[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] [PATCH v4 1/1] pci-host: add educational driver
From: |
Jiri Slaby |
Subject: |
Re: [Qemu-devel] [PATCH v4 1/1] pci-host: add educational driver |
Date: |
Wed, 21 Jan 2015 17:44:28 +0100 |
User-agent: |
Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.4.0 |
On 01/21/2015, 05:40 PM, Paolo Bonzini wrote:
>
>
> On 21/01/2015 17:28, Jiri Slaby wrote:
>> + if (atomic_fetch_or(&edu->status, EDU_STATUS_COMPUTING) &
>> EDU_STATUS_COMPUTING) {
>
> Theoretically the other thread could see EDU_STATUS_COMPUTING here and
> not enter the condvar wait. So...
>
>> + break;
>> + }
>> + qemu_mutex_lock(&edu->thr_mutex);
>> + edu->fact = val;
>> + qemu_cond_signal(&edu->thr_cond);
>> + qemu_mutex_unlock(&edu->thr_mutex);
>
> ... just one change:
>
> if (atomic_read(&edu->status) & EDU_STATUS_COMPUTING) {
> break;
> }
> /* EDU_STATUS_COMPUTING cannot go 0->1 concurrently, because
> * it is only set in this function and it is under the iothread
> * mutex.
> */
> qemu_mutex_lock(&edu->thr_mutex);
> edu->fact = val;
> atomic_or(&edu->status), EDU_STATUS_COMPUTING);
> qemu_cond_signal(&edu->thr_cond);
> qemu_mutex_unlock(&edu->thr_mutex);
>
> If you are okay with this change, I'll apply the patch to my tree.
Oh, I see. I will send v5 shortly as I found a bug in documentation too.
Thanks a lot for the review.
--
js
suse labs
- [Qemu-devel] [PATCH v4 1/1] pci-host: add educational driver, Jiri Slaby, 2015/01/21
- Re: [Qemu-devel] [PATCH v4 1/1] pci-host: add educational driver, Paolo Bonzini, 2015/01/21
- Re: [Qemu-devel] [PATCH v4 1/1] pci-host: add educational driver,
Jiri Slaby <=
- [Qemu-devel] [PATCH v5 1/1] hw: misc, add educational driver, Jiri Slaby, 2015/01/21
- Re: [Qemu-devel] [PATCH v5 1/1] hw: misc, add educational driver, Paolo Bonzini, 2015/01/21
- Re: [Qemu-devel] [PATCH v5 1/1] hw: misc, add educational driver, Eric Blake, 2015/01/21
- [Qemu-devel] [PATCH 1/1] edu: fix license information, Jiri Slaby, 2015/01/22
- Re: [Qemu-devel] [PATCH 1/1] edu: fix license information, Markus Armbruster, 2015/01/22
- Re: [Qemu-devel] [PATCH 1/1] edu: fix license information, Jiri Slaby, 2015/01/22
- Re: [Qemu-devel] [PATCH 1/1] edu: fix license information, Markus Armbruster, 2015/01/22
- Re: [Qemu-devel] [PATCH 1/1] edu: fix license information, Eric Blake, 2015/01/22
- Re: [Qemu-devel] [PATCH 1/1] edu: fix license information, Paolo Bonzini, 2015/01/22
- Re: [Qemu-devel] [PATCH 1/1] edu: fix license information, Jiri Slaby, 2015/01/22