Re: [PATCH 0/6] Support kernel-backed user threads on FreeBSD

John Baldwin
2016-01-12T18:55:44Z

On Monday, January 11, 2016 10:53:50 AM John Baldwin wrote:
> This set of patches adds support for examining kernel-backed user threads on
> FreeBSD. There is more history in a comment in fbsd-nat.c, but this target
> uses ptrace directly (instead of libthread_db) to support the current
> threading library (libthr) on FreeBSD which uses a kernel thread for each
> user thread. Support for thread names in both core dumps (via FreeBSD's
> OS-specific NT_THRMISC core note) and live is supported as is scheduler
> locking. gcore generates register notes for each thread as well.
>
> The first two patches are to binutils to support FreeBSD-specific core
> notes. The last four are to GDB.

(Apologies for fubar'ing the threading on the patches in this series.)

One other note I forgot to mention is that currently I leave the ptid for
single-threaded processes as (pid, 0, 0) (i.e. I only use LWPs in PTIDs
when there is more than one thread). What is the best practice? Should
I always use LWPs in ptids instead?

--
John Baldwin