svn commit: r241889 - in user/andre/tcp_workqueue/sys: arm/arm cddl/compat/opensolaris/kern cddl/contrib/opensolaris/uts/common/dtrace cddl/contrib/opensolaris/uts/common/fs/zfs ddb dev/acpica dev/...

[Attilio Rao]

On Sun, Oct 28, 2012 at 9:20 PM, Andre Oppermann <andre at freebsd.org> wrote:
> On 28.10.2012 18:42, Attilio Rao wrote:
>>
>> On Sat, Oct 27, 2012 at 5:27 PM, Attilio Rao <attilio at freebsd.org> wrote:
>>>
>>> Here we go with further comments tweaks.
>>> Also, in order to make it a complete NOP from KPI perspective I had to
>>> change the way the mtx_assert() wrapper was implemented as in v1 it
>>> wasn't correctly handling the const qualifier.
>>> I think the result is better now and you should refer to this patch for
>>> reviews:
>>> http://www.freebsd.org/~attilio/mtx_decoupled2.patch
>
>
> Thank you for the updated patch.  If the others more versed in this
> area are happy with it I'm not objecting.
>
>
>> BTW, the mtx_sysuninit() introduction can be avoided by using this other
>> trick:
>> #define MTX_SYSINIT(name, mtx, desc, opts)                              \
>>          static struct mtx_args name##_args = {                          \
>>                  (mtx),                                                  \
>>                  (desc),                                                 \
>>                  (opts)                                                  \
>>          };                                                              \
>>          SYSINIT(name##_mtx_sysinit, SI_SUB_LOCK, SI_ORDER_MIDDLE,       \
>>              mtx_sysinit, &name##_args);                                 \
>>          SYSUNINIT(name##_mtx_sysuninit, SI_SUB_LOCK, SI_ORDER_MIDDLE,   \
>>              _mtx_destroy, __DEVOLATILE(void *, &(mtx)->mtx_lock))
>>
>> I'm just not sure that I would like the use of __DEVOLATILE() even if
>> it would help in this case when introducing MTX_SYSINIT_UNSHARE()
>> because we will just need to reuse the same code.
>
>
> I'm not really happy about the _unshare naming.  Something like
> _aligned or _cachline would be much more obvious on what it does.

I agree. Infact if we want to apply this to ie. sx locks too _unshared
will generate too much confusion (as already reported by Jeff too).
I'd say _aligned is good to go.

Thanks,
Attilio


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