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Subject: Re: [Xen-devel] [PATCH] xen/privcmd: sprinkle around cond_resched()
 calls in mmap ioctl handling
To: Jan Beulich <JBeulich@suse.com>, <david.vrabel@citrix.com>,
        <boris.ostrovsky@oracle.com>, Juergen Gross <JGross@suse.com>
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From: David Vrabel <david.vrabel@citrix.com>
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On 07/07/16 08:35, Jan Beulich wrote:
> Many of these operations can take arbitrarily long, which can become a
> problem irrespective of them being exposed to privileged users only.

If this is a concern I would rather see large numbers of mapping
requests processed in smaller batches.  This would also limit the amount
of memory needed.

Note also that xen_remap_domain_gfn() array already has a cond_resched()
after every batch of 16 GFNs.

David