From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from [140.186.70.92] (port=40017 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1Om51L-0007sn-4y for qemu-devel@nongnu.org; Thu, 19 Aug 2010 09:19:04 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.69) (envelope-from ) id 1Om51J-0000xL-Ui for qemu-devel@nongnu.org; Thu, 19 Aug 2010 09:19:03 -0400 Received: from mx1.redhat.com ([209.132.183.28]:47954) by eggs.gnu.org with esmtp (Exim 4.69) (envelope-from ) id 1Om51J-0000xB-OU for qemu-devel@nongnu.org; Thu, 19 Aug 2010 09:19:01 -0400 From: Luiz Capitulino Date: Thu, 19 Aug 2010 10:18:40 -0300 Message-Id: <1282223922-5971-3-git-send-email-lcapitulino@redhat.com> In-Reply-To: <1282223922-5971-1-git-send-email-lcapitulino@redhat.com> References: <1282223922-5971-1-git-send-email-lcapitulino@redhat.com> Subject: [Qemu-devel] [PATCH 2/4] QEMUFileBuffered: indicate that we're ready when the underlying file is ready List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: aliguori@us.ibm.com Cc: qemu-devel@nongnu.org, Avi Kivity From: Avi Kivity QEMUFileBuffered stops writing when the underlying QEMUFile is not ready, and tells its producer so. However, when the underlying QEMUFile becomes ready, it neglects to pass that information along, resulting in stoppage of all data until the next tick (a tenths of a second). Usually this doesn't matter, because most QEMUFiles used with QEMUFileBuffered are almost always ready, but in the case of exec: migration this is not true, due to the small pipe buffers used to connect to the target process. The result is very slow migration. Fix by detecting the readiness notification and propagating it. The detection is a little ugly since QEMUFile overloads put_buffer() to send it, but that's the suject for a different patch. Signed-off-by: Avi Kivity Signed-off-by: Luiz Capitulino --- buffered_file.c | 8 ++++++++ 1 files changed, 8 insertions(+), 0 deletions(-) diff --git a/buffered_file.c b/buffered_file.c index be147d6..1836e7e 100644 --- a/buffered_file.c +++ b/buffered_file.c @@ -156,6 +156,14 @@ static int buffered_put_buffer(void *opaque, const uint8_t *buf, int64_t pos, in offset = size; } + if (pos == 0 && size == 0) { + DPRINTF("file is ready\n"); + if (s->bytes_xfer <= s->xfer_limit) { + DPRINTF("notifying client\n"); + s->put_ready(s->opaque); + } + } + return offset; } -- 1.7.2.1.97.g3235b