Re: [PATCH 39/79] libperf: Add perf_evlist__add function

[Arnaldo Carvalho de Melo]

Em Sun, Jul 21, 2019 at 01:24:26PM +0200, Jiri Olsa escreveu:
> Adding perf_evlist__add function to add perf_evsel
> in perf_evlist struct.
> 
> Link: http://lkml.kernel.org/n/tip-pnfovrqcgxquioroelzfzb57@xxxxxxxxxxxxxx
> Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
> ---
>  tools/perf/lib/evlist.c              | 7 +++++++
>  tools/perf/lib/include/perf/evlist.h | 3 +++
>  tools/perf/lib/libperf.map           | 1 +
>  tools/perf/util/evlist.c             | 2 +-
>  4 files changed, 12 insertions(+), 1 deletion(-)
> 
> diff --git a/tools/perf/lib/evlist.c b/tools/perf/lib/evlist.c
> index fdc8c1894b37..e5f187fa4e57 100644
> --- a/tools/perf/lib/evlist.c
> +++ b/tools/perf/lib/evlist.c
> @@ -2,8 +2,15 @@
>  #include <perf/evlist.h>
>  #include <linux/list.h>
>  #include <internal/evlist.h>
> +#include <internal/evsel.h>
>  
>  void perf_evlist__init(struct perf_evlist *evlist)
>  {
>  	INIT_LIST_HEAD(&evlist->entries);
>  }
> +
> +void perf_evlist__add(struct perf_evlist *evlist,
> +		      struct perf_evsel *evsel)
> +{
> +	list_add_tail(&evsel->node, &evlist->entries);
> +}
> diff --git a/tools/perf/lib/include/perf/evlist.h b/tools/perf/lib/include/perf/evlist.h
> index 1ddfcca0bd01..6992568b14a0 100644
> --- a/tools/perf/lib/include/perf/evlist.h
> +++ b/tools/perf/lib/include/perf/evlist.h
> @@ -5,7 +5,10 @@
>  #include <perf/core.h>
>  
>  struct perf_evlist;
> +struct perf_evsel;
>  
>  LIBPERF_API void perf_evlist__init(struct perf_evlist *evlist);
> +LIBPERF_API void perf_evlist__add(struct perf_evlist *evlist,
> +				  struct perf_evsel *evsel);
>  
>  #endif /* __LIBPERF_EVLIST_H */
> diff --git a/tools/perf/lib/libperf.map b/tools/perf/lib/libperf.map
> index 5ca6ff6fcdfa..06ccf31eb24d 100644
> --- a/tools/perf/lib/libperf.map
> +++ b/tools/perf/lib/libperf.map
> @@ -11,6 +11,7 @@ LIBPERF_0.0.1 {
>  		perf_thread_map__put;
>  		perf_evsel__init;
>  		perf_evlist__init;
> +		perf_evlist__add;
>  	local:
>  		*;
>  };
> diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c
> index aacddd9b2d64..ea25c7b49a4c 100644
> --- a/tools/perf/util/evlist.c
> +++ b/tools/perf/util/evlist.c
> @@ -180,8 +180,8 @@ static void perf_evlist__propagate_maps(struct evlist *evlist)
>  
>  void evlist__add(struct evlist *evlist, struct evsel *entry)
>  {
> +	perf_evlist__add(&evlist->core, &entry->core);
>  	entry->evlist = evlist;
> -	list_add_tail(&entry->core.node, &evlist->core.entries);
>  	entry->idx = evlist->nr_entries;
>  	entry->tracking = !entry->idx;

Right after applying this patch my alias for building perf crashes:

I.e. I have:

alias m='perf stat -e cycles:u,instructions:u make -k O=/tmp/build/perf  -C tools/perf install-bin'

And I'm applyin your series patch by patch, it stopped working when I
tried to build the next patch in this series, as the previous one caused
the segfault below, investigating...

(gdb) run stat sleep 1
Starting program: /root/bin/perf stat sleep 1
Missing separate debuginfos, use: dnf debuginfo-install glibc-2.29-15.fc30.x86_64
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib64/libthread_db.so.1".

Program received signal SIGSEGV, Segmentation fault.
0x00000000004f6b55 in __perf_evlist__propagate_maps (evlist=0xbb34c0, evsel=0x0) at util/evlist.c:161
161		if (!evsel->own_cpus || evlist->has_user_cpus) {
Missing separate debuginfos, use: dnf debuginfo-install bzip2-libs-1.0.6-29.fc30.x86_64 elfutils-libelf-0.176-3.fc30.x86_64 elfutils-libs-0.176-3.fc30.x86_64 glib2-2.60.4-1.fc30.x86_64 libbabeltrace-1.5.6-2.fc30.x86_64 libgcc-9.1.1-1.fc30.x86_64 libunwind-1.3.1-2.fc30.x86_64 libuuid-2.33.2-1.fc30.x86_64 libxcrypt-4.4.6-2.fc30.x86_64 libzstd-1.4.0-1.fc30.x86_64 numactl-libs-2.0.12-2.fc30.x86_64 pcre-8.43-2.fc30.x86_64 perl-libs-5.28.2-436.fc30.x86_64 popt-1.16-17.fc30.x86_64 python2-libs-2.7.16-2.fc30.x86_64 slang-2.3.2-5.fc30.x86_64 xz-libs-5.2.4-5.fc30.x86_64 zlib-1.2.11-15.fc30.x86_64
(gdb) p evsel
$1 = (struct evsel *) 0x0
(gdb) p evlist
$2 = (struct evlist *) 0xbb34c0
(gdb) bt
#0  0x00000000004f6b55 in __perf_evlist__propagate_maps (evlist=0xbb34c0, evsel=0x0) at util/evlist.c:161
#1  0x00000000004f6c7a in perf_evlist__propagate_maps (evlist=0xbb34c0) at util/evlist.c:178
#2  0x00000000004f955e in perf_evlist__set_maps (evlist=0xbb34c0, cpus=0x0, threads=0x0) at util/evlist.c:1128
#3  0x00000000004f66f8 in evlist__init (evlist=0xbb34c0, cpus=0x0, threads=0x0) at util/evlist.c:52
#4  0x00000000004f6790 in evlist__new () at util/evlist.c:64
#5  0x0000000000456071 in cmd_stat (argc=3, argv=0x7fffffffd670) at builtin-stat.c:1705
#6  0x00000000004dd0fa in run_builtin (p=0xa21e00 <commands+288>, argc=3, argv=0x7fffffffd670) at perf.c:304
#7  0x00000000004dd367 in handle_internal_command (argc=3, argv=0x7fffffffd670) at perf.c:356
#8  0x00000000004dd4ae in run_argv (argcp=0x7fffffffd4cc, argv=0x7fffffffd4c0) at perf.c:400
#9  0x00000000004dd81a in main (argc=3, argv=0x7fffffffd670) at perf.c:522
(gdb)