On Tue, Jan 28, 2003 at 12:27:03PM -0500, Robert Love wrote:
> On Tue, 2003-01-28 at 10:45, Daniel Jacobowitz wrote:
>
> > I think this isn't an issue; multi-threaded core dumps are done by
> > the core_waiter synchronization, so all other threads will have exited
> > before the first thread to crash actually writes out its core.
>
> I think the problem is the filenames need to not overwrite each other -
> not actual synchronization in the kernel (which, as you point out, is
> correct).
>
> If we name the coredumps based on ->tgid, then all threads will dump to
> the same file. If we use ->pid, each thread will use its unique PID as
> its filename.
That wasn't my point. All of the other threads have already terminated
without dumping core at tis point; I don't think it's possible for two
threads of a CLONE_THREAD application to both dump core. See
fs/exec.c:coredump_wait.
Also, once one thread gets into do_coredump it clears mm->dumpable;
nothing else will dump core from that MM anyway.
I think using ->tgid is a good idea.
-- Daniel Jacobowitz MontaVista Software Debian GNU/Linux Developer - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
This archive was generated by hypermail 2b29 : Fri Jan 31 2003 - 22:00:20 EST