On Wed, 2017-12-06 at 13:00 +0000, Silva João wrote: > From info task, all tasks are in "Runnable" state. There are 39 in this list. > > From gdb the program seems blocked reading a file (libc read()). If you have 39 tasks in Runnable state, I guess that they are not all blocked in libc read ? So, you might investigate which task(s) are really still doing something by doing e.g. thread apply all bt and/or put breakpoints at places that you know should be soon encountered by the runnable tasks and continue the execution. And then control-c, and redo the above to see if some tasks are/have still progressed.
Also, from gdb, you can do monitor v.info scheduler to have the valgrind status of the tasks/threads. You can also use the option --trace-sched=yes to see how and if valgrind still schedules the threads. Note that at my work, we are using valgrind + Ada tasks without any particular problem. > > But when I list (l) in gdb it does not show the correct line. It seems the > synchronization with the source file is not correct. > > > As you are using Ada/SPARK, I guess you use a special tasking profile > > (e.g. ravenscar or similar). I have no idea how such tasking profile > > interacts with the single thread at a time model of Valgrind. > > > > You might try --fair-sched=yes to see if that helps. > > I tried but without success. > > > Also, try also --tool=none, just to see if the problem/blockage status > > is linked to memcheck, or to the valgrind scheduling and Ada/SPARK > > interaction. > > With nulgrind it still "hangs" so I seems related to the tread issue you > mention. Possibly also, the change in the way the threads are scheduled causes an application deadlock. You might thus also try --tool=helgrind just in case this would reveal some non thread safe bug ... Philippe ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ Valgrind-users mailing list Valgrind-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/valgrind-users
