Re: [PATCH v2 3/5] perf report: Sort by sampled cycles percent per block for stdio

[Jin, Yao]

On 10/16/2019 6:15 PM, Jiri Olsa wrote:
> On Tue, Oct 15, 2019 at 10:53:18PM +0800, Jin, Yao wrote:
>
> SNIP
>
> > > > +static struct block_header_column{
> > > > +	const char *name;
> > > > +	int width;
> > > > +} block_columns[PERF_HPP_REPORT__BLOCK_MAX_INDEX] = {
> > > > +	[PERF_HPP_REPORT__BLOCK_TOTAL_CYCLES_COV] = {
> > > > +		.name = "Sampled Cycles%",
> > > > +		.width = 15,
> > > > +	},
> > > > +	[PERF_HPP_REPORT__BLOCK_LBR_CYCLES] = {
> > > > +		.name = "Sampled Cycles",
> > > > +		.width = 14,
> > > > +	},
> > > > +	[PERF_HPP_REPORT__BLOCK_CYCLES_PCT] = {
> > > > +		.name = "Avg Cycles%",
> > > > +		.width = 11,
> > > > +	},
> > > > +	[PERF_HPP_REPORT__BLOCK_AVG_CYCLES] = {
> > > > +		.name = "Avg Cycles",
> > > > +		.width = 10,
> > > > +	},
> > > > +	[PERF_HPP_REPORT__BLOCK_RANGE] = {
> > > > +		.name = "[Program Block Range]",
> > > > +		.width = 70,
> > > > +	},
> > > > +	[PERF_HPP_REPORT__BLOCK_DSO] = {
> > > > +		.name = "Shared Object",
> > > > +		.width = 20,
> > > > +	}
> > > >    };
> > >
> > > so we already have support for multiple columns,
> > > why don't you add those as 'struct sort_entry' objects?
> >
> > For 'struct sort_entry' objects, do you mean I should reuse the "sort_dso"
> > which has been implemented yet in util/sort.c?
> >
> > For other columns, it looks we can't reuse the existing sort_entry objects.
>
> I did not mean reuse, just add new sort entries
> to current sort framework

Does it seem like what the c2c does?

For example, my new update is like:

struct block_dimension {
       const char              *header;
       int                     idx;
       int                     width;
       struct sort_entry       *se;
       int64_t (*cmp)(struct perf_hpp_fmt *,
                      struct hist_entry *, struct hist_entry *);
       int64_t (*sort)(struct perf_hpp_fmt *,
                       struct hist_entry *, struct hist_entry *);
       int   (*entry)(struct perf_hpp_fmt *, struct perf_hpp *,
                      struct hist_entry *);
};

struct block_fmt {
       struct perf_hpp_fmt     fmt;
       struct report           *rep;
       struct block_dimension  *dim;
};

static struct block_dimension dim_total_cycles_pct {
       .header = "Sampled Cycles%",
       .idx = PERF_HPP_REPORT__BLOCK_TOTAL_CYCLES_PCT,
       .width = 15,
       .cmp = block_info__cmp;
       .sort = block_cycles_cov_sort;
       .entry = block_cycles_cov_entry;
};

......

Is above new update correct?

> > > SNIP
> > >
> > > > +{
> > > > +	struct block_hist *bh = &rep->block_hist;
> > > > +
> > > > +	get_block_hists(hists, bh, rep);
> > > > +	symbol_conf.report_individual_block = true;
> > > > +	hists__fprintf(&bh->block_hists, true, 0, 0, 0,
> > > > +		       stdout, true);
> > > > +	hists__delete_entries(&bh->block_hists);
> > > > +	return 0;
> > > > +}
> > > > +
> > > >    static int perf_evlist__tty_browse_hists(struct evlist *evlist,
> > > >    					 struct report *rep,
> > > >    					 const char *help)
> > > > @@ -500,6 +900,12 @@ static int perf_evlist__tty_browse_hists(struct evlist *evlist,
> > > >    			continue;
> > > >    		hists__fprintf_nr_sample_events(hists, rep, evname, stdout);
> > > > +
> > > > +		if (rep->total_cycles) {
> > > > +			hists__fprintf_all_blocks(hists, rep);
> > >
> > > so this call kicks all the block info setup/count/print, right?
> >
> > Yes, all in this call.
> >
> > > I thingk it shouldn't be in the output code, but in the code before..
> > > from what I see you could count block_info counts during the sample
> > > processing, no?
> >
> > In sample processing, we just get all symbols and account the cycles per
> > symbol. We need to create/count the block_info at some points after the
> > sample processing.
>
> understand, but it needs to be outside display function

OK, I will move the code for block_info collection outside of display 
function.

> also, can't you gather the block_info data gradually
> during the sample processing?

Looks we have to gather the block_info after the sample processing. 
That's because in each sample processing, we will call 
hist__account_cycles(). Then finally __symbol__account_cycles() gets 
called for accounting one basic block in this symbol.

ch[offset].num_aggr++;
ch[offset].cycles_aggr += cycles;

So actually, after the sample processing, we will get the num_aggr and 
cycles_aggr for this basic block and compute the average cycles for this 
block (cycles_aggr / num_aggr).

That's why I think we should gather the block_info after the sample 
processing.

Thanks
Jin Yao

> jirka
>
> > Maybe it's not very good to put block info setup/count/print in a call, but
> > it's really not easy to process the block_info during the sample processing.
> >
> > Thanks
> > Jin Yao
> >
> > > jirka