By writing directly, a memory access violation can occur whilst
hotplugging a CPU if the entry was previously marked read-only.
Signed-off-by: NAlex Nixon <alex.nixon@citrix.com>
Cc: Jeremy Fitzhardinge <Jeremy.Fitzhardinge@citrix.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This converts x86, x86-64, and xen to use the new helpers for
smp_call_function() and friends, and adds support for
smp_call_function_single().
Acked-by: NIngo Molnar <mingo@elte.hu>
Acked-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

This patch creates smpcommon.c with functions that are
equal between architectures. The i386-only init_gdt
is ifdef'd.

Note that smpcommon.o figures twice in the Makefile:
this is because sub-architectures like voyager that does
not use the normal smp_$(BITS) files also have to access them
Signed-off-by: NGlauber Costa <gcosta@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This patch changes the write_gdt_entry function signature.
Instead of the old "a" and "b" parameters, it now receives
a pointer to a desc_struct, and the size of the entry being
handled. This is because x86_64 can have some 16-byte entries
as well as 8-byte ones.
Signed-off-by: NGlauber de Oliveira Costa <gcosta@redhat.com>
CC: Zachary Amsden <zach@vmware.com>
CC: Jeremy Fitzhardinge <Jeremy.Fitzhardinge.citrix.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This removes the requirement for callers to get_cpu() to check in simple
cases.

Cc: Andi Kleen <ak@suse.de>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

Several parts of kernel/smp.c and smpboot.c are generally useful for other
subarchitectures and paravirt_ops implementations, so make them available for
reuse.
Signed-off-by: NJeremy Fitzhardinge <jeremy@xensource.com>
Acked-by: NChris Wright <chrisw@sous-sol.org>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>