Re: [RFA] Don't use thread_db on corefiles

Michael Snyder
2001-12-13T23:47:44Z

Daniel Jacobowitz wrote:
>
> On Thu, Dec 13, 2001 at 03:04:07PM -0800, Michael Snyder wrote:
> > OK. I'd like to see that patch when it's ready.
> > Do you use only lwp's, or do you use glibc/libpthread threads?
> > If you use library threads, are you saving their info in the
> > core file, or are you only saving the info for the lwp's?
>
> It's completely thread-package-agnostic. I dump all LWPs sharing the
> same VM, as a fairly reliable marker (I'd use 2.4 threadgroups, but
> LinuxThreads doesn't use them...)

Good, dumping only the LWPs is the right thing to do, I think.
But if that's what you're doing, then the thread-db module should
still be useful to you: I know it is on Solaris, which this one
was modelled after. You'll need it if-and-when the thread-to-lwp
mapping ever becomes many-to-one (which may be soon).

> So there is enough information there for lin-lwp to parse the threads,
> if we stubbed out its attempts to write, I expect. But since the
> current Linux threads model has one thread per process, I can simply
> use the corefile.c thread support instead, which I'd rather do.

You can't rely on that assumption in the future. We need to make
all these packages work together. It won't be a freebie, it will
require some work. But as I say, it works for Solaris gdb. We
just didn't bother making it work for Linux gdb and corefiles,
because up until now there were no threads in corefiles on Linux.

Michael