Re: [PATCHv3 0/4] Use ticket locks for spinlocks

[Jennifer Herbert <Jennifer.Herbert@citrix.com>]

On 21/04/15 11:22, Jan Beulich wrote:
> Despite both pictures saying micro-seconds at the respective axis (and 
> hence the problem not being _as bad_) - did the data collection reveal 
> where these IRQ disable regions are, so we could look into eliminating 
> them? (ISTR there being some open coded IRQ-disable, lock, unlock, 
> IRQ-restore/enable sequences, but I'm not sure whether they got 
> eliminated already.) Jan 

The location of the locks was not collected, (Other then if it was from 
a spinlock or not) but I'm certainly considering doing this, as another 
graph of duration against cumulative time, shows the majority of time 
spent with interrupts disabled, is during code that keeps it disabled 
for long contiguous periods, all using raw (not spinlock) Interrupt 
disable.  (A few occurrences, but very long when they happen)  It would 
certainly be interesting to know where these come from.

-jenny