[m-rev.] for-review: Apply upstream BoehmGC changes for glibc lock elision bug workaround

[Paul Bone]

On Fri, Sep 19, 2014 at 10:15:41AM +1000, Julien Fischer wrote:
>
> On Thu, 18 Sep 2014, Paul Bone wrote:
>
>> For review/testing by others.
>>
>> Last time I modified something in boehm_gc/ I broke the build for OS X.
>> This works on 64bit Linux (Debian testing) but I havn't tested it on other
>> platforms.  Julien could you help me out by building this on OS X and
>> perhaps Windows?  I've been testing it with the icfp2000_par_pbone benchmark
>> in asm_fast.gc.par.stseg.  Thanks.
>>
>> I have a branch with these patches here:
>> https://github.com/PaulBone/mercury/tree/fix_tsx_bug
>
> Ok, I'll take a look at it on those systems, but probably not today.
> (The above benchmark won't work on OS X in any case.)
>

Thanks.

Yeah, I'm not too worried about the benchmark.  Besides, only linux +
specific intel processors + specific microcode versions will have the
original bug.

Intel found a bug in their TSX implementation and released microcode to
disable the feature completely.  I don't know if the Intel bug is the cause
of my problems or not, I'll ask Andi, he might know.

Cheers.


-- 
Paul Bone