From: Sasha Levin <levinsasha928@gmail.com>
To: Ingo Molnar <mingo@elte.hu>
Cc: Pekka Enberg <penberg@kernel.org>,
kvm@vger.kernel.org, asias.hejun@gmail.com, gorcunov@gmail.com,
prasadjoshi124@gmail.com,
"Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Subject: Re: [PATCH v2 6/8] kvm tools: Add rwlock wrapper
Date: Mon, 30 May 2011 13:05:34 +0300 [thread overview]
Message-ID: <1306749934.14564.71.camel@lappy> (raw)
In-Reply-To: <20110530095645.GC8461@elte.hu>
On Mon, 2011-05-30 at 11:56 +0200, Ingo Molnar wrote:
> * Sasha Levin <levinsasha928@gmail.com> wrote:
>
> > I'm just saying that we're limited to as many VCPU threads as we
> > can create. br_read_lock() won't do anything on a non-VCPU thread,
> > which makes it impossible to test it on non-VCPUs.
>
> btw., i wondered about that limit - don't we want to fix it?
>
> I mean, there's no fundamental reason why brlocks should do 'nothing'
> in worker threads. In fact it's a subtle breakage waiting AFAICS.
>
Can they do anything useful without locking? I think we should work on
integrating an RCU and changing brlocks to use that instead of focusing
too much on the current implementation.
This will also fix that limit you don't like :)
> We should have enumeration for all threads that kvm starts, and that
> we can use for a generic pause/resume facility. Can you see anything
> that prevents that model?
>
Theres a difference between how you would pause a VCPU thread as opposed
to a non-VCPU thread, other than that - no. We could use a thread
manager.
> Thanks,
>
> Ingo
--
Sasha.
next prev parent reply other threads:[~2011-05-30 10:06 UTC|newest]
Thread overview: 72+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-05-30 8:30 [PATCH v2 1/8] kvm tools: Use correct value for user signal base Sasha Levin
2011-05-30 8:30 ` [PATCH v2 2/8] kvm tools: Remove wrong global definition of kvm Sasha Levin
2011-05-30 8:38 ` Ingo Molnar
2011-05-30 8:59 ` Sasha Levin
2011-05-30 8:30 ` [PATCH v2 3/8] kvm tools: Allow pausing guests Sasha Levin
2011-05-30 8:39 ` Ingo Molnar
2011-05-30 8:30 ` [PATCH v2 4/8] kvm tools: Pause/resume guest using SIGUSR2 Sasha Levin
2011-05-30 8:41 ` Ingo Molnar
2011-05-30 8:30 ` [PATCH v2 5/8] kvm tools: Add a brlock Sasha Levin
2011-05-30 8:30 ` [PATCH v2 6/8] kvm tools: Add rwlock wrapper Sasha Levin
2011-05-30 8:43 ` Ingo Molnar
2011-05-30 9:29 ` Pekka Enberg
2011-05-30 9:34 ` Sasha Levin
2011-05-30 9:40 ` Pekka Enberg
2011-05-30 9:46 ` Sasha Levin
2011-05-30 9:48 ` Pekka Enberg
2011-05-30 9:54 ` Ingo Molnar
2011-05-30 11:11 ` Takuya Yoshikawa
2011-05-30 11:12 ` Sasha Levin
2011-05-30 11:26 ` Takuya Yoshikawa
2011-05-30 11:39 ` Avi Kivity
2011-05-30 11:49 ` Ingo Molnar
2011-05-30 11:55 ` Pekka Enberg
2011-05-30 11:58 ` Sasha Levin
2011-05-30 12:20 ` Ingo Molnar
2011-05-30 12:22 ` Sasha Levin
2011-05-30 12:25 ` Avi Kivity
2011-05-30 12:23 ` Avi Kivity
2011-05-30 12:30 ` Pekka Enberg
2011-05-30 12:32 ` Avi Kivity
2011-05-30 14:10 ` Ingo Molnar
2011-05-30 14:30 ` Avi Kivity
2011-05-30 14:43 ` Ingo Molnar
2011-05-30 14:50 ` Avi Kivity
2011-05-30 19:32 ` Ingo Molnar
2011-05-30 12:04 ` Avi Kivity
2011-05-30 12:36 ` Ingo Molnar
2011-05-30 12:44 ` Avi Kivity
2011-05-30 12:46 ` Pekka Enberg
2011-05-30 12:48 ` Avi Kivity
2011-05-30 13:05 ` Sasha Levin
2011-06-03 7:27 ` Sasha Levin
2011-06-03 7:34 ` Ingo Molnar
2011-06-03 7:54 ` Sasha Levin
2011-06-03 19:31 ` Paul E. McKenney
2011-06-03 19:56 ` Sasha Levin
2011-06-03 20:22 ` Paul E. McKenney
2011-06-03 21:03 ` Sasha Levin
2011-06-03 21:20 ` Paul E. McKenney
2011-06-03 22:54 ` Sasha Levin
2011-06-03 23:05 ` Paul E. McKenney
2011-06-04 6:26 ` Sasha Levin
2011-06-04 16:30 ` Paul E. McKenney
2011-06-14 22:26 ` Sasha Levin
2011-06-14 23:42 ` Paul E. McKenney
2011-06-15 1:25 ` Sasha Levin
2011-06-15 4:22 ` Paul E. McKenney
2011-06-05 12:12 ` Avi Kivity
2011-05-30 14:16 ` Takuya Yoshikawa
2011-05-30 9:56 ` Ingo Molnar
2011-05-30 10:05 ` Sasha Levin [this message]
2011-05-30 10:13 ` Ingo Molnar
2011-05-30 10:22 ` Sasha Levin
2011-05-30 10:30 ` Ingo Molnar
2011-05-30 10:41 ` Sasha Levin
2011-05-30 8:30 ` [PATCH v2 7/8] kvm tools: Add debug mode to brlock Sasha Levin
2011-05-30 8:30 ` [PATCH v2 8/8] kvm tools: Use brlock in MMIO and IOPORT Sasha Levin
2011-05-30 8:47 ` Ingo Molnar
2011-05-30 8:56 ` Sasha Levin
2011-05-30 8:35 ` [PATCH v2 1/8] kvm tools: Use correct value for user signal base Ingo Molnar
2011-05-30 8:40 ` Sasha Levin
2011-05-30 8:49 ` Ingo Molnar
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