Merge remote-tracking branch 'remotes/juanquintela/tags/migration/20150507-1' into staging

migration/next for 20150507

# gpg: Signature made Thu May  7 17:42:19 2015 BST using RSA key ID 5872D723
# gpg: Good signature from "Juan Quintela <quintela@redhat.com>"
# gpg:                 aka "Juan Quintela <quintela@trasno.org>"

* remotes/juanquintela/tags/migration/20150507-1:
  migration: Fix migration state update issue
  migration: avoid divide by zero in xbzrle cache miss rate
  migration: Add hmp interface to set and query parameters
  migration: Add qmp commands to set and query parameters
  migration: Use an array instead of 3 parameters
  migration: Add interface to control compression
  migration: Add the core code for decompression
  migration: Make compression co-work with xbzrle
  migration: Add the core code of multi-thread compression
  migration: Split save_zero_page from ram_save_page
  arch_init: Add and free data struct for decompression
  arch_init: Alloc and free data struct for compression
  qemu-file: Add compression functions to QEMUFile
  migration: Add the framework of multi-thread decompression
  migration: Add the framework of multi-thread compression
  docs: Add a doc about multiple thread compression

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 78 insertions, 1 deletions

diff --git a/qapi-schema.json b/qapi-schema.json
index 27ec9882db..9c92482898 100644
--- a/qapi-schema.json
+++ b/qapi-schema.json
@@ -515,13 +515,22 @@
 #          to enable the capability on the source VM. The feature is disabled by
 #          default. (since 1.6)
 #
+# @compress: Use multiple compression threads to accelerate live migration.
+#          This feature can help to reduce the migration traffic, by sending
+#          compressed pages. Please note that if compress and xbzrle are both
+#          on, compress only takes effect in the ram bulk stage, after that,
+#          it will be disabled and only xbzrle takes effect, this can help to
+#          minimize migration traffic. The feature is disabled by default.
+#          (since 2.4 )
+#
 # @auto-converge: If enabled, QEMU will automatically throttle down the guest
 #          to speed up convergence of RAM migration. (since 1.6)
 #
 # Since: 1.2
 ##
 { 'enum': 'MigrationCapability',
-  'data': ['xbzrle', 'rdma-pin-all', 'auto-converge', 'zero-blocks'] }
+  'data': ['xbzrle', 'rdma-pin-all', 'auto-converge', 'zero-blocks',
+           'compress'] }
 
 ##
 # @MigrationCapabilityStatus
@@ -560,6 +569,74 @@
 ##
 { 'command': 'query-migrate-capabilities', 'returns':   ['MigrationCapabilityStatus']}
 
+# @MigrationParameter
+#
+# Migration parameters enumeration
+#
+# @compress-level: Set the compression level to be used in live migration,
+#          the compression level is an integer between 0 and 9, where 0 means
+#          no compression, 1 means the best compression speed, and 9 means best
+#          compression ratio which will consume more CPU.
+#
+# @compress-threads: Set compression thread count to be used in live migration,
+#          the compression thread count is an integer between 1 and 255.
+#
+# @decompress-threads: Set decompression thread count to be used in live
+#          migration, the decompression thread count is an integer between 1
+#          and 255. Usually, decompression is at least 4 times as fast as
+#          compression, so set the decompress-threads to the number about 1/4
+#          of compress-threads is adequate.
+#
+# Since: 2.4
+##
+{ 'enum': 'MigrationParameter',
+  'data': ['compress-level', 'compress-threads', 'decompress-threads'] }
+
+#
+# @migrate-set-parameters
+#
+# Set the following migration parameters
+#
+# @compress-level: compression level
+#
+# @compress-threads: compression thread count
+#
+# @decompress-threads: decompression thread count
+#
+# Since: 2.4
+##
+{ 'command': 'migrate-set-parameters',
+  'data': { '*compress-level': 'int',
+            '*compress-threads': 'int',
+            '*decompress-threads': 'int'} }
+
+#
+# @MigrationParameters
+#
+# @compress-level: compression level
+#
+# @compress-threads: compression thread count
+#
+# @decompress-threads: decompression thread count
+#
+# Since: 2.4
+##
+{ 'struct': 'MigrationParameters',
+  'data': { 'compress-level': 'int',
+            'compress-threads': 'int',
+            'decompress-threads': 'int'} }
+##
+# @query-migrate-parameters
+#
+# Returns information about the current migration parameters
+#
+# Returns: @MigrationParameters
+#
+# Since: 2.4
+##
+{ 'command': 'query-migrate-parameters',
+  'returns': 'MigrationParameters' }
+
 ##
 # @MouseInfo:
 #