> Are you trying to use the mutex during a interrupt handler as you can't you
> need something atomic or not able to sleep like a spinlock.
> Nick

I use mutex during FIFO burst write or burst read. I don't want other processes 
to mess up the FIFO access.
spinlock is not for long interval I understand.
Chan

________________________________
보낸 사람 : "nick" <[email protected]>
보낸 날짜 : 2015-06-05 21:34:25 ( +09:00 )
받는 사람 : 김찬 <[email protected]>, [email protected] 
<[email protected]>
참조 :
제목 : Re: I want to sleep while holding a mutex



On 2015-06-05 08:30 AM, Chan Kim wrote:
> Hello,
> I need to write to and read from a Ethernet chip's FIFO and for that I want 
> to use DMA controller. So I modified an existing driver and made the process 
> to sleep using wait_event_interruptible after triggering DMA transfer and 
> made it woken up by ISR using wake_up_interruptible. My problem is that the 
> original driver was using spinlock to protect the FIFO access. But as all 
> know, while holding spinlock, I should not sleep. So I tried replacing 
> spinlock with mutex. (Because, I might sleep while acquiring the mutex, and 
> after getting the mutex, I'll sleep again after DMA trigger. I get woken up 
> by the ISR, and I'll release the mutex. No problem! I thought. ) But I still 
> get this 'scheduling while atomic BUG'. The question is : I need to go to 
> sleep until DMA completion while holding a lock (for FIFO read and write). 
> Isn't it ok to sleep while holding a mutex?
> Best regards,
> Chan Kim
> _______________________________________________
> Kernelnewbies mailing list
> [email protected]
> http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
>
Are you trying to use the mutex during a interrupt handler as you can't you 
need something
atomic or not able to sleep like a spinlock.
Nick
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