Kernel KVM virtualization development
 help / color / mirror / Atom feed
From: Peter Xu <peterx@redhat.com>
To: Andrew Jones <drjones@redhat.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>,
	kvm@vger.kernel.org, pbonzini@redhat.com, frankja@linux.ibm.com,
	bgardon@google.com
Subject: Re: [PATCH 09/11] KVM: selftests: Make vm_create_default common
Date: Thu, 5 Nov 2020 13:45:11 -0500	[thread overview]
Message-ID: <20201105184511.GC106309@xz-x1> (raw)
In-Reply-To: <20201105095930.nofg64qyuf4qertu@kamzik.brq.redhat.com>

On Thu, Nov 05, 2020 at 10:59:30AM +0100, Andrew Jones wrote:
> > >> +#define PTRS_PER_PAGE(page_size)	((page_size) / 8)
> > > 
> > > Doh. I think this 8 is supposed to be a 16 for s390x, considering it
> > > was dividing by 256 in its version of vm_create_default. I need
> > > guidance from s390x gurus as to whether or not I should respin though.
> > > 
> > > Thanks,
> > > drew
> > > 
> > 
> > This is kind of tricky. The last level page table is only 2kb (256 entries = 1MB range).
> > Depending on whether the page table allocation is clever or not (you can have 2 page
> > tables in one page) this means that indeed 16 might be better. But then you actually 
> > want to change the macro name to PTES_PER_PAGE?
> 
> Thanks Christian,
> 
> I'll respin with the macro name change and 16 for s390.

Maybe it can also be moved to common header, but instead define PTR_SIZE for
per-arch?  I'm also curious whether PTR_SIZE will equals to "sizeof(void *)",
but seems not for s390x..  Thanks,

-- 
Peter Xu


  reply	other threads:[~2020-11-05 18:45 UTC|newest]

Thread overview: 24+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-11-04 21:23 [PATCH 00/11] KVM: selftests: Cleanups Andrew Jones
2020-11-04 21:23 ` [PATCH 01/11] KVM: selftests: Add x86_64/tsc_msrs_test to .gitignore Andrew Jones
2020-11-04 21:23 ` [PATCH 02/11] KVM: selftests: Drop pointless vm_create wrapper Andrew Jones
2020-11-04 21:23 ` [PATCH 03/11] KVM: selftests: Always clear dirty bitmap after iteration Andrew Jones
2020-11-04 21:23 ` [PATCH 04/11] KVM: selftests: Use a single binary for dirty/clear log test Andrew Jones
2020-11-04 21:23 ` [PATCH 05/11] KVM: selftests: Introduce after_vcpu_run hook for dirty " Andrew Jones
2020-11-04 21:23 ` [PATCH 06/11] KVM: selftests: Make the per vcpu memory size global Andrew Jones
2020-11-04 21:23 ` [PATCH 07/11] KVM: selftests: Make the number of vcpus global Andrew Jones
2020-11-04 21:23 ` [PATCH 08/11] KVM: selftests: Factor out guest mode code Andrew Jones
2020-11-04 21:23 ` [PATCH 09/11] KVM: selftests: Make vm_create_default common Andrew Jones
2020-11-04 21:36   ` Andrew Jones
2020-11-05  7:18     ` Christian Borntraeger
2020-11-05  9:59       ` Andrew Jones
2020-11-05 18:45         ` Peter Xu [this message]
2020-11-05 18:54           ` Christian Borntraeger
2020-11-04 21:23 ` [PATCH 10/11] KVM: selftests: Introduce vm_create_[default_]vcpus Andrew Jones
2020-11-04 21:23 ` [PATCH 11/11] KVM: selftests: Remove create_vm Andrew Jones
2020-11-05  7:08 ` [PATCH 00/11] KVM: selftests: Cleanups Christian Borntraeger
2020-11-05 18:55 ` Peter Xu
2020-11-05 19:41   ` Ben Gardon
2020-11-06  9:45     ` Andrew Jones
2020-11-06 15:04       ` Peter Xu
2020-11-09 17:11         ` Ben Gardon
2020-11-06 13:01 ` Paolo Bonzini

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20201105184511.GC106309@xz-x1 \
    --to=peterx@redhat.com \
    --cc=bgardon@google.com \
    --cc=borntraeger@de.ibm.com \
    --cc=drjones@redhat.com \
    --cc=frankja@linux.ibm.com \
    --cc=kvm@vger.kernel.org \
    --cc=pbonzini@redhat.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox