]> git.openfabrics.org - ~shefty/rdma-dev.git/commit
x86: "nosmp" command line option should force the system into UP mode
authorJan Beulich <JBeulich@novell.com>
Mon, 24 May 2010 19:13:17 +0000 (12:13 -0700)
committerH. Peter Anvin <hpa@linux.intel.com>
Mon, 24 May 2010 20:31:52 +0000 (13:31 -0700)
commit5f2eb55026c91f8400ab4469aff88b2e201b5616
tree1cef5c2d26e0b38f3f9f61f103d6de840f7f2061
parentb46fc5f235be04a7f77fb2af1d8cb809889c25c1
x86: "nosmp" command line option should force the system into UP mode

Bits set in cpu_possible_mask prior to the execution of
prefill_possible_map() (i.e.  when parsing ACPI or MPS tables) would
prevent the SMP alternatives logic from switching to UP mode, plus
unnecessary setup of per-CPU data for CPUs that can never come online.

Additionally, without CONFIG_HOTPLUG_CPU disabled CPUs can never come
online, and hence setting cpu_possible_mask bits for them is again a
simple waste of resources.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
LKML-Reference: <201005241913.o4OJDH3Z010874@imap1.linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
arch/x86/kernel/smpboot.c