svn commit: r184558 - head/sys/dev/acpica/Osd

[Alexander Motin]

Jung-uk Kim wrote:
> On Sunday 02 November 2008 07:50 am, Alexander Motin wrote:
>> Author: mav
>> Date: Sun Nov  2 12:50:16 2008
>> New Revision: 184558
>> URL: http://svn.freebsd.org/changeset/base/184558
>>
>> Log:
>>   As soon as we have several threads per process now, it is not
>> correct to use process ID as ACPI thread ID. Concurrent requests
>> with equal thread IDs broke ACPI mutexes operation causing
>> unpredictable errors including AE_AML_MUTEX_NOT_ACQUIRED that I
>> have seen.
>>
>>   Use kernel thread ID instead of process ID for ACPI thread.
> 
> Sorry but this patch is incorrect, i.e., td_tid is not unique.  You 
> have to use curthread or (p_pid, td_tid) pair.  Unfortunately, even 
> if you correct this problem, you also have to correct ACPI_THREAD_ID 
> definition, which is in the vendor code.  That's why it wasn't done 
> yet and it is more complicated than you think, i.e., ACPI-CA assumes 
> sizeof(ACPI_THREAD_ID) == sizeof(int), etc.  Please see the related 
> ACPI-CA bugs:

I'm also sorry, but that is what I see:
typedef __int32_t       __lwpid_t;      /* Thread ID (a.k.a. LWP) */
...
td->td_tid = alloc_unr(tid_unrhdr);
...
tid_unrhdr = new_unrhdr(PID_MAX + 2, INT_MAX, &tid_lock);

So what have I missed, where is the problem? Why td_tid is not unique
and where is the size problem?

-- 
Alexander Motin