From: Denys Vlasenko <vda.linux@googlemail.com>
To: Tejun Heo <tj@kernel.org>
Cc: Denys Vlasenko <dvlasenk@redhat.com>,
Oleg Nesterov <oleg@redhat.com>,
linux-kernel@vger.kernel.org
Subject: Re: Why I want PTRACE_O_TRACESTOP option
Date: Fri, 9 Sep 2011 07:54:50 +0200 [thread overview]
Message-ID: <201109090754.50272.vda.linux@googlemail.com> (raw)
In-Reply-To: <20110909001853.GA29319@htj.dyndns.org>
On Friday 09 September 2011 02:18, Tejun Heo wrote:
> Hello, Denys.
>
> On Thu, Sep 08, 2011 at 06:50:01PM +0200, Denys Vlasenko wrote:
> > Consider what will happen when a next ptrace fix will require
> > a way to change ptrace API at runtime. A new option will likely
> > be introduced, say, PTRACE_O_TRACEPONY, with next available
> > bit position 7, and perhaps some new event will be generated,
> > PTRACE_EVENT_PONY, with value.... yes, it can't be 7,
> > PTRACE_EVENT_STOP took it. So it will probably be 8.
>
> Then, just give it the next matching number.
My point is that previously, ptrace behavior was modified by setting
options. Why don't we use this mechanism? Why we invent a different
wheel? Ptrace is ugly as-is, why complicate it even further?
The argument was that SETOPTIONS wasn't suitable for modifying
attach behavior, but this is fixed by "set options on SEIZE"
patch. I don't see why we can't use options mechanist to affect
group-stop behavior now.
--
vda
next prev parent reply other threads:[~2011-09-09 5:54 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-09-08 16:50 Why I want PTRACE_O_TRACESTOP option Denys Vlasenko
2011-09-09 0:18 ` Tejun Heo
2011-09-09 5:45 ` Denys Vlasenko
2011-09-09 16:00 ` Oleg Nesterov
2011-09-10 23:43 ` Tejun Heo
2011-09-09 5:54 ` Denys Vlasenko [this message]
2011-09-09 12:26 ` Indan Zupancic
2011-09-09 13:01 ` Indan Zupancic
2011-09-09 16:46 ` Denys Vlasenko
2011-09-09 16:26 ` Oleg Nesterov
2011-09-09 23:09 ` Indan Zupancic
2011-09-10 1:17 ` Denys Vlasenko
2011-09-10 11:20 ` Pedro Alves
2011-09-11 0:58 ` Tejun Heo
2011-09-09 16:14 ` Oleg Nesterov
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=201109090754.50272.vda.linux@googlemail.com \
--to=vda.linux@googlemail.com \
--cc=dvlasenk@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=oleg@redhat.com \
--cc=tj@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).