[dm-devel] [PATCH 1/3] dm: a basic support for using the select or poll function

[Martin Wilck]

On Thu, 2017-05-11 at 11:39 +0200, Martin Wilck wrote:
> On Tue, 2017-05-09 at 12:10 -0700, Andy Grover wrote:
> > From: Mikulas Patocka <mpatocka at redhat.com>
> >  
> > This is the very simple patch for polling on the
> > /dev/mapper/control
> > device. The select or poll function waits until any event happens
> > on
> > any
> > dm device since opening the /dev/mapper/control device. When select
> > or
> > poll returns the device as readable, we must close and reopen the
> > device
> > to wait for new dm events.
> 
> Why have you done it that way? Couldn't you just save the
> dm_global_event_nr at the time poll() is called?

I should have read your patch 2/3 before posting ... but I'm still
missing why the counter can't simply be set at poll() time.

Regards
Martin
-- 
Dr. Martin Wilck <mwilck at suse.com>, Tel. +49 (0)911 74053 2107
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