From abb6295b3ace5d17c3a65936913fc346616dbf14 Mon Sep 17 00:00:00 2001 From: Leonardo Bras Date: Fri, 13 May 2022 03:28:33 -0300 Subject: migration: Add zero-copy-send parameter for QMP/HMP for Linux MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Add property that allows zero-copy migration of memory pages on the sending side, and also includes a helper function migrate_use_zero_copy_send() to check if it's enabled. No code is introduced to actually do the migration, but it allow future implementations to enable/disable this feature. On non-Linux builds this parameter is compiled-out. Signed-off-by: Leonardo Bras Reviewed-by: Peter Xu Reviewed-by: Daniel P. Berrangé Reviewed-by: Juan Quintela Acked-by: Markus Armbruster Message-Id: <20220513062836.965425-5-leobras@redhat.com> Signed-off-by: Dr. David Alan Gilbert --- qapi/migration.json | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) (limited to 'qapi/migration.json') diff --git a/qapi/migration.json b/qapi/migration.json index 409eb08..2222f44 100644 --- a/qapi/migration.json +++ b/qapi/migration.json @@ -741,6 +741,13 @@ # will consume more CPU. # Defaults to 1. (Since 5.0) # +# @zero-copy-send: Controls behavior on sending memory pages on migration. +# When true, enables a zero-copy mechanism for sending +# memory pages, if host supports it. +# Requires that QEMU be permitted to use locked memory +# for guest RAM pages. +# Defaults to false. (Since 7.1) +# # @block-bitmap-mapping: Maps block nodes and bitmaps on them to # aliases for the purpose of dirty bitmap migration. Such # aliases may for example be the corresponding names on the @@ -780,6 +787,7 @@ 'xbzrle-cache-size', 'max-postcopy-bandwidth', 'max-cpu-throttle', 'multifd-compression', 'multifd-zlib-level' ,'multifd-zstd-level', + { 'name': 'zero-copy-send', 'if' : 'CONFIG_LINUX'}, 'block-bitmap-mapping' ] } ## @@ -906,6 +914,13 @@ # will consume more CPU. # Defaults to 1. (Since 5.0) # +# @zero-copy-send: Controls behavior on sending memory pages on migration. +# When true, enables a zero-copy mechanism for sending +# memory pages, if host supports it. +# Requires that QEMU be permitted to use locked memory +# for guest RAM pages. +# Defaults to false. (Since 7.1) +# # @block-bitmap-mapping: Maps block nodes and bitmaps on them to # aliases for the purpose of dirty bitmap migration. Such # aliases may for example be the corresponding names on the @@ -960,6 +975,7 @@ '*multifd-compression': 'MultiFDCompression', '*multifd-zlib-level': 'uint8', '*multifd-zstd-level': 'uint8', + '*zero-copy-send': { 'type': 'bool', 'if': 'CONFIG_LINUX' }, '*block-bitmap-mapping': [ 'BitmapMigrationNodeAlias' ] } } ## @@ -1106,6 +1122,13 @@ # will consume more CPU. # Defaults to 1. (Since 5.0) # +# @zero-copy-send: Controls behavior on sending memory pages on migration. +# When true, enables a zero-copy mechanism for sending +# memory pages, if host supports it. +# Requires that QEMU be permitted to use locked memory +# for guest RAM pages. +# Defaults to false. (Since 7.1) +# # @block-bitmap-mapping: Maps block nodes and bitmaps on them to # aliases for the purpose of dirty bitmap migration. Such # aliases may for example be the corresponding names on the @@ -1158,6 +1181,7 @@ '*multifd-compression': 'MultiFDCompression', '*multifd-zlib-level': 'uint8', '*multifd-zstd-level': 'uint8', + '*zero-copy-send': { 'type': 'bool', 'if': 'CONFIG_LINUX' }, '*block-bitmap-mapping': [ 'BitmapMigrationNodeAlias' ] } } ## -- cgit v1.1