From: "Joseph S. Myers" <joseph@codesourcery.com>
To: Dinar Temirbulatov <dinar@kugelworks.com>
Cc: <libc-ports@sourceware.org>, <adeb@nvidia.com>
Subject: Re: [Patch] ARM define atomic_exchange_acq/atomic_exchange_rel to __atomic_exchange_n
Date: Sun, 18 Aug 2013 20:29:00 -0000 [thread overview]
Message-ID: <Pine.LNX.4.64.1308182022000.10353@digraph.polyomino.org.uk> (raw)
In-Reply-To: <CANoaTN2hKTZ7GZCMsYqai25PHO7GLb56huLosR7+dgjAEK2FGQ@mail.gmail.com>
On Tue, 13 Aug 2013, Dinar Temirbulatov wrote:
> Hello,
> Following patch redefines atomic_exchange_acq/atomic_exchange_rel to
> __atomic_exchange_n for ARM, that allows for example to reduce number
> of instruction sequence for lll_unlock
> from:
> ldex, cmp, bne, stex, cmp, bne
> to
> ldex, stex, cmp, bne
> , more on the issue here:
> http://sourceware.org/bugzilla/show_bug.cgi?id=15640
>
> This patch was tested on ARM a9 with glibc testsuite with no new
> regressions. OK to commit?
What does this do when building for an ARM architecture version where the
kernel helpers need to be used for atomicity?
I think what's desired in such a case is for the operations to continue to
be expanded with inline calls to the kernel helpers. Generating
out-of-line calls to libgcc helpers would be less desirable (and
out-of-line calls to anything not in libgcc.a would break the build).
--
Joseph S. Myers
joseph@codesourcery.com
next prev parent reply other threads:[~2013-08-18 20:29 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-08-13 17:11 Dinar Temirbulatov
2013-08-15 21:46 ` Abhishek Deb
2013-08-16 22:57 ` Dinar Temirbulatov
2013-08-17 2:42 ` Abhishek Deb
2013-08-19 19:21 ` Dinar Temirbulatov
2013-08-18 20:29 ` Joseph S. Myers [this message]
2013-09-01 20:42 Dinar Temirbulatov
2013-09-01 20:43 Dinar Temirbulatov
2013-09-02 15:08 ` Joseph S. Myers
2013-09-03 17:31 ` Abhishek Deb
2013-09-05 12:56 ` Dinar Temirbulatov
2013-09-05 15:48 ` Joseph S. Myers
2013-09-05 17:09 ` Abhishek Deb
2013-09-11 19:25 ` Dinar Temirbulatov
2013-09-11 19:27 ` Dinar Temirbulatov
2013-09-11 20:40 ` Abhishek Deb
2013-09-13 17:14 ` Joseph S. Myers
2013-09-14 3:29 ` Dinar Temirbulatov
2013-09-18 17:16 ` Joseph S. Myers
2013-09-19 6:53 ` Maxim Kuvyrkov
2013-09-19 16:29 ` Joseph S. Myers
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=Pine.LNX.4.64.1308182022000.10353@digraph.polyomino.org.uk \
--to=joseph@codesourcery.com \
--cc=adeb@nvidia.com \
--cc=dinar@kugelworks.com \
--cc=libc-ports@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).