[Valgrind-users] Thread names in valgrind and vgdb

[Matthias S. <zz...@ge...>]

Hi!

I wonder if it would be good to have valgrind remember the names of the 
threads.
Our application sets the name of the threads using

pthread_setname_np and that is implemented by calling the syscall 
prctl(PR_SET_NAME).

Using plain gdb, info threads also lists these user-defined names.
But valgrind and gdb+vgdb only show the thread-ids.


The only place in valgrind that already handles thread names is a 
helgrind client request.


I think it would be a good idea if valgrind could also show the thread name.
My first attempt is to add more code to POST(sys_prctl) and in case of 
VKI_PR_SET_NAME is called, store the set name into a new field of 
ThreadState.
Then in every user visible place where a threadid is printed, also print 
the name.
How could this look like?


==123== Thread 5 (MyThread1):

==123== Invalid read of size 1:
...

I will send a patch once this is done.


The other option would be to call prctl(PR_GET_NAME) at every place that 
needs a thread name.


Regards
Matthias