[PATCH] Improve performance of IO locks

[Thomas Fitzsimmons]

Hi Wilco,

Wilco Dijkstra <Wilco.Dijkstra@arm.com> writes:

>>> I looked at elf/unload as an example; it's segfaulting in
>>> _dl_relocate_object, backtrace attached; not sure what else to check.
>>
>> I don't see this on powerpc64, with a toolchain based on GCC 8.2 and
>> binutils 2.30.  I'm at a loss how these things could be related.
>
> I would not expect the dynamic linker to have changed at all, so one
> option is to check the binary is identical before/after my commit. If
> the dynamic linker somehow got some uses of SINGLE_THREAD_P then that
> might access TLS before it is setup.

elf/ld64.so.1 is identical before and after your change.

> The other possibility is that the binary it is trying to link has
> corrupted relocations.  It's hard to imagine how that could happen
> unless you use the new GLIBC to link an application and fileio fails
> to write out the data for the relocations.

I don't know how to check this.  I'll contact you off-list to set up
temporary remote access for you.

Thomas