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Date: Wed, 11 Jul 2012 10:01:01 -0500
From: Timur Tabi <timur@freescale.com>
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To: Qiang Liu <qiang.liu@freescale.com>
Subject: Re: [linuxppc-release] [PATCH v2 4/4] fsl-dma: use spin_lock_bh to
 instead of spin_lock_irqsave
References: <1341997326-18495-1-git-send-email-qiang.liu@freescale.com>
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Cc: Vinod Koul <vinod.koul@intel.com>, herbert@gondor.hengli.com.au,
 linux-crypto@vger.kernel.org, Dan Williams <dan.j.williams@intel.com>,
 linuxppc-dev@lists.ozlabs.org, davem@davemloft.net
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Qiang Liu wrote:
> Use spin_lock_bh to instead of spin_lock_irqsave for improving performance.

Please provide some evidence that performance has improved, as well as an
explanation why it's okay to use spin_lock_bh, and why it's faster.

-- 
Timur Tabi
Linux kernel developer at Freescale