Re: [PATCH 1/2] tracing: Add .percent suffix option to histogram values

Re: [PATCH 1/2] tracing: Add .percent suffix option to histogram values

[kernel test robot]

Hi "Masami,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on rostedt-trace/for-next]
[also build test ERROR on linus/master v5.19 next-20220728]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Masami-Hiramatsu-Google/tracing-hist-Add-percentage-histogram-suffixes/20220801-110217
base:   https://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace.git for-next
config: i386-randconfig-a001-20220801 (https://download.01.org/0day-ci/archive/20220802/202208021438.2r5RXlo9-lkp@intel.com/config)
compiler: clang version 16.0.0 (https://github.com/llvm/llvm-project 52cd00cabf479aa7eb6dbb063b7ba41ea57bce9e)
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/intel-lab-lkp/linux/commit/aef5f602ee3aa9ca07402c1d3da0642e932c1b3a
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Masami-Hiramatsu-Google/tracing-hist-Add-percentage-histogram-suffixes/20220801-110217
        git checkout aef5f602ee3aa9ca07402c1d3da0642e932c1b3a
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=i386 SHELL=/bin/bash

If you fix the issue, kindly add following tag where applicable
Reported-by: kernel test robot <lkp@intel.com>

All errors (new ones prefixed by >>):

>> ld.lld: error: undefined symbol: __udivdi3
   >>> referenced by trace_events_hist.c:5211 (kernel/trace/trace_events_hist.c:5211)
   >>>               trace/trace_events_hist.o:(hist_show) in archive kernel/built-in.a
   >>> referenced by trace_events_hist.c:0 (kernel/trace/trace_events_hist.c:0)
   >>>               trace/trace_events_hist.o:(hist_show) in archive kernel/built-in.a
   >>> referenced by trace_events_hist.c:5211 (kernel/trace/trace_events_hist.c:5211)
   >>>               trace/trace_events_hist.o:(hist_show) in archive kernel/built-in.a
   >>> referenced 1 more times

-- 
0-DAY CI Kernel Test Service
https://01.org/lkp

Re: [PATCH 1/2] tracing: Add .percent suffix option to histogram values

[Steven Rostedt]

On Tue, 2 Aug 2022 14:49:36 +0800
kernel test robot <lkp@intel.com> wrote:

> All errors (new ones prefixed by >>):
> 
> >> ld.lld: error: undefined symbol: __udivdi3  

This is due to this:

> @@ -5190,18 +5202,34 @@ static void hist_trigger_print_key(struct seq_file *m,
>  	seq_puts(m, "}");
>  }
>  
> +/* Get the 100 times of the percentage of @val in @total */
> +static inline unsigned int __get_percentage(u64 val, u64 total)
> +{
> +	if (val < (U64_MAX / 10000))
> +		return (unsigned int)(val * 10000 / total);
> +	else
> +		return val / (total / 10000);
> +}
> +

You can't use '/' on u64 values. You have to use div64*(). Otherwise 32 bit
architectures may use floating point operations or glibc helpers.

See the other divisions in trace_events_hist.c that do so too.

-- Steve


>    >>> referenced by trace_events_hist.c:5211 (kernel/trace/trace_events_hist.c:5211)
>    >>>               trace/trace_events_hist.o:(hist_show) in archive kernel/built-in.a
>    >>> referenced by trace_events_hist.c:0 (kernel/trace/trace_events_hist.c:0)
>    >>>               trace/trace_events_hist.o:(hist_show) in archive kernel/built-in.a
>    >>> referenced by trace_events_hist.c:5211 (kernel/trace/trace_events_hist.c:5211)
>    >>>               trace/trace_events_hist.o:(hist_show) in archive kernel/built-in.a
>    >>> referenced 1 more times  

Re: [PATCH 1/2] tracing: Add .percent suffix option to histogram values

[Masami Hiramatsu]

On Tue, 2 Aug 2022 10:56:46 -0400
Steven Rostedt <rostedt@goodmis.org> wrote:

> On Tue, 2 Aug 2022 14:49:36 +0800
> kernel test robot <lkp@intel.com> wrote:
> 
> > All errors (new ones prefixed by >>):
> > 
> > >> ld.lld: error: undefined symbol: __udivdi3  
> 
> This is due to this:
> 
> > @@ -5190,18 +5202,34 @@ static void hist_trigger_print_key(struct seq_file *m,
> >  	seq_puts(m, "}");
> >  }
> >  
> > +/* Get the 100 times of the percentage of @val in @total */
> > +static inline unsigned int __get_percentage(u64 val, u64 total)
> > +{
> > +	if (val < (U64_MAX / 10000))
> > +		return (unsigned int)(val * 10000 / total);
> > +	else
> > +		return val / (total / 10000);
> > +}
> > +
> 
> You can't use '/' on u64 values. You have to use div64*(). Otherwise 32 bit
> architectures may use floating point operations or glibc helpers.

Yeah, I forgot that. And also I have to check "total != 0" here. 

> 
> See the other divisions in trace_events_hist.c that do so too.

Thanks!

> 
> -- Steve
> 
> 
> >    >>> referenced by trace_events_hist.c:5211 (kernel/trace/trace_events_hist.c:5211)
> >    >>>               trace/trace_events_hist.o:(hist_show) in archive kernel/built-in.a
> >    >>> referenced by trace_events_hist.c:0 (kernel/trace/trace_events_hist.c:0)
> >    >>>               trace/trace_events_hist.o:(hist_show) in archive kernel/built-in.a
> >    >>> referenced by trace_events_hist.c:5211 (kernel/trace/trace_events_hist.c:5211)
> >    >>>               trace/trace_events_hist.o:(hist_show) in archive kernel/built-in.a
> >    >>> referenced 1 more times  
> 


-- 
Masami Hiramatsu (Google) <mhiramat@kernel.org>