From: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
To: kvm-ia64@vger.kernel.org
Subject: Re: [PATCH 2/3] KVM: Centralize slots_lock aquisition during KVM_CREATE_IRQCHIP
Date: Thu, 16 Dec 2010 09:47:34 +0000 [thread overview]
Message-ID: <4D09E036.2090705@oss.ntt.co.jp> (raw)
In-Reply-To: <20101216014326.9210211a.takuya.yoshikawa@gmail.com>
(2010/12/16 18:34), Avi Kivity wrote:
>>> Maybe we ought to move slots_lock acquisition to kvm_io_bus_register() and friends.
>>>
>>
>>
>> So it will move the lock acquisition to the opposite ( callee ) side than mine.
>> At first, I tried to do that, but there are so many ...
>>
>> Anyway, your suggestion seems to be the best way if possible.
>>
>>
>> One question: how about kvm_io_bus_[read|write] ?
>>
>> These are called from the emulator but I could not find where slots_lock
>> are held though I can see the comments
>>
>> "kvm_io_bus_[read|write] - called under kvm->slots_lock"
>>
>
> They're under srcu now, the comments are outdated.
>
> We used to have slots_lock be a rwsem, taken for read or write as necessary. Now we use srcu for read, and the slots_lock mutex + synchronize_srcu for write.
>
Ah, would you mind updating the comments?
- or just removing outdated ones?
I will reread these locking based on your answer!
Thanks,
Takuya
WARNING: multiple messages have this Message-ID (diff)
From: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
To: Avi Kivity <avi@redhat.com>
Cc: Takuya Yoshikawa <takuya.yoshikawa@gmail.com>,
mtosatti@redhat.com, kvm@vger.kernel.org,
kvm-ia64@vger.kernel.org
Subject: Re: [PATCH 2/3] KVM: Centralize slots_lock aquisition during KVM_CREATE_IRQCHIP
Date: Thu, 16 Dec 2010 18:47:34 +0900 [thread overview]
Message-ID: <4D09E036.2090705@oss.ntt.co.jp> (raw)
In-Reply-To: <4D09DD3F.5070408@redhat.com>
(2010/12/16 18:34), Avi Kivity wrote:
>>> Maybe we ought to move slots_lock acquisition to kvm_io_bus_register() and friends.
>>>
>>
>>
>> So it will move the lock acquisition to the opposite ( callee ) side than mine.
>> At first, I tried to do that, but there are so many ...
>>
>> Anyway, your suggestion seems to be the best way if possible.
>>
>>
>> One question: how about kvm_io_bus_[read|write] ?
>>
>> These are called from the emulator but I could not find where slots_lock
>> are held though I can see the comments
>>
>> "kvm_io_bus_[read|write] - called under kvm->slots_lock"
>>
>
> They're under srcu now, the comments are outdated.
>
> We used to have slots_lock be a rwsem, taken for read or write as necessary. Now we use srcu for read, and the slots_lock mutex + synchronize_srcu for write.
>
Ah, would you mind updating the comments?
- or just removing outdated ones?
I will reread these locking based on your answer!
Thanks,
Takuya
next prev parent reply other threads:[~2010-12-16 9:47 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-12-15 16:43 [PATCH 2/3] KVM: Centralize slots_lock aquisition during Takuya Yoshikawa
2010-12-15 16:43 ` [PATCH 2/3] KVM: Centralize slots_lock aquisition during KVM_CREATE_IRQCHIP Takuya Yoshikawa
2010-12-16 9:11 ` Avi Kivity
2010-12-16 9:11 ` Avi Kivity
2010-12-16 9:29 ` Takuya Yoshikawa
2010-12-16 9:29 ` Takuya Yoshikawa
2010-12-16 9:34 ` Avi Kivity
2010-12-16 9:34 ` Avi Kivity
2010-12-16 9:47 ` Takuya Yoshikawa [this message]
2010-12-16 9:47 ` Takuya Yoshikawa
2010-12-16 9:55 ` Avi Kivity
2010-12-16 9:55 ` Avi Kivity
2010-12-16 12:51 ` [PATCH 2/3] KVM: Centralize slots_lock aquisition during Takuya Yoshikawa
2010-12-16 12:51 ` [PATCH 2/3] KVM: Centralize slots_lock aquisition during KVM_CREATE_IRQCHIP Takuya Yoshikawa
-- strict thread matches above, loose matches on Subject: below --
2010-12-15 16:45 [PATCH 3/3] KVM: Centralize irq_lock aquisition during Takuya Yoshikawa
2010-12-15 16:45 ` [PATCH 3/3] KVM: Centralize irq_lock aquisition during KVM_CREATE_IRQCHIP Takuya Yoshikawa
2010-12-15 16:41 [PATCH 1/3] KVM: Take missing slots_lock for Takuya Yoshikawa
2010-12-15 16:41 ` [PATCH 1/3] KVM: Take missing slots_lock for kvm_io_bus_unregister_dev() Takuya Yoshikawa
2010-12-16 9:12 ` Avi Kivity
2010-12-16 9:12 ` Avi Kivity
2010-12-15 16:39 [PATCH-v2 0/3] KVM: Take missing slots_lock for Takuya Yoshikawa
2010-12-15 16:39 ` [PATCH-v2 0/3] KVM: Take missing slots_lock for kvm_io_bus_unregister_dev() Takuya Yoshikawa
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=4D09E036.2090705@oss.ntt.co.jp \
--to=yoshikawa.takuya@oss.ntt.co.jp \
--cc=kvm-ia64@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.