From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:56135) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Zf26u-0000JV-PU for qemu-devel@nongnu.org; Thu, 24 Sep 2015 04:42:37 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Zf26s-00068E-S9 for qemu-devel@nongnu.org; Thu, 24 Sep 2015 04:42:36 -0400 Received: from mx1.redhat.com ([209.132.183.28]:59803) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Zf26s-000688-Mm for qemu-devel@nongnu.org; Thu, 24 Sep 2015 04:42:34 -0400 From: Gerd Hoffmann Date: Thu, 24 Sep 2015 10:42:01 +0200 Message-Id: <1443084128-25552-4-git-send-email-kraxel@redhat.com> In-Reply-To: <1443084128-25552-1-git-send-email-kraxel@redhat.com> References: <1443084128-25552-1-git-send-email-kraxel@redhat.com> Subject: [Qemu-devel] [RfC PATCH 03/10] vnc: make the Buffer capacity increase in powers of two List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Peter Lieven , Gerd Hoffmann From: Peter Lieven This makes sure the number of reallocs is in O(log N). Signed-off-by: Peter Lieven [ rebased to io/buffer.c ] Signed-off-by: Gerd Hoffmann --- io/buffer.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/io/buffer.c b/io/buffer.c index 68ae68d..6aa06e7 100644 --- a/io/buffer.c +++ b/io/buffer.c @@ -20,10 +20,13 @@ #include "io/buffer.h" +#define QIO_BUFFER_MIN_INIT_SIZE 4096 + void qio_buffer_reserve(QIOBuffer *buffer, size_t len) { if ((buffer->capacity - buffer->offset) < len) { - buffer->capacity += (len + 1024); + buffer->capacity = pow2ceil(buffer->offset + len); + buffer->capacity = MAX(buffer->capacity, QIO_BUFFER_MIN_INIT_SIZE); buffer->buffer = g_realloc(buffer->buffer, buffer->capacity); } } -- 1.8.3.1