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 [mailto:t...@linutronix.de] Sent: Friday, February 10, 2017 4:28 AM To: Vitaly Kuznetsov <vkuzn...@redhat.com> Cc: Stephen Hemminger <sthem...@microsoft.com>; x...@kernel.org; Andy Lutomirski <l...@amacapital.net>; Ingo Molnar <mi...@redhat.com>; H. Peter Anvin <h...@zytor.com>; KY Srinivasan <k...@microsoft.com>; Haiyang Zhang <haiya...@microsoft.com>; Dexuan Cui <de...@microsoft.com>; linux-ker...@vger.kernel.org; de...@linuxdriverproject.org; virtualizat...@lists.linux-foundation.org Subject: Re: [PATCH 2/2] x86/vdso: Add VCLOCK_HVCLOCK vDSO clock read method On Fri, 10 Feb 2017, Vitaly Kuznetsov wrote: > Stephen Hemminger <sthem...@microsoft.com> 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 .... Thanks, tglx _______________________________________________ devel mailing list de...@linuxdriverproject.org http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
