Re: [PATCH v6] perf stat: Fix wrong skipping for per-die aggregation

[Jin, Yao]

Hi Arnaldo, Jiri,

On 1/16/2021 4:31 AM, Arnaldo Carvalho de Melo wrote:
> Em Fri, Jan 15, 2021 at 05:28:14PM -0300, Arnaldo Carvalho de Melo escreveu:
> > Em Thu, Jan 14, 2021 at 08:00:32PM +0100, Jiri Olsa escreveu:
> > > On Thu, Jan 14, 2021 at 09:27:55AM +0800, Jin Yao wrote:
> > >
> > > SNIP
> > >
> > > >       2.003776312 S1-D0           1             855616 Bytes llc_misses.mem_read
> > > >       2.003776312 S1-D1           1             949376 Bytes llc_misses.mem_read
> > > >       3.006512788 S0-D0           1            1338880 Bytes llc_misses.mem_read
> > > >       3.006512788 S0-D1           1             920064 Bytes llc_misses.mem_read
> > > >       3.006512788 S1-D0           1             877184 Bytes llc_misses.mem_read
> > > >       3.006512788 S1-D1           1            1020736 Bytes llc_misses.mem_read
> > > >       4.008895291 S0-D0           1             926592 Bytes llc_misses.mem_read
> > > >       4.008895291 S0-D1           1             906368 Bytes llc_misses.mem_read
> > > >       4.008895291 S1-D0           1             892224 Bytes llc_misses.mem_read
> > > >       4.008895291 S1-D1           1             987712 Bytes llc_misses.mem_read
> > > >       5.001590993 S0-D0           1             962624 Bytes llc_misses.mem_read
> > > >       5.001590993 S0-D1           1             912512 Bytes llc_misses.mem_read
> > > >       5.001590993 S1-D0           1             891200 Bytes llc_misses.mem_read
> > > >       5.001590993 S1-D1           1             978432 Bytes llc_misses.mem_read
> > > >
> > > > On no-die system, die_id is 0, actually it's hashmap(socket,0), original behavior
> > > > is not changed.
> > > >
> > > > Reported-by: Huang Ying <ying.huang@xxxxxxxxx>
> > > > Signed-off-by: Jin Yao <yao.jin@xxxxxxxxxxxxxxx>
> > > > ---
> > > > v6:
> > > >   Fix the perf test python failure by adding hashmap.c to python-ext-sources.
> > > >
> > > >   root@kbl-ppc:~# ./perf test python
> > > >   19: 'import perf' in python                                         : Ok
> > >
> > > Acked-by: Jiri Olsa <jolsa@xxxxxxxxxx>
> >
> > Jin, this is breaking the build in some 32-bit system, can you please
> > take a look to validate these warnings?
>
> One such system:
>
>    28    13.75 debian:experimental-x-mipsel  : FAIL mipsel-linux-gnu-gcc (Debian 10.2.1-3) 10.2.1 20201224
>
>   
> >    CC       /tmp/build/perf/util/srcline.o
> > util/stat.c: In function 'pkg_id_hash':
> > util/stat.c:285:9: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast]
> >    return (int64_t)key & 0xffffffff;
> >           ^
> > util/stat.c: In function 'pkg_id_equal':
> > util/stat.c:291:9: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast]
> >    return (int64_t)key1 == (int64_t)key2;
> >           ^
> > util/stat.c:291:26: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast]
> >    return (int64_t)key1 == (int64_t)key2;
> >                            ^
> > util/stat.c: In function 'check_per_pkg':
> > util/stat.c:342:26: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]
> >    if (hashmap__find(mask, (void *)key, NULL))
> >                            ^
> > util/stat.c:345:28: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]
> >     ret = hashmap__add(mask, (void *)key, (void *)1);
> >                              ^
> >    CC       /tmp/build/perf/tests/expand-cgroup.o

Thanks for reporting this build issue on 32 bit system.

In v7, I use size_t to replace uint64_t and change the hash key to 'die_id << 16 | socket_id'. I 
assume that 16 bits is enough for socket id, is it true? But if it's not true, we have to use a more 
complicated way such as allocate a structure which has die_id and socket_id and add it to hashmap.

But I'm not sure if that's necessary because I can't imagine a system which has socket id > 65535.

Thanks
Jin Yao