Memory Barriers for (Ubuntu) Linux (i686) Post: 302430086

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Special Forums UNIX and Linux Applications High Performance Computing Memory Barriers for (Ubuntu) Linux (i686) Post 302430086 by Corona688 on Wednesday 16th of June 2010 02:00:46 PM

06-16-2010

Registered User

I know you want to avoid mutexes, but this is really what they're for. You could try using Linux futexes, which handle the nonblocking case completely in userspace, but I'm not sure what that'd do for memory barriers(this MAY have something to do with a special mmap flag to create the futex pages, though I think futexes have changed several times since I began fiddling with them) -- and modern Linux NPTL pthreads is based on futexes anyway, so you'd just be reinventing pthreads.

Besides, what if you need to move it to MIPS or something?

[edit] One thought does occur to me. How large are these structures? Could you perhaps reorder it to put prefix, instance, and state in order in memory? You could assemble the data in an MMX or SSE register, then overwrite several structure members in one assembly op.

Last edited by Corona688; 06-16-2010 at 03:15 PM..

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LEARN ABOUT DEBIAN

import-bug-from-debian

import-bug-from-debian(1)				      General Commands Manual					 import-bug-from-debian(1)

NAME

       import-bug-from-debian - Import bugs from Debian's BTS, and file them against Ubuntu in LP.

SYNOPSIS

       import-bug-from-debian [options] bug...
       import-bug-from-debian -h

DESCRIPTION

       import-bug-from-debian  clones  bugs  from Debian's BTS into Launchpad. Each bug listed on the command line has its initial report re-filed
       against the same source package in Ubuntu.  The Ubuntu bug is linked back to its Debian counterpart.

       Each bug may be provided either as a bug number or URL.

OPTIONS

       -b, --browserless
	      Don't open the bug in a browser at the end.

       -h, --help
	      Display a help message and exit.

       -l INSTANCE, --lpinstance=INSTANCE
	      Use the specified instance of Launchpad (e.g. "staging"), instead of the default of "production".

       -p PACKAGE, --package=PACKAGE
	      Launchpad package to file bug against, if not the same source package name as Debian.   Useful  for  importing  removal  bugs  filed
	      against ftp.debian.org.

       --no-conf
	      Do not read any configuration files, or configuration from environment variables.

ENVIRONMENT

       All  of	the  CONFIGURATION  VARIABLES  below are also supported as environment variables.  Variables in the environment take precedence to
       those in configuration files.

CONFIGURATION VARIABLES

       The following variables can be set in the environment or in ubuntu-dev-tools(5) configuration files.  In  each  case,  the  script-specific
       variable takes precedence over the package-wide variable.

       IMPORT_BUG_FROM_DEBIAN_LPINSTANCE, UBUNTUTOOLS_LPINSTANCE
	      The default value for --lpinstance.

SEE ALSO

       ubuntu-dev-tools(5)

AUTHORS

       import-bug-from-debian  was  written  by  James	Westby <james.westby@ubuntu.com>, and this manual page was written by Stefano Rivera <ste-
       fanor@ubuntu.com>.

       Both are released under the terms of the GNU General Public License, version 2.

ubuntu-dev-tools						 September 21 2010					 import-bug-from-debian(1)