From: Oleg Nesterov <oleg@redhat.com>
To: Eric Paris <eparis@redhat.com>
Cc: linux-mips@linux-mips.org, linux-ia64@vger.kernel.org,
linux-sh@vger.kernel.org, heiko.carstens@de.ibm.com,
paulus@samba.org, hpa@zytor.com, sparclinux@vger.kernel.org,
linux-s390@vger.kernel.org, richard@nod.at, x86@kernel.org,
mingo@redhat.com, fenghua.yu@intel.com,
user-mode-linux-devel@lists.sourceforge.net,
microblaze-uclinux@itee.uq.edu.au, jdike@addtoit.com,
viro@zeniv.linux.org.uk, tglx@linutronix.de, monstr@monstr.eu,
tony.luck@intel.com, linux-kernel@vger.kernel.org,
ralf@linux-mips.org, lethal@linux-sh.org, schwidefsky@de.ibm.com,
linux390@de.ibm.com, akpm@linux-foundation.org,
linuxppc-dev@lists.ozlabs.org, davem@davemloft.net
Subject: Re: [PATCH -v2] Audit: push audit success and retcode into arch ptrace.h
Date: Wed, 8 Jun 2011 20:37:20 +0200 [thread overview]
Message-ID: <20110608183720.GA16883@redhat.com> (raw)
In-Reply-To: <1307556823.2577.5.camel@localhost.localdomain>
On 06/08, Eric Paris wrote:
>
> On Wed, 2011-06-08 at 18:36 +0200, Oleg Nesterov wrote:
> > And I guess, all CONFIG_AUDITSYSCALL code in entry.S is only needed to
> > microoptimize the case when TIF_SYSCALL_AUDIT is the only reason for the
> > slow path. I wonder if it really makes the measureble difference...
>
> All I know is what Roland put in the changelog:
>
> Avoiding the iret return path when syscall audit is enabled helps
> performance a lot.
>
> I believe this was a result of Fedora starting auditd by default and
> then Linus bitching about how slow a null syscall in a tight loop was.
> It was an optimization for a microbenchmark. How much it affects things
> on a real syscall that does real work is probably going to be determined
> by how much work is done in the syscall.
and probably by how much work is done in audit_syscall_entry/exit.
OK. Thanks a lot Eric for your explanations.
Oleg.
next prev parent reply other threads:[~2011-06-08 18:39 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-06-03 22:04 [PATCH -v2] Audit: push audit success and retcode into arch ptrace.h Eric Paris
2011-06-03 22:52 ` Tony Luck
2011-06-04 22:36 ` Richard Weinberger
2011-06-06 20:17 ` David Miller
2011-06-07 17:19 ` Oleg Nesterov
2011-06-07 18:53 ` Eric Paris
2011-06-08 16:36 ` Oleg Nesterov
2011-06-08 18:13 ` Eric Paris
2011-06-08 18:37 ` Oleg Nesterov [this message]
2011-06-08 19:19 ` Oleg Nesterov
2011-06-08 14:04 ` Ralf Baechle
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=20110608183720.GA16883@redhat.com \
--to=oleg@redhat.com \
--cc=akpm@linux-foundation.org \
--cc=davem@davemloft.net \
--cc=eparis@redhat.com \
--cc=fenghua.yu@intel.com \
--cc=heiko.carstens@de.ibm.com \
--cc=hpa@zytor.com \
--cc=jdike@addtoit.com \
--cc=lethal@linux-sh.org \
--cc=linux-ia64@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mips@linux-mips.org \
--cc=linux-s390@vger.kernel.org \
--cc=linux-sh@vger.kernel.org \
--cc=linux390@de.ibm.com \
--cc=linuxppc-dev@lists.ozlabs.org \
--cc=microblaze-uclinux@itee.uq.edu.au \
--cc=mingo@redhat.com \
--cc=monstr@monstr.eu \
--cc=paulus@samba.org \
--cc=ralf@linux-mips.org \
--cc=richard@nod.at \
--cc=schwidefsky@de.ibm.com \
--cc=sparclinux@vger.kernel.org \
--cc=tglx@linutronix.de \
--cc=tony.luck@intel.com \
--cc=user-mode-linux-devel@lists.sourceforge.net \
--cc=viro@zeniv.linux.org.uk \
--cc=x86@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).