From: Paul Mackerras <paulus@samba.org>
To: Alexander Graf <agraf@suse.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>,
"kvm-ppc@vger.kernel.org" <kvm-ppc@vger.kernel.org>,
"kvm@vger.kernel.org" <kvm@vger.kernel.org>
Subject: Re: [PATCH 19/23] KVM: PPC: Book3S: Select PR vs HV separately for each guest
Date: Wed, 18 Sep 2013 12:05:13 +0000 [thread overview]
Message-ID: <20130918120513.GA9372@iris.ozlabs.ibm.com> (raw)
In-Reply-To: <DE9B8555-4DE9-4A15-97E3-1EAF203AC153@suse.de>
On Thu, Sep 12, 2013 at 11:17:11PM -0500, Alexander Graf wrote:
>
> It means you can only choose between HV and PR machine wide, while with this patch set you give the user the flexibility to have HV and PR guests run in parallel.
>
> I know that Anthony doesn't believe it's a valid use case, but I like the flexible solution better. It does however male sense to enable a sysadmin to remove any PR functionality from the system by blocking that module.
>
> Can't we have both?
So, one suggestion (from Aneesh) is to use the 'type' argument to
kvm_arch_init_vm() to indicate whether we want a specific type of KVM
(PR or HV), or just the default. Zero would mean default (fastest
available) whereas other values would indicate a specific choice of PR
or HV. Then, if we build separate kvm_pr and kvm_hv modules when KVM
is configured to be a module, the sysadmin can control the default
choice by loading and unloading modules.
How does that sound? Or would you prefer to stick with a single
module and have a module option to control the default choice?
Paul.
WARNING: multiple messages have this Message-ID (diff)
From: Paul Mackerras <paulus@samba.org>
To: Alexander Graf <agraf@suse.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>,
"kvm-ppc@vger.kernel.org" <kvm-ppc@vger.kernel.org>,
"kvm@vger.kernel.org" <kvm@vger.kernel.org>
Subject: Re: [PATCH 19/23] KVM: PPC: Book3S: Select PR vs HV separately for each guest
Date: Wed, 18 Sep 2013 22:05:13 +1000 [thread overview]
Message-ID: <20130918120513.GA9372@iris.ozlabs.ibm.com> (raw)
In-Reply-To: <DE9B8555-4DE9-4A15-97E3-1EAF203AC153@suse.de>
On Thu, Sep 12, 2013 at 11:17:11PM -0500, Alexander Graf wrote:
>
> It means you can only choose between HV and PR machine wide, while with this patch set you give the user the flexibility to have HV and PR guests run in parallel.
>
> I know that Anthony doesn't believe it's a valid use case, but I like the flexible solution better. It does however male sense to enable a sysadmin to remove any PR functionality from the system by blocking that module.
>
> Can't we have both?
So, one suggestion (from Aneesh) is to use the 'type' argument to
kvm_arch_init_vm() to indicate whether we want a specific type of KVM
(PR or HV), or just the default. Zero would mean default (fastest
available) whereas other values would indicate a specific choice of PR
or HV. Then, if we build separate kvm_pr and kvm_hv modules when KVM
is configured to be a module, the sysadmin can control the default
choice by loading and unloading modules.
How does that sound? Or would you prefer to stick with a single
module and have a module option to control the default choice?
Paul.
next prev parent reply other threads:[~2013-09-18 12:05 UTC|newest]
Thread overview: 136+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-08-06 4:12 [PATCH 00/23] Allow PR and HV KVM to coexist in one kernel Paul Mackerras
2013-08-06 4:12 ` Paul Mackerras
2013-08-06 4:13 ` [PATCH 01/23] KVM: PPC: Book3S: Fix compile error in XICS emulation Paul Mackerras
2013-08-06 4:13 ` Paul Mackerras
2013-08-28 22:51 ` Alexander Graf
2013-08-28 22:51 ` Alexander Graf
2013-08-06 4:14 ` [PATCH 02/23] KVM: PPC: Book3S PR: Don't corrupt guest state when kernel uses VMX Paul Mackerras
2013-08-06 4:14 ` Paul Mackerras
2013-08-08 15:49 ` Aneesh Kumar K.V
2013-08-08 15:49 ` Aneesh Kumar K.V
2013-08-28 22:51 ` Alexander Graf
2013-08-28 22:51 ` Alexander Graf
2013-08-06 4:15 ` [PATCH 03/23] KVM: PPC: Book3S PR: Make instruction fetch fallback work for system calls Paul Mackerras
2013-08-06 4:15 ` Paul Mackerras
2013-08-28 22:51 ` Alexander Graf
2013-08-28 22:51 ` Alexander Graf
2013-08-06 4:16 ` [PATCH 04/23] KVM: PPC: Book3S PR: Keep volatile reg values in vcpu rather than shadow_vcpu Paul Mackerras
2013-08-06 4:16 ` Paul Mackerras
2013-08-11 11:06 ` Aneesh Kumar K.V
2013-08-11 11:18 ` Aneesh Kumar K.V
2013-08-28 22:00 ` Alexander Graf
2013-08-28 22:00 ` Alexander Graf
2013-08-29 5:04 ` Paul Mackerras
2013-08-29 5:04 ` Paul Mackerras
2013-08-29 12:46 ` Alexander Graf
2013-08-29 12:46 ` Alexander Graf
2013-08-06 4:18 ` [PATCH 05/23] KVM: PPC: Book3S PR: Rework kvmppc_mmu_book3s_64_xlate() Paul Mackerras
2013-08-06 4:18 ` Paul Mackerras
2013-08-28 22:51 ` Alexander Graf
2013-08-28 22:51 ` Alexander Graf
2013-08-06 4:18 ` [PATCH 06/23] KVM: PPC: Book3S PR: Allow guest to use 64k pages Paul Mackerras
2013-08-06 4:18 ` Paul Mackerras
2013-08-28 22:56 ` Alexander Graf
2013-08-28 22:56 ` Alexander Graf
2013-08-29 5:17 ` Paul Mackerras
2013-08-29 5:17 ` Paul Mackerras
2013-08-29 12:48 ` Alexander Graf
2013-08-29 12:48 ` Alexander Graf
2013-08-06 4:19 ` [PATCH 07/23] KVM: PPC: Book3S PR: Use 64k host pages where possible Paul Mackerras
2013-08-06 4:19 ` Paul Mackerras
2013-08-28 23:24 ` Alexander Graf
2013-08-28 23:24 ` Alexander Graf
2013-08-29 5:23 ` Paul Mackerras
2013-08-29 5:23 ` Paul Mackerras
2013-08-29 12:43 ` Alexander Graf
2013-08-29 12:43 ` Alexander Graf
2013-08-06 4:20 ` [PATCH 08/23] KVM: PPC: Book3S PR: Handle PP0 page-protection bit in guest HPTEs Paul Mackerras
2013-08-06 4:20 ` Paul Mackerras
2013-08-06 4:20 ` [PATCH 09/23] KVM: PPC: Book3S PR: Correct errors in H_ENTER implementation Paul Mackerras
2013-08-06 4:20 ` Paul Mackerras
2013-08-06 4:21 ` [PATCH 10/23] KVM: PPC: Book3S PR: Make HPT accesses and updates SMP-safe Paul Mackerras
2013-08-06 4:21 ` Paul Mackerras
2013-08-06 4:21 ` [PATCH 11/23] KVM: PPC: Book3S PR: Allocate kvm_vcpu structs from kvm_vcpu_cache Paul Mackerras
2013-08-06 4:21 ` Paul Mackerras
2013-08-12 10:03 ` Aneesh Kumar K.V
2013-08-12 10:15 ` Aneesh Kumar K.V
2013-08-06 4:22 ` [PATCH 12/23] KVM: PPC: Book3S HV: Better handling of exceptions that happen in real mode Paul Mackerras
2013-08-06 4:22 ` Paul Mackerras
2013-08-06 4:22 ` [PATCH 13/23] KVM: PPC: Book3S: Move skip-interrupt handlers to common code Paul Mackerras
2013-08-06 4:22 ` Paul Mackerras
2013-08-06 4:23 ` [PATCH 14/23] KVM: PPC: Book3S PR: Delay disabling relocation-on interrupts Paul Mackerras
2013-08-06 4:23 ` Paul Mackerras
2013-08-30 16:30 ` Alexander Graf
2013-08-30 16:30 ` Alexander Graf
2013-08-30 22:55 ` Paul Mackerras
2013-08-30 22:55 ` Paul Mackerras
2013-08-30 23:13 ` Alexander Graf
2013-08-30 23:13 ` Alexander Graf
2013-08-31 5:42 ` Paul Mackerras
2013-08-31 5:42 ` Paul Mackerras
2013-08-06 4:24 ` [PATCH 15/23] KVM: PPC: Book3S: Rename symbols that exist in both PR and HV KVM Paul Mackerras
2013-08-06 4:24 ` Paul Mackerras
2013-08-06 4:24 ` [PATCH 16/23] KVM: PPC: Book3S: Merge implementations of KVM_PPC_GET_SMMU_INFO ioctl Paul Mackerras
2013-08-06 4:24 ` Paul Mackerras
2013-08-06 4:25 ` [PATCH 17/23] KVM: PPC: Book3S HV: Factorize kvmppc_core_vcpu_create_hv() Paul Mackerras
2013-08-06 4:25 ` Paul Mackerras
2013-08-06 4:25 ` [PATCH 18/23] KVM: PPC: Book3S: Allow both PR and HV KVM to be selected Paul Mackerras
2013-08-06 4:25 ` Paul Mackerras
2013-08-06 4:26 ` [PATCH 19/23] KVM: PPC: Book3S: Select PR vs HV separately for each guest Paul Mackerras
2013-08-06 4:26 ` Paul Mackerras
2013-09-12 22:56 ` Alexander Graf
2013-09-12 22:56 ` Alexander Graf
2013-09-13 0:17 ` Paul Mackerras
2013-09-13 0:17 ` Paul Mackerras
2013-09-13 1:31 ` Benjamin Herrenschmidt
2013-09-13 1:31 ` Benjamin Herrenschmidt
2013-09-13 4:18 ` Alexander Graf
2013-09-13 4:18 ` Alexander Graf
2013-09-14 18:33 ` Aneesh Kumar K.V
2013-09-14 18:45 ` Aneesh Kumar K.V
2013-09-14 20:22 ` Alexander Graf
2013-09-14 20:22 ` Alexander Graf
2013-09-15 9:16 ` Aneesh Kumar K.V
2013-09-15 9:28 ` Aneesh Kumar K.V
2013-09-15 11:55 ` Alexander Graf
2013-09-15 11:55 ` Alexander Graf
2013-09-13 4:17 ` Alexander Graf
2013-09-13 4:17 ` Alexander Graf
2013-09-18 12:05 ` Paul Mackerras [this message]
2013-09-18 12:05 ` Paul Mackerras
2013-09-19 7:31 ` Alexander Graf
2013-09-19 7:31 ` Alexander Graf
2013-08-06 4:27 ` [PATCH 20/23] KVM: PPC: Book3S PR: Better handling of host-side read-only pages Paul Mackerras
2013-08-06 4:27 ` Paul Mackerras
2013-09-12 23:01 ` Alexander Graf
2013-09-12 23:01 ` Alexander Graf
2013-09-13 0:23 ` Paul Mackerras
2013-09-13 0:23 ` Paul Mackerras
2013-09-14 5:24 ` Paul Mackerras
2013-09-14 5:24 ` Paul Mackerras
2013-09-14 20:23 ` Alexander Graf
2013-09-14 20:23 ` Alexander Graf
2013-09-16 4:12 ` Paul Mackerras
2013-09-16 4:12 ` Paul Mackerras
2013-09-16 12:47 ` Alexander Graf
2013-09-16 12:47 ` Alexander Graf
2013-08-06 4:27 ` [PATCH 21/23] KVM: PPC: Book3S PR: Use mmu_notifier_retry() in kvmppc_mmu_map_page() Paul Mackerras
2013-08-06 4:27 ` Paul Mackerras
2013-08-07 4:13 ` Bhushan Bharat-R65777
2013-08-07 4:13 ` Bhushan Bharat-R65777
2013-08-07 4:28 ` Paul Mackerras
2013-08-07 4:28 ` Paul Mackerras
2013-08-07 5:18 ` Bhushan Bharat-R65777
2013-08-07 5:18 ` Bhushan Bharat-R65777
2013-08-07 5:17 ` Bhushan Bharat-R65777
2013-08-07 5:17 ` Bhushan Bharat-R65777
2013-08-07 8:27 ` Paul Mackerras
2013-08-07 8:27 ` Paul Mackerras
2013-08-07 8:31 ` Bhushan Bharat-R65777
2013-08-07 8:31 ` Bhushan Bharat-R65777
2013-08-08 12:06 ` Paul Mackerras
2013-08-08 12:06 ` Paul Mackerras
2013-08-06 4:27 ` [PATCH 22/23] KVM: PPC: Book3S PR: Mark pages accessed, and dirty if being written Paul Mackerras
2013-08-06 4:27 ` Paul Mackerras
2013-08-06 4:28 ` [PATCH 23/23] KVM: PPC: Book3S PR: Reduce number of shadow PTEs invalidated by MMU notifiers Paul Mackerras
2013-08-06 4:28 ` Paul Mackerras
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