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[Qemu-devel] [PATCH v2 0/3] implement a new icount sleep=no mode

From: Victor CLEMENT
Subject: [Qemu-devel] [PATCH v2 0/3] implement a new icount sleep=no mode
Date: Fri, 29 May 2015 17:14:03 +0200

This patch adds a new icount_sleep mode set by the new 'sleep' parameter
of the icount option.
When using sleep=no mode, the QEMU_VIRTUAL_CLOCK will be running at
the maximal possible speed by warping the CPU sleep times to the soonest
virtual clock deadline.
The goal is to get deterministic execution times by preventing potential
latencies from qemu execution on the host machine.
The virtual cpus sleep time will be calculated but not spent, hence the
virtual time will not be realistic when looking from the host point of view
(ex. a 'sleep 10' on the guest will return almost instantly while the
guest clock wil act like 10s have really passed)

This new mode will be used for testing real-time applications inside qemu.
It makes the virtual clock "purely" virtual by removing any reference to
host clocks in the calculation of QEMU_VIRTUAL_CLOCK value.

To test real-time software using this mode, one need to write some scenario
which will simulate inputs on an emulated device then record traces from
this inputs and the associated outputs from the tested software.

Victor CLEMENT (3):
  icount: implement a new icount_sleep mode toggleing real-time cpu
  icount: add sleep parameter to the icount option to set icount_sleep
  icount: print a warning if there is no more deadline in sleep=no mode

 cpus.c          | 85 +++++++++++++++++++++++++++++++++++++++------------------
 qemu-options.hx | 12 ++++++--
 vl.c            |  3 ++
 3 files changed, 72 insertions(+), 28 deletions(-)


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