Messages in this thread | | | Date | Mon, 7 Aug 2023 16:03:43 +0200 | From | Artem Savkov <> | Subject | Re: [PATCH 1/1] Revert "perf report: Append inlines to non-DWARF callchains" |
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On Mon, Aug 07, 2023 at 10:34:44AM -0300, Arnaldo Carvalho de Melo wrote: > Em Mon, Aug 07, 2023 at 01:00:08PM +0200, Artem Savkov escreveu: > > On Wed, Aug 02, 2023 at 09:43:40AM +0200, Artem Savkov wrote: > > > Hi Arnaldo, > > > > > > On Tue, Aug 01, 2023 at 06:42:47PM -0300, Arnaldo Carvalho de Melo wrote: > > > > Hi Artem, > > > > > > > > Can you please double check this? I reproduced with: > > > > > > > > git checkout 46d21ec067490ab9cdcc89b9de5aae28786a8b8e > > > > build it > > > > perf record -a -g sleep 5s > > > > perf report > > > > > > > > Do you get the same slowness and then reverting it, i.e. just > > > > going to HEAD~ and rebuilding getting a fast 'perf report' startup, i.e. > > > > without the inlines in the callchains? > > > > > > With a simple test like this I definitely get a slowdown, but not sure > > > if it can be called excessive. > > > > > > Below are the times I got by running 'time perf report' and hitting 'q' > > > during load so that it quits as soon as it is loads up. Tested on a > > > freshly updated fedora 38. > > > > My bad, I had wrong debuginfo installed for the kernel I tested. I can > > reproduce it with the correct one. Looks like vmlinux is just too much > > for addr2line. Maybe we can skip it but leave other inlines in, like so: > > That is a possibilit, and probably we could make it cheaper by looking > at the cpumode, avoiding calling addr2line when we didn't makage to > resolve the symbol, etc. > > We also may want to have this as an option that has to be explicitely > enabled, like --resolve-inlines, as this will add overhead no matter if > we stop calling addr2line and do it more efficiently, etc.
Sounds good, I'll look into it.
> Fact is, we're late in the 6.5 schedule, so the best thing now is to > just revert the patch and then try again later, ok?
Yes, sure.
> - Arnaldo > > > diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c > > index 11de3ca8d4fa7..fef309cd401f7 100644 > > --- a/tools/perf/util/machine.c > > +++ b/tools/perf/util/machine.c > > @@ -2388,7 +2388,9 @@ static int add_callchain_ip(struct thread *thread, > > ms.map = map__get(al.map); > > ms.sym = al.sym; > > > > - if (!branch && append_inlines(cursor, &ms, ip) == 0) > > + if (!branch && ms.map && ms.map->dso && > > + strcmp(ms.map->dso->short_name, "[kernel.vmlinux]") && > > + append_inlines(cursor, &ms, ip) == 0) > > goto out; > > > > srcline = callchain_srcline(&ms, al.addr); > > > > > > - Arnaldo > > > > > > > > ---- > > > > > > > > This reverts commit 46d21ec067490ab9cdcc89b9de5aae28786a8b8e. > > > > > > > > The tests were made with a specific workload, further tests on a > > > > recently updated fedora 38 system with a system wide perf.data file > > > > shows 'perf report' taking excessive time, so lets revert this until a > > > > full investigation and improvement on the addr2line support code is > > > > made. > > > > > > > > Cc: Andrii Nakryiko <andrii.nakryiko@gmail.com> > > > > Cc: Artem Savkov <asavkov@redhat.com> > > > > Cc: Namhyung Kim <namhyung@kernel.org> > > > > Cc: Adrian Hunter <adrian.hunter@intel.com> > > > > Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> > > > > Cc: Ian Rogers <irogers@google.com> > > > > Cc: Ingo Molnar <mingo@redhat.com> > > > > Cc: Jiri Olsa <jolsa@kernel.org> > > > > Cc: Mark Rutland <mark.rutland@arm.com> > > > > Cc: Masami Hiramatsu <mhiramat@kernel.org> > > > > Cc: Milian Wolff <milian.wolff@kdab.com> > > > > Cc: Peter Zijlstra <peterz@infradead.org> > > > > Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> > > > > --- > > > > tools/perf/util/machine.c | 5 ----- > > > > 1 file changed, 5 deletions(-) > > > > > > > > diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c > > > > index 4e62843d51b7dbf9..f4cb41ee23cdbcfc 100644 > > > > --- a/tools/perf/util/machine.c > > > > +++ b/tools/perf/util/machine.c > > > > @@ -45,7 +45,6 @@ > > > > > > > > static void __machine__remove_thread(struct machine *machine, struct thread_rb_node *nd, > > > > struct thread *th, bool lock); > > > > -static int append_inlines(struct callchain_cursor *cursor, struct map_symbol *ms, u64 ip); > > > > > > > > static struct dso *machine__kernel_dso(struct machine *machine) > > > > { > > > > @@ -2385,10 +2384,6 @@ static int add_callchain_ip(struct thread *thread, > > > > ms.maps = maps__get(al.maps); > > > > ms.map = map__get(al.map); > > > > ms.sym = al.sym; > > > > - > > > > - if (!branch && append_inlines(cursor, &ms, ip) == 0) > > > > - goto out; > > > > - > > > > srcline = callchain_srcline(&ms, al.addr); > > > > err = callchain_cursor_append(cursor, ip, &ms, > > > > branch, flags, nr_loop_iter, > > > > -- > > > > 2.41.0 > > > > > > > > > > -- > > > Artem > > > > -- > > Artem > > > > -- > > - Arnaldo >
-- Artem
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