Re: [PATCH 1/1] nbd: fix max number of supported devs

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

 



On 8/4/19 1:10 PM, Mike Christie wrote:
> This fixes a bug added in 4.10 with commit:
> 
> commit 9561a7ade0c205bc2ee035a2ac880478dcc1a024
> Author: Josef Bacik <jbacik@xxxxxx>
> Date:   Tue Nov 22 14:04:40 2016 -0500
> 
>      nbd: add multi-connection support
> 
> that limited the number of devices to 256. Before the patch we could
> create 1000s of devices, but the patch switched us from using our
> own thread to using a work queue which has a default limit of 256
> active works.
> 
> The problem is that our recv_work function sits in a loop until
> disconnection but only handles IO for one connection. The work is
> started when the connection is started/restarted, but if we end up
> creating 257 or more connections, the queue_work call just queues
> connection257+'s recv_work and that waits for connection 1 - 256's
> recv_work to be disconnected and that work instance completing.
> 
> Instead of reverting back to kthreads, this has us allocate a
> workqueue_struct per device, so we can block in the work.

Applied for 5.4, thanks Mike.

-- 
Jens Axboe




[Index of Archives]     [Linux RAID]     [Linux SCSI]     [Linux ATA RAID]     [IDE]     [Linux Wireless]     [Linux Kernel]     [ATH6KL]     [Linux Bluetooth]     [Linux Netdev]     [Kernel Newbies]     [Security]     [Git]     [Netfilter]     [Bugtraq]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Device Mapper]

  Powered by Linux