From: Baruch Siach <baruch@tkos.co.il>
To: buildroot@busybox.net
Subject: [Buildroot] [PATCH] package/glibc: enable lock elision on x86_64 hosts
Date: Sun, 19 Jul 2015 12:33:00 +0300 [thread overview]
Message-ID: <20150719093300.GG13027@tarshish> (raw)
In-Reply-To: <20150719112314.2d733eaf@free-electrons.com>
Hi Thomas,
On Sun, Jul 19, 2015 at 11:23:14AM +0200, Thomas Petazzoni wrote:
> On Wed, 18 Mar 2015 15:01:09 -0700, Steven Noonan wrote:
> > Signed-off-by: Steven Noonan <steven@uplinklabs.net>
> > ---
> > package/glibc/glibc.mk | 1 +
> > 1 file changed, 1 insertion(+)
> >
> > diff --git a/package/glibc/glibc.mk b/package/glibc/glibc.mk
> > index 0a37bb3..651711a 100644
> > --- a/package/glibc/glibc.mk
> > +++ b/package/glibc/glibc.mk
> > @@ -90,6 +90,7 @@ define GLIBC_CONFIGURE_CMDS
> > --prefix=/usr \
> > --enable-shared \
> > $(if $(BR2_SOFT_FLOAT),--without-fp,--with-fp) \
> > + $(if $(BR2_x86_64),--enable-lock-elision,) \
>
> What happens on x86-64 processors that don't have the HW support needed
> for lock elision ? Does glibc gracefully falls back at runtime to
> "normal" locks ?
According to the code at sysdeps/unix/sysv/linux/x86/elision-conf.c,
__elision_available is initialized from HAS_RTM which is evaluated at run-time
(sysdeps/x86_64/multiarch/init-arch.h).
baruch
--
http://baruch.siach.name/blog/ ~. .~ Tk Open Systems
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next prev parent reply other threads:[~2015-07-19 9:33 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-03-18 22:01 [Buildroot] [PATCH 1/3] arch: add corei7-avx Steven Noonan
2015-03-18 22:01 ` [Buildroot] [PATCH] package/glibc: enable lock elision on x86_64 hosts Steven Noonan
2015-07-19 9:23 ` Thomas Petazzoni
2015-07-19 9:33 ` Baruch Siach [this message]
2015-07-20 20:57 ` Thomas Petazzoni
2015-03-18 22:01 ` [Buildroot] [PATCH 2/3] arch: add core-avx2 Steven Noonan
2015-04-09 20:19 ` Gustavo Zacarias
2015-03-18 22:01 ` [Buildroot] [PATCH 3/3] packages: add AVX/AVX2 support to ffmpeg/opencv Steven Noonan
2015-04-09 20:16 ` [Buildroot] [PATCH 1/3] arch: add corei7-avx Gustavo Zacarias
2015-04-09 21:35 ` Thomas Petazzoni
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