mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Paolo Bonzini <pbonzini@redhat.com>
To: Andy Lutomirski <luto@amacapital.net>
Cc: Thomas Gleixner <tglx@linutronix.de>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	Ingo Molnar <mingo@kernel.org.com>,
	"H. Peter Anvin" <hpa@zytor.com>, X86 ML <x86@kernel.org>,
	Rik van Riel <riel@redhat.com>,
	Peter Zijlstra <peterz@infradead.org>
Subject: Re: [PATCH 1/2] x86/entry: Avoid interrupt flag save and restore
Date: Mon, 6 Jun 2016 17:47:52 +0200	[thread overview]
Message-ID: <0e02e304-a226-a35c-1109-25a35d4eae67@redhat.com> (raw)
In-Reply-To: <CALCETrUeAi7F2o3EGhOjEzWArO6P-AzoU1a+SsJ2O9060ELKaw@mail.gmail.com>



On 04/06/2016 07:07, Andy Lutomirski wrote:
> On May 30, 2016 5:30 AM, "Paolo Bonzini" <pbonzini@redhat.com> wrote:
>>
>> Thanks to all the work that was done by Andy Lutomirski and others,
>> enter_from_user_mode and prepare_exit_to_usermode are now called only with
>> interrupts disabled.  Let's provide them a version of user_enter/user_exit
>> that skips saving and restoring the interrupt flag.
> 
>> +/* Called with interrupts disabled.  */
>> +static inline void __user_enter(void)
>> +{
>> +       if (context_tracking_is_enabled())
>> +               __context_tracking_enter(CONTEXT_USER);
>> +
>> +}
> 
> Would user_enter_irqs_off be a better name?

I'm just mimicking __context_tracking_enter and vs.
context_tracking_enter.  So it is at least consistent with those functions.

The guest ones are not quite as consistent.  I can fix that later,
there's no reason also to have guest context tracking split between
include/linux/context_tracking.h and include/linux/kvm_host.h.

Thanks,

Paolo

  reply	other threads:[~2016-06-06 15:48 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-05-30 12:30 [PATCH 0/2] x86/entry: speed up context-tracking system calls by 150 clock cycles Paolo Bonzini
2016-05-30 12:30 ` [PATCH 1/2] x86/entry: Avoid interrupt flag save and restore Paolo Bonzini
2016-06-01 14:52   ` Rik van Riel
2016-06-04  5:07   ` Andy Lutomirski
2016-06-06 15:47     ` Paolo Bonzini [this message]
2016-06-08 12:16       ` Ingo Molnar
2016-06-08 12:34         ` Paolo Bonzini
2016-06-08 12:54           ` Ingo Molnar
2016-06-08 13:39             ` Paolo Bonzini
2016-06-08 13:46               ` Ingo Molnar
2016-05-30 12:30 ` [PATCH 2/2] x86/entry: Inline enter_from_user_mode Paolo Bonzini
2016-06-01 14:54   ` Rik van Riel
2016-06-04  5:08   ` Andy Lutomirski
2016-06-06 16:01     ` Paolo Bonzini
2016-06-09 17:17       ` Andy Lutomirski
2016-06-20 14:58 [PATCH v2 0/2] x86/entry: speed up context-tracking system calls by 150 clock cycles Paolo Bonzini
2016-06-20 14:58 ` [PATCH 1/2] x86/entry: Avoid interrupt flag save and restore Paolo Bonzini
2016-06-20 20:21   ` Rik van Riel
2016-06-20 20:34   ` Andy Lutomirski

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=0e02e304-a226-a35c-1109-25a35d4eae67@redhat.com \
    --to=pbonzini@redhat.com \
    --cc=hpa@zytor.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=luto@amacapital.net \
    --cc=mingo@kernel.org.com \
    --cc=peterz@infradead.org \
    --cc=riel@redhat.com \
    --cc=tglx@linutronix.de \
    --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

all inboxes | Powered by JetHome®