From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:52304) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1a9AYg-00010O-Vt for qemu-devel@nongnu.org; Wed, 16 Dec 2015 06:47:54 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1a9AYf-0006Nm-UO for qemu-devel@nongnu.org; Wed, 16 Dec 2015 06:47:50 -0500 Received: from mx1.redhat.com ([209.132.183.28]:40194) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1a9AYf-0006Nf-PF for qemu-devel@nongnu.org; Wed, 16 Dec 2015 06:47:49 -0500 From: "Dr. David Alan Gilbert (git)" Date: Wed, 16 Dec 2015 11:47:37 +0000 Message-Id: <1450266458-3178-6-git-send-email-dgilbert@redhat.com> In-Reply-To: <1450266458-3178-1-git-send-email-dgilbert@redhat.com> References: <1450266458-3178-1-git-send-email-dgilbert@redhat.com> Subject: [Qemu-devel] [PATCH v2 5/6] Use qemu_get_buffer_in_place for xbzrle data List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org, quintela@redhat.com, amit.shah@redhat.com Cc: jdenemar@redhat.com, liang.z.li@intel.com, zhang.zhanghailiang@huawei.com From: "Dr. David Alan Gilbert" Avoid a data copy (if we're lucky) in the xbzrle code. Signed-off-by: Dr. David Alan Gilbert Reviewed-by: Juan Quintela --- migration/ram.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/migration/ram.c b/migration/ram.c index 102d1f2..994552c 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -2088,10 +2088,12 @@ static int load_xbzrle(QEMUFile *f, ram_addr_t addr, void *host) { unsigned int xh_len; int xh_flags; + uint8_t *loaded_data; if (!xbzrle_decoded_buf) { xbzrle_decoded_buf = g_malloc(TARGET_PAGE_SIZE); } + loaded_data = xbzrle_decoded_buf; /* extract RLE header */ xh_flags = qemu_get_byte(f); @@ -2107,10 +2109,10 @@ static int load_xbzrle(QEMUFile *f, ram_addr_t addr, void *host) return -1; } /* load data and decode */ - qemu_get_buffer(f, xbzrle_decoded_buf, xh_len); + qemu_get_buffer_in_place(f, &loaded_data, xh_len); /* decode RLE */ - if (xbzrle_decode_buffer(xbzrle_decoded_buf, xh_len, host, + if (xbzrle_decode_buffer(loaded_data, xh_len, host, TARGET_PAGE_SIZE) == -1) { error_report("Failed to load XBZRLE page - decode error!"); return -1; -- 2.5.0