Re: [PATCH] drivers/char/pcmcia/synclink_cs.c: BKL pushdown?

From: Paul Fulghum
Date: Fri Oct 02 2009 - 09:41:21 EST


Alan Cox wrote:
> On Fri, 02 Oct 2009 19:37:21 +0900
> lenrek@xxxxxx wrote:
>
>> I found the counterpart of function mgslpc_wait_until_sent
>> in drivers/char/synclinkmp.c (wait_until_sent) is modified to
>> issue (un)lock_kernel. This patch does the same modification.
>>
>> However, I'm afraid similar modifications are necessary further on
>> functions
>> mgslpc_ioctl and mgslpc_write_room.
>
> The push down work normally eliminated BKL calls that were demonstrably
> not needed and left it in anywhere that needed thought. Do those
> functions still really need the BKL ?

No, these functions use a device specific spinlock (info->lock)
when needed. Not even mgslpc_wait_until_sent needs BKL.

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Paul Fulghum
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