Em Fri, Jun 16, 2017 at 01:06:52PM -0300, Arnaldo Carvalho de Melo escreveu: > Em Fri, Jun 02, 2017 at 12:25:08PM -0300, Arnaldo Carvalho de Melo escreveu: > > Em Fri, Jun 02, 2017 at 04:37:53PM +0200, Milian Wolff escreveu: > > > The PC returned by dwfl_frame_pc may map into a not-yet-reported > > > module. We have to report it before we continue unwinding. But when > > > we query for the isactivation flag in dwfl_frame_pc, libdw will > > > actually do one more unwinding step internally which can then break > > > and lead to missed frames or broken stacks. > > > > > > With libunwind we get e.g.: > > > > Jiri, can you review this one? > > ping
Sorry, saw yesterday's replies now, will apply the patch with an Acked-by: Jan. Thanks, - Arnaldo > > Thanks, > > > > - Arnaldo > > > > > ~~~~~ > > > heaptrack_gui 2228 135073.400474: 613969 cycles: > > > 108c8e [unknown] (/usr/lib/libQt5Core.so.5.8.0) > > > 1093bc [unknown] (/usr/lib/libQt5Core.so.5.8.0) > > > 109e7b QLocale::QLocale (/usr/lib/libQt5Core.so.5.8.0) > > > 1470ff [unknown] (/usr/lib/libQt5Core.so.5.8.0) > > > 147f67 QSystemLocale::query (/usr/lib/libQt5Core.so.5.8.0) > > > 109fbf QLocalePrivate::updateSystemPrivate > > > (/usr/lib/libQt5Core.so.5.8.0) > > > 10aa27 QLocale::QLocale (/usr/lib/libQt5Core.so.5.8.0) > > > 1e02c3 [unknown] (/usr/lib/libQt5Core.so.5.8.0) > > > 2113bb [unknown] (/usr/lib/libQt5Core.so.5.8.0) > > > 211505 [unknown] (/usr/lib/libQt5Core.so.5.8.0) > > > 1b5df0 QFileInfo::exists (/usr/lib/libQt5Core.so.5.8.0) > > > 92eb2 [unknown] (/usr/lib/libQt5Core.so.5.8.0) > > > 93423 [unknown] (/usr/lib/libQt5Core.so.5.8.0) > > > 93d2a QLibraryInfo::location (/usr/lib/libQt5Core.so.5.8.0) > > > 2170af [unknown] (/usr/lib/libQt5Core.so.5.8.0) > > > 297c53 QCoreApplicationPrivate::init > > > (/usr/lib/libQt5Core.so.5.8.0) > > > f7cde QGuiApplicationPrivate::init > > > (/usr/lib/libQt5Gui.so.5.8.0) > > > 1589e8 QApplicationPrivate::init > > > (/usr/lib/libQt5Widgets.so.5.8.0) > > > 78622 main > > > (/home/milian/projects/compiled/other/bin/heaptrack_gui) > > > 20439 __libc_start_main (/usr/lib/libc-2.25.so) > > > 78299 _start > > > (/home/milian/projects/compiled/other/bin/heaptrack_gui) > > > > > > heaptrack_gui 2228 135073.401156: 569521 cycles: > > > 131633 QString::endsWith (/usr/lib/libQt5Core.so.5.8.0) > > > 1a0701 QDir::cleanPath (/usr/lib/libQt5Core.so.5.8.0) > > > 21b82d [unknown] (/usr/lib/libQt5Core.so.5.8.0) > > > 1b3727 QFileInfo::canonicalFilePath > > > (/usr/lib/libQt5Core.so.5.8.0) > > > 2780c7 QFactoryLoader::update (/usr/lib/libQt5Core.so.5.8.0) > > > 279525 QFactoryLoader::QFactoryLoader > > > (/usr/lib/libQt5Core.so.5.8.0) > > > e5bd0 QPlatformIntegrationFactory::create > > > (/usr/lib/libQt5Gui.so.5.8.0) > > > f5a1c QGuiApplicationPrivate::createPlatformIntegration > > > (/usr/lib/libQt5Gui.so.5.8.0) > > > f650c QGuiApplicationPrivate::createEventDispatcher > > > (/usr/lib/libQt5Gui.so.5.8.0) > > > 298524 QCoreApplicationPrivate::init > > > (/usr/lib/libQt5Core.so.5.8.0) > > > f7cde QGuiApplicationPrivate::init > > > (/usr/lib/libQt5Gui.so.5.8.0) > > > 1589e8 QApplicationPrivate::init > > > (/usr/lib/libQt5Widgets.so.5.8.0) > > > 78622 main > > > (/home/milian/projects/compiled/other/bin/heaptrack_gui) > > > 20439 __libc_start_main (/usr/lib/libc-2.25.so) > > > 78299 _start > > > (/home/milian/projects/compiled/other/bin/heaptrack_gui) > > > ~~~~~ > > > > > > Note the two frames 1589e8 and 78622 in the first sample. These are > > > missing when unwinding with libdw. The second sample's breakage is > > > more obvious: > > > > > > ~~~~~ > > > heaptrack_gui 2228 135073.400474: 613969 cycles: > > > 108c8e [unknown] (/usr/lib/libQt5Core.so.5.8.0) > > > 1093bc [unknown] (/usr/lib/libQt5Core.so.5.8.0) > > > 109e7b QLocale::QLocale (/usr/lib/libQt5Core.so.5.8.0) > > > 1470ff [unknown] (/usr/lib/libQt5Core.so.5.8.0) > > > 147f67 QSystemLocale::query (/usr/lib/libQt5Core.so.5.8.0) > > > 109fbf QLocalePrivate::updateSystemPrivate > > > (/usr/lib/libQt5Core.so.5.8.0) > > > 10aa27 QLocale::QLocale (/usr/lib/libQt5Core.so.5.8.0) > > > 1e02c3 [unknown] (/usr/lib/libQt5Core.so.5.8.0) > > > 2113bb [unknown] (/usr/lib/libQt5Core.so.5.8.0) > > > 211505 [unknown] (/usr/lib/libQt5Core.so.5.8.0) > > > 1b5df0 QFileInfo::exists (/usr/lib/libQt5Core.so.5.8.0) > > > 92eb2 [unknown] (/usr/lib/libQt5Core.so.5.8.0) > > > 93423 [unknown] (/usr/lib/libQt5Core.so.5.8.0) > > > 93d2a QLibraryInfo::location (/usr/lib/libQt5Core.so.5.8.0) > > > 2170af [unknown] (/usr/lib/libQt5Core.so.5.8.0) > > > 297c53 QCoreApplicationPrivate::init > > > (/usr/lib/libQt5Core.so.5.8.0) > > > f7cde QGuiApplicationPrivate::init > > > (/usr/lib/libQt5Gui.so.5.8.0) > > > 20439 __libc_start_main (/usr/lib/libc-2.25.so) > > > 78299 _start > > > (/home/milian/projects/compiled/other/bin/heaptrack_gui) > > > > > > heaptrack_gui 2228 135073.401156: 569521 cycles: > > > 131633 QString::endsWith (/usr/lib/libQt5Core.so.5.8.0) > > > 1a0701 QDir::cleanPath (/usr/lib/libQt5Core.so.5.8.0) > > > 21b82d [unknown] (/usr/lib/libQt5Core.so.5.8.0) > > > 1b3727 QFileInfo::canonicalFilePath > > > (/usr/lib/libQt5Core.so.5.8.0) > > > 2780c7 QFactoryLoader::update (/usr/lib/libQt5Core.so.5.8.0) > > > 279525 QFactoryLoader::QFactoryLoader > > > (/usr/lib/libQt5Core.so.5.8.0) > > > e5bd0 QPlatformIntegrationFactory::create > > > (/usr/lib/libQt5Gui.so.5.8.0) > > > 723dbf [unknown] ([unknown]) > > > ~~~~~ > > > > > > This patch fixes this issue and the libdw unwinder mimicks the > > > libunwind behavior more closely. > > > > > > Cc: Arnaldo Carvalho de Melo <[email protected]> > > > Cc: Namhyung Kim <[email protected]> > > > Cc: Jiri Olsa <[email protected]> > > > Signed-off-by: Milian Wolff <[email protected]> > > > --- > > > tools/perf/util/unwind-libdw.c | 8 ++++++++ > > > 1 file changed, 8 insertions(+) > > > > > > diff --git a/tools/perf/util/unwind-libdw.c > > > b/tools/perf/util/unwind-libdw.c > > > index da45c4be5fb3..7755a5e0fe5e 100644 > > > --- a/tools/perf/util/unwind-libdw.c > > > +++ b/tools/perf/util/unwind-libdw.c > > > @@ -178,6 +178,14 @@ frame_callback(Dwfl_Frame *state, void *arg) > > > Dwarf_Addr pc; > > > bool isactivation; > > > > > > + if (!dwfl_frame_pc(state, &pc, NULL)) { > > > + pr_err("%s", dwfl_errmsg(-1)); > > > + return DWARF_CB_ABORT; > > > + } > > > + > > > + // report the module before we query for isactivation > > > + report_module(pc, ui); > > > + > > > if (!dwfl_frame_pc(state, &pc, &isactivation)) { > > > pr_err("%s", dwfl_errmsg(-1)); > > > return DWARF_CB_ABORT; > > > -- > > > 2.13.0 > > -- > > To unsubscribe from this list: send the line "unsubscribe linux-perf-users" > > in > > the body of a message to [email protected] > > More majordomo info at http://vger.kernel.org/majordomo-info.html
