[lkml]   [2017]   [Feb]   [10]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRE: [PATCH 2/2] x86/vdso: Add VCLOCK_HVCLOCK vDSO clock read method
Since sequence count algorithm is done by hypervisor, better to not reuse seqcount.
Still concerned that the code is racy.

-----Original Message-----
From: Thomas Gleixner []
Sent: Friday, February 10, 2017 4:28 AM
To: Vitaly Kuznetsov <>
Cc: Stephen Hemminger <>;; Andy Lutomirski <>; Ingo Molnar <>; H. Peter Anvin <>; KY Srinivasan <>; Haiyang Zhang <>; Dexuan Cui <>;;;
Subject: Re: [PATCH 2/2] x86/vdso: Add VCLOCK_HVCLOCK vDSO clock read method

On Fri, 10 Feb 2017, Vitaly Kuznetsov wrote:

> Stephen Hemminger <> writes:
> > Why not use existing seqlock's?
> >
> To be honest I don't quite understand how we could use it -- the
> sequence locking here is done against the page updated by the
> hypersior, we're not creating new structures (so I don't understand
> how we could use struct seqcount which we don't have) but I may be
> misunderstanding something.

You can't use seqlock, but you might be able to use seqcount. Though I doubt it given the 0 check ....



 \ /
  Last update: 2017-02-10 17:31    [W:0.132 / U:0.384 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site