From: "H. Peter Anvin" <hpa@zytor.com>
To: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
Andrew Morton <akpm@linux-foundation.org>,
Russell King <linux@arm.linux.org.uk>,
Thomas Gleixner <tglx@linutronix.de>,
Ingo Molnar <mingo@redhat.com>
Cc: linux-kernel@vger.kernel.org, linux-api@vger.kernel.org,
Paul Turner <pjt@google.com>, Andrew Hunter <ahh@google.com>,
Peter Zijlstra <peterz@infradead.org>,
Andy Lutomirski <luto@amacapital.net>,
Andi Kleen <andi@firstfloor.org>,
Dave Watson <davejwatson@fb.com>, Chris Lameter <cl@linux.com>,
Ben Maurer <bmaurer@fb.com>, Steven Rostedt <rostedt@goodmis.org>,
"Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
Josh Triplett <josh@joshtriplett.org>,
Linus Torvalds <torvalds@linux-foundation.org>,
Catalin Marinas <catalin.marinas@arm.com>,
Will Deacon <will.deacon@arm.com>,
Michael Kerrisk <mtk.manpages@gmail.com>
Subject: Re: [PATCH v4 0/5] getcpu_cache system call for 4.6
Date: Tue, 23 Feb 2016 17:36:26 -0800 [thread overview]
Message-ID: <56CD091A.4060009@zytor.com> (raw)
In-Reply-To: <1456270120-7560-1-git-send-email-mathieu.desnoyers@efficios.com>
On 02/23/2016 03:28 PM, Mathieu Desnoyers wrote:
> Hi,
>
> Here is a patchset implementing a cache for the CPU number of the
> currently running thread in user-space.
>
> Benchmarks comparing this approach to a getcpu based on system call on
> ARM show a 44x speedup. They show a 14x speedup on x86-64 compared to
> executing lsl from a vDSO through glibc.
>
> I'm added a man page in the changelog of patch 1/3, which shows an
> example usage of this new system call.
>
> This series is based on v4.5-rc5, submitted for Linux 4.6.
>
> Feedback is welcome,
>
What is the resulting context switch overhead?
-hpa
next prev parent reply other threads:[~2016-02-24 1:37 UTC|newest]
Thread overview: 55+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-02-23 23:28 [PATCH v4 0/5] getcpu_cache system call for 4.6 Mathieu Desnoyers
2016-02-23 23:28 ` [PATCH v4 1/5] getcpu_cache system call: cache CPU number of running thread Mathieu Desnoyers
2016-02-24 11:11 ` Thomas Gleixner
2016-02-24 17:17 ` Mathieu Desnoyers
2016-02-25 23:32 ` Rasmus Villemoes
2016-02-26 17:47 ` Mathieu Desnoyers
2016-02-25 9:56 ` Peter Zijlstra
2016-02-25 16:55 ` Mathieu Desnoyers
2016-02-25 17:04 ` Peter Zijlstra
2016-02-25 17:17 ` Mathieu Desnoyers
2016-02-26 11:33 ` Peter Zijlstra
2016-02-26 16:29 ` Thomas Gleixner
2016-02-26 17:20 ` Mathieu Desnoyers
2016-02-26 18:01 ` Thomas Gleixner
2016-02-26 20:24 ` Mathieu Desnoyers
2016-02-26 23:04 ` H. Peter Anvin
2016-02-27 0:40 ` Mathieu Desnoyers
2016-02-27 6:24 ` H. Peter Anvin
2016-02-27 14:15 ` Mathieu Desnoyers
2016-02-27 14:58 ` Peter Zijlstra
2016-02-27 18:35 ` Linus Torvalds
2016-02-27 19:01 ` H. Peter Anvin
2016-02-27 23:53 ` Mathieu Desnoyers
[not found] ` <CA+55aFwcgwRxvVBz5kk_3O8dESXAGJ4KHBkf=pSXjiS7Xh4NwA@mail.gmail.com>
[not found] ` <1082926946.10326.1456619994590.JavaMail.zimbra@efficios.com>
2016-02-28 0:57 ` Linus Torvalds
2016-02-28 14:32 ` Mathieu Desnoyers
2016-02-29 10:35 ` Peter Zijlstra
2016-03-01 20:23 ` Mathieu Desnoyers
2016-03-01 21:32 ` Peter Zijlstra
2016-03-01 21:36 ` Peter Zijlstra
2016-03-01 21:47 ` H. Peter Anvin
2016-03-02 10:34 ` Peter Zijlstra
2016-02-29 10:32 ` Peter Zijlstra
2016-02-29 10:39 ` Arnd Bergmann
2016-02-29 12:41 ` Mathieu Desnoyers
2016-02-29 13:08 ` Arnd Bergmann
2016-02-29 18:19 ` H. Peter Anvin
2016-03-02 10:44 ` Geert Uytterhoeven
2016-03-01 18:25 ` H. Peter Anvin
2016-03-01 18:40 ` Mathieu Desnoyers
2016-02-28 13:07 ` Geert Uytterhoeven
2016-02-28 16:21 ` Linus Torvalds
2016-02-29 10:01 ` Peter Zijlstra
2016-02-27 15:04 ` H. Peter Anvin
2016-02-23 23:28 ` [PATCH v4 2/5] getcpu_cache: ARM resume notifier Mathieu Desnoyers
2016-02-23 23:28 ` [PATCH v4 3/5] getcpu_cache: wire up ARM system call Mathieu Desnoyers
2016-02-24 0:54 ` kbuild test robot
2016-02-24 1:05 ` [PATCH v4 (updated)] " Mathieu Desnoyers
2016-02-24 5:28 ` kbuild test robot
2016-02-24 6:54 ` kbuild test robot
2016-02-23 23:28 ` [PATCH v4 4/5] getcpu_cache: x86 32/64 resume notifier Mathieu Desnoyers
2016-02-23 23:28 ` [PATCH v4 5/5] getcpu_cache: wire up x86 32/64 system call Mathieu Desnoyers
2016-02-24 1:36 ` H. Peter Anvin [this message]
2016-02-24 4:09 ` [PATCH v4 0/5] getcpu_cache system call for 4.6 Mathieu Desnoyers
2016-02-24 20:07 ` H. Peter Anvin
2016-02-24 22:38 ` Mathieu Desnoyers
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=56CD091A.4060009@zytor.com \
--to=hpa@zytor.com \
--cc=ahh@google.com \
--cc=akpm@linux-foundation.org \
--cc=andi@firstfloor.org \
--cc=bmaurer@fb.com \
--cc=catalin.marinas@arm.com \
--cc=cl@linux.com \
--cc=davejwatson@fb.com \
--cc=josh@joshtriplett.org \
--cc=linux-api@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux@arm.linux.org.uk \
--cc=luto@amacapital.net \
--cc=mathieu.desnoyers@efficios.com \
--cc=mingo@redhat.com \
--cc=mtk.manpages@gmail.com \
--cc=paulmck@linux.vnet.ibm.com \
--cc=peterz@infradead.org \
--cc=pjt@google.com \
--cc=rostedt@goodmis.org \
--cc=tglx@linutronix.de \
--cc=torvalds@linux-foundation.org \
--cc=will.deacon@arm.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 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).