Re: [Qemu-devel] [RFC PATCH 15/16] qcow2: Cancel COW when overwritten

[Kevin Wolf]

Am 18.09.2012 16:44, schrieb Paolo Bonzini:
> Il 18/09/2012 13:40, Kevin Wolf ha scritto:
>> +    qemu_co_mutex_unlock(&s->lock);
>> +    qemu_co_rwlock_wrlock(&m->l2_writeback_lock);
> 
> Can anybody else take the lock as reader again at this point?  If not, I
> wonder if this is more clear if you write it as a CoQueue.

This isn't "let one writer complete, then wake up n readers" (which
would indeed be represented more naturally as CoQueue), but rather "let
n readers complete, then wake up one writer".

Kevin