > -	rte_set_log_level(internal_config.log_level);
> > +	eal_log_level_parse(argc, argv);
> >   
> >   	if (rte_eal_cpu_init() < 0) {
> >   		rte_eal_init_alert("Cannot detect lcores.");  
>