From c2688bae4f871f4ed17f7f415d1e08e8d5d3c18d Mon Sep 17 00:00:00 2001 From: Alex Williamson Date: Tue, 6 Jul 2010 22:28:51 -0300 Subject: [PATCH 13/24] savevm: Use RAM blocks for basis of migration RH-Author: Alex Williamson Message-id: <20100706222851.1033.84328.stgit@localhost.localdomain> Patchwork-id: 10516 O-Subject: [RHEL6.0 qemu-kvm PATCH 13/17] savevm: Use RAM blocks for basis of migration Bugzilla: 596328 RH-Acked-by: Juan Quintela RH-Acked-by: Amit Shah RH-Acked-by: Jes Sorensen Bugzilla: 596328 Upstream commit: e44359c35efbcd5ba9abf94bdd544a744046925a We don't want to assume a contiguous address space, so migrate based on RAM blocks instead of a fixed linear address map. This will allow us to have holes in the ram_addr_t namespace, so we can implement qemu_ram_free(). Signed-off-by: Alex Williamson Signed-off-by: Anthony Liguori --- vl.c | 67 +++++++++++++++++++++++++++++++++++++++++------------------------- 1 files changed, 42 insertions(+), 25 deletions(-) Signed-off-by: Eduardo Habkost --- vl.c | 67 +++++++++++++++++++++++++++++++++++++++++------------------------ 1 files changed, 42 insertions(+), 25 deletions(-) diff --git a/vl.c b/vl.c index 8947b4a..4e6f293 100644 --- a/vl.c +++ b/vl.c @@ -3047,13 +3047,19 @@ static int is_dup_page(uint8_t *page, uint8_t ch) static int ram_save_block(QEMUFile *f) { - static ram_addr_t current_addr = 0; - ram_addr_t saved_addr = current_addr; - ram_addr_t addr = 0; - uint64_t total_ram = ram_bytes_total(); + static RAMBlock *last_block = NULL; + static ram_addr_t last_offset = 0; + RAMBlock *block = last_block; + ram_addr_t offset = last_offset; + ram_addr_t current_addr; int found = 0; - while (addr < total_ram) { + if (!block) + block = QLIST_FIRST(&ram_list.blocks); + + current_addr = block->offset + offset; + + do { if (kvm_enabled() && current_addr == 0) { int r; r = kvm_update_dirty_pages_log(); @@ -3064,19 +3070,12 @@ static int ram_save_block(QEMUFile *f) } } if (cpu_physical_memory_get_dirty(current_addr, MIGRATION_DIRTY_FLAG)) { - RAMBlock *block; - ram_addr_t offset; uint8_t *p; cpu_physical_memory_reset_dirty(current_addr, current_addr + TARGET_PAGE_SIZE, MIGRATION_DIRTY_FLAG); - QLIST_FOREACH(block, &ram_list.blocks, next) { - if (current_addr - block->offset < block->length) - break; - } - offset = current_addr - block->offset; p = block->host + offset; if (is_dup_page(p, *p)) { @@ -3096,9 +3095,21 @@ static int ram_save_block(QEMUFile *f) found = 1; break; } - addr += TARGET_PAGE_SIZE; - current_addr = (saved_addr + addr) % total_ram; - } + + offset += TARGET_PAGE_SIZE; + if (offset >= block->length) { + offset = 0; + block = QLIST_NEXT(block, next); + if (!block) + block = QLIST_FIRST(&ram_list.blocks); + } + + current_addr = block->offset + offset; + + } while (current_addr != last_block->offset + last_offset); + + last_block = block; + last_offset = offset; return found; } @@ -3107,13 +3118,16 @@ static uint64_t bytes_transferred; static ram_addr_t ram_save_remaining(void) { - ram_addr_t addr; + RAMBlock *block; ram_addr_t count = 0; - uint64_t total_ram = ram_bytes_total(); - for (addr = 0; addr < total_ram; addr += TARGET_PAGE_SIZE) { - if (cpu_physical_memory_get_dirty(addr, MIGRATION_DIRTY_FLAG)) - count++; + QLIST_FOREACH(block, &ram_list.blocks, next) { + ram_addr_t addr; + for (addr = block->offset; addr < block->offset + block->length; + addr += TARGET_PAGE_SIZE) { + if (cpu_physical_memory_get_dirty(addr, MIGRATION_DIRTY_FLAG)) + count++; + } } return count; @@ -3159,19 +3173,22 @@ static int ram_save_live(Monitor *mon, QEMUFile *f, int stage, void *opaque) if (stage == 1) { RAMBlock *block; - uint64_t total_ram = ram_bytes_total(); bytes_transferred = 0; /* Make sure all dirty bits are set */ - for (addr = 0; addr < total_ram; addr += TARGET_PAGE_SIZE) { - if (!cpu_physical_memory_get_dirty(addr, MIGRATION_DIRTY_FLAG)) - cpu_physical_memory_set_dirty(addr); + QLIST_FOREACH(block, &ram_list.blocks, next) { + for (addr = block->offset; addr < block->offset + block->length; + addr += TARGET_PAGE_SIZE) { + if (!cpu_physical_memory_get_dirty(addr, + MIGRATION_DIRTY_FLAG)) + cpu_physical_memory_set_dirty(addr); + } } /* Enable dirty memory tracking */ cpu_physical_memory_set_dirty_tracking(1); - qemu_put_be64(f, total_ram | RAM_SAVE_FLAG_MEM_SIZE); + qemu_put_be64(f, ram_bytes_total() | RAM_SAVE_FLAG_MEM_SIZE); QLIST_FOREACH(block, &ram_list.blocks, next) { qemu_put_byte(f, strlen(block->idstr)); -- 1.7.0.3