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Date:   Tue, 12 Jan 2021 09:29:01 -0800
From:   Davidlohr Bueso <dave@stgolabs.net>
To:     Shuo A Liu <shuo.a.liu@intel.com>
Cc:     linux-kernel@vger.kernel.org, x86@kernel.org,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        "H . Peter Anvin" <hpa@zytor.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        Yu Wang <yu1.wang@intel.com>,
        Reinette Chatre <reinette.chatre@intel.com>,
        Zhi Wang <zhi.a.wang@intel.com>,
        Zhenyu Wang <zhenyuw@linux.intel.com>
Subject: Re: [PATCH v7 09/18] virt: acrn: Introduce I/O request management
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On Tue, 12 Jan 2021, Shuo A Liu wrote:

>On Mon 11.Jan'21 at 13:52:19 -0800, Davidlohr Bueso wrote:
>>Could this not be done in process context instead?
>
>It could be. The original consideration with tasklet was more about
>performance as the I/O requests dispatching is a hot code path. I think
>irq thread has little performance impact? I can have a try to convert
>the tasklet to irq thread.

Yes, there is some added latency between when the work is scheduled and
actually executed - however this should not be a problem for this scenario,
and furthermore consider that tasklets do not guarantee performance as
ksoftirqd comes in the picture under heavy load.

Thanks,
Davidlohr