From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:45826) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SpaEU-000869-Uq for qemu-devel@nongnu.org; Fri, 13 Jul 2012 03:24:16 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1SpaET-0004Rb-Q9 for qemu-devel@nongnu.org; Fri, 13 Jul 2012 03:24:10 -0400 Received: from mx1.redhat.com ([209.132.183.28]:57595) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SpaET-0004RW-IT for qemu-devel@nongnu.org; Fri, 13 Jul 2012 03:24:09 -0400 Received: from int-mx01.intmail.prod.int.phx2.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id q6D7O9l3017727 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Fri, 13 Jul 2012 03:24:09 -0400 From: Juan Quintela Date: Fri, 13 Jul 2012 09:23:39 +0200 Message-Id: <1342164224-32709-18-git-send-email-quintela@redhat.com> In-Reply-To: <1342164224-32709-1-git-send-email-quintela@redhat.com> References: <1342164224-32709-1-git-send-email-quintela@redhat.com> Subject: [Qemu-devel] [PATCH 17/22] Change ram_save_block to return -1 if there are no more changes List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Orit Wasserman From: Orit Wasserman It will return 0 if the page is unmodifed. Signed-off-by: Orit Wasserman Signed-off-by: Juan Quintela --- arch_init.c | 26 ++++++++++++++++++++------ 1 file changed, 20 insertions(+), 6 deletions(-) diff --git a/arch_init.c b/arch_init.c index 8cbf8f4..78cdf50 100644 --- a/arch_init.c +++ b/arch_init.c @@ -184,11 +184,19 @@ static void save_block_hdr(QEMUFile *f, RAMBlock *block, ram_addr_t offset, static RAMBlock *last_block; static ram_addr_t last_offset; +/* + * ram_save_block: Writes a page of memory to the stream f + * + * Returns: 0: if the page hasn't changed + * -1: if there are no more dirty pages + * n: the amount of bytes written in other case + */ + static int ram_save_block(QEMUFile *f) { RAMBlock *block = last_block; ram_addr_t offset = last_offset; - int bytes_sent = 0; + int bytes_sent = -1; MemoryRegion *mr; if (!block) @@ -354,10 +362,11 @@ static int ram_save_iterate(QEMUFile *f, void *opaque) int bytes_sent; bytes_sent = ram_save_block(f); - bytes_transferred += bytes_sent; - if (bytes_sent == 0) { /* no more blocks */ + /* no more blocks to sent */ + if (bytes_sent < 0) { break; } + bytes_transferred += bytes_sent; /* 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 @@ -405,14 +414,19 @@ static int ram_save_iterate(QEMUFile *f, void *opaque) static int ram_save_complete(QEMUFile *f, void *opaque) { - int bytes_sent; - memory_global_sync_dirty_bitmap(get_system_memory()); /* try transferring iterative blocks of memory */ /* flush all remaining blocks regardless of rate limiting */ - while ((bytes_sent = ram_save_block(f)) != 0) { + while (true) { + int bytes_sent; + + bytes_sent = ram_save_block(f); + /* no more blocks to sent */ + if (bytes_sent < 0) { + break; + } bytes_transferred += bytes_sent; } memory_global_dirty_log_stop(); -- 1.7.10.4