{"id":2133,"url":"https://patchwork.libcamera.org/api/patches/2133/?format=json","web_url":"https://patchwork.libcamera.org/patch/2133/","project":{"id":1,"url":"https://patchwork.libcamera.org/api/projects/1/?format=json","name":"libcamera","link_name":"libcamera","list_id":"libcamera_core","list_email":"libcamera-devel@lists.libcamera.org","web_url":"","scm_url":"","webscm_url":""},"msgid":"<20191007224642.6597-6-laurent.pinchart@ideasonboard.com>","date":"2019-10-07T22:46:38","name":"[libcamera-devel,5/9] libcamera: v4l2_device: Avoid copy of V4L2ControlInfo","commit_ref":null,"pull_url":null,"state":"superseded","archived":false,"hash":"561bca3fcff520c58e42a4526c88bd1c23f0ccb3","submitter":{"id":2,"url":"https://patchwork.libcamera.org/api/people/2/?format=json","name":"Laurent Pinchart","email":"laurent.pinchart@ideasonboard.com"},"delegate":null,"mbox":"https://patchwork.libcamera.org/patch/2133/mbox/","series":[{"id":526,"url":"https://patchwork.libcamera.org/api/series/526/?format=json","web_url":"https://patchwork.libcamera.org/project/libcamera/list/?series=526","date":"2019-10-07T22:46:33","name":"Use ControlList for both libcamera and V4L2 controls","version":1,"mbox":"https://patchwork.libcamera.org/series/526/mbox/"}],"comments":"https://patchwork.libcamera.org/api/patches/2133/comments/","check":"pending","checks":"https://patchwork.libcamera.org/api/patches/2133/checks/","tags":{},"headers":{"Return-Path":"","Received":["from perceval.ideasonboard.com (perceval.ideasonboard.com\n\t[IPv6:2001:4b98:dc2:55:216:3eff:fef7:d647])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTPS id C4D176196D\n\tfor ;\n\tTue, 8 Oct 2019 00:46:55 +0200 (CEST)","from pendragon.ideasonboard.com\n\t(modemcable118.64-20-96.mc.videotron.ca [96.20.64.118])\n\tby perceval.ideasonboard.com (Postfix) with ESMTPSA id E91F2B2D\n\tfor ;\n\tTue, 8 Oct 2019 00:46:54 +0200 (CEST)"],"DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com;\n\ts=mail; t=1570488415;\n\tbh=GvIit0LxIGNZjzEkjapDquTGQEpfBw0NxtjXXLA+hFY=;\n\th=From:To:Subject:Date:In-Reply-To:References:From;\n\tb=pSQ+wzfBsBXRR+iTPCBerDupZLJtsHbOojGqx56e447JELFNUF1SLH5NMj4EzMFLL\n\tj1Q1lleYm39mSW4SNVp+5ekrXWulDzAMSoCPsyT89pfmQRS38Mod61avANr2ynCLQN\n\tmL+ITwVOCHBAq5omFaY6t9xnQCZX/hWtorCRaeqQ=","From":"Laurent Pinchart ","To":"libcamera-devel@lists.libcamera.org","Date":"Tue, 8 Oct 2019 01:46:38 +0300","Message-Id":"<20191007224642.6597-6-laurent.pinchart@ideasonboard.com>","X-Mailer":"git-send-email 2.21.0","In-Reply-To":"<20191007224642.6597-1-laurent.pinchart@ideasonboard.com>","References":"<20191007224642.6597-1-laurent.pinchart@ideasonboard.com>","MIME-Version":"1.0","Content-Transfer-Encoding":"8bit","Subject":"[libcamera-devel] [PATCH 5/9] libcamera: v4l2_device: Avoid copy of\n\tV4L2ControlInfo","X-BeenThere":"libcamera-devel@lists.libcamera.org","X-Mailman-Version":"2.1.29","Precedence":"list","List-Id":"","List-Unsubscribe":",\n\t","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n\t","X-List-Received-Date":"Mon, 07 Oct 2019 22:46:56 -0000"},"content":"The V4L2Device::listControls() method creates an instance of\nV4L2ControlInfo and then inserts it in the device's list of controls.\nThe insertion uses std::map::emplace(), but passes the V4L2ControlInfo,\nresulting in a copy being performed (using the copy constructor of\nV4L2ControlInfo).\n\nOptimise this by really constructing the V4L2ControlInfo emplace. The\nuse of std::piecewise_construct is required for gcc-5 that seems to have\ntrouble with std::map::emplace() on non-copyable values in this case.\n\nSigned-off-by: Laurent Pinchart \n---\n src/libcamera/v4l2_device.cpp | 9 +++++----\n 1 file changed, 5 insertions(+), 4 deletions(-)","diff":"diff --git a/src/libcamera/v4l2_device.cpp b/src/libcamera/v4l2_device.cpp\nindex fd4b9c6d5c62..3bd82ff23212 100644\n--- a/src/libcamera/v4l2_device.cpp\n+++ b/src/libcamera/v4l2_device.cpp\n@@ -352,8 +352,7 @@ void V4L2Device::listControls()\n \t\t ctrl.flags & V4L2_CTRL_FLAG_DISABLED)\n \t\t\tcontinue;\n \n-\t\tV4L2ControlInfo info(ctrl);\n-\t\tswitch (info.type()) {\n+\t\tswitch (ctrl.type) {\n \t\tcase V4L2_CTRL_TYPE_INTEGER:\n \t\tcase V4L2_CTRL_TYPE_BOOLEAN:\n \t\tcase V4L2_CTRL_TYPE_MENU:\n@@ -364,12 +363,14 @@ void V4L2Device::listControls()\n \t\t\tbreak;\n \t\t/* \\todo Support compound controls. */\n \t\tdefault:\n-\t\t\tLOG(V4L2, Debug) << \"Control type '\" << info.type()\n+\t\t\tLOG(V4L2, Debug) << \"Control type '\" << ctrl.type\n \t\t\t\t\t << \"' not supported\";\n \t\t\tcontinue;\n \t\t}\n \n-\t\tcontrols_.emplace(ctrl.id, info);\n+\t\tcontrols_.emplace(std::piecewise_construct,\n+\t\t\t\t std::forward_as_tuple(ctrl.id),\n+\t\t\t\t std::forward_as_tuple(ctrl));\n \t}\n }\n \n","prefixes":["libcamera-devel","5/9"]}