Linux SNPS ARC Archive on lore.kernel.org
 help / color / Atom feed
From: lsorense@csclub.uwaterloo.ca (Lennart Sorensen)
To: Helmut Grohne <helmut@subdivi.de>,
	Alexey Brodkin <Alexey.Brodkin@synopsys.com>,
	"debian-arm@lists.debian.org" <debian-arm@lists.debian.org>,
	arcml <linux-snps-arc@lists.infradead.org>,
	GNU C Library <libc-alpha@sourceware.org>,
	Vineet Gupta <vineetg76@gmail.com>,
	Claudiu Zissulescu <Claudiu.Zissulescu@synopsys.com>,
	Vineet Gupta <Vineet.Gupta1@synopsys.com>
Subject: Re: ARC rebootstrap prereq (was Re: switching ARC to 64-bit time_t )
Date: Thu, 26 Mar 2020 15:04:28 -0400
Message-ID: <20200326190428.dxgq6vetirgq5ixy@csclub.uwaterloo.ca> (raw)
In-Reply-To: <20200326142836.GA24503@alf.mars>

On Thu, Mar 26, 2020 at 03:28:36PM +0100, Helmut Grohne wrote:
> One part of the question here is "why do we need libatomic-ops?". The
> answer to that is, because libgc uses it and libgc is used by e.g.  gcc,
> gnutls, guile, and make. Possibly, some of these could be built without
> libgc, but this is how they are packaged for Debian at present.  Package
> dependencies currently say that we need libatomic-ops.
> 
> The other part is "what is missing in libatomic-ops"? If you look at a
> more recent implementation, such as riscv, you see that it basically
> says "trust gcc". So I guess all you need here is an arc-specific
> implementation that says "gcc knows what it is doing, use its
> primitives".
> 
> Given sufficient work, I guess libatomic-ops could be removed in favour
> of using the gcc built-ins directly. Not sure whether that'd fly with
> libgc upstream though.
> 
> So no, this is not a stupid question. Thank you for asking.

The way I read the details on libatomic is that it provides functions
to implement the things a given architecture can't do with intrinsics
in gcc directly.  So on some architectures it does nothing and on others
it implements missing bits for atomic operations.

-- 
Len Sorensen

_______________________________________________
linux-snps-arc mailing list
linux-snps-arc@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-snps-arc

  reply index

Thread overview: 58+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <cover.1578824547.git.alistair.francis@wdc.com>
     [not found] ` <4e95f95966d8d7c6a8339160dc62d81c1f6a1bfb.1578824547.git.alistair.francis@wdc.com>
2020-02-12  0:14   ` [RFC v6 07/23] RISC-V: Use 64-bit time_t and off_t for RV32 and RV64 Vineet Gupta
2020-02-12  0:14     ` Alistair Francis
2020-02-12  1:30       ` Joseph Myers
2020-02-14 22:39         ` Alistair Francis
2020-02-18 23:05           ` switching ARC to 64-bit time_t (Re: [RFC v6 07/23] RISC-V: Use 64-bit time_t and off_t for RV32 and RV64) Vineet Gupta
2020-02-18 23:13             ` Joseph Myers
2020-02-19 23:09               ` Lukasz Majewski
2020-02-19 23:11             ` Lukasz Majewski
2020-02-20  8:31               ` Arnd Bergmann
2020-02-20  9:37                 ` Lukasz Majewski
2020-02-20 12:37                   ` Arnd Bergmann
2020-02-20 13:14                     ` Lukasz Majewski
2020-02-20 14:44                       ` Arnd Bergmann
2020-02-20 15:42                         ` Lukasz Majewski
2020-02-20 16:08                           ` Arnd Bergmann
2020-02-20 16:31                             ` Lukasz Majewski
2020-02-24  2:48                         ` Viresh Kumar
2020-02-21 19:56                     ` Alistair Francis
2020-02-22  8:42                   ` Arnd Bergmann
2020-02-24  9:00                     ` Lukasz Majewski
2020-02-24  9:46                       ` Andreas Schwab
2020-02-24 10:14                         ` Lukasz Majewski
2020-02-24 10:23                           ` Andreas Schwab
2020-02-24 10:36                             ` Lukasz Majewski
2020-02-24 10:42                               ` Andreas Schwab
2020-02-24 11:13                                 ` Lukasz Majewski
2020-02-24 12:41                                   ` Lukasz Majewski
2020-02-25  0:03                               ` Joseph Myers
2020-02-25 11:39                                 ` Lukasz Majewski
2020-02-25 14:36                                   ` Joseph Myers
2020-02-26 13:18                                     ` Lukasz Majewski
2020-02-26 14:48                                       ` Joseph Myers
2020-02-26 16:28                                         ` Lukasz Majewski
2020-02-25  9:03                       ` Arnd Bergmann
2020-02-20 16:27                 ` Helmut Grohne
2020-03-26  0:25                   ` ARC rebootstrap prereq (was Re: switching ARC to 64-bit time_t ) Vineet Gupta
2020-03-26  5:54                     ` Helmut Grohne
2020-03-26 11:51                       ` Alexey Brodkin
2020-03-26 12:24                         ` Helmut Grohne
2020-03-26 12:53                           ` Alexey Brodkin
2020-03-26 14:28                             ` Helmut Grohne
2020-03-26 19:04                               ` Lennart Sorensen [this message]
2020-08-26 14:39                       ` Vineet Gupta
2020-08-26 15:43                         ` Helmut Grohne
2020-08-26 21:16                           ` Aurelien Jarno
2020-02-12  1:42       ` [RFC v6 07/23] RISC-V: Use 64-bit time_t and off_t for RV32 and RV64 Vineet Gupta
2020-02-12 12:58         ` Arnd Bergmann
2020-02-19  0:56   ` Vineet Gupta
2020-02-19  1:03     ` Alistair Francis
2020-02-19  1:31       ` Vineet Gupta
2020-02-19  8:30         ` Andreas Schwab
2020-02-19 18:42           ` Vineet Gupta
2020-02-19 23:18             ` Lukasz Majewski
2020-02-20  0:26               ` Vineet Gupta
2020-02-20  0:46                 ` Joseph Myers
2020-02-20  8:24                   ` Arnd Bergmann
2020-02-20 10:28                     ` Lukasz Majewski
2020-02-20 14:14                     ` Joseph 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=20200326190428.dxgq6vetirgq5ixy@csclub.uwaterloo.ca \
    --to=lsorense@csclub.uwaterloo.ca \
    --cc=Alexey.Brodkin@synopsys.com \
    --cc=Claudiu.Zissulescu@synopsys.com \
    --cc=Vineet.Gupta1@synopsys.com \
    --cc=debian-arm@lists.debian.org \
    --cc=helmut@subdivi.de \
    --cc=libc-alpha@sourceware.org \
    --cc=linux-snps-arc@lists.infradead.org \
    --cc=vineetg76@gmail.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

Linux SNPS ARC Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-snps-arc/0 linux-snps-arc/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-snps-arc linux-snps-arc/ https://lore.kernel.org/linux-snps-arc \
		linux-snps-arc@lists.infradead.org
	public-inbox-index linux-snps-arc

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.infradead.lists.linux-snps-arc


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git