On Mon, Mar 12, 2018 at 9:24 PM, Andrea Parri wrote:
> Hi Trol,
>
> [...]
>
>
>> But this is just one special case that acquire-release chains promise us.
>>
>> A=B=0 as initial
>>
>> CPU0CPU1CPU2CPU3
>> write A=1
>>rea
On Mon, Mar 12, 2018 at 05:13:03PM +0800, 焦晓冬 wrote:
> If the fixed comment could point out where this RCsc is used, it will be
> great.
The one that comes to mind first is RCU-sched, that relies on a context
switch implying a full smp_mb(). But I think there's more..
Hi Trol,
[...]
> But this is just one special case that acquire-release chains promise us.
>
> A=B=0 as initial
>
> CPU0CPU1CPU2CPU3
> write A=1
>read A=1
>write B=1
>
On Mon, Mar 12, 2018 at 4:56 PM, Peter Zijlstra wrote:
> On Mon, Mar 12, 2018 at 04:56:00PM +0800, Boqun Feng wrote:
>> So I think the purpose of smp_mb__after_spinlock() is to provide RCsc
>> locks, it's just the comments before that may be misleading. We want
>> RCsc locks in schedule code becau
On Mon, Mar 12, 2018 at 04:56:00PM +0800, Boqun Feng wrote:
> So I think the purpose of smp_mb__after_spinlock() is to provide RCsc
> locks, it's just the comments before that may be misleading. We want
> RCsc locks in schedule code because we want writes in different critical
> section are ordered
On Mon, Mar 12, 2018 at 04:18:00PM +0800, 焦晓冬 wrote:
> >> Peter pointed out in this patch https://patchwork.kernel.org/patch/9771921/
> >> that the spinning-lock used at __schedule() should be RCsc to ensure
> >> visibility of writes prior to __schedule when the task is to be migrated to
> >> anoth
>> Peter pointed out in this patch https://patchwork.kernel.org/patch/9771921/
>> that the spinning-lock used at __schedule() should be RCsc to ensure
>> visibility of writes prior to __schedule when the task is to be migrated to
>> another CPU.
>>
>> And this is emphasized at the comment of the ne
On Sun, Mar 11, 2018 at 03:55:41PM +0800, 焦晓冬 wrote:
> Peter pointed out in this patch https://patchwork.kernel.org/patch/9771921/
> that the spinning-lock used at __schedule() should be RCsc to ensure
> visibility of writes prior to __schedule when the task is to be migrated to
> another CPU.
>
>
Peter pointed out in this patch https://patchwork.kernel.org/patch/9771921/
that the spinning-lock used at __schedule() should be RCsc to ensure
visibility of writes prior to __schedule when the task is to be migrated to
another CPU.
And this is emphasized at the comment of the newly introduced
sm
9 matches
Mail list logo
