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

From: Jin, Yao
Date: Wed Jun 12 2019 - 08:58:43 EST

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:


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 {
s64 wdiff;
+ 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;


Hi Jiri,

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


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


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


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


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.

Jin Yao