From mboxrd@z Thu Jan 1 00:00:00 1970 From: Oleg Nesterov Subject: Re: [patch 050/160] prctl: add PR_SET_PROCTITLE_AREA option for prctl() Date: Tue, 9 Mar 2010 23:17:04 +0100 Message-ID: <20100309221704.GA1401@redhat.com> References: <201003052142.o25Lgbpg029522@imap1.linux-foundation.org> <20100306095705.GA26221@infradead.org> <20100309134105.7CDB.A69D9226@jp.fujitsu.com> <4B95DAF3.5050605@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <4B95DAF3.5050605-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> Sender: linux-api-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Ulrich Drepper Cc: KOSAKI Motohiro , Christoph Hellwig , akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org, torvalds-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org, bdonlan-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, hpa-YMNOUZJC4hwAvxtiuMwx3w@public.gmane.org, linux-api-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, mingo-X9Un+BFzKDI@public.gmane.org, tss-X3B1VOXEql0@public.gmane.org, xiyou.wangcong-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org List-Id: linux-api@vger.kernel.org On 03/08, Ulrich Drepper wrote: > > On 03/08/2010 08:44 PM, KOSAKI Motohiro wrote: > > I don't think this is big matter. Does using syscall have any benefit? > > I don't have strong mention. merely, Timo's original proposal used > > prctl. > > Syscalls don't have to go through the multiplexer in grab bag calls like > prctl, ioctl, etc. And they are more reliably to test for at runtime. > An ENOSYS error is unmistakably clear. An EINVAL error, as returned by > prctl when encountering an unknown function argument, could also mean > the argument isn't valid. That's a common problem of most multiplexer > syscalls and a reason why they should be avoided. Agreed, but this applies to any prtcl() request. And we already have PR_GET_NAME/PR_SET_NAME which is very close to PR_SET_PROCTITLE_AREA. So, do you really think that this particular case deserves the new syscall? Oleg.