All of lore.kernel.org
 help / color / mirror / Atom feed
From: "H. Peter Anvin" <hpa@zytor.com>
To: Andy Lutomirski <luto@amacapital.net>
Cc: Stefani Seibold <stefani@seibold.net>,
	Greg KH <gregkh@linuxfoundation.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	X86 ML <x86@kernel.org>, Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>, Andi Kleen <ak@linux.intel.com>,
	Andrea Arcangeli <aarcange@redhat.com>,
	John Stultz <john.stultz@linaro.org>,
	Pavel Emelyanov <xemul@parallels.com>,
	Cyrill Gorcunov <gorcunov@openvz.org>,
	andriy.shevchenko@linux.intel.com,
	Martin Runge <Martin.Runge@rohde-schwarz.com>,
	Andreas Brief <Andreas.Brief@rohde-schwarz.com>,
	Linus Torvalds <torvalds@linux-foundation.org>
Subject: Re: [PATCH 3/3] x86, vdso32: handle 32 bit vDSO larger one page
Date: Thu, 13 Mar 2014 11:08:24 -0700	[thread overview]
Message-ID: <5321F418.1030304@zytor.com> (raw)
In-Reply-To: <CALCETrVy3oW=qvJWbGtKTZ=0dZLjHtmBphPDnP1N8nLmXc=+9A@mail.gmail.com>

On 03/13/2014 10:28 AM, Andy Lutomirski wrote:
> 
> Does this mean you prefer the relocation approach to the compat vdso
> removal approach?  It seems like Linus is okay with either one.
> 

Actually, thinking about it, removing it is probably better:

a) gets rid of legacy code, making room for unification;
b) either way enabling compat support (either relocation or disabling
   the vdso) has a performance penalty for *all* processes.

The only way to avoid that is to have a vdso at a fixed addresses across
all processes, either in the fixmap or in the user area (presumably at
the very top.)

	-hpa


  reply	other threads:[~2014-03-13 18:09 UTC|newest]

Thread overview: 27+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-03-12 22:51 [PATCH 0/3] Improve 32 bit vDSO time Stefani Seibold
2014-03-12 22:51 ` [PATCH 1/3] x86, vdso32: undef CONFIG_OPTIMIZE_INLINING and CONFIG_X86_PPRO_FENCE Stefani Seibold
2014-03-12 22:51 ` [PATCH 2/3] x86, vdso32: remove vsyscall_32.c Stefani Seibold
2014-03-12 22:51 ` [PATCH 3/3] x86, vdso32: handle 32 bit vDSO larger one page Stefani Seibold
2014-03-12 22:58   ` H. Peter Anvin
2014-03-12 22:59     ` Andy Lutomirski
2014-03-13 15:53       ` H. Peter Anvin
2014-03-13 17:28         ` Andy Lutomirski
2014-03-13 18:08           ` H. Peter Anvin [this message]
2014-03-13 18:21             ` H. Peter Anvin
2014-03-13 18:32               ` Andy Lutomirski
2014-03-13 19:01                 ` H. Peter Anvin
     [not found]                 ` <CA+55aFyOp6V_tE-sXKVi+=6yVwHQb0sLWSNbk=N7KbhBrx9QhA@mail.gmail.com>
     [not found]                   ` <CA+55aFyCSL==4Ff4JT3uFKN_28mz92ef1L67-4OUGqHZ8HXUhg@mail.gmail.com>
2014-03-13 19:13                     ` Andy Lutomirski
     [not found]                       ` <CA+55aFwDn3zA0gEn2r3nJVPWuv-pLYyrj4=8_gt1xFTd2g_Dwg@mail.gmail.com>
2014-03-13 19:33                         ` H. Peter Anvin
     [not found]                           ` <CA+55aFxWsm=P5h1o=BNrwkcy2ZadFsVxpegxJ0rskPVcmo_Ljw@mail.gmail.com>
2014-03-13 19:58                             ` H. Peter Anvin
2014-03-13 21:00                               ` Andi Kleen
2014-03-13 21:04                                 ` H. Peter Anvin
2014-03-13 21:10                                   ` Andi Kleen
2014-03-13 21:48                                     ` Linus Torvalds
2014-03-18 14:22                                 ` OT: " Hans-Peter Jansen
2014-03-13 19:35                         ` Andy Lutomirski
2014-03-12 22:56 ` [PATCH 0/3] Improve 32 bit vDSO time Andy Lutomirski
2014-03-12 23:11   ` stefani
2014-03-13  3:48     ` H. Peter Anvin
2014-03-13  8:11       ` Stefani Seibold
2014-03-13 22:08         ` H. Peter Anvin
2014-03-14  6:24           ` Stefani Seibold

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=5321F418.1030304@zytor.com \
    --to=hpa@zytor.com \
    --cc=Andreas.Brief@rohde-schwarz.com \
    --cc=Martin.Runge@rohde-schwarz.com \
    --cc=aarcange@redhat.com \
    --cc=ak@linux.intel.com \
    --cc=andriy.shevchenko@linux.intel.com \
    --cc=gorcunov@openvz.org \
    --cc=gregkh@linuxfoundation.org \
    --cc=john.stultz@linaro.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=luto@amacapital.net \
    --cc=mingo@redhat.com \
    --cc=stefani@seibold.net \
    --cc=tglx@linutronix.de \
    --cc=torvalds@linux-foundation.org \
    --cc=x86@kernel.org \
    --cc=xemul@parallels.com \
    /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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.