Article View: fa.netbsd.tech.kern
Article #64Re: [GSoC 2013] Interested in "Light weight precision user level time reading"
From: zhixiang yu
Date: Mon, 15 Apr 2013 13:05
Date: Mon, 15 Apr 2013 13:05
21 lines
3689 bytes
3689 bytes
Sorry, re-post with plain text mode. Thanks someone for their kindly information. Hi List, I'm a graduate student from China. I'm interested in the NetBSD's "Light weight precision user level time reading" project. I'd like to take it as my GSoC 2013 project. But before sending the detailed proposal, I'd like listen to your advices/comments since my solution is a bit different: Allocate one special page on which the kernel and user-space process can share data such as bintime,etc. The kernel will update the shared data at some event point, the kernel will also need to tell which timecounter it's using. The userspace just reads out the bintime and read the timecounter to adjust the final result. Sure the concurrency between kernel and userspace should be resolved properly. What do you think about this solution? Is it acceptable? Thanks in advance
Technical Details
Message-ID:
<fa.NrExnLKQeSZdQUcU9PDVRKObdNA@ifi.uio.no>Path:
arc1-ca.pugleaf.net!hg5ni15550wib.1!nntp.google.com!feeder1.cambriumusenet.nl!feed.tweaknews.nl!85.12.40.130.MISMATCH!xlned.com!feeder1.xlned.com!border2.nntp.ams.giganews.com!border3.nntp.ams.giganews.com!border1.nntp.ams.giganews.com!nntp.giganews.com!news.nobody.at!goblin1!goblin.stu.neva.ru!uio.no!nntp.uio.no!.POSTED!not-for-mailReferences:
<fa.NavTrP2qnSjoMdtUs0zWDikl7iA@ifi.uio.no> <fa.7qDdDj14O28iM7hgnB5x8K8lH5s@ifi.uio.no>Show Full Headers
Complete Article Headers
X-Google-Thread: b7e13b6095,7f4e4fabf502ba0b
X-Google-Attributes: gidb7e13b6095,public,usenet
X-Google-NewGroupId: yes
X-Google-Language: ENGLISH,ASCII-7-bit
X-Received: by 10.180.182.229 with SMTP id eh5mr6652820wic.1.1366254634170;
Wed, 17 Apr 2013 20:10:34 -0700 (PDT)
Path: arc1-ca.pugleaf.net!hg5ni15550wib.1!nntp.google.com!feeder1.cambriumusenet.nl!feed.tweaknews.nl!85.12.40.130.MISMATCH!xlned.com!feeder1.xlned.com!border2.nntp.ams.giganews.com!border3.nntp.ams.giganews.com!border1.nntp.ams.giganews.com!nntp.giganews.com!news.nobody.at!goblin1!goblin.stu.neva.ru!uio.no!nntp.uio.no!.POSTED!not-for-mail
From: zhixiang yu <zxyu.core@gmail.com>
Newsgroups: fa.netbsd.tech.kern
Subject: Re: [GSoC 2013] Interested in "Light weight precision user level time reading"
Date: Mon, 15 Apr 2013 13:05:01 UTC
Organization: Internet mailing list
Lines: 21
Sender: tech-kern-owner@NetBSD.org
Message-ID: <fa.NrExnLKQeSZdQUcU9PDVRKObdNA@ifi.uio.no>
References: <fa.NavTrP2qnSjoMdtUs0zWDikl7iA@ifi.uio.no> <fa.7qDdDj14O28iM7hgnB5x8K8lH5s@ifi.uio.no>
NNTP-Posting-Host: mail-jess.uio.no
Mime-Version: 1.0
X-Trace: readme.uio.no 1366031101 14042 129.240.7.9 (15 Apr 2013 13:05:01 GMT)
X-Complaints-To: abuse@uio.no
NNTP-Posting-Date: Mon, 15 Apr 2013 13:05:01 +0000 (UTC)
Cc: christos@netbsd.org, tech-kern@netbsd.org
To: tech-userlevel@netbsd.org
Delivered-To: tech-kern@netbsd.org
X-Virus-Scanned: amavisd-new at NetBSD.org
Authentication-Results: mail.NetBSD.org (amavisd-new);
dkim=pass (2048-bit key) header.d=gmail.com
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
d=gmail.com; s=20120113;
h=mime-version:x-received:in-reply-to:references:date:message-id
:subject:from:to:cc:content-type;
bh=by1vcrOR6KmVEdggoEvv6VTTHUX/xnzxQ1oKxME7yVw=;
b=Sp5dhZi10nCGhckcYrJPuql9U7+d9H4kTIdhNMKXjWOmBAne/UhlaVxrZ1woEgFYa5
BvTOvk9zT80O7V/L8pHIYve4sXaKKEXbPJpRn1X0WguS3YJLhdDVlueYte4W/NgnW3Nk
3PS72I3iUcm3hsZY7LqC4ty2DJMgCsYnlWxfBBTLhhReXbnIp4IR4zq/9eJj//tnBNvh
ZXM8pz++2uPxFPQaeiu/OnlVSTt7LdVYbkdCvfd0Pt2LnDo6qTFaQdZXYiBvId3nxeMf
xQnmXsjOsvGq/LtsgBywD5IHNGBiXcKEfxEn7kpeN19AOejuHzkMtPTrwGrYVso1GYRI
qPJg==
X-Received: by 10.205.65.81 with SMTP id xl17mr8215955bkb.90.1366031082438;
Mon, 15 Apr 2013 06:04:42 -0700 (PDT)
In-Reply-To: <CADr9iNtsfvH6yJLkmAdzFnSH-U=1abRZdR_Bc+8ZyLK_FTnckw@mail.gmail.com>
List-Id: tech-kern.NetBSD.org
Original-Date: Mon, 15 Apr 2013 21:04:42 +0800
Original-Message-Id: <CADr9iNtYzgP2pLa+fUGNrPhpBUvZEu3a3UXg48H7WMqBmRvWoQ@mail.gmail.com>
Original-References: <CADr9iNuGq2UroYOhHKV8raYiF_aakXx-8wOyJNeFpBA10W8RUQ@mail.gmail.com>
<CADr9iNtsfvH6yJLkmAdzFnSH-U=1abRZdR_Bc+8ZyLK_FTnckw@mail.gmail.com>
Bytes: 3250
Content-Type: text/plain; charset=ISO-8859-1