linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Andy Lutomirski <luto@kernel.org>
To: x86@kernel.org, linux-kernel@vger.kernel.org
Cc: "Brian Gerst" <brgerst@gmail.com>,
	"Linus Torvalds" <torvalds@linux-foundation.org>,
	"Borislav Petkov" <bp@alien8.de>,
	"Frédéric Weisbecker" <fweisbec@gmail.com>,
	"Peter Zijlstra" <peterz@infradead.org>,
	"Andy Lutomirski" <luto@kernel.org>
Subject: [PATCH v3 0/5] x86 entry stuff, maybe for 4.4
Date: Thu, 12 Nov 2015 12:58:59 -0800	[thread overview]
Message-ID: <cover.1447361906.git.luto@kernel.org> (raw)

The first patch is a bit ugly, but it fixes a bug that could affect
lockdep.  That bug is very minor and may not be observable at all,
but I don't really want to bet on it.

The other three are intended to fix a performance regression in the
entry rework that Frédéric objected to.  They're much later than I'd
like to have sent them for 4.4, but they're kind-of sort-of
regression fixes, so maybe they're still okay.  They would certainly
need careful review, though.

I don't have a great benchmark for them.  The biggest impact is
likely to be to user page fault latency on CONFIG_CONTEXT_TRACKING=y
kernels (i.e. distro kernels) that don't use context tracking
(i.e. most users).

Changes from v3: Actually send entire series (patch 1 was missing)

Changes from v1:
 - CALL_ENTER_FROM_USER_MODE is now CALL_enter_from_user_mode (Ingo)
 - STATIC_JUMP_IF_{TRUE,FALSE} now cannot be (mis-)used on non-jump-label
   kernels (Thomas)
 - Comments are better (Borislav)

This doesn't really address Thomas' objections to the HAVE_JUMP_LABEL stuff,
but it's more robust now, and maybe that's good enough.

Andy Lutomirski (5):
  x86/entry/64: Fix irqflag tracing wrt context tracking
  context_tracking: Switch to new static_branch API
  x86/asm: Error out if asm/jump_label.h is included inappropriately
  x86/asm: Add asm macros for static keys/jump labels
  x86/entry/64: Bypass enter_from_user_mode on non-context-tracking
    boots

 arch/x86/entry/calling.h               | 15 ++++++++
 arch/x86/entry/entry_64.S              | 27 +++++++++++----
 arch/x86/include/asm/jump_label.h      | 63 ++++++++++++++++++++++++++++++----
 include/linux/context_tracking_state.h |  4 +--
 kernel/context_tracking.c              |  4 +--
 5 files changed, 95 insertions(+), 18 deletions(-)

-- 
2.5.0


             reply	other threads:[~2015-11-12 20:59 UTC|newest]

Thread overview: 19+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-11-12 20:58 Andy Lutomirski [this message]
2015-11-12 20:59 ` [PATCH v3 1/5] x86/entry/64: Fix irqflag tracing wrt context tracking Andy Lutomirski
2015-11-24  9:35   ` [tip:x86/asm] " tip-bot for Andy Lutomirski
2015-11-12 20:59 ` [PATCH v3 2/5] context_tracking: Switch to new static_branch API Andy Lutomirski
2015-11-24  9:35   ` [tip:x86/asm] " tip-bot for Andy Lutomirski
2015-11-12 20:59 ` [PATCH v3 3/5] x86/asm: Error out if asm/jump_label.h is included inappropriately Andy Lutomirski
2015-11-13 14:13   ` Thomas Gleixner
2015-11-24  9:35   ` [tip:x86/asm] x86/asm: Error out if asm/ jump_label.h " tip-bot for Andy Lutomirski
2015-11-12 20:59 ` [PATCH v3 4/5] x86/asm: Add asm macros for static keys/jump labels Andy Lutomirski
2015-11-13 14:22   ` Thomas Gleixner
2015-11-24  9:36   ` [tip:x86/asm] " tip-bot for Andy Lutomirski
2015-11-12 20:59 ` [PATCH v3 5/5] x86/entry/64: Bypass enter_from_user_mode on non-context-tracking boots Andy Lutomirski
2015-11-13 14:23   ` Thomas Gleixner
2015-11-13 15:26   ` Frederic Weisbecker
2015-11-16 19:10     ` Andy Lutomirski
2015-11-16 22:50       ` Frederic Weisbecker
2015-11-16 23:57         ` Andy Lutomirski
2015-11-19  0:57           ` Frederic Weisbecker
2015-11-24  9:36   ` [tip:x86/asm] " tip-bot for 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=cover.1447361906.git.luto@kernel.org \
    --to=luto@kernel.org \
    --cc=bp@alien8.de \
    --cc=brgerst@gmail.com \
    --cc=fweisbec@gmail.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=peterz@infradead.org \
    --cc=torvalds@linux-foundation.org \
    --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).