Re: LOCKDEP: 3.9-rc1: mount.nfs/4272 still has locks held!

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Wed, Mar 6, 2013 at 10:53 AM, Tejun Heo <tj@xxxxxxxxxx> wrote:
> Hello, Oleg.
>
> On Wed, Mar 06, 2013 at 07:16:08PM +0100, Oleg Nesterov wrote:
>> And how SIGFREEZE can help? If we want to interrupt the sleeps in NFS/RPC
>> layer we can simply add TASK_WAKEFREEZE (can be used with TASK_KILLABLE)
>> and change freeze_task() to do signal_wake_up_state(TASK_WAKEFREEZE).
>
> Oh yeah, we don't need another signal.  We just need sigpending state
> and a wakeup.  I wasn't really going into details.  The important
> point is that for code paths outside signal/ptrace, freezing could
> look and behave about the same as signal delivery.

Don't we already do that? The whole "try_to_freeze()" in
get_signal_to_deliver() is about exactly this. See
fake_signal_wake_up().

You still have kernel threads (that don't do signals) to worry about,
so it doesn't make things go away. And you still have issues with
latency of disk wait, which is, I think, the reason for that
"freezable_schedule()" in the NFS code to begin with.

               Linus
--
To unsubscribe from this list: send the line "unsubscribe linux-nfs" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html


[Index of Archives]     [Linux Filesystem Development]     [Linux USB Development]     [Linux Media Development]     [Video for Linux]     [Linux NILFS]     [Linux Audio Users]     [Yosemite Info]     [Linux SCSI]

  Powered by Linux