From patchwork Wed Aug 24 03:12:49 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Umesh Deshpande X-Patchwork-Id: 1090632 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by demeter2.kernel.org (8.14.4/8.14.4) with ESMTP id p7O3DkHr018016 for ; Wed, 24 Aug 2011 03:13:47 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755990Ab1HXDNm (ORCPT ); Tue, 23 Aug 2011 23:13:42 -0400 Received: from mx1.redhat.com ([209.132.183.28]:15550 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754749Ab1HXDNj (ORCPT ); Tue, 23 Aug 2011 23:13:39 -0400 Received: from int-mx10.intmail.prod.int.phx2.redhat.com (int-mx10.intmail.prod.int.phx2.redhat.com [10.5.11.23]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id p7O3DaSD028605 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Tue, 23 Aug 2011 23:13:36 -0400 Received: from ns3.rdu.redhat.com (ns3.rdu.redhat.com [10.11.255.199]) by int-mx10.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id p7O3DaPs003928; Tue, 23 Aug 2011 23:13:36 -0400 Received: from umeshhome.redhat.com (vpn-11-16.rdu.redhat.com [10.11.11.16]) by ns3.rdu.redhat.com (8.13.8/8.13.8) with ESMTP id p7O3DXSM009641; Tue, 23 Aug 2011 23:13:35 -0400 From: Umesh Deshpande To: kvm@vger.kernel.org, qemu-devel@nongnu.org Cc: pbonzini@redhat.com, quintela@redhat.com, mtosatti@redhat.com, Umesh Deshpande Subject: [RFC PATCH v5 3/4] Separate migration bitmap Date: Tue, 23 Aug 2011 23:12:49 -0400 Message-Id: In-Reply-To: References: X-Scanned-By: MIMEDefang 2.68 on 10.5.11.23 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by milter-greylist-4.2.6 (demeter2.kernel.org [140.211.167.43]); Wed, 24 Aug 2011 03:13:47 +0000 (UTC) This patch creates a migration bitmap, which is periodically kept in sync with the qemu bitmap. A separate copy of the dirty bitmap for the migration avoids concurrent access to the qemu bitmap from iothread and migration thread. Signed-off-by: Umesh Deshpande --- arch_init.c | 17 ++++++++--------- cpu-all.h | 37 +++++++++++++++++++++++++++++++++++++ exec.c | 57 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 102 insertions(+), 9 deletions(-) diff --git a/arch_init.c b/arch_init.c index 9d02270..b5b852b 100644 --- a/arch_init.c +++ b/arch_init.c @@ -124,13 +124,13 @@ static int ram_save_block(QEMUFile *f) current_addr = block->offset + offset; do { - if (cpu_physical_memory_get_dirty(current_addr, MIGRATION_DIRTY_FLAG)) { + if (migration_bitmap_get_dirty(current_addr, MIGRATION_DIRTY_FLAG)) { uint8_t *p; int cont = (block == last_block) ? RAM_SAVE_FLAG_CONTINUE : 0; - cpu_physical_memory_reset_dirty(current_addr, - current_addr + TARGET_PAGE_SIZE, - MIGRATION_DIRTY_FLAG); + migration_bitmap_reset_dirty(current_addr, + current_addr + TARGET_PAGE_SIZE, + MIGRATION_DIRTY_FLAG); p = block->host + offset; @@ -187,7 +187,7 @@ static ram_addr_t ram_save_remaining(void) 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)) { + if (migration_bitmap_get_dirty(addr, MIGRATION_DIRTY_FLAG)) { count++; } } @@ -267,6 +267,8 @@ int ram_save_live(Monitor *mon, QEMUFile *f, int stage, void *opaque) return 0; } + sync_migration_bitmap(0, TARGET_PHYS_ADDR_MAX); + if (stage == 1) { RAMBlock *block; bytes_transferred = 0; @@ -279,10 +281,7 @@ int ram_save_live(Monitor *mon, QEMUFile *f, int stage, void *opaque) 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); - } + migration_bitmap_set_dirty(addr); } } diff --git a/cpu-all.h b/cpu-all.h index b85483f..8181f8b 100644 --- a/cpu-all.h +++ b/cpu-all.h @@ -935,6 +935,7 @@ typedef struct RAMBlock { typedef struct RAMList { QemuMutex mutex; /* Protects RAM block list */ uint8_t *phys_dirty; + uint8_t *migration_bitmap; /* Dedicated bitmap for migration thread */ uint32_t version; /* To detect ram block addition/removal */ QLIST_HEAD(ram, RAMBlock) blocks; QLIST_HEAD(, RAMBlock) blocks_mru; @@ -1009,8 +1010,44 @@ static inline void cpu_physical_memory_mask_dirty_range(ram_addr_t start, } } + + void cpu_physical_memory_reset_dirty(ram_addr_t start, ram_addr_t end, int dirty_flags); + +static inline int migration_bitmap_get_dirty(ram_addr_t addr, + int dirty_flags) +{ + return ram_list.migration_bitmap[addr >> TARGET_PAGE_BITS] & dirty_flags; +} + +static inline void migration_bitmap_set_dirty(ram_addr_t addr) +{ + ram_list.migration_bitmap[addr >> TARGET_PAGE_BITS] = 0xff; +} + +static inline void migration_bitmap_mask_dirty_range(ram_addr_t start, + int length, + int dirty_flags) +{ + int i, mask, len; + uint8_t *p; + + len = length >> TARGET_PAGE_BITS; + mask = ~dirty_flags; + p = ram_list.migration_bitmap + (start >> TARGET_PAGE_BITS); + for (i = 0; i < len; i++) { + p[i] &= mask; + } +} + + +void migration_bitmap_reset_dirty(ram_addr_t start, + ram_addr_t end, + int dirty_flags); + +void sync_migration_bitmap(ram_addr_t start, ram_addr_t end); + void cpu_tlb_update_dirty(CPUState *env); int cpu_physical_memory_set_dirty_tracking(int enable); diff --git a/exec.c b/exec.c index 7627483..8dfbdbc 100644 --- a/exec.c +++ b/exec.c @@ -2111,6 +2111,10 @@ void cpu_physical_memory_reset_dirty(ram_addr_t start, ram_addr_t end, abort(); } + if (kvm_enabled()) { + return; + } + for(env = first_cpu; env != NULL; env = env->next_cpu) { int mmu_idx; for (mmu_idx = 0; mmu_idx < NB_MMU_MODES; mmu_idx++) { @@ -2119,8 +2123,54 @@ void cpu_physical_memory_reset_dirty(ram_addr_t start, ram_addr_t end, start1, length); } } + +} + +void migration_bitmap_reset_dirty(ram_addr_t start, ram_addr_t end, + int dirty_flags) +{ + unsigned long length; + + start &= TARGET_PAGE_MASK; + end = TARGET_PAGE_ALIGN(end); + + length = end - start; + if (length == 0) { + return; + } + + migration_bitmap_mask_dirty_range(start, length, dirty_flags); +} + +/* Synchronizes migration bitmap with the qemu dirty bitmap. + * Called by acquiring the iothread mutex */ + +void sync_migration_bitmap(ram_addr_t start, ram_addr_t end) +{ + unsigned long length, len, i; + ram_addr_t addr; + start &= TARGET_PAGE_MASK; + end = TARGET_PAGE_ALIGN(end); + + length = end - start; + if (length == 0) { + return; + } + + len = length >> TARGET_PAGE_BITS; + for (i = 0; i < len; i++) { + addr = i << TARGET_PAGE_BITS; + if (cpu_physical_memory_get_dirty(addr, MIGRATION_DIRTY_FLAG)) { + migration_bitmap_set_dirty(addr); + cpu_physical_memory_reset_dirty(addr, addr + TARGET_PAGE_SIZE, + MIGRATION_DIRTY_FLAG); + } + } + } + + int cpu_physical_memory_set_dirty_tracking(int enable) { int ret = 0; @@ -2999,6 +3049,13 @@ ram_addr_t qemu_ram_alloc_from_ptr(DeviceState *dev, const char *name, memset(ram_list.phys_dirty + (new_block->offset >> TARGET_PAGE_BITS), 0xff, size >> TARGET_PAGE_BITS); + ram_list.migration_bitmap = qemu_realloc(ram_list.phys_dirty, + last_ram_offset() >> + TARGET_PAGE_BITS); + + memset(ram_list.migration_bitmap + (new_block->offset >> TARGET_PAGE_BITS), + 0xff, size >> TARGET_PAGE_BITS); + qemu_mutex_unlock_migthread(); if (kvm_enabled())