Skip to content

KVM: In-kernel PIT model

Yang, Sheng kvm 1 version In review

Get series with b4
b4 am [email protected]

Versions newest first

  1. v1 Latest2 patches 3 repliesIn review

Patches in v1 No applies recorded yet

#Subject and filesSizeRepliesApplied
1/2KVM: In-kernel PIT modelarch/x86/kvm/Makefile arch/x86/kvm/i8254.c arch/x86/kvm/i8254.h +4 more+754 -11 reply
2/2kvm: libkvm/qemu: Support in-kernel PIT modelkernel/Kbuild libkvm/kvm-common.h libkvm/libkvm.c +4 more+68 -21 reply

Reviews trailers per patch

No Reviewed-by, Acked-by or Tested-by trailers for v1 yet.

Read the v1 thread

Cover letter [PATCH 0/2]KVM: In-kernel PIT model

Hi,

Here is the updated in-kernel PIT model. The main improvements are:

1. The support of SMP PAE host is OK now.

2. The strategy of inject timer interrupt changed. To prevent much more interrupt injection in some SMP guest(for example, more than 50k trying for 1k interrupts per second), the strategy was changed to try to ensure last interrupt was injected, then inject the next one. Also add time out to in case of interrupts lost.

3. Find a bug of QEMU PIT causing a little more PIT interrupts were injected(36.4 interrupts were injected per second, causing 2.6.16 guest timer run faster more than 1/10). Disable QEMU PIT now.

The test result is pretty well with both UP and SMP guest, mostly with default kernel paramters. But RHEL5/5.1 SMP
PAE guest need "clocksource=pit" to make it stable, otherwise may meet the same problem in currently RHEL5.1 SMP PAE guest. If hang occurs, seems only the time out part of PIT interrupts would be injected. For seems it's due to other clocksource, I would check that later.

Signature · 7 lines
Thanks
Yang, Sheng

-------------------------------------------------------------------------
This SF.net email is sponsored by: Microsoft
Defy all challenges. Microsoft(R) Visual Studio 2008.
http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/

Read the cover letter in its thread