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Date:   Fri, 23 Oct 2020 13:44:01 +1100 (AEDT)
From:   Finn Thain <fthain@telegraphics.com.au>
To:     Tianxianting <tian.xianting@h3c.com>
cc:     "kashyap.desai@broadcom.com" <kashyap.desai@broadcom.com>,
        "sumit.saxena@broadcom.com" <sumit.saxena@broadcom.com>,
        "shivasharan.srikanteshwara@broadcom.com" 
        <shivasharan.srikanteshwara@broadcom.com>,
        "jejb@linux.ibm.com" <jejb@linux.ibm.com>,
        "martin.petersen@oracle.com" <martin.petersen@oracle.com>,
        "megaraidlinux.pdl@broadcom.com" <megaraidlinux.pdl@broadcom.com>,
        "linux-scsi@vger.kernel.org" <linux-scsi@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: RE: [PATCH] scsi: megaraid_sas: use spin_lock() in hard IRQ
In-Reply-To: <89c5cb05cb844939ae684db0077f675f@h3c.com>
Message-ID: <alpine.LNX.2.23.453.2010231324510.6@nippy.intranet>
References: <20201021064502.35469-1-tian.xianting@h3c.com> <alpine.LNX.2.23.453.2010221312460.6@nippy.intranet> <9923f28dd2b34499a17c53e8fa33f1ca@h3c.com> <alpine.LNX.2.23.453.2010221424390.6@nippy.intranet> <89c5cb05cb844939ae684db0077f675f@h3c.com>
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On Thu, 22 Oct 2020, Tianxianting wrote:

> I see, If we add this patch, we need to get all cpu arch that support 
> nested interrupts.
> 

I was just calling into question 1. the benefit (does it improve 
performance?) and 2. the code style (is it less portable?).

It's really the style question that mostly interests me because I've had 
to code around the nested interrupt situation before, and everytime it 
comes up it makes me wonder about the necessity.

I was not trying to veto your patch. It is not my position to do that. If 
Broadcom likes the patch, that's great.