kern/145385: [cpu] Logical processor cannot be disabled for some SMT-enabled Intel procs

[Andriy Gapon]

The following reply was made to PR kern/145385; it has been noted by GNATS.

From: Andriy Gapon <avg at freebsd.org>
To: bug-followup at freebsd.org, gcooper at freebsd.org
Cc:  
Subject: Re: kern/145385: [cpu] Logical processor cannot be disabled for some
 SMT-enabled Intel procs
Date: Thu, 07 Oct 2010 20:03:14 +0300

 Here's a patch to remove halted logical processors from root cpu set (cpuset
 number zero) and consequently all child sets:
 http://people.freebsd.org/~avg/cpu-halt.diff
 
 Please note that unhalting CPUs will add them to cpuset zero, but will not
 (re-)add them cpusets of the running processes.  So additional action will be
 required from system administrator if e would like existing processes to make use
 of unhalted CPUs.
 
 Also, interrupts that are bound to halted CPUs are not rebound on halt, and so
 will be delivered to halted CPUs.  This should not be a problem for typical
 environments, but would be nice to fix anyway.
 
 -- 
 Andriy Gapon