Re: [PATCH v3 07/15] lockdep: Implement crossrelease feature

From: Byungchul Park
Date: Tue Sep 13 2016 - 11:14:33 EST


On Tue, Sep 13, 2016 at 7:05 PM, Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote:
> On Tue, Sep 13, 2016 at 06:45:06PM +0900, Byungchul Park wrote:
>> Crossrelease feature calls a lock 'crosslock' if it is releasable
>> in any context. For crosslock, all locks having been held in the
>> release context of the crosslock, until eventually the crosslock
>> will be released, have dependency with the crosslock.
>>
>> Using crossrelease feature, we can detect deadlock possibility even
>> for lock_page(), wait_for_complete() and so on.
>>
>
> Completely inadequate.
>
> Please explain how cross-release does what it does. Talk about lock
> graphs and such.

Hello,

Could you tell me about what you intend, in detail?
I'm now asking you since I really don't know it.

The reason I reworked on documentation was to
answer your requests like "explain mathematically",
"tell how it works with graph" and so on. Should I
do anything else? I really don't know it.

If I missed something, please let me know. Then I
can do whatever you want if it's necessary.

> I do not have time to reverse engineer this stuff.

Why don't you read the document in the last patch
first? The document is my answer for your requests
you asked in version 1 thread. Insufficient?