Re: [PATCH v2] block: fix peeking requests during PM

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

 



On Fri, Oct 20, 2017 at 04:45:23PM +0200, Christoph Hellwig wrote:
> We need to look for an active PM request until the next softbarrier
> instead of looking for the first non-PM request.  Otherwise any cause
> of request reordering might starve the PM request(s).

Hi Christoph,

Could you share us how the starve is caused? Looks all PM
request is run via scsi_execute(), and the caller is always
waiting for the completion of PM request.

Especially PM request is run after SCSI device is in quiesce
state, during that time, no normal(non-preempt) request can
enter queue after the making quiesce safe patchset is merged.

--
Ming



[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