Commit graph

3 commits

Author SHA1 Message Date
Avi Kivity
1786bf009f core: Clean up user return notifers use of per_cpu
Instead of using per_cpu(..., raw_smp_processor_id()), use
__get_cpu_var(...).

Signed-off-by: Avi Kivity <avi@redhat.com>
LKML-Reference: <1259578491-4589-1-git-send-email-avi@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-02 10:22:59 +01:00
Stephen Rothwell
3c912b6eda x86: Fix user return notifier put_cpu_var() invocation
Today's linux-next build (x86_64 allmodconfig) failed like this:

  kernel/user-return-notifier.c: In function
  'fire_user_return_notifiers': kernel/user-return-notifier.c:45:
  error: expected expression before ')' token

Introduced by commit 7c68af6e32
("core, x86: Add user return notifiers") from the tip and kvm trees
but revealed by commit e0fdb0e050eae331046385643618f12452aa7e73
("percpu: add __percpu for sparse") from the percpu tree.

Before that percpu tree commit, "put_cpu_var()" would compile
without error (even though it really needs a parameter).

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Avi Kivity <avi@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Christoph Lameter <cl@linux-foundation.org>
LKML-Reference: <20091102161722.eea4358d.sfr@canb.auug.org.au>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-02 07:58:59 +01:00
Avi Kivity
7c68af6e32 core, x86: Add user return notifiers
Add a general per-cpu notifier that is called whenever the kernel is
about to return to userspace.  The notifier uses a thread_info flag
and existing checks, so there is no impact on user return or context
switch fast paths.

This will be used initially to speed up KVM task switching by lazily
updating MSRs.

Signed-off-by: Avi Kivity <avi@redhat.com>
LKML-Reference: <1253342422-13811-1-git-send-email-avi@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-10-01 12:12:18 -07:00