Subject: Re: [linuxppc-release] [PATCH v3 4/4] fsl-dma: use spin_lock_bh to instead of spin_lock_irqsave

From: Timur Tabi <[email-masked]>
Date: Tue, 17 Jul 2012 10:29:11 -0500

Liu Qiang-B32616 wrote:
> I attached the test result in v3 0/4, performance is improved by 2%.
> For my understanding, there is not any place to access descriptor lists
> in fsl-dma interrupt service handler except its tasklet, spin_lock_bh()
> is born for this. Interrupts will be turned off and context will be save in
> irqsave, there is needless to use irqsave in our case. You can refer to the
> implement of mv_xor.c or ioap-adma.c.
> If you think my explanation is ok, I can add it in the patch.

Yes, the explanation is ok.  Please make it part of the patch description,
so that it is saved in the git history.

-- 
Timur Tabi
Linux kernel developer at Freescale