Re: [PATCH v2 4/7] perf diff: Use hists to manage basic blocks per symbol

[Jin, Yao]

On 6/12/2019 3:44 PM, Jiri Olsa wrote:
On Wed, Jun 12, 2019 at 02:11:44PM +0800, Jin, Yao wrote:


On 6/11/2019 4:56 PM, Jiri Olsa wrote:
On Sat, Jun 08, 2019 at 07:41:47PM +0800, Jin, Yao wrote:


On 6/5/2019 7:44 PM, Jiri Olsa wrote:
On Mon, Jun 03, 2019 at 10:36:14PM +0800, Jin Yao wrote:

SNIP

diff --git a/tools/perf/util/sort.h b/tools/perf/util/sort.h
index 43623fa..d1641da 100644
--- a/tools/perf/util/sort.h
+++ b/tools/perf/util/sort.h
@@ -79,6 +79,9 @@ struct hist_entry_diff {
                /* HISTC_WEIGHTED_DIFF */
                s64     wdiff;
+
+               /* PERF_HPP_DIFF__CYCLES */
+               s64     cycles;
        };
    };
@@ -143,6 +146,9 @@ struct hist_entry {
        struct branch_info      *branch_info;
        long                    time;
        struct hists            *hists;
+       void                    *block_hists;
+       int                     block_idx;
+       int                     block_num;
        struct mem_info         *mem_info;
        struct block_info       *block_info;

could you please not add the new block* stuff in here,
and instead use the "c2c model" and use yourr own struct
on top of hist_entry? we are trying to librarize this
stuff and keep only necessary things in here..

you're already using hist_entry_ops, so should be easy

something like:

        struct block_hist_entry {
                void                    *block_hists;
                int                     block_idx;
                int                     block_num;
                struct block_info       *block_info;

                struct hist_entry       he;
        };



jirka


Hi Jiri,

After more considerations, maybe I can't move these stuffs from hist_entry
to block_hist_entry.

why?


Actually we use 2 kinds of hist_entry in this patch series. On kind of
hist_entry is for symbol/function. The other kind of hist_entry is for basic
block.

correct

so the way I see it the processing goes like this:


1) there's standard hist_entry processing ending up
     with evsel->hists->rb_root full of hist entries

2) then you process every hist_entry and create
     new 'struct hists' for each and fill it with
     symbol counts data



you could add 'struct hist_entry_ops' for the 1) processing
that adds the 'struct hists' object for each hist_entry

and add another 'struct hist_entry_ops' for 2) processing
to carry the block data for each hist_entry

jirka


Hi Jiri,

Yes, I can use two hist_entry_ops but one thing is still difficult to handle
that is the printing of blocks.

One function may contain multiple blocks so I add 'block_num' in 'struct
hist_entry' to record the number of blocks.

In patch "perf diff: Print the basic block cycles diff", I reuse most of
current code to print the blocks. The major change is:

  static int hist_entry__fprintf(struct hist_entry *he, size_t size,
                                char *bf, size_t bfsz, FILE *fp,
                                bool ignore_callchains) {

+       if (he->block_hists)
+               return hist_entry__block_fprintf(he, bf, size, fp);
+


you could do it the way we do hierarchy and have
something like 'symbol_conf.report_block'

         if (symbol_conf.report_hierarchy)
                 return hist_entry__hierarchy_fprintf(he, &hpp, hists, fp);

and in hist_entry__block_fprintf you cast the hist_entry
to your struct.. so you'll have all the data

jirka


Thanks Jiri. So it looks I need to define 'struct block_hist_entry' in 
util/sort.h, then hist_entry__block_fprintf can know this struct. 
Previously I just defined this struct in builtin-diff.c.

Thanks
Jin Yao