| Message ID | 1426716071-27570-2-git-send-email-steven@uplinklabs.net |
|---|---|
| State | Accepted |
| Headers | show |
Dear Steven Noonan, 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 ? Thanks, Thomas
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
Dear Steven Noonan, 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,) \ The last comma was unnecessary. I've removed it and committed, thanks! Thomas
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,) \ --with-pkgversion="Buildroot" \ --without-cvs \ --disable-profile \
Signed-off-by: Steven Noonan <steven@uplinklabs.net> --- package/glibc/glibc.mk | 1 + 1 file changed, 1 insertion(+)