Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753548AbYCIQ40 (ORCPT ); Sun, 9 Mar 2008 12:56:26 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751659AbYCIQ4R (ORCPT ); Sun, 9 Mar 2008 12:56:17 -0400 Received: from fg-out-1718.google.com ([72.14.220.152]:51458 "EHLO fg-out-1718.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751594AbYCIQ4R (ORCPT ); Sun, 9 Mar 2008 12:56:17 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=from:to:cc:subject:date:message-id:x-mailer:in-reply-to:references; b=eZJOsBaFk3lcFXUakrHKM3GtyPn+vpkx5sFiGFKf3MfdslMcimlao2rAZHLuwJCsr3OGTsgqFG8LOHE7dZL6sEiWlbpsoPZMrVd3K08gH2FfKFpJGZ8mrSV4lqwcAHsp6T4pi/OZy+XJv0tWfQrCx/yz405PUXb+XLLNN8RxI4s= From: Marcin Slusarz To: LKML Cc: Mauro Carvalho Chehab , v4l-dvb-maintainer@linuxtv.org, video4linux-list@redhat.com, Jean Delvare Subject: [PATCH 3/3] v4l: reduce stack usage of v4l1_compat_sync Date: Sun, 9 Mar 2008 17:55:55 +0100 Message-Id: <1205081755-18455-1-git-send-email-marcin.slusarz@gmail.com> X-Mailer: git-send-email 1.5.3.7 In-Reply-To: <1205081266-18368-1-git-send-email-marcin.slusarz@gmail.com> References: <1205081266-18368-1-git-send-email-marcin.slusarz@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2521 Lines: 79 poll_one allocated on stack struct poll_wqueues which is pretty big structure (>500 bytes on x86_64). v4l1_compat_sync invokes poll_one in a loop, so allocate struct poll_wqueues in v4l1_compat_sync (with kmalloc) and pass it to poll_one. Signed-off-by: Marcin Slusarz Cc: Mauro Carvalho Chehab --- drivers/media/video/v4l1-compat.c | 14 ++++++++------ 1 files changed, 8 insertions(+), 6 deletions(-) diff --git a/drivers/media/video/v4l1-compat.c b/drivers/media/video/v4l1-compat.c index aa73472..9f73d52 100644 --- a/drivers/media/video/v4l1-compat.c +++ b/drivers/media/video/v4l1-compat.c @@ -199,14 +199,13 @@ pixelformat_to_palette(unsigned int pixelformat) /* ----------------------------------------------------------------- */ -static int poll_one(struct file *file) +static int poll_one(struct file *file, struct poll_wqueues *pwq) { int retval = 1; poll_table *table; - struct poll_wqueues pwq; /*TODO: allocate dynamically*/ - poll_initwait(&pwq); - table = &pwq.pt; + poll_initwait(pwq); + table = &pwq->pt; for (;;) { int mask; set_current_state(TASK_INTERRUPTIBLE); @@ -221,7 +220,7 @@ static int poll_one(struct file *file) schedule(); } set_current_state(TASK_RUNNING); - poll_freewait(&pwq); + poll_freewait(pwq); return retval; } @@ -1043,6 +1042,7 @@ static noinline int v4l1_compat_sync( int err; enum v4l2_buf_type captype = V4L2_BUF_TYPE_VIDEO_CAPTURE; struct v4l2_buffer buf; + struct poll_wqueues *pwq; memset(&buf, 0, sizeof(buf)); buf.index = *i; @@ -1066,10 +1066,11 @@ static noinline int v4l1_compat_sync( goto done; } + pwq = kmalloc(sizeof(*pwq), GFP_KERNEL); /* Loop as long as the buffer is queued, but not done */ while ((buf.flags & (V4L2_BUF_FLAG_QUEUED | V4L2_BUF_FLAG_DONE)) == V4L2_BUF_FLAG_QUEUED) { - err = poll_one(file); + err = poll_one(file, pwq); if (err < 0 || /* error or sleep was interrupted */ err == 0) /* timeout? Shouldn't occur. */ break; @@ -1077,6 +1078,7 @@ static noinline int v4l1_compat_sync( if (err < 0) dprintk("VIDIOCSYNC / VIDIOC_QUERYBUF: %d\n", err); } + kfree(pwq); if (!(buf.flags & V4L2_BUF_FLAG_DONE)) /* not done */ goto done; do { -- 1.5.3.7 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/