public inbox for libc-stable@sourceware.org
 help / color / mirror / Atom feed
From: "H.J. Lu" <hjl.tools@gmail.com>
To: GNU C Library <libc-alpha@sourceware.org>,
	 Libc-stable Mailing List <libc-stable@sourceware.org>,
	"Carlos O'Donell" <carlos@redhat.com>,
	Florian Weimer <fweimer@redhat.com>
Subject: Re: [PATCH v2 00/10] x86-64: Avoid RTM abort inside a RTM region
Date: Mon, 29 Mar 2021 16:06:18 -0700	[thread overview]
Message-ID: <CAMe9rOpO4xShdfD=HuThk+RsyCkR+QX_uwStLwkUAusP8SMaSQ@mail.gmail.com> (raw)
In-Reply-To: <CAMe9rOoi7uK8wMo01TXKaXjJ8pF1mPchOMhop46kkb4rWeodLw@mail.gmail.com>

On Wed, Mar 24, 2021 at 11:03 AM H.J. Lu <hjl.tools@gmail.com> wrote:
>
> On Mon, Mar 15, 2021 at 7:25 AM H.J. Lu <hjl.tools@gmail.com> wrote:
> >
> > Changes in v2:
> >
> > 1. Don't use YMM2 in EVEX strcpy/strcat.
> > 2. Correct EVEX mempcpy listing.
> > 3. Use ZMM16-ZMM31 in AVX512 memmove/memset family functions.
> >
> > ---
> > Since VZEROUPPER triggers RTM abort inside a transactionally executing
> > RTM region, avoid VZEROUPPER inside a RTM region in string/memory
> > functions:
> >
> > 1. Turn on Prefer_No_VZEROUPPER for processors with RTM.
> > 2. Select functions optimized with 256-bit EVEX instructions using
> > YMM16-YMM31 registers, which don't need VZEROUPPER at function exit.
> > 3. Select AVX optimized string/memory functions with
> >
> >         xtest
> >         jz      1f
> >         vzeroall
> >         ret
> > 1:
> >         vzeroupper
> >         ret
> >
> > at function exit on processors with RTM, but without 256-bit EVEX
> > instructions.
> > 4. Since to compare 2 32-byte strings, 256-bit EVEX strcmp requires 2
> > loads, 3 VPCMPs and 2 KORDs while AVX2 strcmp requires 1 load, 2 VPCMPEQs,
> > 1 VPMINU and 1 VPMOVMSKB, AVX2 strcmp is faster than EVEX strcmp.  Add
> > Prefer_AVX2_STRCMP to prefer AVX2 strcmp family functions.
> > 5. Add tests to verify that string/memory functions won't cause RTM abort
> > in RTM region.
> > 6. Use ZMM16-ZMM31 in AVX512 memmove/memset family functions.
> >
> > H.J. Lu (10):
> >   x86: Set Prefer_No_VZEROUPPER and add Prefer_AVX2_STRCMP
> >   x86-64: Add ifunc-avx2.h functions with 256-bit EVEX
> >   x86-64: Add strcpy family functions with 256-bit EVEX
> >   x86-64: Add memmove family functions with 256-bit EVEX
> >   x86-64: Add memset family functions with 256-bit EVEX
> >   x86-64: Add memcmp family functions with 256-bit EVEX
> >   x86-64: Add AVX optimized string/memory functions for RTM
> >   x86: Add string/memory function tests in RTM region
> >   x86-64: Use ZMM16-ZMM31 in AVX512 memset family functions
> >   x86-64: Use ZMM16-ZMM31 in AVX512 memmove family functions
> >
> >  sysdeps/x86/Makefile                          |   23 +
> >  sysdeps/x86/cpu-features.c                    |   20 +-
> >  sysdeps/x86/cpu-tunables.c                    |    2 +
> >  ...cpu-features-preferred_feature_index_1.def |    1 +
> >  sysdeps/x86/tst-memchr-rtm.c                  |   54 +
> >  sysdeps/x86/tst-memcmp-rtm.c                  |   52 +
> >  sysdeps/x86/tst-memmove-rtm.c                 |   53 +
> >  sysdeps/x86/tst-memrchr-rtm.c                 |   54 +
> >  sysdeps/x86/tst-memset-rtm.c                  |   45 +
> >  sysdeps/x86/tst-strchr-rtm.c                  |   54 +
> >  sysdeps/x86/tst-strcpy-rtm.c                  |   53 +
> >  sysdeps/x86/tst-string-rtm.h                  |   72 ++
> >  sysdeps/x86/tst-strlen-rtm.c                  |   53 +
> >  sysdeps/x86/tst-strncmp-rtm.c                 |   52 +
> >  sysdeps/x86/tst-strrchr-rtm.c                 |   53 +
> >  sysdeps/x86_64/multiarch/Makefile             |   58 +-
> >  sysdeps/x86_64/multiarch/ifunc-avx2.h         |   18 +-
> >  sysdeps/x86_64/multiarch/ifunc-impl-list.c    |  381 +++++-
> >  sysdeps/x86_64/multiarch/ifunc-memcmp.h       |   17 +-
> >  sysdeps/x86_64/multiarch/ifunc-memmove.h      |   45 +-
> >  sysdeps/x86_64/multiarch/ifunc-memset.h       |   49 +-
> >  sysdeps/x86_64/multiarch/ifunc-strcpy.h       |   17 +-
> >  sysdeps/x86_64/multiarch/ifunc-wmemset.h      |   22 +-
> >  sysdeps/x86_64/multiarch/memchr-avx2-rtm.S    |   12 +
> >  sysdeps/x86_64/multiarch/memchr-avx2.S        |   45 +-
> >  sysdeps/x86_64/multiarch/memchr-evex.S        |  381 ++++++
> >  .../x86_64/multiarch/memcmp-avx2-movbe-rtm.S  |   12 +
> >  sysdeps/x86_64/multiarch/memcmp-avx2-movbe.S  |   28 +-
> >  sysdeps/x86_64/multiarch/memcmp-evex-movbe.S  |  440 +++++++
> >  .../memmove-avx-unaligned-erms-rtm.S          |   17 +
> >  .../multiarch/memmove-avx512-unaligned-erms.S |   25 +-
> >  .../multiarch/memmove-evex-unaligned-erms.S   |   33 +
> >  .../multiarch/memmove-vec-unaligned-erms.S    |   57 +-
> >  sysdeps/x86_64/multiarch/memrchr-avx2-rtm.S   |   12 +
> >  sysdeps/x86_64/multiarch/memrchr-avx2.S       |   53 +-
> >  sysdeps/x86_64/multiarch/memrchr-evex.S       |  337 ++++++
> >  .../memset-avx2-unaligned-erms-rtm.S          |   10 +
> >  .../multiarch/memset-avx2-unaligned-erms.S    |   12 +-
> >  .../multiarch/memset-avx512-unaligned-erms.S  |   16 +-
> >  .../multiarch/memset-evex-unaligned-erms.S    |   24 +
> >  .../multiarch/memset-vec-unaligned-erms.S     |   61 +-
> >  sysdeps/x86_64/multiarch/rawmemchr-avx2-rtm.S |    4 +
> >  sysdeps/x86_64/multiarch/rawmemchr-evex.S     |    4 +
> >  sysdeps/x86_64/multiarch/stpcpy-avx2-rtm.S    |    3 +
> >  sysdeps/x86_64/multiarch/stpcpy-evex.S        |    3 +
> >  sysdeps/x86_64/multiarch/stpncpy-avx2-rtm.S   |    4 +
> >  sysdeps/x86_64/multiarch/stpncpy-evex.S       |    4 +
> >  sysdeps/x86_64/multiarch/strcat-avx2-rtm.S    |   12 +
> >  sysdeps/x86_64/multiarch/strcat-avx2.S        |    6 +-
> >  sysdeps/x86_64/multiarch/strcat-evex.S        |  283 +++++
> >  sysdeps/x86_64/multiarch/strchr-avx2-rtm.S    |   12 +
> >  sysdeps/x86_64/multiarch/strchr-avx2.S        |   28 +-
> >  sysdeps/x86_64/multiarch/strchr-evex.S        |  335 ++++++
> >  sysdeps/x86_64/multiarch/strchr.c             |   17 +-
> >  sysdeps/x86_64/multiarch/strchrnul-avx2-rtm.S |    3 +
> >  sysdeps/x86_64/multiarch/strchrnul-evex.S     |    3 +
> >  sysdeps/x86_64/multiarch/strcmp-avx2-rtm.S    |   12 +
> >  sysdeps/x86_64/multiarch/strcmp-avx2.S        |   55 +-
> >  sysdeps/x86_64/multiarch/strcmp-evex.S        | 1043 +++++++++++++++++
> >  sysdeps/x86_64/multiarch/strcmp.c             |   19 +-
> >  sysdeps/x86_64/multiarch/strcpy-avx2-rtm.S    |   12 +
> >  sysdeps/x86_64/multiarch/strcpy-avx2.S        |   85 +-
> >  sysdeps/x86_64/multiarch/strcpy-evex.S        | 1003 ++++++++++++++++
> >  sysdeps/x86_64/multiarch/strlen-avx2-rtm.S    |   12 +
> >  sysdeps/x86_64/multiarch/strlen-avx2.S        |   43 +-
> >  sysdeps/x86_64/multiarch/strlen-evex.S        |  436 +++++++
> >  sysdeps/x86_64/multiarch/strncat-avx2-rtm.S   |    3 +
> >  sysdeps/x86_64/multiarch/strncat-evex.S       |    3 +
> >  sysdeps/x86_64/multiarch/strncmp-avx2-rtm.S   |    3 +
> >  sysdeps/x86_64/multiarch/strncmp-evex.S       |    3 +
> >  sysdeps/x86_64/multiarch/strncmp.c            |   19 +-
> >  sysdeps/x86_64/multiarch/strncpy-avx2-rtm.S   |    3 +
> >  sysdeps/x86_64/multiarch/strncpy-evex.S       |    3 +
> >  sysdeps/x86_64/multiarch/strnlen-avx2-rtm.S   |    4 +
> >  sysdeps/x86_64/multiarch/strnlen-evex.S       |    4 +
> >  sysdeps/x86_64/multiarch/strrchr-avx2-rtm.S   |   12 +
> >  sysdeps/x86_64/multiarch/strrchr-avx2.S       |   19 +-
> >  sysdeps/x86_64/multiarch/strrchr-evex.S       |  265 +++++
> >  sysdeps/x86_64/multiarch/wcschr-avx2-rtm.S    |    3 +
> >  sysdeps/x86_64/multiarch/wcschr-evex.S        |    3 +
> >  sysdeps/x86_64/multiarch/wcscmp-avx2-rtm.S    |    4 +
> >  sysdeps/x86_64/multiarch/wcscmp-evex.S        |    4 +
> >  sysdeps/x86_64/multiarch/wcslen-avx2-rtm.S    |    4 +
> >  sysdeps/x86_64/multiarch/wcslen-evex.S        |    4 +
> >  sysdeps/x86_64/multiarch/wcsncmp-avx2-rtm.S   |    5 +
> >  sysdeps/x86_64/multiarch/wcsncmp-evex.S       |    5 +
> >  sysdeps/x86_64/multiarch/wcsnlen-avx2-rtm.S   |    5 +
> >  sysdeps/x86_64/multiarch/wcsnlen-evex.S       |    5 +
> >  sysdeps/x86_64/multiarch/wcsnlen.c            |   18 +-
> >  sysdeps/x86_64/multiarch/wcsrchr-avx2-rtm.S   |    3 +
> >  sysdeps/x86_64/multiarch/wcsrchr-evex.S       |    3 +
> >  sysdeps/x86_64/multiarch/wmemchr-avx2-rtm.S   |    4 +
> >  sysdeps/x86_64/multiarch/wmemchr-evex.S       |    4 +
> >  .../x86_64/multiarch/wmemcmp-avx2-movbe-rtm.S |    4 +
> >  sysdeps/x86_64/multiarch/wmemcmp-evex-movbe.S |    4 +
> >  sysdeps/x86_64/sysdep.h                       |   22 +
> >  96 files changed, 6372 insertions(+), 337 deletions(-)
> >  create mode 100644 sysdeps/x86/tst-memchr-rtm.c
> >  create mode 100644 sysdeps/x86/tst-memcmp-rtm.c
> >  create mode 100644 sysdeps/x86/tst-memmove-rtm.c
> >  create mode 100644 sysdeps/x86/tst-memrchr-rtm.c
> >  create mode 100644 sysdeps/x86/tst-memset-rtm.c
> >  create mode 100644 sysdeps/x86/tst-strchr-rtm.c
> >  create mode 100644 sysdeps/x86/tst-strcpy-rtm.c
> >  create mode 100644 sysdeps/x86/tst-string-rtm.h
> >  create mode 100644 sysdeps/x86/tst-strlen-rtm.c
> >  create mode 100644 sysdeps/x86/tst-strncmp-rtm.c
> >  create mode 100644 sysdeps/x86/tst-strrchr-rtm.c
> >  create mode 100644 sysdeps/x86_64/multiarch/memchr-avx2-rtm.S
> >  create mode 100644 sysdeps/x86_64/multiarch/memchr-evex.S
> >  create mode 100644 sysdeps/x86_64/multiarch/memcmp-avx2-movbe-rtm.S
> >  create mode 100644 sysdeps/x86_64/multiarch/memcmp-evex-movbe.S
> >  create mode 100644 sysdeps/x86_64/multiarch/memmove-avx-unaligned-erms-rtm.S
> >  create mode 100644 sysdeps/x86_64/multiarch/memmove-evex-unaligned-erms.S
> >  create mode 100644 sysdeps/x86_64/multiarch/memrchr-avx2-rtm.S
> >  create mode 100644 sysdeps/x86_64/multiarch/memrchr-evex.S
> >  create mode 100644 sysdeps/x86_64/multiarch/memset-avx2-unaligned-erms-rtm.S
> >  create mode 100644 sysdeps/x86_64/multiarch/memset-evex-unaligned-erms.S
> >  create mode 100644 sysdeps/x86_64/multiarch/rawmemchr-avx2-rtm.S
> >  create mode 100644 sysdeps/x86_64/multiarch/rawmemchr-evex.S
> >  create mode 100644 sysdeps/x86_64/multiarch/stpcpy-avx2-rtm.S
> >  create mode 100644 sysdeps/x86_64/multiarch/stpcpy-evex.S
> >  create mode 100644 sysdeps/x86_64/multiarch/stpncpy-avx2-rtm.S
> >  create mode 100644 sysdeps/x86_64/multiarch/stpncpy-evex.S
> >  create mode 100644 sysdeps/x86_64/multiarch/strcat-avx2-rtm.S
> >  create mode 100644 sysdeps/x86_64/multiarch/strcat-evex.S
> >  create mode 100644 sysdeps/x86_64/multiarch/strchr-avx2-rtm.S
> >  create mode 100644 sysdeps/x86_64/multiarch/strchr-evex.S
> >  create mode 100644 sysdeps/x86_64/multiarch/strchrnul-avx2-rtm.S
> >  create mode 100644 sysdeps/x86_64/multiarch/strchrnul-evex.S
> >  create mode 100644 sysdeps/x86_64/multiarch/strcmp-avx2-rtm.S
> >  create mode 100644 sysdeps/x86_64/multiarch/strcmp-evex.S
> >  create mode 100644 sysdeps/x86_64/multiarch/strcpy-avx2-rtm.S
> >  create mode 100644 sysdeps/x86_64/multiarch/strcpy-evex.S
> >  create mode 100644 sysdeps/x86_64/multiarch/strlen-avx2-rtm.S
> >  create mode 100644 sysdeps/x86_64/multiarch/strlen-evex.S
> >  create mode 100644 sysdeps/x86_64/multiarch/strncat-avx2-rtm.S
> >  create mode 100644 sysdeps/x86_64/multiarch/strncat-evex.S
> >  create mode 100644 sysdeps/x86_64/multiarch/strncmp-avx2-rtm.S
> >  create mode 100644 sysdeps/x86_64/multiarch/strncmp-evex.S
> >  create mode 100644 sysdeps/x86_64/multiarch/strncpy-avx2-rtm.S
> >  create mode 100644 sysdeps/x86_64/multiarch/strncpy-evex.S
> >  create mode 100644 sysdeps/x86_64/multiarch/strnlen-avx2-rtm.S
> >  create mode 100644 sysdeps/x86_64/multiarch/strnlen-evex.S
> >  create mode 100644 sysdeps/x86_64/multiarch/strrchr-avx2-rtm.S
> >  create mode 100644 sysdeps/x86_64/multiarch/strrchr-evex.S
> >  create mode 100644 sysdeps/x86_64/multiarch/wcschr-avx2-rtm.S
> >  create mode 100644 sysdeps/x86_64/multiarch/wcschr-evex.S
> >  create mode 100644 sysdeps/x86_64/multiarch/wcscmp-avx2-rtm.S
> >  create mode 100644 sysdeps/x86_64/multiarch/wcscmp-evex.S
> >  create mode 100644 sysdeps/x86_64/multiarch/wcslen-avx2-rtm.S
> >  create mode 100644 sysdeps/x86_64/multiarch/wcslen-evex.S
> >  create mode 100644 sysdeps/x86_64/multiarch/wcsncmp-avx2-rtm.S
> >  create mode 100644 sysdeps/x86_64/multiarch/wcsncmp-evex.S
> >  create mode 100644 sysdeps/x86_64/multiarch/wcsnlen-avx2-rtm.S
> >  create mode 100644 sysdeps/x86_64/multiarch/wcsnlen-evex.S
> >  create mode 100644 sysdeps/x86_64/multiarch/wcsrchr-avx2-rtm.S
> >  create mode 100644 sysdeps/x86_64/multiarch/wcsrchr-evex.S
> >  create mode 100644 sysdeps/x86_64/multiarch/wmemchr-avx2-rtm.S
> >  create mode 100644 sysdeps/x86_64/multiarch/wmemchr-evex.S
> >  create mode 100644 sysdeps/x86_64/multiarch/wmemcmp-avx2-movbe-rtm.S
> >  create mode 100644 sysdeps/x86_64/multiarch/wmemcmp-evex-movbe.S
> >
> > --
> > 2.30.2
> >
>
> These patches have been tested internally and externally for more than 2
> weeks.  I have been running the patched system glibc on AVX and AVX512
> machines.   If there are no objections nor comments, I will check them in
> next Tuesday.
>

I checked all 10 patches into master branch.  Here are backports for
2.33 to 2.28 branches:

https://gitlab.com/x86-glibc/glibc/-/commits/users/hjl/pr27457/2.33
https://gitlab.com/x86-glibc/glibc/-/commits/users/hjl/pr27457/2.32
https://gitlab.com/x86-glibc/glibc/-/commits/users/hjl/pr27457/2.31
https://gitlab.com/x86-glibc/glibc/-/commits/users/hjl/pr27457/2.30
https://gitlab.com/x86-glibc/glibc/-/commits/users/hjl/pr27457/2.29
https://gitlab.com/x86-glibc/glibc/-/commits/users/hjl/pr27457/2.28

-- 
H.J.

       reply	other threads:[~2021-03-29 23:06 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <20210315142520.1661407-1-hjl.tools@gmail.com>
     [not found] ` <CAMe9rOoi7uK8wMo01TXKaXjJ8pF1mPchOMhop46kkb4rWeodLw@mail.gmail.com>
2021-03-29 23:06   ` H.J. Lu [this message]
2022-01-27 17:13     ` H.J. Lu

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='CAMe9rOpO4xShdfD=HuThk+RsyCkR+QX_uwStLwkUAusP8SMaSQ@mail.gmail.com' \
    --to=hjl.tools@gmail.com \
    --cc=carlos@redhat.com \
    --cc=fweimer@redhat.com \
    --cc=libc-alpha@sourceware.org \
    --cc=libc-stable@sourceware.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 read-only IMAP folder(s) and NNTP newsgroup(s).