Adding qemu as a submodule of KVMFORNFV

This Patch includes the changes to add qemu as a submodule to
kvmfornfv repo and make use of the updated latest qemu for the
execution of all testcase
Change-Id: I1280af507a857675c7f81d30c95255635667bdd7
Signed-off-by:RajithaY<rajithax.yerrumsetty@intel.com>

1 files changed, 0 insertions, 164 deletions

diff --git a/qemu/docs/qcow2-cache.txt b/qemu/docs/qcow2-cache.txt
deleted file mode 100644
index 5bb06072d..000000000
--- a/qemu/docs/qcow2-cache.txt
+++ /dev/null
@@ -1,164 +0,0 @@
-qcow2 L2/refcount cache configuration
-=====================================
-Copyright (C) 2015 Igalia, S.L.
-Author: Alberto Garcia <berto@igalia.com>
-
-This work is licensed under the terms of the GNU GPL, version 2 or
-later. See the COPYING file in the top-level directory.
-
-Introduction
-------------
-The QEMU qcow2 driver has two caches that can improve the I/O
-performance significantly. However, setting the right cache sizes is
-not a straightforward operation.
-
-This document attempts to give an overview of the L2 and refcount
-caches, and how to configure them.
-
-Please refer to the docs/specs/qcow2.txt file for an in-depth
-technical description of the qcow2 file format.
-
-
-Clusters
---------
-A qcow2 file is organized in units of constant size called clusters.
-
-The cluster size is configurable, but it must be a power of two and
-its value 512 bytes or higher. QEMU currently defaults to 64 KB
-clusters, and it does not support sizes larger than 2MB.
-
-The 'qemu-img create' command supports specifying the size using the
-cluster_size option:
-
-   qemu-img create -f qcow2 -o cluster_size=128K hd.qcow2 4G
-
-
-The L2 tables
--------------
-The qcow2 format uses a two-level structure to map the virtual disk as
-seen by the guest to the disk image in the host. These structures are
-called the L1 and L2 tables.
-
-There is one single L1 table per disk image. The table is small and is
-always kept in memory.
-
-There can be many L2 tables, depending on how much space has been
-allocated in the image. Each table is one cluster in size. In order to
-read or write data from the virtual disk, QEMU needs to read its
-corresponding L2 table to find out where that data is located. Since
-reading the table for each I/O operation can be expensive, QEMU keeps
-an L2 cache in memory to speed up disk access.
-
-The size of the L2 cache can be configured, and setting the right
-value can improve the I/O performance significantly.
-
-
-The refcount blocks
--------------------
-The qcow2 format also mantains a reference count for each cluster.
-Reference counts are used for cluster allocation and internal
-snapshots. The data is stored in a two-level structure similar to the
-L1/L2 tables described above.
-
-The second level structures are called refcount blocks, are also one
-cluster in size and the number is also variable and dependent on the
-amount of allocated space.
-
-Each block contains a number of refcount entries. Their size (in bits)
-is a power of two and must not be higher than 64. It defaults to 16
-bits, but a different value can be set using the refcount_bits option:
-
-   qemu-img create -f qcow2 -o refcount_bits=8 hd.qcow2 4G
-
-QEMU keeps a refcount cache to speed up I/O much like the
-aforementioned L2 cache, and its size can also be configured.
-
-
-Choosing the right cache sizes
-------------------------------
-In order to choose the cache sizes we need to know how they relate to
-the amount of allocated space.
-
-The amount of virtual disk that can be mapped by the L2 and refcount
-caches (in bytes) is:
-
-   disk_size = l2_cache_size * cluster_size / 8
-   disk_size = refcount_cache_size * cluster_size * 8 / refcount_bits
-
-With the default values for cluster_size (64KB) and refcount_bits
-(16), that is
-
-   disk_size = l2_cache_size * 8192
-   disk_size = refcount_cache_size * 32768
-
-So in order to cover n GB of disk space with the default values we
-need:
-
-   l2_cache_size = disk_size_GB * 131072
-   refcount_cache_size = disk_size_GB * 32768
-
-QEMU has a default L2 cache of 1MB (1048576 bytes) and a refcount
-cache of 256KB (262144 bytes), so using the formulas we've just seen
-we have
-
-   1048576 / 131072 = 8 GB of virtual disk covered by that cache
-    262144 /  32768 = 8 GB
-
-
-How to configure the cache sizes
---------------------------------
-Cache sizes can be configured using the -drive option in the
-command-line, or the 'blockdev-add' QMP command.
-
-There are three options available, and all of them take bytes:
-
-"l2-cache-size":         maximum size of the L2 table cache
-"refcount-cache-size":   maximum size of the refcount block cache
-"cache-size":            maximum size of both caches combined
-
-There are two things that need to be taken into account:
-
- - Both caches must have a size that is a multiple of the cluster
-   size.
-
- - If you only set one of the options above, QEMU will automatically
-   adjust the others so that the L2 cache is 4 times bigger than the
-   refcount cache.
-
-This means that these options are equivalent:
-
-   -drive file=hd.qcow2,l2-cache-size=2097152
-   -drive file=hd.qcow2,refcount-cache-size=524288
-   -drive file=hd.qcow2,cache-size=2621440
-
-The reason for this 1/4 ratio is to ensure that both caches cover the
-same amount of disk space. Note however that this is only valid with
-the default value of refcount_bits (16). If you are using a different
-value you might want to calculate both cache sizes yourself since QEMU
-will always use the same 1/4 ratio.
-
-It's also worth mentioning that there's no strict need for both caches
-to cover the same amount of disk space. The refcount cache is used
-much less often than the L2 cache, so it's perfectly reasonable to
-keep it small.
-
-
-Reducing the memory usage
--------------------------
-It is possible to clean unused cache entries in order to reduce the
-memory usage during periods of low I/O activity.
-
-The parameter "cache-clean-interval" defines an interval (in seconds).
-All cache entries that haven't been accessed during that interval are
-removed from memory.
-
-This example removes all unused cache entries every 15 minutes:
-
-   -drive file=hd.qcow2,cache-clean-interval=900
-
-If unset, the default value for this parameter is 0 and it disables
-this feature.
-
-Note that this functionality currently relies on the MADV_DONTNEED
-argument for madvise() to actually free the memory, so it is not
-useful in systems that don't follow that behavior.