-----BEGIN PGP SIGNATURE----- iQIcBAABCAAGBQJbFLygAAoJEPSH7xhYctcjszUP/j7/21sHXwPyB5y4CQHsivLL 18MnXTkjgSlue3fuPKI9ZzD2VZq19AtwarLuW3IFf15adKfeV0hhZsIMUmu0XTAz jgol8YYgoYlk3/on8Ux8PWV9RWKHh7vWAF7hjwJOnI5CFF7gXz6kVjUx03A7RSnB 1a92lvgl5P8AbK5HZ/i08nOaAxCUWIVIoQeZf3BlZ5WdJE0j+d0Mvp/S8NEq5VPD P6oYJZy64QFGotmV1vtYD4G/Hqe8XBw2LoSVgjPSmQpd1m4CXiq0iyCxtC8HT+iq 0P0eHATRglc5oGhRV6Mi5ixH2K2MvpshdyMKVAbkJchKBHn4k3m6jefhnUXuucwC fq9x7VIYzQ80S+44wJri683yUWP3Qmbb6mWYBb1L0jgbTkY1wx431IYMtDVv5q4R oXtbe77G6lWKHH0SFrU8TY/fqJvBwpat+QwOoNsluHVjzAzpOpcVokB8pLj592/1 bHkDwvv7i+B37muOF3PFy++BoliwpRiNbVC5Btw4mnbOoY+AeJHMRBuhJHU6EyJv GOFiQ5w5XEXEu98giNqHcc0AC8w7iTRGI472UzpS0AG20wpc1/2jF0yM99stauwD oIu3MU4dQlz6QRy8KFnJShqjYNYuOs59USLiYM79ABa9J+JxJxxTAaqRbUFojQR6 KN2i0QQJ+6MO4Skjbu/3 =K0eJ -----END PGP SIGNATURE----- Merge remote-tracking branch 'remotes/juanquintela/tags/migration/20180604' into staging migration/next for 20180604 # gpg: Signature made Mon 04 Jun 2018 05:14:24 BST # gpg: using RSA key F487EF185872D723 # gpg: Good signature from "Juan Quintela <quintela@redhat.com>" # gpg: aka "Juan Quintela <quintela@trasno.org>" # Primary key fingerprint: 1899 FF8E DEBF 58CC EE03 4B82 F487 EF18 5872 D723 * remotes/juanquintela/tags/migration/20180604: migration: not wait RDMA_CM_EVENT_DISCONNECTED event after rdma_disconnect migration: remove unnecessary variables len in QIOChannelRDMA migration: Don't activate block devices if using -S migration: discard non-migratable RAMBlocks migration: introduce decompress-error-check Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
3577 lines
102 KiB
C
3577 lines
102 KiB
C
/*
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* QEMU System Emulator
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*
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* Copyright (c) 2003-2008 Fabrice Bellard
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* Copyright (c) 2011-2015 Red Hat Inc
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*
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* Authors:
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* Juan Quintela <quintela@redhat.com>
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*
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* Permission is hereby granted, free of charge, to any person obtaining a copy
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* of this software and associated documentation files (the "Software"), to deal
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* in the Software without restriction, including without limitation the rights
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* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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* copies of the Software, and to permit persons to whom the Software is
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* furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice shall be included in
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* all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
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* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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* THE SOFTWARE.
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*/
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#include "qemu/osdep.h"
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#include "cpu.h"
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#include <zlib.h>
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#include "qemu/cutils.h"
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#include "qemu/bitops.h"
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#include "qemu/bitmap.h"
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#include "qemu/main-loop.h"
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#include "xbzrle.h"
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#include "ram.h"
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#include "migration.h"
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#include "socket.h"
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#include "migration/register.h"
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#include "migration/misc.h"
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#include "qemu-file.h"
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#include "postcopy-ram.h"
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#include "page_cache.h"
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#include "qemu/error-report.h"
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#include "qapi/error.h"
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#include "qapi/qapi-events-migration.h"
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#include "qapi/qmp/qerror.h"
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#include "trace.h"
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#include "exec/ram_addr.h"
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#include "exec/target_page.h"
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#include "qemu/rcu_queue.h"
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#include "migration/colo.h"
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#include "block.h"
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#include "sysemu/sysemu.h"
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#include "qemu/uuid.h"
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#include "savevm.h"
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/***********************************************************/
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/* ram save/restore */
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/* RAM_SAVE_FLAG_ZERO used to be named RAM_SAVE_FLAG_COMPRESS, it
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* worked for pages that where filled with the same char. We switched
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* it to only search for the zero value. And to avoid confusion with
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* RAM_SSAVE_FLAG_COMPRESS_PAGE just rename it.
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*/
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#define RAM_SAVE_FLAG_FULL 0x01 /* Obsolete, not used anymore */
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#define RAM_SAVE_FLAG_ZERO 0x02
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#define RAM_SAVE_FLAG_MEM_SIZE 0x04
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#define RAM_SAVE_FLAG_PAGE 0x08
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#define RAM_SAVE_FLAG_EOS 0x10
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#define RAM_SAVE_FLAG_CONTINUE 0x20
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#define RAM_SAVE_FLAG_XBZRLE 0x40
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/* 0x80 is reserved in migration.h start with 0x100 next */
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#define RAM_SAVE_FLAG_COMPRESS_PAGE 0x100
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static inline bool is_zero_range(uint8_t *p, uint64_t size)
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{
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return buffer_is_zero(p, size);
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}
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XBZRLECacheStats xbzrle_counters;
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/* struct contains XBZRLE cache and a static page
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used by the compression */
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static struct {
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/* buffer used for XBZRLE encoding */
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uint8_t *encoded_buf;
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/* buffer for storing page content */
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uint8_t *current_buf;
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/* Cache for XBZRLE, Protected by lock. */
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PageCache *cache;
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QemuMutex lock;
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/* it will store a page full of zeros */
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uint8_t *zero_target_page;
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/* buffer used for XBZRLE decoding */
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uint8_t *decoded_buf;
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} XBZRLE;
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static void XBZRLE_cache_lock(void)
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{
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if (migrate_use_xbzrle())
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qemu_mutex_lock(&XBZRLE.lock);
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}
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static void XBZRLE_cache_unlock(void)
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{
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if (migrate_use_xbzrle())
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qemu_mutex_unlock(&XBZRLE.lock);
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}
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/**
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* xbzrle_cache_resize: resize the xbzrle cache
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*
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* This function is called from qmp_migrate_set_cache_size in main
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* thread, possibly while a migration is in progress. A running
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* migration may be using the cache and might finish during this call,
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* hence changes to the cache are protected by XBZRLE.lock().
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*
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* Returns 0 for success or -1 for error
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*
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* @new_size: new cache size
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* @errp: set *errp if the check failed, with reason
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*/
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int xbzrle_cache_resize(int64_t new_size, Error **errp)
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{
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PageCache *new_cache;
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int64_t ret = 0;
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/* Check for truncation */
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if (new_size != (size_t)new_size) {
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error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "cache size",
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"exceeding address space");
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return -1;
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}
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if (new_size == migrate_xbzrle_cache_size()) {
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/* nothing to do */
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return 0;
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}
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XBZRLE_cache_lock();
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if (XBZRLE.cache != NULL) {
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new_cache = cache_init(new_size, TARGET_PAGE_SIZE, errp);
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if (!new_cache) {
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ret = -1;
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goto out;
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}
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cache_fini(XBZRLE.cache);
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XBZRLE.cache = new_cache;
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}
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out:
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XBZRLE_cache_unlock();
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return ret;
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}
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/* Should be holding either ram_list.mutex, or the RCU lock. */
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#define RAMBLOCK_FOREACH_MIGRATABLE(block) \
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RAMBLOCK_FOREACH(block) \
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if (!qemu_ram_is_migratable(block)) {} else
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static void ramblock_recv_map_init(void)
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{
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RAMBlock *rb;
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RAMBLOCK_FOREACH_MIGRATABLE(rb) {
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assert(!rb->receivedmap);
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rb->receivedmap = bitmap_new(rb->max_length >> qemu_target_page_bits());
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}
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}
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int ramblock_recv_bitmap_test(RAMBlock *rb, void *host_addr)
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{
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return test_bit(ramblock_recv_bitmap_offset(host_addr, rb),
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rb->receivedmap);
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}
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bool ramblock_recv_bitmap_test_byte_offset(RAMBlock *rb, uint64_t byte_offset)
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{
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return test_bit(byte_offset >> TARGET_PAGE_BITS, rb->receivedmap);
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}
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void ramblock_recv_bitmap_set(RAMBlock *rb, void *host_addr)
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{
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set_bit_atomic(ramblock_recv_bitmap_offset(host_addr, rb), rb->receivedmap);
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}
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void ramblock_recv_bitmap_set_range(RAMBlock *rb, void *host_addr,
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size_t nr)
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{
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bitmap_set_atomic(rb->receivedmap,
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ramblock_recv_bitmap_offset(host_addr, rb),
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nr);
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}
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#define RAMBLOCK_RECV_BITMAP_ENDING (0x0123456789abcdefULL)
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/*
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* Format: bitmap_size (8 bytes) + whole_bitmap (N bytes).
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*
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* Returns >0 if success with sent bytes, or <0 if error.
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*/
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int64_t ramblock_recv_bitmap_send(QEMUFile *file,
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const char *block_name)
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{
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RAMBlock *block = qemu_ram_block_by_name(block_name);
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unsigned long *le_bitmap, nbits;
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uint64_t size;
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if (!block) {
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error_report("%s: invalid block name: %s", __func__, block_name);
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return -1;
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}
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nbits = block->used_length >> TARGET_PAGE_BITS;
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/*
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* Make sure the tmp bitmap buffer is big enough, e.g., on 32bit
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* machines we may need 4 more bytes for padding (see below
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* comment). So extend it a bit before hand.
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*/
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le_bitmap = bitmap_new(nbits + BITS_PER_LONG);
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/*
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* Always use little endian when sending the bitmap. This is
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* required that when source and destination VMs are not using the
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* same endianess. (Note: big endian won't work.)
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*/
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bitmap_to_le(le_bitmap, block->receivedmap, nbits);
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/* Size of the bitmap, in bytes */
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size = nbits / 8;
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/*
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* size is always aligned to 8 bytes for 64bit machines, but it
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* may not be true for 32bit machines. We need this padding to
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* make sure the migration can survive even between 32bit and
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* 64bit machines.
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*/
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size = ROUND_UP(size, 8);
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qemu_put_be64(file, size);
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qemu_put_buffer(file, (const uint8_t *)le_bitmap, size);
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/*
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* Mark as an end, in case the middle part is screwed up due to
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* some "misterious" reason.
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*/
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qemu_put_be64(file, RAMBLOCK_RECV_BITMAP_ENDING);
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qemu_fflush(file);
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g_free(le_bitmap);
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if (qemu_file_get_error(file)) {
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return qemu_file_get_error(file);
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}
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return size + sizeof(size);
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}
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/*
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* An outstanding page request, on the source, having been received
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* and queued
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*/
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struct RAMSrcPageRequest {
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RAMBlock *rb;
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hwaddr offset;
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hwaddr len;
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QSIMPLEQ_ENTRY(RAMSrcPageRequest) next_req;
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};
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/* State of RAM for migration */
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struct RAMState {
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/* QEMUFile used for this migration */
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QEMUFile *f;
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/* Last block that we have visited searching for dirty pages */
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RAMBlock *last_seen_block;
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/* Last block from where we have sent data */
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RAMBlock *last_sent_block;
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/* Last dirty target page we have sent */
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ram_addr_t last_page;
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/* last ram version we have seen */
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uint32_t last_version;
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/* We are in the first round */
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bool ram_bulk_stage;
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/* How many times we have dirty too many pages */
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int dirty_rate_high_cnt;
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/* these variables are used for bitmap sync */
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/* last time we did a full bitmap_sync */
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int64_t time_last_bitmap_sync;
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/* bytes transferred at start_time */
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uint64_t bytes_xfer_prev;
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/* number of dirty pages since start_time */
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uint64_t num_dirty_pages_period;
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/* xbzrle misses since the beginning of the period */
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uint64_t xbzrle_cache_miss_prev;
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/* number of iterations at the beginning of period */
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uint64_t iterations_prev;
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/* Iterations since start */
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uint64_t iterations;
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/* number of dirty bits in the bitmap */
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uint64_t migration_dirty_pages;
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/* protects modification of the bitmap */
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QemuMutex bitmap_mutex;
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/* The RAMBlock used in the last src_page_requests */
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RAMBlock *last_req_rb;
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/* Queue of outstanding page requests from the destination */
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QemuMutex src_page_req_mutex;
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QSIMPLEQ_HEAD(src_page_requests, RAMSrcPageRequest) src_page_requests;
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};
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typedef struct RAMState RAMState;
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static RAMState *ram_state;
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uint64_t ram_bytes_remaining(void)
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{
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return ram_state ? (ram_state->migration_dirty_pages * TARGET_PAGE_SIZE) :
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0;
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}
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MigrationStats ram_counters;
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/* used by the search for pages to send */
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struct PageSearchStatus {
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/* Current block being searched */
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RAMBlock *block;
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/* Current page to search from */
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unsigned long page;
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/* Set once we wrap around */
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bool complete_round;
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};
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typedef struct PageSearchStatus PageSearchStatus;
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struct CompressParam {
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bool done;
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bool quit;
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QEMUFile *file;
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QemuMutex mutex;
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QemuCond cond;
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RAMBlock *block;
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ram_addr_t offset;
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/* internally used fields */
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z_stream stream;
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uint8_t *originbuf;
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};
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typedef struct CompressParam CompressParam;
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struct DecompressParam {
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bool done;
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bool quit;
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QemuMutex mutex;
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QemuCond cond;
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void *des;
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uint8_t *compbuf;
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int len;
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z_stream stream;
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};
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typedef struct DecompressParam DecompressParam;
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static CompressParam *comp_param;
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static QemuThread *compress_threads;
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/* comp_done_cond is used to wake up the migration thread when
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* one of the compression threads has finished the compression.
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* comp_done_lock is used to co-work with comp_done_cond.
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*/
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static QemuMutex comp_done_lock;
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static QemuCond comp_done_cond;
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/* The empty QEMUFileOps will be used by file in CompressParam */
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static const QEMUFileOps empty_ops = { };
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static QEMUFile *decomp_file;
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static DecompressParam *decomp_param;
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static QemuThread *decompress_threads;
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static QemuMutex decomp_done_lock;
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static QemuCond decomp_done_cond;
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static int do_compress_ram_page(QEMUFile *f, z_stream *stream, RAMBlock *block,
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ram_addr_t offset, uint8_t *source_buf);
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static void *do_data_compress(void *opaque)
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{
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CompressParam *param = opaque;
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RAMBlock *block;
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ram_addr_t offset;
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qemu_mutex_lock(¶m->mutex);
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while (!param->quit) {
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if (param->block) {
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block = param->block;
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offset = param->offset;
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param->block = NULL;
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qemu_mutex_unlock(¶m->mutex);
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do_compress_ram_page(param->file, ¶m->stream, block, offset,
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param->originbuf);
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qemu_mutex_lock(&comp_done_lock);
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param->done = true;
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qemu_cond_signal(&comp_done_cond);
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qemu_mutex_unlock(&comp_done_lock);
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|
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qemu_mutex_lock(¶m->mutex);
|
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} else {
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qemu_cond_wait(¶m->cond, ¶m->mutex);
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}
|
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}
|
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qemu_mutex_unlock(¶m->mutex);
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|
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return NULL;
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}
|
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|
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static inline void terminate_compression_threads(void)
|
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{
|
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int idx, thread_count;
|
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|
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thread_count = migrate_compress_threads();
|
|
|
|
for (idx = 0; idx < thread_count; idx++) {
|
|
qemu_mutex_lock(&comp_param[idx].mutex);
|
|
comp_param[idx].quit = true;
|
|
qemu_cond_signal(&comp_param[idx].cond);
|
|
qemu_mutex_unlock(&comp_param[idx].mutex);
|
|
}
|
|
}
|
|
|
|
static void compress_threads_save_cleanup(void)
|
|
{
|
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int i, thread_count;
|
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|
|
if (!migrate_use_compression()) {
|
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return;
|
|
}
|
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terminate_compression_threads();
|
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thread_count = migrate_compress_threads();
|
|
for (i = 0; i < thread_count; i++) {
|
|
/*
|
|
* we use it as a indicator which shows if the thread is
|
|
* properly init'd or not
|
|
*/
|
|
if (!comp_param[i].file) {
|
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break;
|
|
}
|
|
qemu_thread_join(compress_threads + i);
|
|
qemu_mutex_destroy(&comp_param[i].mutex);
|
|
qemu_cond_destroy(&comp_param[i].cond);
|
|
deflateEnd(&comp_param[i].stream);
|
|
g_free(comp_param[i].originbuf);
|
|
qemu_fclose(comp_param[i].file);
|
|
comp_param[i].file = NULL;
|
|
}
|
|
qemu_mutex_destroy(&comp_done_lock);
|
|
qemu_cond_destroy(&comp_done_cond);
|
|
g_free(compress_threads);
|
|
g_free(comp_param);
|
|
compress_threads = NULL;
|
|
comp_param = NULL;
|
|
}
|
|
|
|
static int compress_threads_save_setup(void)
|
|
{
|
|
int i, thread_count;
|
|
|
|
if (!migrate_use_compression()) {
|
|
return 0;
|
|
}
|
|
thread_count = migrate_compress_threads();
|
|
compress_threads = g_new0(QemuThread, thread_count);
|
|
comp_param = g_new0(CompressParam, thread_count);
|
|
qemu_cond_init(&comp_done_cond);
|
|
qemu_mutex_init(&comp_done_lock);
|
|
for (i = 0; i < thread_count; i++) {
|
|
comp_param[i].originbuf = g_try_malloc(TARGET_PAGE_SIZE);
|
|
if (!comp_param[i].originbuf) {
|
|
goto exit;
|
|
}
|
|
|
|
if (deflateInit(&comp_param[i].stream,
|
|
migrate_compress_level()) != Z_OK) {
|
|
g_free(comp_param[i].originbuf);
|
|
goto exit;
|
|
}
|
|
|
|
/* comp_param[i].file is just used as a dummy buffer to save data,
|
|
* set its ops to empty.
|
|
*/
|
|
comp_param[i].file = qemu_fopen_ops(NULL, &empty_ops);
|
|
comp_param[i].done = true;
|
|
comp_param[i].quit = false;
|
|
qemu_mutex_init(&comp_param[i].mutex);
|
|
qemu_cond_init(&comp_param[i].cond);
|
|
qemu_thread_create(compress_threads + i, "compress",
|
|
do_data_compress, comp_param + i,
|
|
QEMU_THREAD_JOINABLE);
|
|
}
|
|
return 0;
|
|
|
|
exit:
|
|
compress_threads_save_cleanup();
|
|
return -1;
|
|
}
|
|
|
|
/* Multiple fd's */
|
|
|
|
#define MULTIFD_MAGIC 0x11223344U
|
|
#define MULTIFD_VERSION 1
|
|
|
|
typedef struct {
|
|
uint32_t magic;
|
|
uint32_t version;
|
|
unsigned char uuid[16]; /* QemuUUID */
|
|
uint8_t id;
|
|
} __attribute__((packed)) MultiFDInit_t;
|
|
|
|
typedef struct {
|
|
/* this fields are not changed once the thread is created */
|
|
/* channel number */
|
|
uint8_t id;
|
|
/* channel thread name */
|
|
char *name;
|
|
/* channel thread id */
|
|
QemuThread thread;
|
|
/* communication channel */
|
|
QIOChannel *c;
|
|
/* sem where to wait for more work */
|
|
QemuSemaphore sem;
|
|
/* this mutex protects the following parameters */
|
|
QemuMutex mutex;
|
|
/* is this channel thread running */
|
|
bool running;
|
|
/* should this thread finish */
|
|
bool quit;
|
|
} MultiFDSendParams;
|
|
|
|
typedef struct {
|
|
/* this fields are not changed once the thread is created */
|
|
/* channel number */
|
|
uint8_t id;
|
|
/* channel thread name */
|
|
char *name;
|
|
/* channel thread id */
|
|
QemuThread thread;
|
|
/* communication channel */
|
|
QIOChannel *c;
|
|
/* sem where to wait for more work */
|
|
QemuSemaphore sem;
|
|
/* this mutex protects the following parameters */
|
|
QemuMutex mutex;
|
|
/* is this channel thread running */
|
|
bool running;
|
|
/* should this thread finish */
|
|
bool quit;
|
|
} MultiFDRecvParams;
|
|
|
|
static int multifd_send_initial_packet(MultiFDSendParams *p, Error **errp)
|
|
{
|
|
MultiFDInit_t msg;
|
|
int ret;
|
|
|
|
msg.magic = cpu_to_be32(MULTIFD_MAGIC);
|
|
msg.version = cpu_to_be32(MULTIFD_VERSION);
|
|
msg.id = p->id;
|
|
memcpy(msg.uuid, &qemu_uuid.data, sizeof(msg.uuid));
|
|
|
|
ret = qio_channel_write_all(p->c, (char *)&msg, sizeof(msg), errp);
|
|
if (ret != 0) {
|
|
return -1;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int multifd_recv_initial_packet(QIOChannel *c, Error **errp)
|
|
{
|
|
MultiFDInit_t msg;
|
|
int ret;
|
|
|
|
ret = qio_channel_read_all(c, (char *)&msg, sizeof(msg), errp);
|
|
if (ret != 0) {
|
|
return -1;
|
|
}
|
|
|
|
be32_to_cpus(&msg.magic);
|
|
be32_to_cpus(&msg.version);
|
|
|
|
if (msg.magic != MULTIFD_MAGIC) {
|
|
error_setg(errp, "multifd: received packet magic %x "
|
|
"expected %x", msg.magic, MULTIFD_MAGIC);
|
|
return -1;
|
|
}
|
|
|
|
if (msg.version != MULTIFD_VERSION) {
|
|
error_setg(errp, "multifd: received packet version %d "
|
|
"expected %d", msg.version, MULTIFD_VERSION);
|
|
return -1;
|
|
}
|
|
|
|
if (memcmp(msg.uuid, &qemu_uuid, sizeof(qemu_uuid))) {
|
|
char *uuid = qemu_uuid_unparse_strdup(&qemu_uuid);
|
|
char *msg_uuid = qemu_uuid_unparse_strdup((const QemuUUID *)msg.uuid);
|
|
|
|
error_setg(errp, "multifd: received uuid '%s' and expected "
|
|
"uuid '%s' for channel %hhd", msg_uuid, uuid, msg.id);
|
|
g_free(uuid);
|
|
g_free(msg_uuid);
|
|
return -1;
|
|
}
|
|
|
|
if (msg.id > migrate_multifd_channels()) {
|
|
error_setg(errp, "multifd: received channel version %d "
|
|
"expected %d", msg.version, MULTIFD_VERSION);
|
|
return -1;
|
|
}
|
|
|
|
return msg.id;
|
|
}
|
|
|
|
struct {
|
|
MultiFDSendParams *params;
|
|
/* number of created threads */
|
|
int count;
|
|
} *multifd_send_state;
|
|
|
|
static void multifd_send_terminate_threads(Error *err)
|
|
{
|
|
int i;
|
|
|
|
if (err) {
|
|
MigrationState *s = migrate_get_current();
|
|
migrate_set_error(s, err);
|
|
if (s->state == MIGRATION_STATUS_SETUP ||
|
|
s->state == MIGRATION_STATUS_PRE_SWITCHOVER ||
|
|
s->state == MIGRATION_STATUS_DEVICE ||
|
|
s->state == MIGRATION_STATUS_ACTIVE) {
|
|
migrate_set_state(&s->state, s->state,
|
|
MIGRATION_STATUS_FAILED);
|
|
}
|
|
}
|
|
|
|
for (i = 0; i < migrate_multifd_channels(); i++) {
|
|
MultiFDSendParams *p = &multifd_send_state->params[i];
|
|
|
|
qemu_mutex_lock(&p->mutex);
|
|
p->quit = true;
|
|
qemu_sem_post(&p->sem);
|
|
qemu_mutex_unlock(&p->mutex);
|
|
}
|
|
}
|
|
|
|
int multifd_save_cleanup(Error **errp)
|
|
{
|
|
int i;
|
|
int ret = 0;
|
|
|
|
if (!migrate_use_multifd()) {
|
|
return 0;
|
|
}
|
|
multifd_send_terminate_threads(NULL);
|
|
for (i = 0; i < migrate_multifd_channels(); i++) {
|
|
MultiFDSendParams *p = &multifd_send_state->params[i];
|
|
|
|
if (p->running) {
|
|
qemu_thread_join(&p->thread);
|
|
}
|
|
socket_send_channel_destroy(p->c);
|
|
p->c = NULL;
|
|
qemu_mutex_destroy(&p->mutex);
|
|
qemu_sem_destroy(&p->sem);
|
|
g_free(p->name);
|
|
p->name = NULL;
|
|
}
|
|
g_free(multifd_send_state->params);
|
|
multifd_send_state->params = NULL;
|
|
g_free(multifd_send_state);
|
|
multifd_send_state = NULL;
|
|
return ret;
|
|
}
|
|
|
|
static void *multifd_send_thread(void *opaque)
|
|
{
|
|
MultiFDSendParams *p = opaque;
|
|
Error *local_err = NULL;
|
|
|
|
if (multifd_send_initial_packet(p, &local_err) < 0) {
|
|
goto out;
|
|
}
|
|
|
|
while (true) {
|
|
qemu_mutex_lock(&p->mutex);
|
|
if (p->quit) {
|
|
qemu_mutex_unlock(&p->mutex);
|
|
break;
|
|
}
|
|
qemu_mutex_unlock(&p->mutex);
|
|
qemu_sem_wait(&p->sem);
|
|
}
|
|
|
|
out:
|
|
if (local_err) {
|
|
multifd_send_terminate_threads(local_err);
|
|
}
|
|
|
|
qemu_mutex_lock(&p->mutex);
|
|
p->running = false;
|
|
qemu_mutex_unlock(&p->mutex);
|
|
|
|
return NULL;
|
|
}
|
|
|
|
static void multifd_new_send_channel_async(QIOTask *task, gpointer opaque)
|
|
{
|
|
MultiFDSendParams *p = opaque;
|
|
QIOChannel *sioc = QIO_CHANNEL(qio_task_get_source(task));
|
|
Error *local_err = NULL;
|
|
|
|
if (qio_task_propagate_error(task, &local_err)) {
|
|
if (multifd_save_cleanup(&local_err) != 0) {
|
|
migrate_set_error(migrate_get_current(), local_err);
|
|
}
|
|
} else {
|
|
p->c = QIO_CHANNEL(sioc);
|
|
qio_channel_set_delay(p->c, false);
|
|
p->running = true;
|
|
qemu_thread_create(&p->thread, p->name, multifd_send_thread, p,
|
|
QEMU_THREAD_JOINABLE);
|
|
|
|
atomic_inc(&multifd_send_state->count);
|
|
}
|
|
}
|
|
|
|
int multifd_save_setup(void)
|
|
{
|
|
int thread_count;
|
|
uint8_t i;
|
|
|
|
if (!migrate_use_multifd()) {
|
|
return 0;
|
|
}
|
|
thread_count = migrate_multifd_channels();
|
|
multifd_send_state = g_malloc0(sizeof(*multifd_send_state));
|
|
multifd_send_state->params = g_new0(MultiFDSendParams, thread_count);
|
|
atomic_set(&multifd_send_state->count, 0);
|
|
for (i = 0; i < thread_count; i++) {
|
|
MultiFDSendParams *p = &multifd_send_state->params[i];
|
|
|
|
qemu_mutex_init(&p->mutex);
|
|
qemu_sem_init(&p->sem, 0);
|
|
p->quit = false;
|
|
p->id = i;
|
|
p->name = g_strdup_printf("multifdsend_%d", i);
|
|
socket_send_channel_create(multifd_new_send_channel_async, p);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
struct {
|
|
MultiFDRecvParams *params;
|
|
/* number of created threads */
|
|
int count;
|
|
} *multifd_recv_state;
|
|
|
|
static void multifd_recv_terminate_threads(Error *err)
|
|
{
|
|
int i;
|
|
|
|
if (err) {
|
|
MigrationState *s = migrate_get_current();
|
|
migrate_set_error(s, err);
|
|
if (s->state == MIGRATION_STATUS_SETUP ||
|
|
s->state == MIGRATION_STATUS_ACTIVE) {
|
|
migrate_set_state(&s->state, s->state,
|
|
MIGRATION_STATUS_FAILED);
|
|
}
|
|
}
|
|
|
|
for (i = 0; i < migrate_multifd_channels(); i++) {
|
|
MultiFDRecvParams *p = &multifd_recv_state->params[i];
|
|
|
|
qemu_mutex_lock(&p->mutex);
|
|
p->quit = true;
|
|
qemu_sem_post(&p->sem);
|
|
qemu_mutex_unlock(&p->mutex);
|
|
}
|
|
}
|
|
|
|
int multifd_load_cleanup(Error **errp)
|
|
{
|
|
int i;
|
|
int ret = 0;
|
|
|
|
if (!migrate_use_multifd()) {
|
|
return 0;
|
|
}
|
|
multifd_recv_terminate_threads(NULL);
|
|
for (i = 0; i < migrate_multifd_channels(); i++) {
|
|
MultiFDRecvParams *p = &multifd_recv_state->params[i];
|
|
|
|
if (p->running) {
|
|
qemu_thread_join(&p->thread);
|
|
}
|
|
object_unref(OBJECT(p->c));
|
|
p->c = NULL;
|
|
qemu_mutex_destroy(&p->mutex);
|
|
qemu_sem_destroy(&p->sem);
|
|
g_free(p->name);
|
|
p->name = NULL;
|
|
}
|
|
g_free(multifd_recv_state->params);
|
|
multifd_recv_state->params = NULL;
|
|
g_free(multifd_recv_state);
|
|
multifd_recv_state = NULL;
|
|
|
|
return ret;
|
|
}
|
|
|
|
static void *multifd_recv_thread(void *opaque)
|
|
{
|
|
MultiFDRecvParams *p = opaque;
|
|
|
|
while (true) {
|
|
qemu_mutex_lock(&p->mutex);
|
|
if (p->quit) {
|
|
qemu_mutex_unlock(&p->mutex);
|
|
break;
|
|
}
|
|
qemu_mutex_unlock(&p->mutex);
|
|
qemu_sem_wait(&p->sem);
|
|
}
|
|
|
|
qemu_mutex_lock(&p->mutex);
|
|
p->running = false;
|
|
qemu_mutex_unlock(&p->mutex);
|
|
|
|
return NULL;
|
|
}
|
|
|
|
int multifd_load_setup(void)
|
|
{
|
|
int thread_count;
|
|
uint8_t i;
|
|
|
|
if (!migrate_use_multifd()) {
|
|
return 0;
|
|
}
|
|
thread_count = migrate_multifd_channels();
|
|
multifd_recv_state = g_malloc0(sizeof(*multifd_recv_state));
|
|
multifd_recv_state->params = g_new0(MultiFDRecvParams, thread_count);
|
|
atomic_set(&multifd_recv_state->count, 0);
|
|
for (i = 0; i < thread_count; i++) {
|
|
MultiFDRecvParams *p = &multifd_recv_state->params[i];
|
|
|
|
qemu_mutex_init(&p->mutex);
|
|
qemu_sem_init(&p->sem, 0);
|
|
p->quit = false;
|
|
p->id = i;
|
|
p->name = g_strdup_printf("multifdrecv_%d", i);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
bool multifd_recv_all_channels_created(void)
|
|
{
|
|
int thread_count = migrate_multifd_channels();
|
|
|
|
if (!migrate_use_multifd()) {
|
|
return true;
|
|
}
|
|
|
|
return thread_count == atomic_read(&multifd_recv_state->count);
|
|
}
|
|
|
|
void multifd_recv_new_channel(QIOChannel *ioc)
|
|
{
|
|
MultiFDRecvParams *p;
|
|
Error *local_err = NULL;
|
|
int id;
|
|
|
|
id = multifd_recv_initial_packet(ioc, &local_err);
|
|
if (id < 0) {
|
|
multifd_recv_terminate_threads(local_err);
|
|
return;
|
|
}
|
|
|
|
p = &multifd_recv_state->params[id];
|
|
if (p->c != NULL) {
|
|
error_setg(&local_err, "multifd: received id '%d' already setup'",
|
|
id);
|
|
multifd_recv_terminate_threads(local_err);
|
|
return;
|
|
}
|
|
p->c = ioc;
|
|
object_ref(OBJECT(ioc));
|
|
|
|
p->running = true;
|
|
qemu_thread_create(&p->thread, p->name, multifd_recv_thread, p,
|
|
QEMU_THREAD_JOINABLE);
|
|
atomic_inc(&multifd_recv_state->count);
|
|
if (multifd_recv_state->count == migrate_multifd_channels()) {
|
|
migration_incoming_process();
|
|
}
|
|
}
|
|
|
|
/**
|
|
* save_page_header: write page header to wire
|
|
*
|
|
* If this is the 1st block, it also writes the block identification
|
|
*
|
|
* Returns the number of bytes written
|
|
*
|
|
* @f: QEMUFile where to send the data
|
|
* @block: block that contains the page we want to send
|
|
* @offset: offset inside the block for the page
|
|
* in the lower bits, it contains flags
|
|
*/
|
|
static size_t save_page_header(RAMState *rs, QEMUFile *f, RAMBlock *block,
|
|
ram_addr_t offset)
|
|
{
|
|
size_t size, len;
|
|
|
|
if (block == rs->last_sent_block) {
|
|
offset |= RAM_SAVE_FLAG_CONTINUE;
|
|
}
|
|
qemu_put_be64(f, offset);
|
|
size = 8;
|
|
|
|
if (!(offset & RAM_SAVE_FLAG_CONTINUE)) {
|
|
len = strlen(block->idstr);
|
|
qemu_put_byte(f, len);
|
|
qemu_put_buffer(f, (uint8_t *)block->idstr, len);
|
|
size += 1 + len;
|
|
rs->last_sent_block = block;
|
|
}
|
|
return size;
|
|
}
|
|
|
|
/**
|
|
* mig_throttle_guest_down: throotle down the guest
|
|
*
|
|
* Reduce amount of guest cpu execution to hopefully slow down memory
|
|
* writes. If guest dirty memory rate is reduced below the rate at
|
|
* which we can transfer pages to the destination then we should be
|
|
* able to complete migration. Some workloads dirty memory way too
|
|
* fast and will not effectively converge, even with auto-converge.
|
|
*/
|
|
static void mig_throttle_guest_down(void)
|
|
{
|
|
MigrationState *s = migrate_get_current();
|
|
uint64_t pct_initial = s->parameters.cpu_throttle_initial;
|
|
uint64_t pct_icrement = s->parameters.cpu_throttle_increment;
|
|
|
|
/* We have not started throttling yet. Let's start it. */
|
|
if (!cpu_throttle_active()) {
|
|
cpu_throttle_set(pct_initial);
|
|
} else {
|
|
/* Throttling already on, just increase the rate */
|
|
cpu_throttle_set(cpu_throttle_get_percentage() + pct_icrement);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* xbzrle_cache_zero_page: insert a zero page in the XBZRLE cache
|
|
*
|
|
* @rs: current RAM state
|
|
* @current_addr: address for the zero page
|
|
*
|
|
* Update the xbzrle cache to reflect a page that's been sent as all 0.
|
|
* The important thing is that a stale (not-yet-0'd) page be replaced
|
|
* by the new data.
|
|
* As a bonus, if the page wasn't in the cache it gets added so that
|
|
* when a small write is made into the 0'd page it gets XBZRLE sent.
|
|
*/
|
|
static void xbzrle_cache_zero_page(RAMState *rs, ram_addr_t current_addr)
|
|
{
|
|
if (rs->ram_bulk_stage || !migrate_use_xbzrle()) {
|
|
return;
|
|
}
|
|
|
|
/* We don't care if this fails to allocate a new cache page
|
|
* as long as it updated an old one */
|
|
cache_insert(XBZRLE.cache, current_addr, XBZRLE.zero_target_page,
|
|
ram_counters.dirty_sync_count);
|
|
}
|
|
|
|
#define ENCODING_FLAG_XBZRLE 0x1
|
|
|
|
/**
|
|
* save_xbzrle_page: compress and send current page
|
|
*
|
|
* Returns: 1 means that we wrote the page
|
|
* 0 means that page is identical to the one already sent
|
|
* -1 means that xbzrle would be longer than normal
|
|
*
|
|
* @rs: current RAM state
|
|
* @current_data: pointer to the address of the page contents
|
|
* @current_addr: addr of the page
|
|
* @block: block that contains the page we want to send
|
|
* @offset: offset inside the block for the page
|
|
* @last_stage: if we are at the completion stage
|
|
*/
|
|
static int save_xbzrle_page(RAMState *rs, uint8_t **current_data,
|
|
ram_addr_t current_addr, RAMBlock *block,
|
|
ram_addr_t offset, bool last_stage)
|
|
{
|
|
int encoded_len = 0, bytes_xbzrle;
|
|
uint8_t *prev_cached_page;
|
|
|
|
if (!cache_is_cached(XBZRLE.cache, current_addr,
|
|
ram_counters.dirty_sync_count)) {
|
|
xbzrle_counters.cache_miss++;
|
|
if (!last_stage) {
|
|
if (cache_insert(XBZRLE.cache, current_addr, *current_data,
|
|
ram_counters.dirty_sync_count) == -1) {
|
|
return -1;
|
|
} else {
|
|
/* update *current_data when the page has been
|
|
inserted into cache */
|
|
*current_data = get_cached_data(XBZRLE.cache, current_addr);
|
|
}
|
|
}
|
|
return -1;
|
|
}
|
|
|
|
prev_cached_page = get_cached_data(XBZRLE.cache, current_addr);
|
|
|
|
/* save current buffer into memory */
|
|
memcpy(XBZRLE.current_buf, *current_data, TARGET_PAGE_SIZE);
|
|
|
|
/* XBZRLE encoding (if there is no overflow) */
|
|
encoded_len = xbzrle_encode_buffer(prev_cached_page, XBZRLE.current_buf,
|
|
TARGET_PAGE_SIZE, XBZRLE.encoded_buf,
|
|
TARGET_PAGE_SIZE);
|
|
if (encoded_len == 0) {
|
|
trace_save_xbzrle_page_skipping();
|
|
return 0;
|
|
} else if (encoded_len == -1) {
|
|
trace_save_xbzrle_page_overflow();
|
|
xbzrle_counters.overflow++;
|
|
/* update data in the cache */
|
|
if (!last_stage) {
|
|
memcpy(prev_cached_page, *current_data, TARGET_PAGE_SIZE);
|
|
*current_data = prev_cached_page;
|
|
}
|
|
return -1;
|
|
}
|
|
|
|
/* we need to update the data in the cache, in order to get the same data */
|
|
if (!last_stage) {
|
|
memcpy(prev_cached_page, XBZRLE.current_buf, TARGET_PAGE_SIZE);
|
|
}
|
|
|
|
/* Send XBZRLE based compressed page */
|
|
bytes_xbzrle = save_page_header(rs, rs->f, block,
|
|
offset | RAM_SAVE_FLAG_XBZRLE);
|
|
qemu_put_byte(rs->f, ENCODING_FLAG_XBZRLE);
|
|
qemu_put_be16(rs->f, encoded_len);
|
|
qemu_put_buffer(rs->f, XBZRLE.encoded_buf, encoded_len);
|
|
bytes_xbzrle += encoded_len + 1 + 2;
|
|
xbzrle_counters.pages++;
|
|
xbzrle_counters.bytes += bytes_xbzrle;
|
|
ram_counters.transferred += bytes_xbzrle;
|
|
|
|
return 1;
|
|
}
|
|
|
|
/**
|
|
* migration_bitmap_find_dirty: find the next dirty page from start
|
|
*
|
|
* Called with rcu_read_lock() to protect migration_bitmap
|
|
*
|
|
* Returns the byte offset within memory region of the start of a dirty page
|
|
*
|
|
* @rs: current RAM state
|
|
* @rb: RAMBlock where to search for dirty pages
|
|
* @start: page where we start the search
|
|
*/
|
|
static inline
|
|
unsigned long migration_bitmap_find_dirty(RAMState *rs, RAMBlock *rb,
|
|
unsigned long start)
|
|
{
|
|
unsigned long size = rb->used_length >> TARGET_PAGE_BITS;
|
|
unsigned long *bitmap = rb->bmap;
|
|
unsigned long next;
|
|
|
|
if (!qemu_ram_is_migratable(rb)) {
|
|
return size;
|
|
}
|
|
|
|
if (rs->ram_bulk_stage && start > 0) {
|
|
next = start + 1;
|
|
} else {
|
|
next = find_next_bit(bitmap, size, start);
|
|
}
|
|
|
|
return next;
|
|
}
|
|
|
|
static inline bool migration_bitmap_clear_dirty(RAMState *rs,
|
|
RAMBlock *rb,
|
|
unsigned long page)
|
|
{
|
|
bool ret;
|
|
|
|
ret = test_and_clear_bit(page, rb->bmap);
|
|
|
|
if (ret) {
|
|
rs->migration_dirty_pages--;
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
static void migration_bitmap_sync_range(RAMState *rs, RAMBlock *rb,
|
|
ram_addr_t start, ram_addr_t length)
|
|
{
|
|
rs->migration_dirty_pages +=
|
|
cpu_physical_memory_sync_dirty_bitmap(rb, start, length,
|
|
&rs->num_dirty_pages_period);
|
|
}
|
|
|
|
/**
|
|
* ram_pagesize_summary: calculate all the pagesizes of a VM
|
|
*
|
|
* Returns a summary bitmap of the page sizes of all RAMBlocks
|
|
*
|
|
* For VMs with just normal pages this is equivalent to the host page
|
|
* size. If it's got some huge pages then it's the OR of all the
|
|
* different page sizes.
|
|
*/
|
|
uint64_t ram_pagesize_summary(void)
|
|
{
|
|
RAMBlock *block;
|
|
uint64_t summary = 0;
|
|
|
|
RAMBLOCK_FOREACH_MIGRATABLE(block) {
|
|
summary |= block->page_size;
|
|
}
|
|
|
|
return summary;
|
|
}
|
|
|
|
static void migration_bitmap_sync(RAMState *rs)
|
|
{
|
|
RAMBlock *block;
|
|
int64_t end_time;
|
|
uint64_t bytes_xfer_now;
|
|
|
|
ram_counters.dirty_sync_count++;
|
|
|
|
if (!rs->time_last_bitmap_sync) {
|
|
rs->time_last_bitmap_sync = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
|
|
}
|
|
|
|
trace_migration_bitmap_sync_start();
|
|
memory_global_dirty_log_sync();
|
|
|
|
qemu_mutex_lock(&rs->bitmap_mutex);
|
|
rcu_read_lock();
|
|
RAMBLOCK_FOREACH_MIGRATABLE(block) {
|
|
migration_bitmap_sync_range(rs, block, 0, block->used_length);
|
|
}
|
|
rcu_read_unlock();
|
|
qemu_mutex_unlock(&rs->bitmap_mutex);
|
|
|
|
trace_migration_bitmap_sync_end(rs->num_dirty_pages_period);
|
|
|
|
end_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
|
|
|
|
/* more than 1 second = 1000 millisecons */
|
|
if (end_time > rs->time_last_bitmap_sync + 1000) {
|
|
/* calculate period counters */
|
|
ram_counters.dirty_pages_rate = rs->num_dirty_pages_period * 1000
|
|
/ (end_time - rs->time_last_bitmap_sync);
|
|
bytes_xfer_now = ram_counters.transferred;
|
|
|
|
/* During block migration the auto-converge logic incorrectly detects
|
|
* that ram migration makes no progress. Avoid this by disabling the
|
|
* throttling logic during the bulk phase of block migration. */
|
|
if (migrate_auto_converge() && !blk_mig_bulk_active()) {
|
|
/* The following detection logic can be refined later. For now:
|
|
Check to see if the dirtied bytes is 50% more than the approx.
|
|
amount of bytes that just got transferred since the last time we
|
|
were in this routine. If that happens twice, start or increase
|
|
throttling */
|
|
|
|
if ((rs->num_dirty_pages_period * TARGET_PAGE_SIZE >
|
|
(bytes_xfer_now - rs->bytes_xfer_prev) / 2) &&
|
|
(++rs->dirty_rate_high_cnt >= 2)) {
|
|
trace_migration_throttle();
|
|
rs->dirty_rate_high_cnt = 0;
|
|
mig_throttle_guest_down();
|
|
}
|
|
}
|
|
|
|
if (migrate_use_xbzrle()) {
|
|
if (rs->iterations_prev != rs->iterations) {
|
|
xbzrle_counters.cache_miss_rate =
|
|
(double)(xbzrle_counters.cache_miss -
|
|
rs->xbzrle_cache_miss_prev) /
|
|
(rs->iterations - rs->iterations_prev);
|
|
}
|
|
rs->iterations_prev = rs->iterations;
|
|
rs->xbzrle_cache_miss_prev = xbzrle_counters.cache_miss;
|
|
}
|
|
|
|
/* reset period counters */
|
|
rs->time_last_bitmap_sync = end_time;
|
|
rs->num_dirty_pages_period = 0;
|
|
rs->bytes_xfer_prev = bytes_xfer_now;
|
|
}
|
|
if (migrate_use_events()) {
|
|
qapi_event_send_migration_pass(ram_counters.dirty_sync_count, NULL);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* save_zero_page: send the zero page to the stream
|
|
*
|
|
* Returns the number of pages written.
|
|
*
|
|
* @rs: current RAM state
|
|
* @block: block that contains the page we want to send
|
|
* @offset: offset inside the block for the page
|
|
*/
|
|
static int save_zero_page(RAMState *rs, RAMBlock *block, ram_addr_t offset)
|
|
{
|
|
uint8_t *p = block->host + offset;
|
|
int pages = -1;
|
|
|
|
if (is_zero_range(p, TARGET_PAGE_SIZE)) {
|
|
ram_counters.duplicate++;
|
|
ram_counters.transferred +=
|
|
save_page_header(rs, rs->f, block, offset | RAM_SAVE_FLAG_ZERO);
|
|
qemu_put_byte(rs->f, 0);
|
|
ram_counters.transferred += 1;
|
|
pages = 1;
|
|
}
|
|
|
|
return pages;
|
|
}
|
|
|
|
static void ram_release_pages(const char *rbname, uint64_t offset, int pages)
|
|
{
|
|
if (!migrate_release_ram() || !migration_in_postcopy()) {
|
|
return;
|
|
}
|
|
|
|
ram_discard_range(rbname, offset, pages << TARGET_PAGE_BITS);
|
|
}
|
|
|
|
/*
|
|
* @pages: the number of pages written by the control path,
|
|
* < 0 - error
|
|
* > 0 - number of pages written
|
|
*
|
|
* Return true if the pages has been saved, otherwise false is returned.
|
|
*/
|
|
static bool control_save_page(RAMState *rs, RAMBlock *block, ram_addr_t offset,
|
|
int *pages)
|
|
{
|
|
uint64_t bytes_xmit = 0;
|
|
int ret;
|
|
|
|
*pages = -1;
|
|
ret = ram_control_save_page(rs->f, block->offset, offset, TARGET_PAGE_SIZE,
|
|
&bytes_xmit);
|
|
if (ret == RAM_SAVE_CONTROL_NOT_SUPP) {
|
|
return false;
|
|
}
|
|
|
|
if (bytes_xmit) {
|
|
ram_counters.transferred += bytes_xmit;
|
|
*pages = 1;
|
|
}
|
|
|
|
if (ret == RAM_SAVE_CONTROL_DELAYED) {
|
|
return true;
|
|
}
|
|
|
|
if (bytes_xmit > 0) {
|
|
ram_counters.normal++;
|
|
} else if (bytes_xmit == 0) {
|
|
ram_counters.duplicate++;
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
* directly send the page to the stream
|
|
*
|
|
* Returns the number of pages written.
|
|
*
|
|
* @rs: current RAM state
|
|
* @block: block that contains the page we want to send
|
|
* @offset: offset inside the block for the page
|
|
* @buf: the page to be sent
|
|
* @async: send to page asyncly
|
|
*/
|
|
static int save_normal_page(RAMState *rs, RAMBlock *block, ram_addr_t offset,
|
|
uint8_t *buf, bool async)
|
|
{
|
|
ram_counters.transferred += save_page_header(rs, rs->f, block,
|
|
offset | RAM_SAVE_FLAG_PAGE);
|
|
if (async) {
|
|
qemu_put_buffer_async(rs->f, buf, TARGET_PAGE_SIZE,
|
|
migrate_release_ram() &
|
|
migration_in_postcopy());
|
|
} else {
|
|
qemu_put_buffer(rs->f, buf, TARGET_PAGE_SIZE);
|
|
}
|
|
ram_counters.transferred += TARGET_PAGE_SIZE;
|
|
ram_counters.normal++;
|
|
return 1;
|
|
}
|
|
|
|
/**
|
|
* ram_save_page: send the given page to the stream
|
|
*
|
|
* Returns the number of pages written.
|
|
* < 0 - error
|
|
* >=0 - Number of pages written - this might legally be 0
|
|
* if xbzrle noticed the page was the same.
|
|
*
|
|
* @rs: current RAM state
|
|
* @block: block that contains the page we want to send
|
|
* @offset: offset inside the block for the page
|
|
* @last_stage: if we are at the completion stage
|
|
*/
|
|
static int ram_save_page(RAMState *rs, PageSearchStatus *pss, bool last_stage)
|
|
{
|
|
int pages = -1;
|
|
uint8_t *p;
|
|
bool send_async = true;
|
|
RAMBlock *block = pss->block;
|
|
ram_addr_t offset = pss->page << TARGET_PAGE_BITS;
|
|
ram_addr_t current_addr = block->offset + offset;
|
|
|
|
p = block->host + offset;
|
|
trace_ram_save_page(block->idstr, (uint64_t)offset, p);
|
|
|
|
XBZRLE_cache_lock();
|
|
if (!rs->ram_bulk_stage && !migration_in_postcopy() &&
|
|
migrate_use_xbzrle()) {
|
|
pages = save_xbzrle_page(rs, &p, current_addr, block,
|
|
offset, last_stage);
|
|
if (!last_stage) {
|
|
/* Can't send this cached data async, since the cache page
|
|
* might get updated before it gets to the wire
|
|
*/
|
|
send_async = false;
|
|
}
|
|
}
|
|
|
|
/* XBZRLE overflow or normal page */
|
|
if (pages == -1) {
|
|
pages = save_normal_page(rs, block, offset, p, send_async);
|
|
}
|
|
|
|
XBZRLE_cache_unlock();
|
|
|
|
return pages;
|
|
}
|
|
|
|
static int do_compress_ram_page(QEMUFile *f, z_stream *stream, RAMBlock *block,
|
|
ram_addr_t offset, uint8_t *source_buf)
|
|
{
|
|
RAMState *rs = ram_state;
|
|
int bytes_sent, blen;
|
|
uint8_t *p = block->host + (offset & TARGET_PAGE_MASK);
|
|
|
|
bytes_sent = save_page_header(rs, f, block, offset |
|
|
RAM_SAVE_FLAG_COMPRESS_PAGE);
|
|
|
|
/*
|
|
* copy it to a internal buffer to avoid it being modified by VM
|
|
* so that we can catch up the error during compression and
|
|
* decompression
|
|
*/
|
|
memcpy(source_buf, p, TARGET_PAGE_SIZE);
|
|
blen = qemu_put_compression_data(f, stream, source_buf, TARGET_PAGE_SIZE);
|
|
if (blen < 0) {
|
|
bytes_sent = 0;
|
|
qemu_file_set_error(migrate_get_current()->to_dst_file, blen);
|
|
error_report("compressed data failed!");
|
|
} else {
|
|
bytes_sent += blen;
|
|
ram_release_pages(block->idstr, offset & TARGET_PAGE_MASK, 1);
|
|
}
|
|
|
|
return bytes_sent;
|
|
}
|
|
|
|
static void flush_compressed_data(RAMState *rs)
|
|
{
|
|
int idx, len, thread_count;
|
|
|
|
if (!migrate_use_compression()) {
|
|
return;
|
|
}
|
|
thread_count = migrate_compress_threads();
|
|
|
|
qemu_mutex_lock(&comp_done_lock);
|
|
for (idx = 0; idx < thread_count; idx++) {
|
|
while (!comp_param[idx].done) {
|
|
qemu_cond_wait(&comp_done_cond, &comp_done_lock);
|
|
}
|
|
}
|
|
qemu_mutex_unlock(&comp_done_lock);
|
|
|
|
for (idx = 0; idx < thread_count; idx++) {
|
|
qemu_mutex_lock(&comp_param[idx].mutex);
|
|
if (!comp_param[idx].quit) {
|
|
len = qemu_put_qemu_file(rs->f, comp_param[idx].file);
|
|
ram_counters.transferred += len;
|
|
}
|
|
qemu_mutex_unlock(&comp_param[idx].mutex);
|
|
}
|
|
}
|
|
|
|
static inline void set_compress_params(CompressParam *param, RAMBlock *block,
|
|
ram_addr_t offset)
|
|
{
|
|
param->block = block;
|
|
param->offset = offset;
|
|
}
|
|
|
|
static int compress_page_with_multi_thread(RAMState *rs, RAMBlock *block,
|
|
ram_addr_t offset)
|
|
{
|
|
int idx, thread_count, bytes_xmit = -1, pages = -1;
|
|
|
|
thread_count = migrate_compress_threads();
|
|
qemu_mutex_lock(&comp_done_lock);
|
|
while (true) {
|
|
for (idx = 0; idx < thread_count; idx++) {
|
|
if (comp_param[idx].done) {
|
|
comp_param[idx].done = false;
|
|
bytes_xmit = qemu_put_qemu_file(rs->f, comp_param[idx].file);
|
|
qemu_mutex_lock(&comp_param[idx].mutex);
|
|
set_compress_params(&comp_param[idx], block, offset);
|
|
qemu_cond_signal(&comp_param[idx].cond);
|
|
qemu_mutex_unlock(&comp_param[idx].mutex);
|
|
pages = 1;
|
|
ram_counters.normal++;
|
|
ram_counters.transferred += bytes_xmit;
|
|
break;
|
|
}
|
|
}
|
|
if (pages > 0) {
|
|
break;
|
|
} else {
|
|
qemu_cond_wait(&comp_done_cond, &comp_done_lock);
|
|
}
|
|
}
|
|
qemu_mutex_unlock(&comp_done_lock);
|
|
|
|
return pages;
|
|
}
|
|
|
|
/**
|
|
* find_dirty_block: find the next dirty page and update any state
|
|
* associated with the search process.
|
|
*
|
|
* Returns if a page is found
|
|
*
|
|
* @rs: current RAM state
|
|
* @pss: data about the state of the current dirty page scan
|
|
* @again: set to false if the search has scanned the whole of RAM
|
|
*/
|
|
static bool find_dirty_block(RAMState *rs, PageSearchStatus *pss, bool *again)
|
|
{
|
|
pss->page = migration_bitmap_find_dirty(rs, pss->block, pss->page);
|
|
if (pss->complete_round && pss->block == rs->last_seen_block &&
|
|
pss->page >= rs->last_page) {
|
|
/*
|
|
* We've been once around the RAM and haven't found anything.
|
|
* Give up.
|
|
*/
|
|
*again = false;
|
|
return false;
|
|
}
|
|
if ((pss->page << TARGET_PAGE_BITS) >= pss->block->used_length) {
|
|
/* Didn't find anything in this RAM Block */
|
|
pss->page = 0;
|
|
pss->block = QLIST_NEXT_RCU(pss->block, next);
|
|
if (!pss->block) {
|
|
/* Hit the end of the list */
|
|
pss->block = QLIST_FIRST_RCU(&ram_list.blocks);
|
|
/* Flag that we've looped */
|
|
pss->complete_round = true;
|
|
rs->ram_bulk_stage = false;
|
|
if (migrate_use_xbzrle()) {
|
|
/* If xbzrle is on, stop using the data compression at this
|
|
* point. In theory, xbzrle can do better than compression.
|
|
*/
|
|
flush_compressed_data(rs);
|
|
}
|
|
}
|
|
/* Didn't find anything this time, but try again on the new block */
|
|
*again = true;
|
|
return false;
|
|
} else {
|
|
/* Can go around again, but... */
|
|
*again = true;
|
|
/* We've found something so probably don't need to */
|
|
return true;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* unqueue_page: gets a page of the queue
|
|
*
|
|
* Helper for 'get_queued_page' - gets a page off the queue
|
|
*
|
|
* Returns the block of the page (or NULL if none available)
|
|
*
|
|
* @rs: current RAM state
|
|
* @offset: used to return the offset within the RAMBlock
|
|
*/
|
|
static RAMBlock *unqueue_page(RAMState *rs, ram_addr_t *offset)
|
|
{
|
|
RAMBlock *block = NULL;
|
|
|
|
qemu_mutex_lock(&rs->src_page_req_mutex);
|
|
if (!QSIMPLEQ_EMPTY(&rs->src_page_requests)) {
|
|
struct RAMSrcPageRequest *entry =
|
|
QSIMPLEQ_FIRST(&rs->src_page_requests);
|
|
block = entry->rb;
|
|
*offset = entry->offset;
|
|
|
|
if (entry->len > TARGET_PAGE_SIZE) {
|
|
entry->len -= TARGET_PAGE_SIZE;
|
|
entry->offset += TARGET_PAGE_SIZE;
|
|
} else {
|
|
memory_region_unref(block->mr);
|
|
QSIMPLEQ_REMOVE_HEAD(&rs->src_page_requests, next_req);
|
|
g_free(entry);
|
|
}
|
|
}
|
|
qemu_mutex_unlock(&rs->src_page_req_mutex);
|
|
|
|
return block;
|
|
}
|
|
|
|
/**
|
|
* get_queued_page: unqueue a page from the postocpy requests
|
|
*
|
|
* Skips pages that are already sent (!dirty)
|
|
*
|
|
* Returns if a queued page is found
|
|
*
|
|
* @rs: current RAM state
|
|
* @pss: data about the state of the current dirty page scan
|
|
*/
|
|
static bool get_queued_page(RAMState *rs, PageSearchStatus *pss)
|
|
{
|
|
RAMBlock *block;
|
|
ram_addr_t offset;
|
|
bool dirty;
|
|
|
|
do {
|
|
block = unqueue_page(rs, &offset);
|
|
/*
|
|
* We're sending this page, and since it's postcopy nothing else
|
|
* will dirty it, and we must make sure it doesn't get sent again
|
|
* even if this queue request was received after the background
|
|
* search already sent it.
|
|
*/
|
|
if (block) {
|
|
unsigned long page;
|
|
|
|
page = offset >> TARGET_PAGE_BITS;
|
|
dirty = test_bit(page, block->bmap);
|
|
if (!dirty) {
|
|
trace_get_queued_page_not_dirty(block->idstr, (uint64_t)offset,
|
|
page, test_bit(page, block->unsentmap));
|
|
} else {
|
|
trace_get_queued_page(block->idstr, (uint64_t)offset, page);
|
|
}
|
|
}
|
|
|
|
} while (block && !dirty);
|
|
|
|
if (block) {
|
|
/*
|
|
* As soon as we start servicing pages out of order, then we have
|
|
* to kill the bulk stage, since the bulk stage assumes
|
|
* in (migration_bitmap_find_and_reset_dirty) that every page is
|
|
* dirty, that's no longer true.
|
|
*/
|
|
rs->ram_bulk_stage = false;
|
|
|
|
/*
|
|
* We want the background search to continue from the queued page
|
|
* since the guest is likely to want other pages near to the page
|
|
* it just requested.
|
|
*/
|
|
pss->block = block;
|
|
pss->page = offset >> TARGET_PAGE_BITS;
|
|
}
|
|
|
|
return !!block;
|
|
}
|
|
|
|
/**
|
|
* migration_page_queue_free: drop any remaining pages in the ram
|
|
* request queue
|
|
*
|
|
* It should be empty at the end anyway, but in error cases there may
|
|
* be some left. in case that there is any page left, we drop it.
|
|
*
|
|
*/
|
|
static void migration_page_queue_free(RAMState *rs)
|
|
{
|
|
struct RAMSrcPageRequest *mspr, *next_mspr;
|
|
/* This queue generally should be empty - but in the case of a failed
|
|
* migration might have some droppings in.
|
|
*/
|
|
rcu_read_lock();
|
|
QSIMPLEQ_FOREACH_SAFE(mspr, &rs->src_page_requests, next_req, next_mspr) {
|
|
memory_region_unref(mspr->rb->mr);
|
|
QSIMPLEQ_REMOVE_HEAD(&rs->src_page_requests, next_req);
|
|
g_free(mspr);
|
|
}
|
|
rcu_read_unlock();
|
|
}
|
|
|
|
/**
|
|
* ram_save_queue_pages: queue the page for transmission
|
|
*
|
|
* A request from postcopy destination for example.
|
|
*
|
|
* Returns zero on success or negative on error
|
|
*
|
|
* @rbname: Name of the RAMBLock of the request. NULL means the
|
|
* same that last one.
|
|
* @start: starting address from the start of the RAMBlock
|
|
* @len: length (in bytes) to send
|
|
*/
|
|
int ram_save_queue_pages(const char *rbname, ram_addr_t start, ram_addr_t len)
|
|
{
|
|
RAMBlock *ramblock;
|
|
RAMState *rs = ram_state;
|
|
|
|
ram_counters.postcopy_requests++;
|
|
rcu_read_lock();
|
|
if (!rbname) {
|
|
/* Reuse last RAMBlock */
|
|
ramblock = rs->last_req_rb;
|
|
|
|
if (!ramblock) {
|
|
/*
|
|
* Shouldn't happen, we can't reuse the last RAMBlock if
|
|
* it's the 1st request.
|
|
*/
|
|
error_report("ram_save_queue_pages no previous block");
|
|
goto err;
|
|
}
|
|
} else {
|
|
ramblock = qemu_ram_block_by_name(rbname);
|
|
|
|
if (!ramblock) {
|
|
/* We shouldn't be asked for a non-existent RAMBlock */
|
|
error_report("ram_save_queue_pages no block '%s'", rbname);
|
|
goto err;
|
|
}
|
|
rs->last_req_rb = ramblock;
|
|
}
|
|
trace_ram_save_queue_pages(ramblock->idstr, start, len);
|
|
if (start+len > ramblock->used_length) {
|
|
error_report("%s request overrun start=" RAM_ADDR_FMT " len="
|
|
RAM_ADDR_FMT " blocklen=" RAM_ADDR_FMT,
|
|
__func__, start, len, ramblock->used_length);
|
|
goto err;
|
|
}
|
|
|
|
struct RAMSrcPageRequest *new_entry =
|
|
g_malloc0(sizeof(struct RAMSrcPageRequest));
|
|
new_entry->rb = ramblock;
|
|
new_entry->offset = start;
|
|
new_entry->len = len;
|
|
|
|
memory_region_ref(ramblock->mr);
|
|
qemu_mutex_lock(&rs->src_page_req_mutex);
|
|
QSIMPLEQ_INSERT_TAIL(&rs->src_page_requests, new_entry, next_req);
|
|
qemu_mutex_unlock(&rs->src_page_req_mutex);
|
|
rcu_read_unlock();
|
|
|
|
return 0;
|
|
|
|
err:
|
|
rcu_read_unlock();
|
|
return -1;
|
|
}
|
|
|
|
static bool save_page_use_compression(RAMState *rs)
|
|
{
|
|
if (!migrate_use_compression()) {
|
|
return false;
|
|
}
|
|
|
|
/*
|
|
* If xbzrle is on, stop using the data compression after first
|
|
* round of migration even if compression is enabled. In theory,
|
|
* xbzrle can do better than compression.
|
|
*/
|
|
if (rs->ram_bulk_stage || !migrate_use_xbzrle()) {
|
|
return true;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
/**
|
|
* ram_save_target_page: save one target page
|
|
*
|
|
* Returns the number of pages written
|
|
*
|
|
* @rs: current RAM state
|
|
* @pss: data about the page we want to send
|
|
* @last_stage: if we are at the completion stage
|
|
*/
|
|
static int ram_save_target_page(RAMState *rs, PageSearchStatus *pss,
|
|
bool last_stage)
|
|
{
|
|
RAMBlock *block = pss->block;
|
|
ram_addr_t offset = pss->page << TARGET_PAGE_BITS;
|
|
int res;
|
|
|
|
if (control_save_page(rs, block, offset, &res)) {
|
|
return res;
|
|
}
|
|
|
|
/*
|
|
* When starting the process of a new block, the first page of
|
|
* the block should be sent out before other pages in the same
|
|
* block, and all the pages in last block should have been sent
|
|
* out, keeping this order is important, because the 'cont' flag
|
|
* is used to avoid resending the block name.
|
|
*/
|
|
if (block != rs->last_sent_block && save_page_use_compression(rs)) {
|
|
flush_compressed_data(rs);
|
|
}
|
|
|
|
res = save_zero_page(rs, block, offset);
|
|
if (res > 0) {
|
|
/* Must let xbzrle know, otherwise a previous (now 0'd) cached
|
|
* page would be stale
|
|
*/
|
|
if (!save_page_use_compression(rs)) {
|
|
XBZRLE_cache_lock();
|
|
xbzrle_cache_zero_page(rs, block->offset + offset);
|
|
XBZRLE_cache_unlock();
|
|
}
|
|
ram_release_pages(block->idstr, offset, res);
|
|
return res;
|
|
}
|
|
|
|
/*
|
|
* Make sure the first page is sent out before other pages.
|
|
*
|
|
* we post it as normal page as compression will take much
|
|
* CPU resource.
|
|
*/
|
|
if (block == rs->last_sent_block && save_page_use_compression(rs)) {
|
|
return compress_page_with_multi_thread(rs, block, offset);
|
|
}
|
|
|
|
return ram_save_page(rs, pss, last_stage);
|
|
}
|
|
|
|
/**
|
|
* ram_save_host_page: save a whole host page
|
|
*
|
|
* Starting at *offset send pages up to the end of the current host
|
|
* page. It's valid for the initial offset to point into the middle of
|
|
* a host page in which case the remainder of the hostpage is sent.
|
|
* Only dirty target pages are sent. Note that the host page size may
|
|
* be a huge page for this block.
|
|
* The saving stops at the boundary of the used_length of the block
|
|
* if the RAMBlock isn't a multiple of the host page size.
|
|
*
|
|
* Returns the number of pages written or negative on error
|
|
*
|
|
* @rs: current RAM state
|
|
* @ms: current migration state
|
|
* @pss: data about the page we want to send
|
|
* @last_stage: if we are at the completion stage
|
|
*/
|
|
static int ram_save_host_page(RAMState *rs, PageSearchStatus *pss,
|
|
bool last_stage)
|
|
{
|
|
int tmppages, pages = 0;
|
|
size_t pagesize_bits =
|
|
qemu_ram_pagesize(pss->block) >> TARGET_PAGE_BITS;
|
|
|
|
if (!qemu_ram_is_migratable(pss->block)) {
|
|
error_report("block %s should not be migrated !", pss->block->idstr);
|
|
return 0;
|
|
}
|
|
|
|
do {
|
|
/* Check the pages is dirty and if it is send it */
|
|
if (!migration_bitmap_clear_dirty(rs, pss->block, pss->page)) {
|
|
pss->page++;
|
|
continue;
|
|
}
|
|
|
|
tmppages = ram_save_target_page(rs, pss, last_stage);
|
|
if (tmppages < 0) {
|
|
return tmppages;
|
|
}
|
|
|
|
pages += tmppages;
|
|
if (pss->block->unsentmap) {
|
|
clear_bit(pss->page, pss->block->unsentmap);
|
|
}
|
|
|
|
pss->page++;
|
|
} while ((pss->page & (pagesize_bits - 1)) &&
|
|
offset_in_ramblock(pss->block, pss->page << TARGET_PAGE_BITS));
|
|
|
|
/* The offset we leave with is the last one we looked at */
|
|
pss->page--;
|
|
return pages;
|
|
}
|
|
|
|
/**
|
|
* ram_find_and_save_block: finds a dirty page and sends it to f
|
|
*
|
|
* Called within an RCU critical section.
|
|
*
|
|
* Returns the number of pages written where zero means no dirty pages
|
|
*
|
|
* @rs: current RAM state
|
|
* @last_stage: if we are at the completion stage
|
|
*
|
|
* On systems where host-page-size > target-page-size it will send all the
|
|
* pages in a host page that are dirty.
|
|
*/
|
|
|
|
static int ram_find_and_save_block(RAMState *rs, bool last_stage)
|
|
{
|
|
PageSearchStatus pss;
|
|
int pages = 0;
|
|
bool again, found;
|
|
|
|
/* No dirty page as there is zero RAM */
|
|
if (!ram_bytes_total()) {
|
|
return pages;
|
|
}
|
|
|
|
pss.block = rs->last_seen_block;
|
|
pss.page = rs->last_page;
|
|
pss.complete_round = false;
|
|
|
|
if (!pss.block) {
|
|
pss.block = QLIST_FIRST_RCU(&ram_list.blocks);
|
|
}
|
|
|
|
do {
|
|
again = true;
|
|
found = get_queued_page(rs, &pss);
|
|
|
|
if (!found) {
|
|
/* priority queue empty, so just search for something dirty */
|
|
found = find_dirty_block(rs, &pss, &again);
|
|
}
|
|
|
|
if (found) {
|
|
pages = ram_save_host_page(rs, &pss, last_stage);
|
|
}
|
|
} while (!pages && again);
|
|
|
|
rs->last_seen_block = pss.block;
|
|
rs->last_page = pss.page;
|
|
|
|
return pages;
|
|
}
|
|
|
|
void acct_update_position(QEMUFile *f, size_t size, bool zero)
|
|
{
|
|
uint64_t pages = size / TARGET_PAGE_SIZE;
|
|
|
|
if (zero) {
|
|
ram_counters.duplicate += pages;
|
|
} else {
|
|
ram_counters.normal += pages;
|
|
ram_counters.transferred += size;
|
|
qemu_update_position(f, size);
|
|
}
|
|
}
|
|
|
|
uint64_t ram_bytes_total(void)
|
|
{
|
|
RAMBlock *block;
|
|
uint64_t total = 0;
|
|
|
|
rcu_read_lock();
|
|
RAMBLOCK_FOREACH_MIGRATABLE(block) {
|
|
total += block->used_length;
|
|
}
|
|
rcu_read_unlock();
|
|
return total;
|
|
}
|
|
|
|
static void xbzrle_load_setup(void)
|
|
{
|
|
XBZRLE.decoded_buf = g_malloc(TARGET_PAGE_SIZE);
|
|
}
|
|
|
|
static void xbzrle_load_cleanup(void)
|
|
{
|
|
g_free(XBZRLE.decoded_buf);
|
|
XBZRLE.decoded_buf = NULL;
|
|
}
|
|
|
|
static void ram_state_cleanup(RAMState **rsp)
|
|
{
|
|
if (*rsp) {
|
|
migration_page_queue_free(*rsp);
|
|
qemu_mutex_destroy(&(*rsp)->bitmap_mutex);
|
|
qemu_mutex_destroy(&(*rsp)->src_page_req_mutex);
|
|
g_free(*rsp);
|
|
*rsp = NULL;
|
|
}
|
|
}
|
|
|
|
static void xbzrle_cleanup(void)
|
|
{
|
|
XBZRLE_cache_lock();
|
|
if (XBZRLE.cache) {
|
|
cache_fini(XBZRLE.cache);
|
|
g_free(XBZRLE.encoded_buf);
|
|
g_free(XBZRLE.current_buf);
|
|
g_free(XBZRLE.zero_target_page);
|
|
XBZRLE.cache = NULL;
|
|
XBZRLE.encoded_buf = NULL;
|
|
XBZRLE.current_buf = NULL;
|
|
XBZRLE.zero_target_page = NULL;
|
|
}
|
|
XBZRLE_cache_unlock();
|
|
}
|
|
|
|
static void ram_save_cleanup(void *opaque)
|
|
{
|
|
RAMState **rsp = opaque;
|
|
RAMBlock *block;
|
|
|
|
/* caller have hold iothread lock or is in a bh, so there is
|
|
* no writing race against this migration_bitmap
|
|
*/
|
|
memory_global_dirty_log_stop();
|
|
|
|
RAMBLOCK_FOREACH_MIGRATABLE(block) {
|
|
g_free(block->bmap);
|
|
block->bmap = NULL;
|
|
g_free(block->unsentmap);
|
|
block->unsentmap = NULL;
|
|
}
|
|
|
|
xbzrle_cleanup();
|
|
compress_threads_save_cleanup();
|
|
ram_state_cleanup(rsp);
|
|
}
|
|
|
|
static void ram_state_reset(RAMState *rs)
|
|
{
|
|
rs->last_seen_block = NULL;
|
|
rs->last_sent_block = NULL;
|
|
rs->last_page = 0;
|
|
rs->last_version = ram_list.version;
|
|
rs->ram_bulk_stage = true;
|
|
}
|
|
|
|
#define MAX_WAIT 50 /* ms, half buffered_file limit */
|
|
|
|
/*
|
|
* 'expected' is the value you expect the bitmap mostly to be full
|
|
* of; it won't bother printing lines that are all this value.
|
|
* If 'todump' is null the migration bitmap is dumped.
|
|
*/
|
|
void ram_debug_dump_bitmap(unsigned long *todump, bool expected,
|
|
unsigned long pages)
|
|
{
|
|
int64_t cur;
|
|
int64_t linelen = 128;
|
|
char linebuf[129];
|
|
|
|
for (cur = 0; cur < pages; cur += linelen) {
|
|
int64_t curb;
|
|
bool found = false;
|
|
/*
|
|
* Last line; catch the case where the line length
|
|
* is longer than remaining ram
|
|
*/
|
|
if (cur + linelen > pages) {
|
|
linelen = pages - cur;
|
|
}
|
|
for (curb = 0; curb < linelen; curb++) {
|
|
bool thisbit = test_bit(cur + curb, todump);
|
|
linebuf[curb] = thisbit ? '1' : '.';
|
|
found = found || (thisbit != expected);
|
|
}
|
|
if (found) {
|
|
linebuf[curb] = '\0';
|
|
fprintf(stderr, "0x%08" PRIx64 " : %s\n", cur, linebuf);
|
|
}
|
|
}
|
|
}
|
|
|
|
/* **** functions for postcopy ***** */
|
|
|
|
void ram_postcopy_migrated_memory_release(MigrationState *ms)
|
|
{
|
|
struct RAMBlock *block;
|
|
|
|
RAMBLOCK_FOREACH_MIGRATABLE(block) {
|
|
unsigned long *bitmap = block->bmap;
|
|
unsigned long range = block->used_length >> TARGET_PAGE_BITS;
|
|
unsigned long run_start = find_next_zero_bit(bitmap, range, 0);
|
|
|
|
while (run_start < range) {
|
|
unsigned long run_end = find_next_bit(bitmap, range, run_start + 1);
|
|
ram_discard_range(block->idstr, run_start << TARGET_PAGE_BITS,
|
|
(run_end - run_start) << TARGET_PAGE_BITS);
|
|
run_start = find_next_zero_bit(bitmap, range, run_end + 1);
|
|
}
|
|
}
|
|
}
|
|
|
|
/**
|
|
* postcopy_send_discard_bm_ram: discard a RAMBlock
|
|
*
|
|
* Returns zero on success
|
|
*
|
|
* Callback from postcopy_each_ram_send_discard for each RAMBlock
|
|
* Note: At this point the 'unsentmap' is the processed bitmap combined
|
|
* with the dirtymap; so a '1' means it's either dirty or unsent.
|
|
*
|
|
* @ms: current migration state
|
|
* @pds: state for postcopy
|
|
* @start: RAMBlock starting page
|
|
* @length: RAMBlock size
|
|
*/
|
|
static int postcopy_send_discard_bm_ram(MigrationState *ms,
|
|
PostcopyDiscardState *pds,
|
|
RAMBlock *block)
|
|
{
|
|
unsigned long end = block->used_length >> TARGET_PAGE_BITS;
|
|
unsigned long current;
|
|
unsigned long *unsentmap = block->unsentmap;
|
|
|
|
for (current = 0; current < end; ) {
|
|
unsigned long one = find_next_bit(unsentmap, end, current);
|
|
|
|
if (one <= end) {
|
|
unsigned long zero = find_next_zero_bit(unsentmap, end, one + 1);
|
|
unsigned long discard_length;
|
|
|
|
if (zero >= end) {
|
|
discard_length = end - one;
|
|
} else {
|
|
discard_length = zero - one;
|
|
}
|
|
if (discard_length) {
|
|
postcopy_discard_send_range(ms, pds, one, discard_length);
|
|
}
|
|
current = one + discard_length;
|
|
} else {
|
|
current = one;
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* postcopy_each_ram_send_discard: discard all RAMBlocks
|
|
*
|
|
* Returns 0 for success or negative for error
|
|
*
|
|
* Utility for the outgoing postcopy code.
|
|
* Calls postcopy_send_discard_bm_ram for each RAMBlock
|
|
* passing it bitmap indexes and name.
|
|
* (qemu_ram_foreach_block ends up passing unscaled lengths
|
|
* which would mean postcopy code would have to deal with target page)
|
|
*
|
|
* @ms: current migration state
|
|
*/
|
|
static int postcopy_each_ram_send_discard(MigrationState *ms)
|
|
{
|
|
struct RAMBlock *block;
|
|
int ret;
|
|
|
|
RAMBLOCK_FOREACH_MIGRATABLE(block) {
|
|
PostcopyDiscardState *pds =
|
|
postcopy_discard_send_init(ms, block->idstr);
|
|
|
|
/*
|
|
* Postcopy sends chunks of bitmap over the wire, but it
|
|
* just needs indexes at this point, avoids it having
|
|
* target page specific code.
|
|
*/
|
|
ret = postcopy_send_discard_bm_ram(ms, pds, block);
|
|
postcopy_discard_send_finish(ms, pds);
|
|
if (ret) {
|
|
return ret;
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* postcopy_chunk_hostpages_pass: canocalize bitmap in hostpages
|
|
*
|
|
* Helper for postcopy_chunk_hostpages; it's called twice to
|
|
* canonicalize the two bitmaps, that are similar, but one is
|
|
* inverted.
|
|
*
|
|
* Postcopy requires that all target pages in a hostpage are dirty or
|
|
* clean, not a mix. This function canonicalizes the bitmaps.
|
|
*
|
|
* @ms: current migration state
|
|
* @unsent_pass: if true we need to canonicalize partially unsent host pages
|
|
* otherwise we need to canonicalize partially dirty host pages
|
|
* @block: block that contains the page we want to canonicalize
|
|
* @pds: state for postcopy
|
|
*/
|
|
static void postcopy_chunk_hostpages_pass(MigrationState *ms, bool unsent_pass,
|
|
RAMBlock *block,
|
|
PostcopyDiscardState *pds)
|
|
{
|
|
RAMState *rs = ram_state;
|
|
unsigned long *bitmap = block->bmap;
|
|
unsigned long *unsentmap = block->unsentmap;
|
|
unsigned int host_ratio = block->page_size / TARGET_PAGE_SIZE;
|
|
unsigned long pages = block->used_length >> TARGET_PAGE_BITS;
|
|
unsigned long run_start;
|
|
|
|
if (block->page_size == TARGET_PAGE_SIZE) {
|
|
/* Easy case - TPS==HPS for a non-huge page RAMBlock */
|
|
return;
|
|
}
|
|
|
|
if (unsent_pass) {
|
|
/* Find a sent page */
|
|
run_start = find_next_zero_bit(unsentmap, pages, 0);
|
|
} else {
|
|
/* Find a dirty page */
|
|
run_start = find_next_bit(bitmap, pages, 0);
|
|
}
|
|
|
|
while (run_start < pages) {
|
|
bool do_fixup = false;
|
|
unsigned long fixup_start_addr;
|
|
unsigned long host_offset;
|
|
|
|
/*
|
|
* If the start of this run of pages is in the middle of a host
|
|
* page, then we need to fixup this host page.
|
|
*/
|
|
host_offset = run_start % host_ratio;
|
|
if (host_offset) {
|
|
do_fixup = true;
|
|
run_start -= host_offset;
|
|
fixup_start_addr = run_start;
|
|
/* For the next pass */
|
|
run_start = run_start + host_ratio;
|
|
} else {
|
|
/* Find the end of this run */
|
|
unsigned long run_end;
|
|
if (unsent_pass) {
|
|
run_end = find_next_bit(unsentmap, pages, run_start + 1);
|
|
} else {
|
|
run_end = find_next_zero_bit(bitmap, pages, run_start + 1);
|
|
}
|
|
/*
|
|
* If the end isn't at the start of a host page, then the
|
|
* run doesn't finish at the end of a host page
|
|
* and we need to discard.
|
|
*/
|
|
host_offset = run_end % host_ratio;
|
|
if (host_offset) {
|
|
do_fixup = true;
|
|
fixup_start_addr = run_end - host_offset;
|
|
/*
|
|
* This host page has gone, the next loop iteration starts
|
|
* from after the fixup
|
|
*/
|
|
run_start = fixup_start_addr + host_ratio;
|
|
} else {
|
|
/*
|
|
* No discards on this iteration, next loop starts from
|
|
* next sent/dirty page
|
|
*/
|
|
run_start = run_end + 1;
|
|
}
|
|
}
|
|
|
|
if (do_fixup) {
|
|
unsigned long page;
|
|
|
|
/* Tell the destination to discard this page */
|
|
if (unsent_pass || !test_bit(fixup_start_addr, unsentmap)) {
|
|
/* For the unsent_pass we:
|
|
* discard partially sent pages
|
|
* For the !unsent_pass (dirty) we:
|
|
* discard partially dirty pages that were sent
|
|
* (any partially sent pages were already discarded
|
|
* by the previous unsent_pass)
|
|
*/
|
|
postcopy_discard_send_range(ms, pds, fixup_start_addr,
|
|
host_ratio);
|
|
}
|
|
|
|
/* Clean up the bitmap */
|
|
for (page = fixup_start_addr;
|
|
page < fixup_start_addr + host_ratio; page++) {
|
|
/* All pages in this host page are now not sent */
|
|
set_bit(page, unsentmap);
|
|
|
|
/*
|
|
* Remark them as dirty, updating the count for any pages
|
|
* that weren't previously dirty.
|
|
*/
|
|
rs->migration_dirty_pages += !test_and_set_bit(page, bitmap);
|
|
}
|
|
}
|
|
|
|
if (unsent_pass) {
|
|
/* Find the next sent page for the next iteration */
|
|
run_start = find_next_zero_bit(unsentmap, pages, run_start);
|
|
} else {
|
|
/* Find the next dirty page for the next iteration */
|
|
run_start = find_next_bit(bitmap, pages, run_start);
|
|
}
|
|
}
|
|
}
|
|
|
|
/**
|
|
* postcopy_chuck_hostpages: discrad any partially sent host page
|
|
*
|
|
* Utility for the outgoing postcopy code.
|
|
*
|
|
* Discard any partially sent host-page size chunks, mark any partially
|
|
* dirty host-page size chunks as all dirty. In this case the host-page
|
|
* is the host-page for the particular RAMBlock, i.e. it might be a huge page
|
|
*
|
|
* Returns zero on success
|
|
*
|
|
* @ms: current migration state
|
|
* @block: block we want to work with
|
|
*/
|
|
static int postcopy_chunk_hostpages(MigrationState *ms, RAMBlock *block)
|
|
{
|
|
PostcopyDiscardState *pds =
|
|
postcopy_discard_send_init(ms, block->idstr);
|
|
|
|
/* First pass: Discard all partially sent host pages */
|
|
postcopy_chunk_hostpages_pass(ms, true, block, pds);
|
|
/*
|
|
* Second pass: Ensure that all partially dirty host pages are made
|
|
* fully dirty.
|
|
*/
|
|
postcopy_chunk_hostpages_pass(ms, false, block, pds);
|
|
|
|
postcopy_discard_send_finish(ms, pds);
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* ram_postcopy_send_discard_bitmap: transmit the discard bitmap
|
|
*
|
|
* Returns zero on success
|
|
*
|
|
* Transmit the set of pages to be discarded after precopy to the target
|
|
* these are pages that:
|
|
* a) Have been previously transmitted but are now dirty again
|
|
* b) Pages that have never been transmitted, this ensures that
|
|
* any pages on the destination that have been mapped by background
|
|
* tasks get discarded (transparent huge pages is the specific concern)
|
|
* Hopefully this is pretty sparse
|
|
*
|
|
* @ms: current migration state
|
|
*/
|
|
int ram_postcopy_send_discard_bitmap(MigrationState *ms)
|
|
{
|
|
RAMState *rs = ram_state;
|
|
RAMBlock *block;
|
|
int ret;
|
|
|
|
rcu_read_lock();
|
|
|
|
/* This should be our last sync, the src is now paused */
|
|
migration_bitmap_sync(rs);
|
|
|
|
/* Easiest way to make sure we don't resume in the middle of a host-page */
|
|
rs->last_seen_block = NULL;
|
|
rs->last_sent_block = NULL;
|
|
rs->last_page = 0;
|
|
|
|
RAMBLOCK_FOREACH_MIGRATABLE(block) {
|
|
unsigned long pages = block->used_length >> TARGET_PAGE_BITS;
|
|
unsigned long *bitmap = block->bmap;
|
|
unsigned long *unsentmap = block->unsentmap;
|
|
|
|
if (!unsentmap) {
|
|
/* We don't have a safe way to resize the sentmap, so
|
|
* if the bitmap was resized it will be NULL at this
|
|
* point.
|
|
*/
|
|
error_report("migration ram resized during precopy phase");
|
|
rcu_read_unlock();
|
|
return -EINVAL;
|
|
}
|
|
/* Deal with TPS != HPS and huge pages */
|
|
ret = postcopy_chunk_hostpages(ms, block);
|
|
if (ret) {
|
|
rcu_read_unlock();
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Update the unsentmap to be unsentmap = unsentmap | dirty
|
|
*/
|
|
bitmap_or(unsentmap, unsentmap, bitmap, pages);
|
|
#ifdef DEBUG_POSTCOPY
|
|
ram_debug_dump_bitmap(unsentmap, true, pages);
|
|
#endif
|
|
}
|
|
trace_ram_postcopy_send_discard_bitmap();
|
|
|
|
ret = postcopy_each_ram_send_discard(ms);
|
|
rcu_read_unlock();
|
|
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* ram_discard_range: discard dirtied pages at the beginning of postcopy
|
|
*
|
|
* Returns zero on success
|
|
*
|
|
* @rbname: name of the RAMBlock of the request. NULL means the
|
|
* same that last one.
|
|
* @start: RAMBlock starting page
|
|
* @length: RAMBlock size
|
|
*/
|
|
int ram_discard_range(const char *rbname, uint64_t start, size_t length)
|
|
{
|
|
int ret = -1;
|
|
|
|
trace_ram_discard_range(rbname, start, length);
|
|
|
|
rcu_read_lock();
|
|
RAMBlock *rb = qemu_ram_block_by_name(rbname);
|
|
|
|
if (!rb) {
|
|
error_report("ram_discard_range: Failed to find block '%s'", rbname);
|
|
goto err;
|
|
}
|
|
|
|
bitmap_clear(rb->receivedmap, start >> qemu_target_page_bits(),
|
|
length >> qemu_target_page_bits());
|
|
ret = ram_block_discard_range(rb, start, length);
|
|
|
|
err:
|
|
rcu_read_unlock();
|
|
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* For every allocation, we will try not to crash the VM if the
|
|
* allocation failed.
|
|
*/
|
|
static int xbzrle_init(void)
|
|
{
|
|
Error *local_err = NULL;
|
|
|
|
if (!migrate_use_xbzrle()) {
|
|
return 0;
|
|
}
|
|
|
|
XBZRLE_cache_lock();
|
|
|
|
XBZRLE.zero_target_page = g_try_malloc0(TARGET_PAGE_SIZE);
|
|
if (!XBZRLE.zero_target_page) {
|
|
error_report("%s: Error allocating zero page", __func__);
|
|
goto err_out;
|
|
}
|
|
|
|
XBZRLE.cache = cache_init(migrate_xbzrle_cache_size(),
|
|
TARGET_PAGE_SIZE, &local_err);
|
|
if (!XBZRLE.cache) {
|
|
error_report_err(local_err);
|
|
goto free_zero_page;
|
|
}
|
|
|
|
XBZRLE.encoded_buf = g_try_malloc0(TARGET_PAGE_SIZE);
|
|
if (!XBZRLE.encoded_buf) {
|
|
error_report("%s: Error allocating encoded_buf", __func__);
|
|
goto free_cache;
|
|
}
|
|
|
|
XBZRLE.current_buf = g_try_malloc(TARGET_PAGE_SIZE);
|
|
if (!XBZRLE.current_buf) {
|
|
error_report("%s: Error allocating current_buf", __func__);
|
|
goto free_encoded_buf;
|
|
}
|
|
|
|
/* We are all good */
|
|
XBZRLE_cache_unlock();
|
|
return 0;
|
|
|
|
free_encoded_buf:
|
|
g_free(XBZRLE.encoded_buf);
|
|
XBZRLE.encoded_buf = NULL;
|
|
free_cache:
|
|
cache_fini(XBZRLE.cache);
|
|
XBZRLE.cache = NULL;
|
|
free_zero_page:
|
|
g_free(XBZRLE.zero_target_page);
|
|
XBZRLE.zero_target_page = NULL;
|
|
err_out:
|
|
XBZRLE_cache_unlock();
|
|
return -ENOMEM;
|
|
}
|
|
|
|
static int ram_state_init(RAMState **rsp)
|
|
{
|
|
*rsp = g_try_new0(RAMState, 1);
|
|
|
|
if (!*rsp) {
|
|
error_report("%s: Init ramstate fail", __func__);
|
|
return -1;
|
|
}
|
|
|
|
qemu_mutex_init(&(*rsp)->bitmap_mutex);
|
|
qemu_mutex_init(&(*rsp)->src_page_req_mutex);
|
|
QSIMPLEQ_INIT(&(*rsp)->src_page_requests);
|
|
|
|
/*
|
|
* Count the total number of pages used by ram blocks not including any
|
|
* gaps due to alignment or unplugs.
|
|
*/
|
|
(*rsp)->migration_dirty_pages = ram_bytes_total() >> TARGET_PAGE_BITS;
|
|
|
|
ram_state_reset(*rsp);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void ram_list_init_bitmaps(void)
|
|
{
|
|
RAMBlock *block;
|
|
unsigned long pages;
|
|
|
|
/* Skip setting bitmap if there is no RAM */
|
|
if (ram_bytes_total()) {
|
|
RAMBLOCK_FOREACH_MIGRATABLE(block) {
|
|
pages = block->max_length >> TARGET_PAGE_BITS;
|
|
block->bmap = bitmap_new(pages);
|
|
bitmap_set(block->bmap, 0, pages);
|
|
if (migrate_postcopy_ram()) {
|
|
block->unsentmap = bitmap_new(pages);
|
|
bitmap_set(block->unsentmap, 0, pages);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
static void ram_init_bitmaps(RAMState *rs)
|
|
{
|
|
/* For memory_global_dirty_log_start below. */
|
|
qemu_mutex_lock_iothread();
|
|
qemu_mutex_lock_ramlist();
|
|
rcu_read_lock();
|
|
|
|
ram_list_init_bitmaps();
|
|
memory_global_dirty_log_start();
|
|
migration_bitmap_sync(rs);
|
|
|
|
rcu_read_unlock();
|
|
qemu_mutex_unlock_ramlist();
|
|
qemu_mutex_unlock_iothread();
|
|
}
|
|
|
|
static int ram_init_all(RAMState **rsp)
|
|
{
|
|
if (ram_state_init(rsp)) {
|
|
return -1;
|
|
}
|
|
|
|
if (xbzrle_init()) {
|
|
ram_state_cleanup(rsp);
|
|
return -1;
|
|
}
|
|
|
|
ram_init_bitmaps(*rsp);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void ram_state_resume_prepare(RAMState *rs, QEMUFile *out)
|
|
{
|
|
RAMBlock *block;
|
|
uint64_t pages = 0;
|
|
|
|
/*
|
|
* Postcopy is not using xbzrle/compression, so no need for that.
|
|
* Also, since source are already halted, we don't need to care
|
|
* about dirty page logging as well.
|
|
*/
|
|
|
|
RAMBLOCK_FOREACH(block) {
|
|
pages += bitmap_count_one(block->bmap,
|
|
block->used_length >> TARGET_PAGE_BITS);
|
|
}
|
|
|
|
/* This may not be aligned with current bitmaps. Recalculate. */
|
|
rs->migration_dirty_pages = pages;
|
|
|
|
rs->last_seen_block = NULL;
|
|
rs->last_sent_block = NULL;
|
|
rs->last_page = 0;
|
|
rs->last_version = ram_list.version;
|
|
/*
|
|
* Disable the bulk stage, otherwise we'll resend the whole RAM no
|
|
* matter what we have sent.
|
|
*/
|
|
rs->ram_bulk_stage = false;
|
|
|
|
/* Update RAMState cache of output QEMUFile */
|
|
rs->f = out;
|
|
|
|
trace_ram_state_resume_prepare(pages);
|
|
}
|
|
|
|
/*
|
|
* Each of ram_save_setup, ram_save_iterate and ram_save_complete has
|
|
* long-running RCU critical section. When rcu-reclaims in the code
|
|
* start to become numerous it will be necessary to reduce the
|
|
* granularity of these critical sections.
|
|
*/
|
|
|
|
/**
|
|
* ram_save_setup: Setup RAM for migration
|
|
*
|
|
* Returns zero to indicate success and negative for error
|
|
*
|
|
* @f: QEMUFile where to send the data
|
|
* @opaque: RAMState pointer
|
|
*/
|
|
static int ram_save_setup(QEMUFile *f, void *opaque)
|
|
{
|
|
RAMState **rsp = opaque;
|
|
RAMBlock *block;
|
|
|
|
if (compress_threads_save_setup()) {
|
|
return -1;
|
|
}
|
|
|
|
/* migration has already setup the bitmap, reuse it. */
|
|
if (!migration_in_colo_state()) {
|
|
if (ram_init_all(rsp) != 0) {
|
|
compress_threads_save_cleanup();
|
|
return -1;
|
|
}
|
|
}
|
|
(*rsp)->f = f;
|
|
|
|
rcu_read_lock();
|
|
|
|
qemu_put_be64(f, ram_bytes_total() | RAM_SAVE_FLAG_MEM_SIZE);
|
|
|
|
RAMBLOCK_FOREACH_MIGRATABLE(block) {
|
|
qemu_put_byte(f, strlen(block->idstr));
|
|
qemu_put_buffer(f, (uint8_t *)block->idstr, strlen(block->idstr));
|
|
qemu_put_be64(f, block->used_length);
|
|
if (migrate_postcopy_ram() && block->page_size != qemu_host_page_size) {
|
|
qemu_put_be64(f, block->page_size);
|
|
}
|
|
}
|
|
|
|
rcu_read_unlock();
|
|
|
|
ram_control_before_iterate(f, RAM_CONTROL_SETUP);
|
|
ram_control_after_iterate(f, RAM_CONTROL_SETUP);
|
|
|
|
qemu_put_be64(f, RAM_SAVE_FLAG_EOS);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* ram_save_iterate: iterative stage for migration
|
|
*
|
|
* Returns zero to indicate success and negative for error
|
|
*
|
|
* @f: QEMUFile where to send the data
|
|
* @opaque: RAMState pointer
|
|
*/
|
|
static int ram_save_iterate(QEMUFile *f, void *opaque)
|
|
{
|
|
RAMState **temp = opaque;
|
|
RAMState *rs = *temp;
|
|
int ret;
|
|
int i;
|
|
int64_t t0;
|
|
int done = 0;
|
|
|
|
if (blk_mig_bulk_active()) {
|
|
/* Avoid transferring ram during bulk phase of block migration as
|
|
* the bulk phase will usually take a long time and transferring
|
|
* ram updates during that time is pointless. */
|
|
goto out;
|
|
}
|
|
|
|
rcu_read_lock();
|
|
if (ram_list.version != rs->last_version) {
|
|
ram_state_reset(rs);
|
|
}
|
|
|
|
/* Read version before ram_list.blocks */
|
|
smp_rmb();
|
|
|
|
ram_control_before_iterate(f, RAM_CONTROL_ROUND);
|
|
|
|
t0 = qemu_clock_get_ns(QEMU_CLOCK_REALTIME);
|
|
i = 0;
|
|
while ((ret = qemu_file_rate_limit(f)) == 0) {
|
|
int pages;
|
|
|
|
pages = ram_find_and_save_block(rs, false);
|
|
/* no more pages to sent */
|
|
if (pages == 0) {
|
|
done = 1;
|
|
break;
|
|
}
|
|
rs->iterations++;
|
|
|
|
/* we want to check in the 1st loop, just in case it was the 1st time
|
|
and we had to sync the dirty bitmap.
|
|
qemu_get_clock_ns() is a bit expensive, so we only check each some
|
|
iterations
|
|
*/
|
|
if ((i & 63) == 0) {
|
|
uint64_t t1 = (qemu_clock_get_ns(QEMU_CLOCK_REALTIME) - t0) / 1000000;
|
|
if (t1 > MAX_WAIT) {
|
|
trace_ram_save_iterate_big_wait(t1, i);
|
|
break;
|
|
}
|
|
}
|
|
i++;
|
|
}
|
|
flush_compressed_data(rs);
|
|
rcu_read_unlock();
|
|
|
|
/*
|
|
* Must occur before EOS (or any QEMUFile operation)
|
|
* because of RDMA protocol.
|
|
*/
|
|
ram_control_after_iterate(f, RAM_CONTROL_ROUND);
|
|
|
|
out:
|
|
qemu_put_be64(f, RAM_SAVE_FLAG_EOS);
|
|
ram_counters.transferred += 8;
|
|
|
|
ret = qemu_file_get_error(f);
|
|
if (ret < 0) {
|
|
return ret;
|
|
}
|
|
|
|
return done;
|
|
}
|
|
|
|
/**
|
|
* ram_save_complete: function called to send the remaining amount of ram
|
|
*
|
|
* Returns zero to indicate success
|
|
*
|
|
* Called with iothread lock
|
|
*
|
|
* @f: QEMUFile where to send the data
|
|
* @opaque: RAMState pointer
|
|
*/
|
|
static int ram_save_complete(QEMUFile *f, void *opaque)
|
|
{
|
|
RAMState **temp = opaque;
|
|
RAMState *rs = *temp;
|
|
|
|
rcu_read_lock();
|
|
|
|
if (!migration_in_postcopy()) {
|
|
migration_bitmap_sync(rs);
|
|
}
|
|
|
|
ram_control_before_iterate(f, RAM_CONTROL_FINISH);
|
|
|
|
/* try transferring iterative blocks of memory */
|
|
|
|
/* flush all remaining blocks regardless of rate limiting */
|
|
while (true) {
|
|
int pages;
|
|
|
|
pages = ram_find_and_save_block(rs, !migration_in_colo_state());
|
|
/* no more blocks to sent */
|
|
if (pages == 0) {
|
|
break;
|
|
}
|
|
}
|
|
|
|
flush_compressed_data(rs);
|
|
ram_control_after_iterate(f, RAM_CONTROL_FINISH);
|
|
|
|
rcu_read_unlock();
|
|
|
|
qemu_put_be64(f, RAM_SAVE_FLAG_EOS);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void ram_save_pending(QEMUFile *f, void *opaque, uint64_t max_size,
|
|
uint64_t *res_precopy_only,
|
|
uint64_t *res_compatible,
|
|
uint64_t *res_postcopy_only)
|
|
{
|
|
RAMState **temp = opaque;
|
|
RAMState *rs = *temp;
|
|
uint64_t remaining_size;
|
|
|
|
remaining_size = rs->migration_dirty_pages * TARGET_PAGE_SIZE;
|
|
|
|
if (!migration_in_postcopy() &&
|
|
remaining_size < max_size) {
|
|
qemu_mutex_lock_iothread();
|
|
rcu_read_lock();
|
|
migration_bitmap_sync(rs);
|
|
rcu_read_unlock();
|
|
qemu_mutex_unlock_iothread();
|
|
remaining_size = rs->migration_dirty_pages * TARGET_PAGE_SIZE;
|
|
}
|
|
|
|
if (migrate_postcopy_ram()) {
|
|
/* We can do postcopy, and all the data is postcopiable */
|
|
*res_compatible += remaining_size;
|
|
} else {
|
|
*res_precopy_only += remaining_size;
|
|
}
|
|
}
|
|
|
|
static int load_xbzrle(QEMUFile *f, ram_addr_t addr, void *host)
|
|
{
|
|
unsigned int xh_len;
|
|
int xh_flags;
|
|
uint8_t *loaded_data;
|
|
|
|
/* extract RLE header */
|
|
xh_flags = qemu_get_byte(f);
|
|
xh_len = qemu_get_be16(f);
|
|
|
|
if (xh_flags != ENCODING_FLAG_XBZRLE) {
|
|
error_report("Failed to load XBZRLE page - wrong compression!");
|
|
return -1;
|
|
}
|
|
|
|
if (xh_len > TARGET_PAGE_SIZE) {
|
|
error_report("Failed to load XBZRLE page - len overflow!");
|
|
return -1;
|
|
}
|
|
loaded_data = XBZRLE.decoded_buf;
|
|
/* load data and decode */
|
|
/* it can change loaded_data to point to an internal buffer */
|
|
qemu_get_buffer_in_place(f, &loaded_data, xh_len);
|
|
|
|
/* decode RLE */
|
|
if (xbzrle_decode_buffer(loaded_data, xh_len, host,
|
|
TARGET_PAGE_SIZE) == -1) {
|
|
error_report("Failed to load XBZRLE page - decode error!");
|
|
return -1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* ram_block_from_stream: read a RAMBlock id from the migration stream
|
|
*
|
|
* Must be called from within a rcu critical section.
|
|
*
|
|
* Returns a pointer from within the RCU-protected ram_list.
|
|
*
|
|
* @f: QEMUFile where to read the data from
|
|
* @flags: Page flags (mostly to see if it's a continuation of previous block)
|
|
*/
|
|
static inline RAMBlock *ram_block_from_stream(QEMUFile *f, int flags)
|
|
{
|
|
static RAMBlock *block = NULL;
|
|
char id[256];
|
|
uint8_t len;
|
|
|
|
if (flags & RAM_SAVE_FLAG_CONTINUE) {
|
|
if (!block) {
|
|
error_report("Ack, bad migration stream!");
|
|
return NULL;
|
|
}
|
|
return block;
|
|
}
|
|
|
|
len = qemu_get_byte(f);
|
|
qemu_get_buffer(f, (uint8_t *)id, len);
|
|
id[len] = 0;
|
|
|
|
block = qemu_ram_block_by_name(id);
|
|
if (!block) {
|
|
error_report("Can't find block %s", id);
|
|
return NULL;
|
|
}
|
|
|
|
if (!qemu_ram_is_migratable(block)) {
|
|
error_report("block %s should not be migrated !", id);
|
|
return NULL;
|
|
}
|
|
|
|
return block;
|
|
}
|
|
|
|
static inline void *host_from_ram_block_offset(RAMBlock *block,
|
|
ram_addr_t offset)
|
|
{
|
|
if (!offset_in_ramblock(block, offset)) {
|
|
return NULL;
|
|
}
|
|
|
|
return block->host + offset;
|
|
}
|
|
|
|
/**
|
|
* ram_handle_compressed: handle the zero page case
|
|
*
|
|
* If a page (or a whole RDMA chunk) has been
|
|
* determined to be zero, then zap it.
|
|
*
|
|
* @host: host address for the zero page
|
|
* @ch: what the page is filled from. We only support zero
|
|
* @size: size of the zero page
|
|
*/
|
|
void ram_handle_compressed(void *host, uint8_t ch, uint64_t size)
|
|
{
|
|
if (ch != 0 || !is_zero_range(host, size)) {
|
|
memset(host, ch, size);
|
|
}
|
|
}
|
|
|
|
/* return the size after decompression, or negative value on error */
|
|
static int
|
|
qemu_uncompress_data(z_stream *stream, uint8_t *dest, size_t dest_len,
|
|
const uint8_t *source, size_t source_len)
|
|
{
|
|
int err;
|
|
|
|
err = inflateReset(stream);
|
|
if (err != Z_OK) {
|
|
return -1;
|
|
}
|
|
|
|
stream->avail_in = source_len;
|
|
stream->next_in = (uint8_t *)source;
|
|
stream->avail_out = dest_len;
|
|
stream->next_out = dest;
|
|
|
|
err = inflate(stream, Z_NO_FLUSH);
|
|
if (err != Z_STREAM_END) {
|
|
return -1;
|
|
}
|
|
|
|
return stream->total_out;
|
|
}
|
|
|
|
static void *do_data_decompress(void *opaque)
|
|
{
|
|
DecompressParam *param = opaque;
|
|
unsigned long pagesize;
|
|
uint8_t *des;
|
|
int len, ret;
|
|
|
|
qemu_mutex_lock(¶m->mutex);
|
|
while (!param->quit) {
|
|
if (param->des) {
|
|
des = param->des;
|
|
len = param->len;
|
|
param->des = 0;
|
|
qemu_mutex_unlock(¶m->mutex);
|
|
|
|
pagesize = TARGET_PAGE_SIZE;
|
|
|
|
ret = qemu_uncompress_data(¶m->stream, des, pagesize,
|
|
param->compbuf, len);
|
|
if (ret < 0 && migrate_get_current()->decompress_error_check) {
|
|
error_report("decompress data failed");
|
|
qemu_file_set_error(decomp_file, ret);
|
|
}
|
|
|
|
qemu_mutex_lock(&decomp_done_lock);
|
|
param->done = true;
|
|
qemu_cond_signal(&decomp_done_cond);
|
|
qemu_mutex_unlock(&decomp_done_lock);
|
|
|
|
qemu_mutex_lock(¶m->mutex);
|
|
} else {
|
|
qemu_cond_wait(¶m->cond, ¶m->mutex);
|
|
}
|
|
}
|
|
qemu_mutex_unlock(¶m->mutex);
|
|
|
|
return NULL;
|
|
}
|
|
|
|
static int wait_for_decompress_done(void)
|
|
{
|
|
int idx, thread_count;
|
|
|
|
if (!migrate_use_compression()) {
|
|
return 0;
|
|
}
|
|
|
|
thread_count = migrate_decompress_threads();
|
|
qemu_mutex_lock(&decomp_done_lock);
|
|
for (idx = 0; idx < thread_count; idx++) {
|
|
while (!decomp_param[idx].done) {
|
|
qemu_cond_wait(&decomp_done_cond, &decomp_done_lock);
|
|
}
|
|
}
|
|
qemu_mutex_unlock(&decomp_done_lock);
|
|
return qemu_file_get_error(decomp_file);
|
|
}
|
|
|
|
static void compress_threads_load_cleanup(void)
|
|
{
|
|
int i, thread_count;
|
|
|
|
if (!migrate_use_compression()) {
|
|
return;
|
|
}
|
|
thread_count = migrate_decompress_threads();
|
|
for (i = 0; i < thread_count; i++) {
|
|
/*
|
|
* we use it as a indicator which shows if the thread is
|
|
* properly init'd or not
|
|
*/
|
|
if (!decomp_param[i].compbuf) {
|
|
break;
|
|
}
|
|
|
|
qemu_mutex_lock(&decomp_param[i].mutex);
|
|
decomp_param[i].quit = true;
|
|
qemu_cond_signal(&decomp_param[i].cond);
|
|
qemu_mutex_unlock(&decomp_param[i].mutex);
|
|
}
|
|
for (i = 0; i < thread_count; i++) {
|
|
if (!decomp_param[i].compbuf) {
|
|
break;
|
|
}
|
|
|
|
qemu_thread_join(decompress_threads + i);
|
|
qemu_mutex_destroy(&decomp_param[i].mutex);
|
|
qemu_cond_destroy(&decomp_param[i].cond);
|
|
inflateEnd(&decomp_param[i].stream);
|
|
g_free(decomp_param[i].compbuf);
|
|
decomp_param[i].compbuf = NULL;
|
|
}
|
|
g_free(decompress_threads);
|
|
g_free(decomp_param);
|
|
decompress_threads = NULL;
|
|
decomp_param = NULL;
|
|
decomp_file = NULL;
|
|
}
|
|
|
|
static int compress_threads_load_setup(QEMUFile *f)
|
|
{
|
|
int i, thread_count;
|
|
|
|
if (!migrate_use_compression()) {
|
|
return 0;
|
|
}
|
|
|
|
thread_count = migrate_decompress_threads();
|
|
decompress_threads = g_new0(QemuThread, thread_count);
|
|
decomp_param = g_new0(DecompressParam, thread_count);
|
|
qemu_mutex_init(&decomp_done_lock);
|
|
qemu_cond_init(&decomp_done_cond);
|
|
decomp_file = f;
|
|
for (i = 0; i < thread_count; i++) {
|
|
if (inflateInit(&decomp_param[i].stream) != Z_OK) {
|
|
goto exit;
|
|
}
|
|
|
|
decomp_param[i].compbuf = g_malloc0(compressBound(TARGET_PAGE_SIZE));
|
|
qemu_mutex_init(&decomp_param[i].mutex);
|
|
qemu_cond_init(&decomp_param[i].cond);
|
|
decomp_param[i].done = true;
|
|
decomp_param[i].quit = false;
|
|
qemu_thread_create(decompress_threads + i, "decompress",
|
|
do_data_decompress, decomp_param + i,
|
|
QEMU_THREAD_JOINABLE);
|
|
}
|
|
return 0;
|
|
exit:
|
|
compress_threads_load_cleanup();
|
|
return -1;
|
|
}
|
|
|
|
static void decompress_data_with_multi_threads(QEMUFile *f,
|
|
void *host, int len)
|
|
{
|
|
int idx, thread_count;
|
|
|
|
thread_count = migrate_decompress_threads();
|
|
qemu_mutex_lock(&decomp_done_lock);
|
|
while (true) {
|
|
for (idx = 0; idx < thread_count; idx++) {
|
|
if (decomp_param[idx].done) {
|
|
decomp_param[idx].done = false;
|
|
qemu_mutex_lock(&decomp_param[idx].mutex);
|
|
qemu_get_buffer(f, decomp_param[idx].compbuf, len);
|
|
decomp_param[idx].des = host;
|
|
decomp_param[idx].len = len;
|
|
qemu_cond_signal(&decomp_param[idx].cond);
|
|
qemu_mutex_unlock(&decomp_param[idx].mutex);
|
|
break;
|
|
}
|
|
}
|
|
if (idx < thread_count) {
|
|
break;
|
|
} else {
|
|
qemu_cond_wait(&decomp_done_cond, &decomp_done_lock);
|
|
}
|
|
}
|
|
qemu_mutex_unlock(&decomp_done_lock);
|
|
}
|
|
|
|
/**
|
|
* ram_load_setup: Setup RAM for migration incoming side
|
|
*
|
|
* Returns zero to indicate success and negative for error
|
|
*
|
|
* @f: QEMUFile where to receive the data
|
|
* @opaque: RAMState pointer
|
|
*/
|
|
static int ram_load_setup(QEMUFile *f, void *opaque)
|
|
{
|
|
if (compress_threads_load_setup(f)) {
|
|
return -1;
|
|
}
|
|
|
|
xbzrle_load_setup();
|
|
ramblock_recv_map_init();
|
|
return 0;
|
|
}
|
|
|
|
static int ram_load_cleanup(void *opaque)
|
|
{
|
|
RAMBlock *rb;
|
|
xbzrle_load_cleanup();
|
|
compress_threads_load_cleanup();
|
|
|
|
RAMBLOCK_FOREACH_MIGRATABLE(rb) {
|
|
g_free(rb->receivedmap);
|
|
rb->receivedmap = NULL;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* ram_postcopy_incoming_init: allocate postcopy data structures
|
|
*
|
|
* Returns 0 for success and negative if there was one error
|
|
*
|
|
* @mis: current migration incoming state
|
|
*
|
|
* Allocate data structures etc needed by incoming migration with
|
|
* postcopy-ram. postcopy-ram's similarly names
|
|
* postcopy_ram_incoming_init does the work.
|
|
*/
|
|
int ram_postcopy_incoming_init(MigrationIncomingState *mis)
|
|
{
|
|
unsigned long ram_pages = last_ram_page();
|
|
|
|
return postcopy_ram_incoming_init(mis, ram_pages);
|
|
}
|
|
|
|
/**
|
|
* ram_load_postcopy: load a page in postcopy case
|
|
*
|
|
* Returns 0 for success or -errno in case of error
|
|
*
|
|
* Called in postcopy mode by ram_load().
|
|
* rcu_read_lock is taken prior to this being called.
|
|
*
|
|
* @f: QEMUFile where to send the data
|
|
*/
|
|
static int ram_load_postcopy(QEMUFile *f)
|
|
{
|
|
int flags = 0, ret = 0;
|
|
bool place_needed = false;
|
|
bool matching_page_sizes = false;
|
|
MigrationIncomingState *mis = migration_incoming_get_current();
|
|
/* Temporary page that is later 'placed' */
|
|
void *postcopy_host_page = postcopy_get_tmp_page(mis);
|
|
void *last_host = NULL;
|
|
bool all_zero = false;
|
|
|
|
while (!ret && !(flags & RAM_SAVE_FLAG_EOS)) {
|
|
ram_addr_t addr;
|
|
void *host = NULL;
|
|
void *page_buffer = NULL;
|
|
void *place_source = NULL;
|
|
RAMBlock *block = NULL;
|
|
uint8_t ch;
|
|
|
|
addr = qemu_get_be64(f);
|
|
|
|
/*
|
|
* If qemu file error, we should stop here, and then "addr"
|
|
* may be invalid
|
|
*/
|
|
ret = qemu_file_get_error(f);
|
|
if (ret) {
|
|
break;
|
|
}
|
|
|
|
flags = addr & ~TARGET_PAGE_MASK;
|
|
addr &= TARGET_PAGE_MASK;
|
|
|
|
trace_ram_load_postcopy_loop((uint64_t)addr, flags);
|
|
place_needed = false;
|
|
if (flags & (RAM_SAVE_FLAG_ZERO | RAM_SAVE_FLAG_PAGE)) {
|
|
block = ram_block_from_stream(f, flags);
|
|
|
|
host = host_from_ram_block_offset(block, addr);
|
|
if (!host) {
|
|
error_report("Illegal RAM offset " RAM_ADDR_FMT, addr);
|
|
ret = -EINVAL;
|
|
break;
|
|
}
|
|
matching_page_sizes = block->page_size == TARGET_PAGE_SIZE;
|
|
/*
|
|
* Postcopy requires that we place whole host pages atomically;
|
|
* these may be huge pages for RAMBlocks that are backed by
|
|
* hugetlbfs.
|
|
* To make it atomic, the data is read into a temporary page
|
|
* that's moved into place later.
|
|
* The migration protocol uses, possibly smaller, target-pages
|
|
* however the source ensures it always sends all the components
|
|
* of a host page in order.
|
|
*/
|
|
page_buffer = postcopy_host_page +
|
|
((uintptr_t)host & (block->page_size - 1));
|
|
/* If all TP are zero then we can optimise the place */
|
|
if (!((uintptr_t)host & (block->page_size - 1))) {
|
|
all_zero = true;
|
|
} else {
|
|
/* not the 1st TP within the HP */
|
|
if (host != (last_host + TARGET_PAGE_SIZE)) {
|
|
error_report("Non-sequential target page %p/%p",
|
|
host, last_host);
|
|
ret = -EINVAL;
|
|
break;
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
* If it's the last part of a host page then we place the host
|
|
* page
|
|
*/
|
|
place_needed = (((uintptr_t)host + TARGET_PAGE_SIZE) &
|
|
(block->page_size - 1)) == 0;
|
|
place_source = postcopy_host_page;
|
|
}
|
|
last_host = host;
|
|
|
|
switch (flags & ~RAM_SAVE_FLAG_CONTINUE) {
|
|
case RAM_SAVE_FLAG_ZERO:
|
|
ch = qemu_get_byte(f);
|
|
memset(page_buffer, ch, TARGET_PAGE_SIZE);
|
|
if (ch) {
|
|
all_zero = false;
|
|
}
|
|
break;
|
|
|
|
case RAM_SAVE_FLAG_PAGE:
|
|
all_zero = false;
|
|
if (!place_needed || !matching_page_sizes) {
|
|
qemu_get_buffer(f, page_buffer, TARGET_PAGE_SIZE);
|
|
} else {
|
|
/* Avoids the qemu_file copy during postcopy, which is
|
|
* going to do a copy later; can only do it when we
|
|
* do this read in one go (matching page sizes)
|
|
*/
|
|
qemu_get_buffer_in_place(f, (uint8_t **)&place_source,
|
|
TARGET_PAGE_SIZE);
|
|
}
|
|
break;
|
|
case RAM_SAVE_FLAG_EOS:
|
|
/* normal exit */
|
|
break;
|
|
default:
|
|
error_report("Unknown combination of migration flags: %#x"
|
|
" (postcopy mode)", flags);
|
|
ret = -EINVAL;
|
|
break;
|
|
}
|
|
|
|
/* Detect for any possible file errors */
|
|
if (!ret && qemu_file_get_error(f)) {
|
|
ret = qemu_file_get_error(f);
|
|
}
|
|
|
|
if (!ret && place_needed) {
|
|
/* This gets called at the last target page in the host page */
|
|
void *place_dest = host + TARGET_PAGE_SIZE - block->page_size;
|
|
|
|
if (all_zero) {
|
|
ret = postcopy_place_page_zero(mis, place_dest,
|
|
block);
|
|
} else {
|
|
ret = postcopy_place_page(mis, place_dest,
|
|
place_source, block);
|
|
}
|
|
}
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
static bool postcopy_is_advised(void)
|
|
{
|
|
PostcopyState ps = postcopy_state_get();
|
|
return ps >= POSTCOPY_INCOMING_ADVISE && ps < POSTCOPY_INCOMING_END;
|
|
}
|
|
|
|
static bool postcopy_is_running(void)
|
|
{
|
|
PostcopyState ps = postcopy_state_get();
|
|
return ps >= POSTCOPY_INCOMING_LISTENING && ps < POSTCOPY_INCOMING_END;
|
|
}
|
|
|
|
static int ram_load(QEMUFile *f, void *opaque, int version_id)
|
|
{
|
|
int flags = 0, ret = 0, invalid_flags = 0;
|
|
static uint64_t seq_iter;
|
|
int len = 0;
|
|
/*
|
|
* If system is running in postcopy mode, page inserts to host memory must
|
|
* be atomic
|
|
*/
|
|
bool postcopy_running = postcopy_is_running();
|
|
/* ADVISE is earlier, it shows the source has the postcopy capability on */
|
|
bool postcopy_advised = postcopy_is_advised();
|
|
|
|
seq_iter++;
|
|
|
|
if (version_id != 4) {
|
|
ret = -EINVAL;
|
|
}
|
|
|
|
if (!migrate_use_compression()) {
|
|
invalid_flags |= RAM_SAVE_FLAG_COMPRESS_PAGE;
|
|
}
|
|
/* This RCU critical section can be very long running.
|
|
* When RCU reclaims in the code start to become numerous,
|
|
* it will be necessary to reduce the granularity of this
|
|
* critical section.
|
|
*/
|
|
rcu_read_lock();
|
|
|
|
if (postcopy_running) {
|
|
ret = ram_load_postcopy(f);
|
|
}
|
|
|
|
while (!postcopy_running && !ret && !(flags & RAM_SAVE_FLAG_EOS)) {
|
|
ram_addr_t addr, total_ram_bytes;
|
|
void *host = NULL;
|
|
uint8_t ch;
|
|
|
|
addr = qemu_get_be64(f);
|
|
flags = addr & ~TARGET_PAGE_MASK;
|
|
addr &= TARGET_PAGE_MASK;
|
|
|
|
if (flags & invalid_flags) {
|
|
if (flags & invalid_flags & RAM_SAVE_FLAG_COMPRESS_PAGE) {
|
|
error_report("Received an unexpected compressed page");
|
|
}
|
|
|
|
ret = -EINVAL;
|
|
break;
|
|
}
|
|
|
|
if (flags & (RAM_SAVE_FLAG_ZERO | RAM_SAVE_FLAG_PAGE |
|
|
RAM_SAVE_FLAG_COMPRESS_PAGE | RAM_SAVE_FLAG_XBZRLE)) {
|
|
RAMBlock *block = ram_block_from_stream(f, flags);
|
|
|
|
host = host_from_ram_block_offset(block, addr);
|
|
if (!host) {
|
|
error_report("Illegal RAM offset " RAM_ADDR_FMT, addr);
|
|
ret = -EINVAL;
|
|
break;
|
|
}
|
|
ramblock_recv_bitmap_set(block, host);
|
|
trace_ram_load_loop(block->idstr, (uint64_t)addr, flags, host);
|
|
}
|
|
|
|
switch (flags & ~RAM_SAVE_FLAG_CONTINUE) {
|
|
case RAM_SAVE_FLAG_MEM_SIZE:
|
|
/* Synchronize RAM block list */
|
|
total_ram_bytes = addr;
|
|
while (!ret && total_ram_bytes) {
|
|
RAMBlock *block;
|
|
char id[256];
|
|
ram_addr_t length;
|
|
|
|
len = qemu_get_byte(f);
|
|
qemu_get_buffer(f, (uint8_t *)id, len);
|
|
id[len] = 0;
|
|
length = qemu_get_be64(f);
|
|
|
|
block = qemu_ram_block_by_name(id);
|
|
if (block && !qemu_ram_is_migratable(block)) {
|
|
error_report("block %s should not be migrated !", id);
|
|
ret = -EINVAL;
|
|
} else if (block) {
|
|
if (length != block->used_length) {
|
|
Error *local_err = NULL;
|
|
|
|
ret = qemu_ram_resize(block, length,
|
|
&local_err);
|
|
if (local_err) {
|
|
error_report_err(local_err);
|
|
}
|
|
}
|
|
/* For postcopy we need to check hugepage sizes match */
|
|
if (postcopy_advised &&
|
|
block->page_size != qemu_host_page_size) {
|
|
uint64_t remote_page_size = qemu_get_be64(f);
|
|
if (remote_page_size != block->page_size) {
|
|
error_report("Mismatched RAM page size %s "
|
|
"(local) %zd != %" PRId64,
|
|
id, block->page_size,
|
|
remote_page_size);
|
|
ret = -EINVAL;
|
|
}
|
|
}
|
|
ram_control_load_hook(f, RAM_CONTROL_BLOCK_REG,
|
|
block->idstr);
|
|
} else {
|
|
error_report("Unknown ramblock \"%s\", cannot "
|
|
"accept migration", id);
|
|
ret = -EINVAL;
|
|
}
|
|
|
|
total_ram_bytes -= length;
|
|
}
|
|
break;
|
|
|
|
case RAM_SAVE_FLAG_ZERO:
|
|
ch = qemu_get_byte(f);
|
|
ram_handle_compressed(host, ch, TARGET_PAGE_SIZE);
|
|
break;
|
|
|
|
case RAM_SAVE_FLAG_PAGE:
|
|
qemu_get_buffer(f, host, TARGET_PAGE_SIZE);
|
|
break;
|
|
|
|
case RAM_SAVE_FLAG_COMPRESS_PAGE:
|
|
len = qemu_get_be32(f);
|
|
if (len < 0 || len > compressBound(TARGET_PAGE_SIZE)) {
|
|
error_report("Invalid compressed data length: %d", len);
|
|
ret = -EINVAL;
|
|
break;
|
|
}
|
|
decompress_data_with_multi_threads(f, host, len);
|
|
break;
|
|
|
|
case RAM_SAVE_FLAG_XBZRLE:
|
|
if (load_xbzrle(f, addr, host) < 0) {
|
|
error_report("Failed to decompress XBZRLE page at "
|
|
RAM_ADDR_FMT, addr);
|
|
ret = -EINVAL;
|
|
break;
|
|
}
|
|
break;
|
|
case RAM_SAVE_FLAG_EOS:
|
|
/* normal exit */
|
|
break;
|
|
default:
|
|
if (flags & RAM_SAVE_FLAG_HOOK) {
|
|
ram_control_load_hook(f, RAM_CONTROL_HOOK, NULL);
|
|
} else {
|
|
error_report("Unknown combination of migration flags: %#x",
|
|
flags);
|
|
ret = -EINVAL;
|
|
}
|
|
}
|
|
if (!ret) {
|
|
ret = qemu_file_get_error(f);
|
|
}
|
|
}
|
|
|
|
ret |= wait_for_decompress_done();
|
|
rcu_read_unlock();
|
|
trace_ram_load_complete(ret, seq_iter);
|
|
return ret;
|
|
}
|
|
|
|
static bool ram_has_postcopy(void *opaque)
|
|
{
|
|
return migrate_postcopy_ram();
|
|
}
|
|
|
|
/* Sync all the dirty bitmap with destination VM. */
|
|
static int ram_dirty_bitmap_sync_all(MigrationState *s, RAMState *rs)
|
|
{
|
|
RAMBlock *block;
|
|
QEMUFile *file = s->to_dst_file;
|
|
int ramblock_count = 0;
|
|
|
|
trace_ram_dirty_bitmap_sync_start();
|
|
|
|
RAMBLOCK_FOREACH(block) {
|
|
qemu_savevm_send_recv_bitmap(file, block->idstr);
|
|
trace_ram_dirty_bitmap_request(block->idstr);
|
|
ramblock_count++;
|
|
}
|
|
|
|
trace_ram_dirty_bitmap_sync_wait();
|
|
|
|
/* Wait until all the ramblocks' dirty bitmap synced */
|
|
while (ramblock_count--) {
|
|
qemu_sem_wait(&s->rp_state.rp_sem);
|
|
}
|
|
|
|
trace_ram_dirty_bitmap_sync_complete();
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void ram_dirty_bitmap_reload_notify(MigrationState *s)
|
|
{
|
|
qemu_sem_post(&s->rp_state.rp_sem);
|
|
}
|
|
|
|
/*
|
|
* Read the received bitmap, revert it as the initial dirty bitmap.
|
|
* This is only used when the postcopy migration is paused but wants
|
|
* to resume from a middle point.
|
|
*/
|
|
int ram_dirty_bitmap_reload(MigrationState *s, RAMBlock *block)
|
|
{
|
|
int ret = -EINVAL;
|
|
QEMUFile *file = s->rp_state.from_dst_file;
|
|
unsigned long *le_bitmap, nbits = block->used_length >> TARGET_PAGE_BITS;
|
|
uint64_t local_size = nbits / 8;
|
|
uint64_t size, end_mark;
|
|
|
|
trace_ram_dirty_bitmap_reload_begin(block->idstr);
|
|
|
|
if (s->state != MIGRATION_STATUS_POSTCOPY_RECOVER) {
|
|
error_report("%s: incorrect state %s", __func__,
|
|
MigrationStatus_str(s->state));
|
|
return -EINVAL;
|
|
}
|
|
|
|
/*
|
|
* Note: see comments in ramblock_recv_bitmap_send() on why we
|
|
* need the endianess convertion, and the paddings.
|
|
*/
|
|
local_size = ROUND_UP(local_size, 8);
|
|
|
|
/* Add paddings */
|
|
le_bitmap = bitmap_new(nbits + BITS_PER_LONG);
|
|
|
|
size = qemu_get_be64(file);
|
|
|
|
/* The size of the bitmap should match with our ramblock */
|
|
if (size != local_size) {
|
|
error_report("%s: ramblock '%s' bitmap size mismatch "
|
|
"(0x%"PRIx64" != 0x%"PRIx64")", __func__,
|
|
block->idstr, size, local_size);
|
|
ret = -EINVAL;
|
|
goto out;
|
|
}
|
|
|
|
size = qemu_get_buffer(file, (uint8_t *)le_bitmap, local_size);
|
|
end_mark = qemu_get_be64(file);
|
|
|
|
ret = qemu_file_get_error(file);
|
|
if (ret || size != local_size) {
|
|
error_report("%s: read bitmap failed for ramblock '%s': %d"
|
|
" (size 0x%"PRIx64", got: 0x%"PRIx64")",
|
|
__func__, block->idstr, ret, local_size, size);
|
|
ret = -EIO;
|
|
goto out;
|
|
}
|
|
|
|
if (end_mark != RAMBLOCK_RECV_BITMAP_ENDING) {
|
|
error_report("%s: ramblock '%s' end mark incorrect: 0x%"PRIu64,
|
|
__func__, block->idstr, end_mark);
|
|
ret = -EINVAL;
|
|
goto out;
|
|
}
|
|
|
|
/*
|
|
* Endianess convertion. We are during postcopy (though paused).
|
|
* The dirty bitmap won't change. We can directly modify it.
|
|
*/
|
|
bitmap_from_le(block->bmap, le_bitmap, nbits);
|
|
|
|
/*
|
|
* What we received is "received bitmap". Revert it as the initial
|
|
* dirty bitmap for this ramblock.
|
|
*/
|
|
bitmap_complement(block->bmap, block->bmap, nbits);
|
|
|
|
trace_ram_dirty_bitmap_reload_complete(block->idstr);
|
|
|
|
/*
|
|
* We succeeded to sync bitmap for current ramblock. If this is
|
|
* the last one to sync, we need to notify the main send thread.
|
|
*/
|
|
ram_dirty_bitmap_reload_notify(s);
|
|
|
|
ret = 0;
|
|
out:
|
|
g_free(le_bitmap);
|
|
return ret;
|
|
}
|
|
|
|
static int ram_resume_prepare(MigrationState *s, void *opaque)
|
|
{
|
|
RAMState *rs = *(RAMState **)opaque;
|
|
int ret;
|
|
|
|
ret = ram_dirty_bitmap_sync_all(s, rs);
|
|
if (ret) {
|
|
return ret;
|
|
}
|
|
|
|
ram_state_resume_prepare(rs, s->to_dst_file);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static SaveVMHandlers savevm_ram_handlers = {
|
|
.save_setup = ram_save_setup,
|
|
.save_live_iterate = ram_save_iterate,
|
|
.save_live_complete_postcopy = ram_save_complete,
|
|
.save_live_complete_precopy = ram_save_complete,
|
|
.has_postcopy = ram_has_postcopy,
|
|
.save_live_pending = ram_save_pending,
|
|
.load_state = ram_load,
|
|
.save_cleanup = ram_save_cleanup,
|
|
.load_setup = ram_load_setup,
|
|
.load_cleanup = ram_load_cleanup,
|
|
.resume_prepare = ram_resume_prepare,
|
|
};
|
|
|
|
void ram_mig_init(void)
|
|
{
|
|
qemu_mutex_init(&XBZRLE.lock);
|
|
register_savevm_live(NULL, "ram", 0, 4, &savevm_ram_handlers, &ram_state);
|
|
}
|