svn commit: r305722 - head/sys/x86/x86

[Sepherosa Ziehau]

On Mon, Sep 12, 2016 at 4:32 PM, Konstantin Belousov
<kostikbel at gmail.com> wrote:
> On Mon, Sep 12, 2016 at 04:57:58AM +0000, Sepherosa Ziehau wrote:
>> Author: sephe
>> Date: Mon Sep 12 04:57:58 2016
>> New Revision: 305722
>> URL: https://svnweb.freebsd.org/changeset/base/305722
>>
>> Log:
>>   x86: Use sx lock for interrupt sources.
>>
>>   - Certain pic_assign_cpu, e.g. msi_assign_cpu can have quite a long
>>     call chain.  For msi_assign_cpu, mutex makes complex PCI bridge
>>     drivers more tricky, e.g. sleep can note be called, etc, it will
>>     be pretty tricky for upcoming Hyper-V PCI bridge driver for PCI
>>     pass-through.
>
>>   - It is not used on any hot code path nor non-sleepable context, so
>>     sx should have the same effect as mutex.
> Did you tested ACPI_DMAR interrupt remapping mode with your patch and
> witness enabled ?

Nope, I am about to try it now.  BTW, I just checked the code for
ACPI_DMAR, I didn't see anything obviously w/ the lock type change
though.

Thanks,
sephe

-- 
Tomorrow Will Never Die